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101.
Nondisclosure of one’s HIV infection to sexual partners obviates safer sex negotiations and thus jeopardizes HIV transmission prevention. The role of alcohol use in the disclosure decision process is largely unexplored. This study assessed the association between alcohol use and recent nondisclosure of HIV serostatus to sex partners by HIV-infected risky drinkers in St. Petersburg, Russia. Approximately half (317/605; 52.4 %) reported not having disclosed their HIV serostatus to all partners since awareness of infection. Using three separate GEE logistic regression models, we found no significant association between alcohol dependence, risky alcohol use (past 30 days), or alcohol use at time of sex (past 30 days) with recent (past 3 months) nondisclosure (AOR [95 % CI] 0.81 [0.55, 1.20], 1.31 [0.79, 2.17], 0.75 [0.54, 1.05], respectively). Alcohol use at time of sex was associated with decreased odds of recent nondisclosure among seroconcordant partners and among casual partners. Factors associated with nondisclosure were relationship with a casual partner, a serodiscordant partner, multiple sex partners, awareness of HIV diagnosis less than 1 year, and a lifetime history of sexually transmitted disease. Nondisclosure of HIV status to sex partners is common among HIV-infected Russians, however alcohol does not appear to be a predictor of recent disclosure.  相似文献   
102.
From experiments with purified proteins, it has been concluded that factor XIa (FXIa) is inhibited in plasma mainly by alpha 1-antitrypsin (a1AT), followed by antithrombin III (ATIII), C1-inhibitor (C1Inh), and alpha 2-antiplasmin (a2AP). However, the validity of this concept has never been studied in plasma. We established the relative contribution of different inhibitors to the inactivation of FXIa in human plasma, using enzyme-linked immunosorbent assays (ELISAs) for the quantification of complexes of FXIa with a1AT, C1Inh, a2AP, and ATIII. We found that 47% of FXIa added to plasma formed complexes with C1Inh, 24.5% with a2AP, 23.5% with a1AT, and 5% with ATIII. The distribution of FXIa between these inhibitors in plasma was independent of whether FXIa was added to plasma, or was activated endogenously by kaolin, celite, or glass. However, in the presence of heparin (1 or 50 U/mL), C1Inh appeared to be the major inhibitor of FXIa, followed by ATIII. Furthermore, at lower temperatures, less FXIa-C1Inh and FXIa-a1AT complexes but more FXIa-a2AP complexes were formed. These data demonstrate that the contribution of the different inhibitors to inactivation of FXIa in plasma may vary, but C1Inh is the principal inhibitor under most conditions.  相似文献   
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Bone marrow disorders: characterization with quantitative MR imaging   总被引:10,自引:0,他引:10  
Smith  SR; Williams  CE; Davies  JM; Edwards  RH 《Radiology》1989,172(3):805-810
Thirty patients with various hematologic disorders and 15 healthy control subjects underwent quantitative magnetic resonance (MR) imaging of the lumbar spine with spin-echo techniques. Images of patients with infiltrative bone marrow disorders showed significantly more prolonged T1 times than those of control subjects (P less than .001). It was not possible to distinguish different diffuse infiltrative bone marrow disorders on the basis of T1 values. Aplastic anemia could be distinguished from normality because of significantly shortened T1 (P less than .001). A significant correlation was seen between T1 and bone marrow cellularity (r = .74, P less than .001). T2 was of no value in the characterization of bone marrow disorders. Quantitative MR imaging dose not improve the diagnostic potential of bone marrow imaging in the detection of diffuse marrow infiltrates.  相似文献   
106.
Temporal lobes: surface MR coil phased-array imaging   总被引:1,自引:0,他引:1  
Hayes  CE; Tsuruda  JS; Mathis  CM 《Radiology》1993,189(3):918
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Infection with the human immunodeficiency virus type 1 (HIV-1) results in decreased cell-mediated immunity, which includes decreased delayed hypersensitivity to skin test antigens. HIV-1 seropositivity and skin test reactivity to purified protein derivative (PPD) were determined among 2042 healthy Haitian adults with normal chest radiographs. Among HIV-1-seropositive individuals, 52.3% (146/279) had PPD reactions greater than or equal to 10 mm compared with 67.2% (1184/1763) of the seronegative adults (P less than .001). However, the percentage of HIV-1-seropositive individuals with PPD reactions greater than or equal to 5 mm was similar to the percentage of seronegative adults with PPD reactions greater than or equal to 10 mm (180/279 [64.5%] vs. 1184/1763 [67.2%]). Assuming that the rate of prior infection with Mycobacterium tuberculosis was similar for HIV-1-seronegative and -seropositive populations, these data provide support for the recent recommendations to use induration of greater than or equal to 5 mm as evidence of past infection with M. tuberculosis in HIV-1 seropositive adults.  相似文献   
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