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    <1>A 61-year-old woman with leukemia abruptly develops an intensely
    itchy rash. Physical examination demonstrates multiple erythematous
    patches of the distal arms and legs, some of which involve the palms
    and soles. Some of the patches show central clearing with surrounding
    erythematous rings. Which of the following is the most likely diagnosis?
    A. Erythema migrans chronicum
    B. Erythema multiforme
    C. Kaposi's sarcoma
    D. Psoriasis
    E. Urticaria
    <2>A 52-year-old woman presents to her physician for a check-up. She is
    recovering from a wrist fracture after a fall. Dual energy x-ray
    absorptiometry of the hip had shown her to have osteoporosis. She
    became menopausal at age 50 and did not begin hormone replacement
    therapy because of a strong family history of breast cancer. She
    now fears a future hip fracture and would like to begin a bone
    loss prevention regime.Which of the following pharmaceutical
    agents is most appropriate for this patient?
    A. Calcitonin nasal spray
    B. Oral conjugated estrogen
    C. Raloxifene
    D. Tamoxifen
    E. Transdermal estradiol

    <3>A fracture of the humerus neck damages a nerve running around the humera
    l neck. After the fracture heals, the patient notices a marked decrease in
    his ability to raise his arm over his head. The denervated muscle arises
    from which of the following?
    A. Acromion alone
    B. Clavicle and acromion
    C. Clavicle and coracoid
    D. Coracoid alone
    E. Coracoid and acromion
    <4>A patient is admitted to a psychiatric hospital after having been picked
    up by the police for making inappropriate sexual advances. A detailed
    psychiatric interview demonstrates deficits in memory, insight,
    judgement, personal appearance, and social behavior. The patient
    is witnessed experiencing a possible epileptic seizure. Over a
    period of several years, motor findings also develop, including
    relaxed, but expressionless facies, tremor, dysarthria, and pupillary
    abnormalities. Which of the following tests performed on his
    cerebrospinal fluid would most likely be diagnostic?
    A. CSF glucose
    B. FTA-ABS
    C. Gram's stain
    D. Lymphocyte count
    E. Neutrophil count

    5.A 42-year-old man has just been informed that he has poorly
    differentiated small cell carcinoma of the lung. When asked if he
    understands the serious nature of his illness, the patient proceeds
    to tell his physician how excited he is about renovating his home.
    This patient is exhibiting
    A. denial
    B. displacement
    C. projection
    D. rationalization
    E. reaction formation
    F. sublimation

    <6>A 3-month-old infant presents with a 3-day history of fever, cough,
    and poor feeding. On examination, the baby appears ill and has a
    temperature of 102 F and a respiratory rate of 32. A chest x-ray
    film shows bilateral patchy infiltrates in the lungs. Which of
    the following is the most likely etiologic agent?
    A. Coronavirus
    B. Influenza type A
    C. Parainfluenza type 1
    D. Respiratory syncytial virus
    E. Rhinovirus
    <7>A 35-year-old male presents to the urologist for an infertility
    evaluation. A biopsy of his testis is performed to check sperm production
    and maturation. A microscopic section reveals only a few germ cells near
    the basal lamina in the seminiferous tubule. Which of the following cells
    is the germ cell closest to the basal lamina in the seminiferous tubule?
    A. Primary spermatocyte
    B. Secondary spermatocyte
    C. Spermatid
    D. Spermatogonia
    E. Spermatozoa
    <8>A 30-year-old otherwise healthy woman presents to her physician with
    complaints of fatigue and dyspnea. Physical examination reveals normal
    breath sounds and the presence of third and fourth heart sounds. Chest
    x-ray shows clear lung fields but right ventricular enlargement, main
    pulmonary artery enlargement, and "pruning" of the peripheral vasculature.
    Electrocardiogram shows right axis deviation and right ventricular
    hypertrophy. Left ventricular function appears normal on echocardiography
    . Serologic studies show antinuclear antibodies. Which of the following
    pathological findings would this patient also show, either at autopsy
    or if an appropriate biopsy was taken?
