Usmle step 1 Sample Test Questions
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- Bu səhifədəki naviqasiya:
- HDL-cholesterol Triglycerides
- Fatal MI
- Calcium Inorganic Phosphorus 1,25-Dihydroxycholecalciferol Erythropoietin
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Serum Arterial Blood
3 −
P CO 2
(A) ↑ ↓ ↑ (B) ↓ ↓ ↓ (C)
↑ ↑ ↓ (D) ↓ ↓ ↑ (E)
↑ ↑ ↑
39. A 32-year-old woman with rheumatoid arthritis comes to the physician for a follow-up examination. Six months ago, she began treatment with a drug that blocks tumor necrosis factor. She says that initially her symptoms improved, but her joint pain has increased during the past 3 weeks. Physical examination shows swollen, tender, stiff joints in the hands and knees. Which of the following is the most likely cause of the loss of drug efficacy in this patient?
(A) Decreased B-lymphocyte sensitivity to the drug (B) Decreased T-lymphocyte sensitivity to the drug (C) Development of antibodies to the drug (D) Impaired absorption of the drug from the gastrointestinal tract (E) Increased elimination of the drug from the body
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40. An otherwise healthy 45-year-old man comes to the physician because of a 3-week history of progressive epigastric heartburn and a 4.5-kg (10-lb) weight loss. The pain tends to be more severe at night and occurs 1 to 3 hours after meals during the day. He has had similar episodes with lesser intensity during the past year. Abdominal examination shows tenderness to deep palpation. Test of the stool for occult blood is positive. Endoscopy shows a bleeding 3-cm ulcer in the antrum of the stomach. A photomicrograph of Steiner silver-stained tissue (400x) from a biopsy of the gastric mucosa adjacent to the ulcer is shown. Which of the following processes is most likely to be involved?
(A) Elaboration of proteases and urease with local tissue destruction (B) Hyperacidity and gastric ulcer development (C) Ingestion of preformed toxins in contaminated well water (D) Spirochete invasion of gastric cells
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USMLE STEP 1 SAMPLE TEST QUESTIONS
41.
A new blood test to detect prostate cancer is evaluated in 300 male volunteers. A needle biopsy of the prostate gland is done on all men with serum prostate-specific antigen concentrations greater than 5 ng/mL (N<4). One hundred men undergo biopsy procedures; 90 are found to have prostate cancer, and five are found to have chronic prostatitis. Which of the following is necessary to calculate the sensitivity of this test?
(A) Incidence of chronic prostatitis in the general population (B) Number of men with test results greater than 5 ng/mL and a normal biopsy specimen (C) Prevalence of chronic prostatitis in the general population (D) Prostate biopsies of men with test results equal to or below 5 ng/mL
42. A 64-year-old man comes to the physician because of swelling in his feet for the past 2 years. He says that his skin is dry and itchy and his feet "feel heavy." One of his legs is shown. Which of the following is the most likely cause of his condition?
(A) Arteriolar constriction and arteriolar hypertension (B) Arteriolar dilation and venous hypertension (C) Venous constriction and arteriolar constriction (D) Venous hypertension and incompetent valves (E) Venous hypertension and venous constriction
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43.
A 32-year-old woman with HIV infection is brought to the emergency department 15 minutes after she had a generalized tonic-clonic seizure. She has a 1-day history of right-sided weakness. Her temperature is 38.5°C (101.3°F). Muscle strength is 4/5 in the right upper extremities and 4/5 in the right lower extremity. Laboratory studies show a positive anti-Toxoplasma IgG and positive anti-cytomegalovirus IgG. Her CD4+ T-lymphocyte count is 32/mm 3 (N≥500), and plasma HIV viral load is 84,000 copies/mL. A gadolinium-enhanced MRI of the brain shows multiple ring-enhancing lesions. Infection with which of the following agents is the most likely cause of the findings in this patient?
(A) Cryptococcus neoformans (B) Cytomegalovirus (C) Epstein-Barr virus (D) Neisseria meningitidis (E) Streptococcus pneumoniae (F) Toxoplasma gondii
44.
A previously healthy 27-year-old man is brought to the emergency department 30 minutes after sustaining stab wounds to the right side of his neck and arm. He has lost approximately 1000 mL of blood. His pulse is 110/min, respirations are 22/min, and blood pressure is 95/65 mm Hg. Physical examination shows lacerations of the right side of the neck and right upper extremity. Which of the following responses by the kidneys is most likely?
