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91.
The surgical hypertensive patient   总被引:1,自引:0,他引:1  
Foex  P; Sear  JW 《CEACCP》2004,4(5):139-143
We reviewed the pathophysiology and treatment of hypertensionin a recent edition of this journal (see key references). Inthis article, we discuss the management of the hypertensivepatient presenting for surgery and anaesthesia.  相似文献   
92.
Residual viral replication persists in a significant proportion of human immunodeficiency virus (HIV)-infected patients receiving potent antiretroviral therapy. To determine the source of this virus, levels of HIV RNA and DNA from lymphoid tissues and levels of viral RNA in serum, cerebrospinal fluid (CSF), and genital secretions in 28 patients treated for < or =2.5 years with indinavir, zidovudine, and lamivudine were examined. Both HIV RNA and DNA remained detectable in all lymph nodes. In contrast, HIV RNA was not detected in 20 of 23 genital secretions or in any of 13 CSF samples after 2 years of treatment. HIV envelope sequence data from plasma and lymph nodes from 4 patients demonstrated sequence divergence, which suggests varying degrees of residual viral replication in 3 and absence in 1 patient. In patients receiving potent antiretroviral therapy, the greatest virus burden may continue to be in lymphoid tissues rather than in central nervous system or genitourinary compartments.  相似文献   
93.
Understanding resistance to antiretroviral therapy plays an ever more crucial role in managing HIV infection as new agents - including several in new antiretroviral classes - promise better control of multidrug-resistant virus in the developed world. Yet these new drugs have different, and often complex, resistance profiles. At the same time, resistance has assumed a key role in developing countries as access to additional antiretrovirals expands in the face of first-line regimen failures. Every year the International HIV Drug Resistance Workshop gathers leading investigators and resistance-savvy clinicians to share unpublished, peer-reviewed research on the mechanisms, pathogenesis, epidemiology, and clinical implications of resistance to licensed and experimental antivirals. The 2007 workshop, held on 12-16 June, proved particularly notable for its exploration of resistance to two new antiretroviral classes, integrase inhibitors and CCR5 antagonists, as well as to agents that control hepatitis C virus (HCV) infection. This report summarizes most oral presentations from the workshop and many posters.  相似文献   
94.
A series of 29 madurahydroxylactone derivatives was evaluated for dual inhibition of human immunodeficiency virus type 1 (HIV-1) integrase and RNase H. While most of the compounds exhibited similar potencies for both enzymes, two of the derivatives showed 10- to 100-fold-higher selectivity for each enzyme, suggesting that distinct pharmacophore models could be generated. This study exemplifies the common and divergent structural requirements for the inhibition of two structurally related HIV-1 enzymes and demonstrates the importance of systematically screening for both integrase and RNase H when developing novel inhibitors.  相似文献   
95.
96.
BACKGROUND: The study objective was to compare the prognostic value of plasma HIV RNA and CD4 cell count at baseline and as time-updated variables in highly active antiretroviral therapy (HAART) users for two outcomes: development of AIDS and change in CD4 cell count. METHODS: The study population comprised 387 men enrolled in the Multicenter AIDS Cohort Study who were AIDS-free and initiated HAART between 1996 and 2001. Follow-up until AIDS diagnosis (n=36, 9%) or the last AIDS-free visit was included. To determine the predictive value of combining HIV RNA and CD4 cell count, regression tree methods using recursive partitioning at pre-specified cut points for both variables were used. RESULTS: Low CD4 cell count was a strong predictor of AIDS among HAART users. However, HIV RNA showed strong prognostic value for AIDS development among those with CD4 cell counts > 250 x 10(6) cells/l, in whom an HIV RNA level > 1000 copies/ml carried a 4.6-fold greater risk of developing AIDS. HIV RNA < 5000 copies/ml was also predictive of subsequent increase in CD4 cell count with significantly higher increases among those with initial CD4 counts > 300 x 10(6) cells/l. CONCLUSION: Although, in HAART users, CD4 cell count was the primordial prognostic marker, an HIV RNA > 1000 copies/ml attained after HAART initiation was a strong predictor of the rate of subsequent CD4 cell count increase and of developing AIDS in patients whose CD4 cell counts were > 250 x 10(6) cells/l.  相似文献   
97.
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts.  相似文献   
98.
SUMMARY Intracranial tuberculoma has become a rarity. It remains a curable lesion that responds well to medical therapy. Although diagnosis in developed countries is often made only postoperatively, early and effective treatment can be instituted if a high index of suspicion is maintained and diagnostic criteria are looked for. A case is presented which illustrates the difficulties in reaching a diagnosis, and a review of the literature is given.  相似文献   
99.
100.
Natural history of HIV-1 infection   总被引:4,自引:0,他引:4  
Infection with the human immunodeficiency virus type 1 (HIV-1) results in progressive loss of immune function marked by depletion of the CD4+ T-lymphocytes, leading to opportunistic infections and malignancies characteristic of AIDS. Although both host and viral determinants influence the rate of disease progression, the median time from initial infection to the development of AIDS among untreated patients ranges from 8 to 10 years. The clinical staging of HIV disease and the relative risk of developing opportunistic infections historically relied on the CD4+ T-lymphocyte counts. Although more recent studies have shown the importance of viral load quantitation in determining the rate of disease progression, it is still useful to categorize HIV disease stage on the basis of the degree of immunodeficiency: early disease (CD4+ > 500 cells/mL), mid-stage disease (CD4+ between 200 and 500 cells/mL), and end-stage disease (CD4+ < 50 cell/mL). This article reviews the natural history of HIV disease at each stage of HIV-1 infection with emphasis on acute infection and the major virologic and immunologic determinants of disease progression.  相似文献   
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