    A. Mural thrombus of the right atrium
    B. Necrosis and scarring of the left ventricle
    C. Plexogenic pulmonary vasculopathy
    D. Pulmonary artery stenosis
    E. Severe pulmonary fibrosis
    <9>During an abdominal surgical procedure, the surgeon wishes to locate the
    ureter in order to ensure that it is not injured. The ureter may be found
    immediately anterior to the origin of the
    A. common iliac artery
    B. external iliac artery
    C. internal iliac artery
    D. gonadal artery
    E. renal artery
    <10>A patient with mild congestive heart failure is treated with high-dose
    furosemide and diureses 25 pounds of fluid. A complete blood count (CBC)
    taken before the diuresis shows an RBC count of 4 million/mm3; a
    CBC taken after diuresis shows a RBC count of 7 million/mm3.
    Which of the following is the most likely explanation?
    A. Cyanotic heart disease
    B. Increased erythropoietin
    C. Polycythemia vera
    D. Relative polycythemia
    E. Renal cell carcinoma
    <11>A newborn male child is noted to have hypospadias. A complete
    evaluation determines that the child has no other genitourinary
    anomalies. Nonetheless, hypospadias repair will be performed to
    prevent which of the following possible sequelae?
    A. Bladder exstrophy
    B. Hydrocele
    C. Phimosis
    D. Urachal cysts
    E. Urinary tract infection
    <12>During the passage of an intravenous catheter, numerous endothelial
    cells are dislodged from the lining of the popliteal vein. What substance
    allows platelet adhesion to the exposed collagen fibers?
    A. Factor VIII
    B. Factor IX
    C. Fibronectin
    D. Tissue factor
    E. Von Willebrand factor
    <13>A 57-year-old man presents to the emergency department with a nosebleed
    for the past 2 hours. The patient received a prosthetic heart valve 5
    months ago and is currently taking warfarin (7.5 mg per day) and oral
    antibiotics. Laboratory evaluation reveals an INR (international
    normalized ratio, the ratio of patient to normal prothrombin times)
    of 6.4. Which of the following antibiotics is the patient most likely
    A. Ampicillin
    B. Cephalexin
    C. Nitrofurantoin
    D. Norfloxacin
    E. Phenazopyridine
    <14>A 47-year-old woman presents with complaints of nervousness and
    increased sensitivity to hot weather. She is diagnosed with hyperthyroidism
    and prescribed propylthiouracil. What is the principal mechanism by which
    this drug acts?
    A. Decreasing the efficacy of TSH binding to the thyroid TSH receptor
    B. Decreasing the rate of proteolysis of thyroglobulin
    C. Increasing the amount of 3,3',5'-triiodothyronine (reverse T3; rT3)
    D. Inhibiting deiodination of thyroxine (T4)
    E. Inhibiting the uptake of iodide into the thyroid gland
    <15>Which of the following neurotransmitters is most important for the
    induction of REM sleep?
    A. Acetylcholine
    B. Dopamine
    C. Epinephrine
    D. Norepinephrine
    E. Serotonin
    <16>A 37-year-old woman presents with 3 days of progressive joint pain in
    her ankles, knees, and wrists. She had three similar episodes over the
    past several years. On examination, she has a temperature of 38.7 C, her
    blood pressure is 110/70 mm Hg, and her heart rate is 90/min. She has a
    diffuse petechial rash over her trunk and extensor surfaces. Her ankles
    and knees are swollen, red, and tender with decreased range of motion,
    and there is tenderness over the tendon sheaths of her hands and
    forearms. Blood cultures are negative. Aspiration of joint fluid
    reveals a white cell count of 22,000/mm3 with no visible organisms,
    but culture on chocolate agar is positive. Which of the following
    is an attribute of the causative organism that allows it to produce
    recurrent infections?
    A. It is an intracellular pathogen
    B. It is resistant to ceftriaxone
    C. It is resistant to complement-mediated lysis
    D. Its capsule is not immunogenic
    E. Its pili undergo antigenic and phase variation
    <17>The data presented below compares the results of a diagnostic test in
    the presence and absence of a disease.
