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881.
BACKGROUND: Changes in hepatitis C virus (HCV) genotype distribution with time have been reported in several countries. GOALS: To explore eventual changes in HCV genotype distribution in Venezuela over a 10 years period. STUDY: HCV genotype was determined by direct sequencing of the 5' noncoding region, in 236 isolates circulating in patients treated during years 2005 to 2006. Genotype distribution was compared with the one observed in 43 patients followed during years 1994 to 1996. RESULTS: The prevalence HCV genotype 1 and 2 was 70% and 26%, respectively, in patients followed during years 1994 to 1996. The frequency of genotype 2 was significantly increased to 41% (P=0.04) in patients treated during years 2005 to 2006. A significant reduction in HCV genotype 1b prevalence (48% to 27%, P=0.01) was also observed after this 10 years period, whereas the prevalence of HCV genotype 1a did not change over time (22% vs. 27%, NS). Transfusion was more significantly associated with infection with HCV genotype 1b than with other genotypes (52% vs. 20%, P=0.002). CONCLUSIONS: HCV subtype 1b seems to have been displaced by HCV genotype 2 in a relatively short period, without increase in the frequency of genotype 3. The low frequency of HCV genotype 3 in Venezuela might be due to the fact that intravenous drug use in Venezuela is less common than in other countries. The implementation of anti-HCV testing in blood banks since 1994 in Venezuela, might have contributed to the reduction in the frequency HCV genotype 1b infection.  相似文献   
882.
Bisexual behaviors may increase transmission pathways of HIV and sexually transmitted infections (STIs) from a higher prevalence group to lower prevalence groups in El Salvador. In 2008, men who have sex with men (MSM) were recruited in San Salvador and San Miguel using respondent driven sampling. Participants were interviewed and tested for HIV and STIs. Sixteen seeds and 797 MSM participated; 34.9% in San Salvador and 58.8% in San Miguel reported bisexual behavior. Bisexual behavior was associated with drug use (adjusted odds ratio (AOR) = 2.57, 95% CI: 1.30–5.06) and insertive anal sex (AOR = 5.45, 95% CI: 3.01–9.87), and inversely associated with having a stable male partner (AOR = 0.47, 95% CI: 0.26–0.84) and disclosing MSM behavior to family (AOR = 0.41, 95% CI: 0.22–0.75). Bisexual behavior was associated with risk behaviors with male and female partners that may be associated with HIV and STI transmission. Bisexual men displayed a distinct identity calling for tailored interventions.  相似文献   
883.
This article explores the relationships between certain cognitive and emotional factors (sensation seeking, impulsivity, self-esteem, anxiety sensitivity and loneliness) and regular consumption of alcohol and other drugs by a university population from Almería (South Spain). During 2005 and 2006 students were given a battery of questionnaires related to these personality variables and the substances they had consumed. After filling out the psychometric tests, the participants gave a urine sample which was then analyzed. The findings stress the role of sensation seeking and loneliness, understood as social maladjustment, in the regular consumption of alcohol and other drugs, in both men and women.  相似文献   
884.
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