(A) Acute tubular necrosis (B) Osmotic diuresis (C) Sodium wasting (D) Vasoconstriction (E) Water conservation
A 57-year-old man receives radiation therapy for a squamous cell carcinoma of the lung. Despite therapy, the tumor progressively increases in size, and he dies 6 months later. His tumor cells contain a point mutation in the p53 gene (TP53), leading to an inactive gene product. Based on this finding, the progressive tumor growth despite irradiation therapy is most likely to be related to a defect in cell cycle arrest in which of the following phases of the cell cycle?
(A) G 0 (B) G
1 (C) G
2 (D) M
(E) S
46.
A male stillborn is delivered at 32 weeks' gestation to a 30-year-old woman. The pregnancy was complicated by oligohydramnios. Examination of the stillborn shows the absence of a urethral opening. Which of the following additional findings is most likely in this stillborn?
(A) Congenital diaphragmatic hernia (B) Intralobar sequestration (C) Pulmonary hypoplasia (D) Situs inversus (E) Tracheoesophageal fistula
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47.
A 36-year-old man with profound intellectual disability is brought to the physician by staff at his facility because of increasing abdominal girth during the past 2 weeks. He is unable to speak, and no medical history is currently available. Physical examination shows a protuberant abdomen with a fluid wave and shifting dullness. There are no signs of trauma to the area. Laboratory studies show no abnormalities. A CT scan of the abdomen is shown. Fluid is present in which of the following areas as indicated by the arrow?
(A) Epiploic foramen (B) Gastrosplenic ligament (C) Hepatorenal pouch (of Morison) (D) Omental bursa (lesser sac) (E) Sulcus pericolicus
A 59-year-old woman comes to the physician because of yellow skin for 5 days. Physical examination shows jaundice. There is mild epigastric tenderness on deep palpation. Serum studies show:
Bilirubin, total 9.6 mg/dL Direct 8.9 mg/dL Alkaline phosphatase 310 U/L AST
29 U/L ALT
31 U/L
A CT scan of the abdomen shows a 3-cm mass at the head of the pancreas. Examination of material from the mass obtained by fine-needle aspiration shows numerous anaplastic cells. These cells most likely originated from which of the following components of the pancreas?
(A) Acinar epithelium (B) Duct epithelium (C) Interstitial adipose tissue (D) Interstitial fibrous tissue (E) Islet of Langerhans (F) Vascular endothelium
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49.
A full-term female newborn is examined shortly after birth. She appears to be small for gestational age, and she has excess skin on the nape of the neck and lymphedema of the hands and feet. Chromosomal analysis shows some cells with a normal 46,XY karyotype and some cells with a 45,X karyotype. Which of the following mechanisms best explains this cytogenetic abnormality?
(A) Nondisjunction in mitosis (B) Reciprocal translocation (C) Robertsonian translocation (D) Skewed X-inactivation (E) Uniparental disomy
A 49-year-old woman comes to the physician for a follow-up examination. She has a strong family history of coronary artery disease. Her blood pressure has ranged from 150/95 mm Hg to 130/85 mm Hg during the previous three visits within the past 2 months. Her blood pressure today is 140/90 mm Hg. Physical examination shows no other abnormalities. Laboratory studies show:
Cholesterol, total 290 mg/dL HDL-cholesterol 40 mg/dL LDL-cholesterol 190 mg/dL Triglycerides 350 mg/dL
Treatment with atorvastatin and losartan is initiated. Which of the following serum findings is most likely to occur in this patient?
HDL-cholesterol Triglycerides (A)
Decreased decreased (B) Decreased increased (C)
Increased decreased (D) Increased increased (E)
No change no change
A 12-year-old boy is brought to the physician by his father because of redness and swelling of his left foot for 24 hours. Three days ago, the boy scraped his foot while wading in a drainage ditch. Examination of the left foot shows a purulent abrasion with edema, erythema, and tenderness on the lateral side. Infection is most likely to next spread from the lateral side of the foot to the regional lymph nodes in which of the following areas?