    Disease present Disease absent
    Positive test 40 5
    Negative test 10 95
    Total 50 100
    The specificity of the test is
    A. 0.05
    B. 0.40
    C. 0.80
    D. 0.90
    E. 0.95
    <18>Blood stored in a blood bank tends, with time, to become relatively
    depleted of 2,3-diphosphoglycerate. What effect does this have on the
    hemoglobin-oxygen dissociation curve?
    A. Shifts the curve to the left, so that the hemoglobin has a decreased oxygen affinity
    B. Shifts the curve to the left, so that the hemoglobin has an increased oxygen affinity
    C. Shifts the curve to the right, so that the hemoglobin has a decreased oxygen affinity
    D. Shifts the curve to the right, so that the hemoglobin has
    an increased oxygen affinity
    E. Does not change the dissociation curve
    <19>A psychotic, indigent man with a history of multisubstance abuse has
    been involuntarily hospitalized for 1 week. Because of persistent diarrhea,
    stools are sent for ova and parasites, revealing numerous granular,
    spherical, thin-walled cysts measuring 10-20 mm in diameter. Trichrome
    stains show up to four nuclei in most of the cysts. These finding are
    consistent with an infection by which of the following organisms?
    A. Cryptosporidium parvum
    B. Dientamoeba fragilis
    C. Entamoeba histolytica
    D. Giardia lamblia
    E. Isospora belli
    <20>A child who understands that the volume of a liquid poured out of a
    narrow glass remains the same when poured into a wider glass is at which
    of Piaget's stages of intellectual development?
    A. Concrete operations
    B. Formal operations
    C. Preoperational
    D. Sensorimotor
    <21>A 4-year-old girl is brought to a specialty clinic by her foster parents
    because of a limp in her right leg and a serum alkaline phosphatase (ALP)
    that is 10 times the adult upper limit of normal for the test. The child
    is withdrawn and clinging to her foster mother. Physical examination is
    remarkable for a blue-green discoloration of the skin overlying a
    tender, 3-cm mass on the anterior portion of the right mid-thigh.
    An x-ray of the right thigh reveals a dense mass within the femur
    that extends into the surrounding tissue. Which of the followin
    best describes the increased alkaline phosphatase and physical
    findings in this case?
    A. ALP is abnormal for her age and the bone lesion represents an area of aseptic necrosis
    B. ALP is abnormal for her age and the bone lesion represents repair of a femoral fracture
    C. ALP is abnormal for her age and is unrelated to the bone lesion
    D. ALP is normal for her age and the bone lesion is an osteogenic sarcoma
    E. ALP is normal for her age and is unrelated to the bone lesion
    <22>Which of the following drugs antagonizes both the vascular and cardiac
    actions of norepinephrine?
    A. Atenolol
    B. Esmolol
    C. Labetalol
    D. Metaproterenol
    E. Prazosin
    <23>During surgery to treat an ischioanal abscess, the inferior rectal nerve
    is damaged. This nerve is a direct branch of which of the following nerves?
    A. Inferior gluteal nerve
    B. Pelvic splanchnic nerve
    C. Pudendal nerve
    D. Sciatic nerve
    E. Superior gluteal nerve
    <24>A 15-year-old girl is evaluated for failure to begin menstruation.
    Physical examination demonstrates short stature and a webbed neck.
    Chromosomal analysis demonstrates a lack of one X chromosome. This
    patient should be specifically evaluated for which of the following
    cardiovascular anomalies?
    A. Coarctation of the aorta
    B. Dextrocardia
    C. Ostium primum septal defect
    D. Pulmonary stenosis
    E. Tetralogy of Fallot
    <25>A baby is born with a testicular mass. Histologic sections made of the
    homogeneous yellow-white mass after its removal demonstrate
    epithelial-lined spaces that have flattened-to-cuboidal epithelial
    cells with vacuolated cytoplasm containing eosinophilic, hyaline-like
    globules. Scattered structures resembling primitive glomeruli (endodermal
    sinuses) are also seen. If appropriate immunohistochemical stains are
    performed, the eosinophilic cytoplasmic globules would most likely
    contain which of the following?
    A. Alpha-fetoprotein
    B. Estrogen receptors
    C. Human chorionic gonadotropin
    D. Human papilloma virus
    E. Melanin
    <26>A surgeon wishes to perform a splenectomy on a patient who has been in
    an automobile accident. Before removing the spleen, the splenic artery and
    splenic vein are ligated. Within which of the following peritoneal
    structures are the splenic artery and vein found?
