超星 - 逆转录病毒--章节练习

单选题

This HIV-positive patient with a viral load of 750,000 copies of HIV RNA/ml and a total CD4 count of 50 is at an increased risk for a number of infectious diseases. For which of the following diseases is the patient at no more added risk than an immunocompetent host?

A. Pneumocystic carinii pneumonia
B. Mycobacterial disease
C. Kaposi's sarcoma
D. Pneumococcal pneumonia

单选题

HIV-1 is classified as a member of the Lentivirus genus in the Retroviridae family. Lentiviruses

A. Contain a DNA genome
B. Cause tumors in mice
C. Infect cells of the immune system
D. Have related sequences endogenous in normal cells
E. Cause rapidly progressive neurologic diseas

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单选题

Each of the following statements concerning HIV is correct except

A. Screening tests for antibodies and nucleic acid are useful to prevent transmission of HIV through transfused blood
B. The opportunistic infections seen in AIDS are primarily the result of a loss of cell-mediated immunity
C. Zidovudine (azidothymidine) inhibits the RNA-dependent DNA polymerase
D. The presence of circulating antibodies that neutralize HIV is evidence that an individual is protected against HIV-induced disease

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单选题

Highly active antiretroviral therapy (HAART) is less than ideal because

A. It does not eliminate latent HIV infection
B. Some HIV strains are resistant to it
C. It often has severe side effects
D. All of the above

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单选题

The typical course of an untreated HIV infection extends over 10 or more years. There is usually a long period (clinical latency) between the time of primary HIV infection and the development of AIDS. During this period of clinical latency

A. HIV is not detectable in the plasma
B. CD4 cell counts remain unchanged
C. Virus replicates at a very low rate
D. Virus is present in lymphoid organs
E. Neutralizing antibodies are not elicited

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单选题

Retroviruses encode an enzyme called reverse transcriptase. The function of the reverse transcriptase enzyme is

A. DNase activity
B. RNA-dependent DNA polymerase activity
C. DNA-dependent RNA polymerase activity
D. RNA-dependent RNA polymerase activity

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单选题

A virus that causes human cancer is also associated with a nervous system disorder called tropical spastic paraparesis. That virus is

A. Polyomavirus JC
B. Polyomavirus SV40
C. Herpes simplex virus
D. Human T-lymphotropic virus

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单选题

A 42-year-old man is known to have HIV/AIDS. Which of the following is the most appropriate method to follow the progress of his highly active antiretroviral therapy (HAART)?

A. Determination of viral load
B. Following anti-HIV-1 antibody levels
C. Using Western blot to assess his anti-p24 levels
D. Repeated culture of his blood for HIV-1 to determine when the culture becomes negative

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单选题

A 36-year-old nurse suffered a needle stick with blood from an HIV-positive patient. Six months later, the nurse’s serum was positive in an EIA test, gave equivocal results in a repeat EIA test, and was negative by Western blot. The nurse

A. Is probably infected with HIV
B. Is in the window between acute infection with HIV and seroconversion
C. Is probably not infected with HIV
D. May be infected with a drug-resistant strain of HIV
E. May be a long-term nonprogressor

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单选题

A 41-year-old HIV-infected male who had refused antiretroviral therapy is diagnosed with Pneumocystis jiroveci (耶氏肺孢子菌) infection. This patient

A. Probably has a CD4 T-cell count below 200 cells/μL
B. Is at elevated risk for lung cancer
C. Is not longer a candidate for HAART
D. Probably has declining levels of plasma viremia
E. Is unlikely to develop dementia at this stage

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