(A) Lateral surface of the thigh (B) Medial malleolus, posteriorly (C) Popliteal fossa (D) Sole of the foot (E) Superficial inguinal area
A 6-day-old breast-fed boy is brought to the emergency department by his mother because of poor weight gain and irritability since delivery, and a 2-hour history of vomiting. Physical examination shows jaundice and hepatomegaly. A reducing substance test result of the urine is positive, and a glucose oxidase test result is negative. The concentration of which of the following metabolites in liver is most likely increased in this patient?
(A) Fructose 1,6-bisphosphate (B) Galactose 1-phosphate (C) Glucose 1-phosphate (D) Glucose 6-phosphate
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53.
A randomized clinical trial is conducted to assess whether statin use decreases mortality due to myocardial infarction (MI). A total of 2000 participants are enrolled: 1000 participants receive treatment with statins, and 1000 participants receive placebo. Participants are followed for an average of 5 years. Results are shown:
Fatal MI
Yes No Total Treatment Statins 15
985 1000
Placebo 25
975 1000
Total 40
1960 2000
The investigators calculate that the cost of the drug is $1000 per patient per year. Based on these data, which of the following best represents the cost of the drug to prevent one death due to MI over the 5-year period?
(A) $1500 (B) $5000 (C) $15,000 (D) $50,000 (E) $150,000 (F) $500,000
54.
A 68-year-old woman has the sudden onset of weakness in her right arm and leg. She can speak, but her words are not enunciated clearly. Neurologic examination 6 weeks later shows an extensor plantar reflex on the right. When she is asked to protrude her tongue, it deviates to the left, and the muscle in the left side of the tongue shows considerable atrophy. Which of the following labeled areas in the transverse sections of the brain stem is most likely damaged?
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55.
A placebo-controlled clinical trial is conducted to assess whether a new antihypertensive drug is more effective than standard therapy. A total of 5000 patients with essential hypertension are enrolled and randomly assigned to one of two groups: 2500 patients receive the new drug and 2500 patients receive placebo. If the alpha is set at 0.01 instead of 0.05, which of the following is the most likely result?
(A) Significant findings can be reported with greater confidence (B) The study will have more power (C) There is a decreased likelihood of a Type II error (D) There is an increased likelihood of statistically significant findings (E) There is an increased likelihood of a Type I error
A 32-year-old woman and 31-year-old man come to the physician for preconceptional counseling. The man's brother recently started dialysis for polycystic kidney disease at age 42 years. Analysis of the man's urine shows 2+ blood and 10- 20 RBC/hpf. Ultrasonography shows multiple cysts in both kidneys. Which of the following best represents the likelihood that this couple will have a child who will develop polycystic kidney disease?
(A) 0% (B) 25% (C) 33% (D) 50% (E) 66% (F) 75% (G) 100%
An investigator is studying the effect of the number of hours watching television (Factor A) on the percent of hemoglobin A 1c
1c , are compared. The results of the study indicate a correlation coefficient of +0.9. Which of the following graphs shown best corresponds to these results?
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58.
A 35-year-old man who works at a facility processing highly radioactive substances accidentally receives a high, whole-body dose of ionizing radiation estimated to be 1500 rads (15 gray). He dies 1 week later. At autopsy, histologic examination of the skin shows scattered, individual epidermal cells with shrunken, markedly eosinophilic cytoplasm and pyknotic, fragmented nuclei. These morphologic changes most likely indicate which of the following processes?
(A) Apoptosis (B) Coagulation necrosis (C) Liquefaction necrosis (D) Mutagenesis (E) Tumor initiation
59.
A 47-year-old woman comes to the emergency department because of a 2-week history of intermittent abdominal pain, nausea, and vomiting. She has had similar episodes sporadically during the past 4 years. Physical examination shows dehydration, jaundice, and upper abdominal distention. Laboratory studies show hyperbilirubinemia. A CT scan and upper gastrointestinal series of the abdomen with oral contrast are shown; the arrows indicate the abnormality. Which of the following is the most likely cause of these findings?
(A) Annular pancreas (B) Cirrhosis of the liver (C) Duodenal constriction by the portal vein (D) Duodenal constriction by the superior mesenteric artery (E) Pyloric stenosis
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60.