    A. Gastrocolic ligament
    B. Gastrosplenic ligament
    C. Lesser omentum
    D. Splenorenal ligament
    <27>A 65-year-old woman with a long-standing disease has bone marrow
    fibrosis and increased bone remodeling, with bone resorption exceeding
    bone formation. She has a history of passing calcium-oxalate kidney
    stones. Which of the following lab result profiles would be expected in
    the serum of this patient?
    Calcium Phosphate PTH
    A. decreased decreased increased
    B. decreased increased decreased
    C. decreased increased increased
    D. increased decreased increased
    E. increased increased increased
    <28>Upon examination of a newborn male, a cystic structure is found in the
    scrotum. It is determined that there is a hydrocele of the spermatic
    cord. Which of the following is the most likely etiology of this finding?
    A. Communication between the epididymis and the tunica
    B. Failure of the processus vaginalis to form
    C. Failure of the processus vaginalis to fuse
    D. Incomplete fusion of the processus vaginalis
    E. Varicosities of the spermatic vein
    <29>A Brazilian immigrant is hired at a meat-packing plant, and undergoes
    an employment physical. Chest x-ray demonstrates a patchy, bilateral
    pneumonia and a lung mass, and he is referred to a specialist. Biopsy
    of the mass demonstrates fungal organisms with a few very
    distinctive "pilot's wheel" yeast forms. Which of the following
    is the most likely diagnosis?
    A. Blastomycosis
    B. Coccidioidomycosis
    C. Histoplasmosis
    D. Paracoccidioidomycosis
    E. Sporotrichosis
    <30>A 34-year-old female is brought to the emergency room with severe
    muscle cramps and carpopedal spasms. The patient was noted to be
    extremely irritable and was complaining of tingling around the
    mouth and in the hands and feet. A few hours later, laboratory
    examination reveals sodium 140 mEq/L, potassium 4.2 mEq/L,
    chloride 101 mEq/L, calcium 6.4 mg/dL, phosphate 5.1 mg/dL,
    magnesium 2.4 (normal 1.8-3.8 mg/dL) and alkaline phosphatase
    67 U/L. A CT scan of the head shows basal ganglia calcifications.
    Prolonged QT intervals and T wave abnormalities are noted on
    electrocardiogram. The history is pertinent for a thyroidectomy
    two months prior to admission. Which of the following conclusions
    is most consistent with these data?
    A. An increase in dietary vitamin D is warranted
    B. Hepatocytes have a low 25-hydroxylase activity
    C. Intestinal cells are underexpressing calcium transporter genes
    D. Isolated cells from the kidney have high 1-hydroxylase activity
    E. The levels of 1,25-dihydroxy vitamin D are normal
    <31>A 48-year-old man presents to his physician with complaints of
    dizziness and fatigue. Physical examination reveals a blood pressure
    of 130/50 mm Hg and a heart rate of 100 beats per minute. On examination,
    the physician notes a large scar on the patient's abdomen. The man states
    that he was severely injured in an automobile accident several years ago,
    and required abdominal surgery at that time. Which of the following is
    the most likely diagnosis?
    A. Arteriovenous fistula
    B. Cardiac tamponade
    C. Heart failure
    D. Hypovolemia
    E. Shock
    <32>A renal pathologist examining the day's kidney biopsies notes that one
    biopsy shows amorphous red nodules within the glomerular mesangium in
    hematoxylin and eosin stained material. Congo red stain of the biopsy
    demonstrates apple-green birefringence of these nodules. These nodules
    are most likely to be related to which of the following?
    A. Acute urinary tract infection
    B. Diabetes mellitus
    C. Sarcoidosis
    D. Systemic lupus erythematosus
    E. Tuberculosis
    <33>A patient goes to his family doctor complaining of persistent and severe
    headaches. His physician diagnoses migraine headaches and prescribes
    sumatriptan. What is the mechanism of action of this drug?