A 6-year-old boy is brought to the physician by his parents because of a 3-day history of fever, headache, and cough productive of a green, foul-smelling discharge that also exits from his nose. He has had repeated episodes of similar symptoms during the past 4 years. He appears pale and lethargic. His height and weight are both below the 10th percentile. Coarse rhonchi are heard bilaterally. An x-ray of the chest shows scattered peripheral opacities, dilated and thickened airways consistent with bronchiectasis, and a cardiac apex that is directed toward the right. The most likely cause of his recurrent infections is a dysfunction of which of the following cell types?
(A) Alveolar capillary endothelial cell (B) Alveolar macrophage (C) Chondrocyte (D) Ciliated columnar epithelial cell (E) Clara cell (F) Goblet cell (G) Kulchitsky cell (H) Squamous epithelial cell (I)
Type I pneumocyte (J) Type II pneumocyte
A 4-year-old boy is brought to the physician because of slow growth during the past year. He has had recurrent urinary tract infections since the age of 1 year. He is at the 10th percentile for height and 25th percentile for weight. Physical examination shows pallor. Laboratory studies show a normochromic, normocytic anemia and increased serum concentrations of urea nitrogen and creatinine. Urinalysis shows a low specific gravity. Which of the following sets of additional serum findings is most likely in this patient?
Inorganic Phosphorus 1,25-Dihydroxycholecalciferol Erythropoietin (A)
↑ ↑ ↑ ↓ (B)
↑ ↑ ↓ ↓ (C)
↑ ↓ ↓ ↑ (D)
↓ ↑ ↑ ↓ (E)
↓ ↑ ↓ ↓ (F)
↓ ↓ ↑ ↑
62.
A 14-year-old boy is brought to the physician for a physical examination prior to participating in sports. He appears reluctant to remove his shirt for the examination, and says that he is embarrassed because he has grown breasts during the past year. He is at the 50th percentile for height and weight. Physical examination shows bilateral 1.5-cm fibroglandular masses located beneath the nipple-areolar complex and normal penis and testes. Pubic hair development is Tanner stage 3. Serum concentrations of gonadotropic hormones, estrogens, and testosterone are within the reference ranges. Which of the following is the most likely cause of this patient's breast enlargement?
(A) Breast adenocarcinoma (B) Estradiol-secreting Leydig cell tumor (C) Peutz-Jeghers syndrome (D) Seminiferous tubule dysgenesis (Klinefelter syndrome) (E) Normal development
A 23-year-old woman with bone marrow failure is treated with a large dose of rabbit antithymocyte globulin. Ten days later, she develops fever, lymphadenopathy, arthralgias, and erythema on her hands and feet. Which of the following is the most likely cause of these symptoms?
(A) Cytokine secretion by natural killer cells (B) Eosinophil degranulation (C) Immune complex deposition in tissues (D) Polyclonal T-lymphocyte activation (E) Widespread apoptosis of B lymphocytes
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64.
A 31-year-old woman with type 2 diabetes mellitus comes to the physician because of an oozing, foul-smelling wound on her foot for 2 days. Physical examination shows a 4-cm, necrotizing wound with a purplish black discoloration over the heel. Crepitant bullae producing profuse amounts of serous drainage are seen. A Gram stain of a tissue biopsy specimen shows gram-positive rods. The causal organism most likely produces which of the following virulence factors?
(A) Endotoxin (B) Fimbriae (C) Pneumolysin (D) Polysaccharide capsule (E) α-Toxin
A 35-year-old man comes to the physician because of pain and swelling of his right arm where he scraped it on a tree branch 2 days ago. His temperature is 38.3°C (101°F). Examination of the right forearm shows edema around a fluctuant erythematous lesion at the site of trauma. The area is extremely tender to palpation. Which of the following is most likely the primary mechanism of the development of edema in this patient?
(A) Degranulation of eosinophils (B) Disruption of vascular basement membranes (C) Increased hydrostatic pressure (D) Release of thromboxane (E) Separation of endothelial junctions
A 6-month-old male infant is admitted to the hospital for treatment of bacterial pneumonia. Examination shows absence of B lymphocytes and surface immunoglobulins; there are minimal CD3+ T lymphocytes. An x-ray of the chest shows absence of the thymic shadow and a right lower lobe infiltrate. Which of the following is the most likely diagnosis?