    A. Dopamine1 agonist
    B. GABAB antagonist
    C. Muscarinic3 antagonist
    D. Non-selective beta antagonist
    E. Serotonin1D agonist
    <34>A 60-year-old man presents to his physician after a routine screening
    test indicates hyperlipidemia. Physical examination reveals raised,
    irregular, yellow papules in the skin of the soft tissues below the
    eyes. Biopsy of these lesions would most likely show which of the
    A. Benign nevus cells
    B. Malignant nevus cells
    C. Microscopic blisters
    D. Munro microabscesses
    E. Multinucleated giant cells
    <35> Trisomy 21 Normal karyotype
    Positive test 100 50
    Negative test 100 250
    An experimental diagnostic test is developed to noninvasively detect the
    presence of trisomy 21, Down's syndrome. The test is administered to a
    group of 500 women considered to be at risk for a Down's fetus based
    on blood tests. The results of this test are shown above. What is
    the sensitivity of this new test?
    A. 40%
    B. 50%
    C. 67%
    D. 71%
    E. 83%
    <36>An autopsy is performed on a 60-year-old man who developed progressive
    dementia, parkinsonism, and visual hallucinations beginning 5 years prior
    to death. Histopathologic examination reveals numerous eosinophilic
    intracytoplasmic inclusions within neurons of substantia nigra,
    limbic cortex, and basal nucleus of Meynert. These inclusions are
    immunoreactive for ubiquitin. Which of the following is the most
    likely postmortem diagnosis?
    A. Alzheimer disease
    B. Amyotrophic lateral sclerosis (ALS)
    C. Diffuse Lewy body disease (dementia with Lewy bodies)
    D. Parkinson disease
    E. Pick disease
    <37>A 60-year-old factory worker reports to his physician that he can no
    longer push heavy boxes across the floor. Upon examination it is noted
    that the patient elevates the right shoulder when attempting shoulder
    flexion, but shoulder abduction is not impaired. The medial border of
    the right scapula is very prominent. Which of the following nerves
    innervates the affected muscle?
    A. Long thoracic nerve
    B. Lower subscapular nerve
    C. Musculocutaneous nerve
    D. Suprascapular nerve
    E. Upper subscapular nerve
    <38>The American Diabetes Association (ADA) recently lowered the cutoff
    value for fasting glucose used in diagnosing diabetes mellitus from 140
    mg/dL to 126 mg/dL. This reference interval change would be expected to
    produce which of the following alterations?
    A. Decrease the test's sensitivity
    B. Increase the test's false negative rate
    C. Increase the test's negative predictive value
    D. Increase the test's positive predictive value
    E. Increase the test's specificity
    <39>An emergency room physician examines a patient who has fallen from a
    motorcycle and injured his shoulder. The clinician notices a loss of the
    normal contour of the shoulder and a abnormal-appearing depression below
    the acromion. Which of the following injuries did the patient most likely
    A. Avulsion of the coronoid process
    B. Dislocated shoulder joint
    C. Fracture of the mid shaft of the humerus
    D. Fracture of the surgical neck of the humerus
    E. Laceration of the axillary branch of the posterior cord
    <40>A 7-month-old child with failure to thrive is found to have a hemoglobin
    of 4.4 g/dL. The peripheral smear shows very small red cells with marked
    pallor. It is determined that the child has very low levels of hemoglobin
    A, with elevated fractions of hemoglobin A2 and hemoglobin F. Which of
    the following underlying mechanisms is most likely related to the
    observed findings?
    A. Amino acid substitution on b globin
    B. Antibody against fetal blood cells
    C. Cytoskeletal protein defect
    D. Insufficient production of b globin
    E. Iron deficiency
    <41>During a routine pelvic examination, a 20-year-old woman is found to
    have an enlarged uterus. Ultrasound studies demonstrate a multiloculated
    cystic structure within the uterine cavity, but no baby is identified.
    This mass is removed with dilation and curettage of the uterus, and
    placental-like tissue is observed during pathologic examination.
    Which of the following tumor markers would be most useful in
    establishing that residual tumor does not remain in the uterus?