(A) AIDS (B) Chronic granulomatous disease (C) DiGeorge syndrome (D) Severe combined immunodeficiency (E) X-linked agammaglobulinemia
A 64-year-old man with non-Hodgkin lymphoma comes to the physician because of a 3-week history of progressive numbness in his hands and feet and weakness in his legs when he stands. He received his third course of chemotherapy 4 weeks ago. Physical examination shows areflexia. Which of the following drugs is the most likely cause of these adverse effects?
(A) Bleomycin (B) Cyclophosphamide (C) Cytarabine (D) Doxorubicin (E) Fluorouracil (F) Methotrexate (G) Vincristine
A 45-year-old man has abnormal circadian variation in body temperature, disruption of the sleep-wake cycle, and an impaired nocturnal surge of secretion of melatonin. An MRI of the brain is most likely to show a lesion involving which of the following nuclei?
(A) Accessory optic (B) Lateral preoptic (C) Pretectal (D) Suprachiasmatic (E) Supraoptic
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69. Six healthy subjects participate in a study of muscle metabolism during which hyperglycemia and hyperinsulinemia is induced. Muscle biopsy specimens obtained from the subjects during the resting state show significantly increased concentrations of malonyl-CoA. The increased malonyl-CoA concentration most likely directly inhibits which of the following processes in these subjects?
(A) Fatty acid oxidation (B) Fatty acid synthesis (C) Gluconeogenesis (D) Glycogenolysis (E) Glycolysis (F) Oxidative phosphorylation
70.
After being severely beaten and sustaining a gunshot wound to the abdomen, a 42-year-old woman undergoes resection of a perforated small bowel. During the operation, plastic reconstruction of facial fractures, and open reduction and internal fixation of the left femur are also done. Thirty-six hours postoperatively, she is awake but not completely alert. She is receiving intravenous morphine via a patient-controlled pump. She says that she needs the morphine to treat her pain, but she is worried that she is becoming addicted. She has no history of substance use disorder. She drinks one to two glasses of wine weekly. Which of the following initial actions by the physician is most appropriate?
(A) Reassure the patient that her chance of becoming addicted to narcotics is minuscule (B) Maintain the morphine, but periodically administer intravenous naloxone (C) Switch the patient to oral acetaminophen as soon as she can take medication orally (D) Switch the patient to intramuscular lorazepam (E) Switch the patient to intravenous phenobarbital
71.
A 42-year-old woman is brought to the emergency department because of double vision that began 20 minutes after she fell from her horse and landed on the left side of her face. Examination of the face shows ecchymoses over the left zygomatic arch. A CT scan of the head is shown. Which of the following arteries is at greatest risk for injury in this patient?
(A) Facial (B) Frontal (C) Infraorbital (D) Lacrimal (E) Ophthalmic
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72.
A 17-year-old girl is brought to the physician by her mother because she has not had a menstrual period for 6 months. The patient is unconcerned about the lack of menses. Menarche occurred at the age of 12 years, and menses had occurred at regular 28-day intervals until they became irregular 1 year ago. She is a member of her high school gymnastics team. She appears emaciated. She is 163 cm (5 ft 4 in) tall and weighs 40 kg (88 lb); BMI is 15 kg/m 2 . Her pulse is 54/min, and blood pressure is 80/50 mm Hg. Which of the following is the most likely cause of this patient's amenorrhea?
(A) Hyperthyroidism (B) Hypogonadotropic hypogonadism (C) Hypothyroidism (D) Polycystic ovarian syndrome (E) Prolactinoma
A 26-year-old woman is brought to the emergency department because of an 8-hour history of severe back and abdominal pain and mild but persistent vaginal bleeding. Ultrasonography of the abdomen shows a 2-cm ectopic pregnancy in the ampulla. The ampulla has ruptured into the surrounding tissue. Fluid from this rupture will most likely be found in which of the following locations?
(A) Lesser peritoneal cavity (B) Mesometrium (C) Pouch of Douglas (D) Uterine cavity (E) Vagina
74.
A 30-year-old man is admitted to the hospital for evaluation. He has a 6-week history of colicky abdominal pain and diarrhea with occasional blood. Three days after admission, he suddenly develops peritonitis and sepsis. Despite appropriate care, he dies. At autopsy, examination shows a fibrinous exudate over the peritoneal and serosal surfaces, and a punctate opening is seen in the wall of a thickened loop of small intestine. Several lengths of the small and large intestines are also thickened and adherent to one another, with marked areas of narrowing. Photomicrographs of a section of the colon are shown. Which of the following is the most likely diagnosis?
(A) Colon cancer (B) Crohn disease (C) Diverticulitis (D) Ischemic necrosis (E) Ulcerative colitis
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75.
A 55-year-old man who is a business executive is admitted to the hospital for evaluation of abdominal pain. He is polite to the physician but berates the nurses and other staff. The patient's wife and two of his three adult children arrive for a visit. The patient says with disgust that the missing child is and always has been worthless. Which of the following is the most likely explanation for this patient's behavior?
(A) Countertransference (B) Projection (C) Projective identification (D) Reaction formation (E) Splitting
A patient being treated with clindamycin for aspiration pneumonia develops diarrhea. The stool contains a toxin that kills cultured epithelial cells. Stool culture grows an anaerobic gram-positive rod. The same organism is cultured from his bedpan. Which of the following is most likely to sterilize the bedpan?
(A) Boiling for 45 minutes (B) Exposure to benzalkonium chloride for 1 hour (C) Exposure to ethyl alcohol for 1 hour (D) Exposure to saturated steam (121°C) for 15 minutes (E) Heating in an oven at 150°C for 30 minutes
A 2-year-old boy is brought to the physician for a well-child examination. He was delivered at term after an uncomplicated pregnancy. His birth weight was 3500 g (7 lb 11 oz), and Apgar scores were 8 and 10 at 1 and 5 minutes, respectively. At the age of 15 months, physical examination showed no abnormalities, but he was not yet talking. Both of his parents had learning difficulties in school, and his mother stopped attending after the 10th grade. He has a maternal uncle with cognitive disabilities. He is at the 25th percentile for height, 15th percentile for weight, and 90th percentile for head circumference. He appears irritable, he resists making eye contact, and he is flapping his hands. Which of the following is the most likely cause of this patient's condition?
(A) Creation of an alternative splice site (B) Frameshift mutation (C) Missense mutation (D) Nonsense mutation (E) Trinucleotide repeat expansion
A 17-year-old boy is brought to the emergency department 30 minutes after being found with a "blank stare" and flat facial expression at a party. His pulse is 72/min, and blood pressure is 104/68 mm Hg. He is sitting upright and appears catatonic. Physical examination shows rigidity. During the examination, he becomes hostile and attempts to assault the physician. This patient most likely ingested which of the following drugs?
(A) Cocaine (B) Diazepam (C) Methamphetamine (D) Oxycodone (E) PCP (phencyclidine)
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79.
A 52-year-old man with a 15-year history of hypertension, type 1 diabetes mellitus, and hyperlipidemia comes to the physician because of a 2-month history of shortness of breath. He underwent coronary artery bypass grafting 5 years ago. His pulse is 90/min, respirations are 22/min, and blood pressure is 160/86 mm Hg. Jugular venous pressure is 20 cm H 2 O. There are crackles bilaterally halfway up the chest. Cardiac examination shows a grade 2/6 holosystolic murmur and an S 3 gallop at the apex. Which of the following is most likely to be helpful in establishing the most appropriate treatment at this time?
(A) Assessment of blood pressure readings over the past 2 years (B) Determination of hemoglobin A 1c
(C) Evaluation of left ventricular ejection fraction (D) Measurement of fasting serum cholesterol concentration (E) Review of the operative report of the bypass surgery
80.
A previously healthy 40-year-old man is brought to the emergency department because of constant substernal chest pain for 12 hours that is exacerbated by coughing and inspiration. The pain is relieved with sitting up and leaning forward. There is no family history of heart disease. His temperature is 38°C (100.4°F), pulse is 120/min, and blood pressure is 110/60 mm Hg. The lungs are clear to auscultation. Cardiac examination shows distant heart sounds. An ECG shows diffuse ST-segment elevation in all leads. An x-ray of the chest shows normal findings. The most likely cause of his condition is injury to which of the following tissues?
(A) Aortic intima (B) Esophageal sphincter (C) Myocardium (D) Pericardium (E) Pleura
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USMLE STEP 1 SAMPLE TEST QUESTIONS
81.