    A. b-hCG
    B. Bombesin
    C. CEA
    D. PSA
    E. S-100
    <42>On physical examination of a 7-year-old boy, the child's upper body
    appears much more developed than his lower body. Blood pressure in the
    upper extremities exceeds that of the lower extremities. On cardiac
    examination, there is a midsystolic murmur over the anterior chest
    and back. The child's lower extremities are cold, and femoral pulses
    are absent. The part of the vascular system that is affected in this
    disorder is derived from which of the following embryologic structures?
    A. Bulbus cordis
    B. Ductus arteriosus
    C. Left horn of sinus venosus
    D. Right common cardinal vein
    E. Right horn of sinus venosus
    F. Third, fourth, and sixth aortic arches
    <43>A 42-year-old obese woman experiences episodic abdominal pain. She notes
    that the pain increases after the ingestion of a fatty meal. The action of
    which of the following hormones is responsible for the postprandial
    intensification of her symptoms?
    A. Cholecystokinin
    B. Gastrin
    C. Pepsin
    D. Secretin
    E. Somatostatin
    <44>A 42-year-old man was in an automobile accident and suffered severe
    pelvic trauma. The bulb of the penis and the urethra were torn from the
    inferior surface of the urogenital diaphragm. This has allowed urine to
    extravasate from the urethra. Into which of the following regions will
    the urine flow?
    A. Deep perineal space
    B. Ischioanal space
    C. Rectovesical pouch
    D. Retroperitoneal space
    E. Superficial perineal space

    <45>Karyotypic analysis of a spontaneously aborted fetus demonstrates
    trisomy of one of the chromosomes. Which chromosome is most likely to
    be affected?
    A. 8
    B. 13
    C. 16
    D. 18
    E. 21

    <46>At which of the following locations might a penetrating wound to the
    heart damage the AV node?
    A. Apex of the heart
    B. Interatrial septum
    C. Interventricular septum
    D. Wall of the right atrium
    E. Wall of the left atrium
    <47>A 9-month-old infant is brought to the Health Department to receive the
    second dose of OPV (oral polio vaccine) 2 weeks after the first vaccination.
    The child has mild diarrhea, so the decision is made to defer further
    immunizations. Bacteriologic examination of a stool culture is
    unremarkable; however, a small, single-stranded, positive RNA
    virus is isolated from the specimen. This same agent was
    isolated from sewage effluent the preceding week. The
    viral isolate was not inactivated by ether. Which of
    the following viruses was most likely isolated?
    A. Adenovirus
    B. Hepatitis C
    C. Parvovirus B19
    D. Poliovirus
    E. Rotavirus
    <48> Section of synovium from the knee joint of a patient with rheumatoid arthritis (RA) is taken. Which of the following are
    the most abundant cells in the inflammatory infiltrate?
    A. Eosinophils
    B. Langhans type giant cells
    C. Lymphocytes and plasma cells
    D. Neutrophils
    E. Type A and B synovial cells

    <49>A 54-year-old African-American female patient undergoes a routine
    insurance physical examination. Chest x-ray reveals bilateral hilar
    masses. Biopsy of the masses shows granulomata, but acid-fast and
    fungal stains are negative for organisms. Which of the following
    diseases should be suspected?
    A. Caroli's disease
    B. Raynaud's disease
    C. Sarcoidosis
    D. Scleroderma
    E. Systemic lupus erythematosus
    <50>A neuroscientist discovers a way to selectively label neural crest
    cells in a developing laboratory animal. After birth, he sacrifices the
    animal and examines the tissue to search for labeled cells. Which of
    the following cell types will contain the label?
    A. Astrocytes
    B. Ependymal cells
    C. Microglia
    D. Oligodendroglia
    E. Pseudounipolar cells

    1>B 11>E 21>*** 31>A 41>A
    2>*** 12>*** 22>C 32>*** 42>*** 23> 33> 43> C
    3>*** 13>D 23>*** 33>E 43>A
    4>*** 14>E 24>A 34>*** 44>***
    5>A 15>*** 25>*** 35>B 45>C
    6>D 16>C 26>B 36>C 46>B
    7>D 17>E 27>*** 37>A 47>D
    8>C 18>B 28>*** 38>C 48>C
    9>B 19>C 29>D 39>B 49>C
    10>D 20>A 30>*** 40>D 50>E

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