A 20-year-old woman comes to the physician because of a 5-year history of heavy bleeding with menses that often requires her to change her sanitary pads three times hourly. Menses occur at regular 28-day intervals. She recently sustained a minor cut to her finger, and the bleeding took longer to stop than usual. She has not had easy bruising or change in weight. She only takes an oral contraceptive, but she has not been sexually active for the past 6 months. Her temperature is 37.5°C (99.5°F), pulse is 72/min, respirations are 12/min, and blood pressure is 120/66 mm Hg. Physical examination shows mildly pale conjunctivae. Pelvic examination shows no abnormalities. Laboratory studies show:
Hemoglobin 10.5 g/dL Hematocrit 31.3% Mean corpuscular hemoglobin concentration 28% Hb/cell Mean corpuscular volume 70 μm 3
Leukocyte count 5500/mm
3
Platelet count 275,000/mm 3
Platelet aggregation studies normal
Prothrombin time 10.5 sec (INR=1.0) Partial thromboplastin time 28 sec
A Pap smear shows no abnormalities. Which of the following hematologic disorders is the most likely cause of this patient's menorrhagia?
(A) Afibrinoginemia (B) Hemophilia A (C) Intravascular coagulation (D) Vitamin K deficiency (E) von Willebrand disease
A 40-year-old woman comes to the physician because of a 6-month history of increased facial hair growth. Her last menstrual period was 4 months ago. She is 165 cm (5 ft 5 in) tall and weighs 70 kg (154 lb); BMI is 26 kg/m 2 . Her pulse is 80/min, and blood pressure is 130/82 mm Hg. Physical examination shows temporal balding and coarse dark hair on the upper lip and chin. Pelvic examination shows clitoral enlargement. Her serum testosterone concentration is increased. Serum concentrations of androstenedione, dehydroepiandrosterone, and urinary 17-ketosteroids are within the reference ranges. Ultrasonography of the pelvis shows a 12-cm ovarian mass. Which of the following best describes this mass?
(A) Granulosa tumor (B) Ovarian carcinoid (C) Sertoli-Leydig tumor (D) Teratoma (E) Thecoma
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83.
A 35-year-old man who recently immigrated to the USA from Mexico comes to the physician because of a 6-month history of lesions on his face and chest. He has a history of asthma and atopic dermatitis. Physical examination shows the findings in the photograph. Which of the following cytokines is most likely to be increased in these lesions?
(A) Interferon gamma (B) Interleukin-4 (IL-4) (C) IL-12 (D) Transforming growth factor (TGF)-α (E) TGF-β
A 45-year-old woman with systemic sclerosis (scleroderma) comes to the physician because of a 3-week history of progressive shortness of breath and nonproductive cough. Her temperature is 36.9°C (98.4°F), pulse is 82/min, respirations are 20/min, and blood pressure is 136/85 mm Hg. Crackles are heard in both lower lung fields. Pulmonary function tests show total lung capacity is 80% of predicted, and diffusing capacity for carbon monoxide, corrected for alveolar volume, is 65% of predicted. Histologic examination of a lung biopsy specimen is most likely to show which of the following findings?
(A) Diffuse interstitial fibrosis (B) Intra-alveolar exudates (C) Multiple thromboemboli (D) Necrotizing vasculitis (E) Non-necrotizing interstitial granulomas
A 52-year-old man comes to the emergency department because he has had vomiting, nausea, and abdominal pain for the past 12 hours. He says he attempted suicide 3 days ago by "taking everything in the medicine cabinet." He was stuporous for approximately 12 hours after the overdose but felt better the following day. At this time, he has jaundice and pain in the right upper quadrant. Which of the following drugs is most likely to have caused the pain, vomiting, and jaundice?
(A) Acetaminophen (B) Aspirin (C) Cimetidine (D) Diphenhydramine (E) Triazolam
In a cohort study of elderly women, the relative risk ratio for hip fractures among those who exercise regularly is 1.2 (95% confidence interval of 1.1 to 1.8). Which of the following is the most appropriate conclusion about the effect of regular exercise on the risk for hip fracture?
(A) Statistically nonsignificant increase in risk (B) Statistically nonsignificant overall decrease in risk (C) Statistically significant overall decrease in risk (D) Statistically significant overall increase in risk
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87. A study is designed to evaluate the feasibility of acupuncture in children with chronic headaches. Sixty children with chronic headaches are recruited for the study. In addition to their usual therapy, all children are treated with acupuncture three times a week for 2 months. Which of the following best describes this study design?
(A) Case-control (B) Case series (C) Crossover (D) Cross-sectional (E) Historical cohort (F) Randomized clinical trial
88.
A 52-year-old woman is admitted to the hospital because of breast cancer metastatic to the liver. Her prognosis is poor. She begs her husband to stay with her at the hospital because she is afraid to be left alone. Which of the following defense mechanisms best explains her behavior?
(A) Denial (B) Displacement (C) Regression (D) Repression (E) Sublimation
A 42-year-old man comes to the physician for a follow-up examination 1 week after he passed a renal calculus. X-ray crystallographic analysis of the calculus showed calcium as the primary cation. Physical examination today shows no abnormalities. A 24-hour collection of urine shows increased calcium excretion. Which of the following is the most appropriate pharmacotherapy?
(A) Carbonic anhydrase inhibitor (B) Na + –Cl − symport inhibitor (C) Na +
+ –2Cl
− symport inhibitor (D) Osmotic diuretic (E) Renal epithelial sodium channel inhibitor
36
90.
A 67-year-old woman is brought to the emergency department 30 minutes after she had a generalized tonic-clonic seizure. Her family says that she seemed mildly confused before her eyes rolled backward and she had the onset of uncontrollable jerking movements of her arms and legs and loss of consciousness. During the seizure, she passed urine and bit her tongue. At the scene, her vital signs were within normal limits. She has a 6-month history of a 7-kg (15-lb) weight loss despite no changes in appetite. She received the diagnosis of small cell carcinoma of the lung last week and has not begun treatment. She has hypertension well controlled with lisinopril. On arrival, she is awake but does not respond to verbal stimuli. She is not in distress. Her temperature is 37°C (98.6°F), pulse is 70/min, and blood pressure is 130/88 mm Hg while supine. Examination shows no abnormalities. Laboratory studies show:
Serum Na
+
115 mEq/L K +
4 mEq/L Cl
−
81 mEq/L HCO 3 − 25 mEq/L Urea nitrogen 9 mg/dL
Glucose 102 mg/dL Creatinine 0.6 mg/dL Urine
60 mEq/L Potassium 20 mEq/L Osmolality 900 mOsmol/kg H 2 O Which of the following is the most likely diagnosis?
(A) Adrenal insufficiency (B) Diuretic abuse (C) Heart failure (D) Syndrome of inappropriate secretion of ADH (vasopressin) (E) Water intoxication
A 15-year-old girl comes to the physician because of a 3-month history of acne. Breast and pubic hair development began at the age of 12 years. Menarche occurred at the age of 14 years. Physical examination shows scattered open and closed comedones over the cheeks and forehead. Breast and pubic hair development are Tanner stage 5. Which of the following is the most likely underlying cause of this patient's acne?
(A) Decreased parasympathetic stimulation to the sebaceous glands (B) Increased estrogen stimulation of the sebaceous glands (C) Increased responsiveness of the sebaceous glands to follicle-stimulating hormone (D) Increased sympathetic stimulation to the sebaceous glands (E) Stimulation of the sebaceous glands by androgens
A 20-year-old man with a history of intermittent asthma comes to the physician because of a 1-week history of chest tightness, wheezing, malaise, and a cough productive of clear sputum. He does not appear to be in distress. His pulse is 72/min, respirations are 14/min, and blood pressure is 120/70 mm Hg. Physical examination shows clear tympanic membranes and no exudates in the oral pharynx. Diffuse expiratory wheezes are heard on auscultation. When asked to take a deep breath, the patient coughs with forced expiration. Which of the following substances is most appropriate to treat this patient's cough at this time?
(A) Albuterol (B) Dextromethorphan (C) Guaifenesin (D) Pseudoephedrine (E) Theophylline
37
93.
A 62-year-old man comes to the physician for a follow-up examination after he was diagnosed with chronic inflammatory interstitial pneumonitis. Following pulmonary function testing, a biopsy specimen of the affected area of the lungs is obtained. Compared with a healthy man, analysis of this patient's biopsy specimen is most likely to show which of the following patterns of changes in the cell populations of alveoli?
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