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41.
BACKGROUND: Heroin users who do not inject constitute a large pool of drug users with a potentially important impact on public health. We aimed to estimate the incidence of hepatitis C virus (HCV) among heroin users who had never injected (NIDUS) at baseline, and the effect of starting injecting during follow-up, other percutaneous exposures, sharing snorting paraphernalia, cocaine/crack use, and risky sexual behaviour on HCV-seroconversion. METHODS: Prospective cohort of 305 HCV-negative NIDUs at baseline, aged 18-30 and street-recruited in three Spanish cities in 2001-2003. Computer-assisted personal interviews were conducted and dried blood-spot samples were collected. Bivariate and multivariable Poisson models were used. RESULTS: Among the 305 never-injectors who were HCV-negative at baseline, 197 (64.6%) were followed-up and 21 seroconverted [HCV-incidence rate=5.8/100 person-years at risk (pyar) (95% CI: 3.6-8.9)]. HCV incidence in new-injectors was 28.4/100pyar [(95% CI, 14.7-49.7) vs. 2.8/100pyar (95% CI, 1.3-5.4)] among NIDUs. Of the risk exposures considered, starting injecting was the only predictor of HCV-seroconversion [adjusted relative risk=10.1, 95% CI: 3.8-26.7]. CONCLUSION: The HCV-seroconversion rate was 10 times higher among new-injectors than never-injectors. No predictors other than starting injecting were found for HCV-seroconversion. Harm reduction interventions to prevent HCV infection should include prevention of drug injection.  相似文献   
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Community-based support group participation protects against substance use disorder (SUD) relapse, but referrals during treatment are inconsistently delivered and may not acknowledge barriers facing rural patients. This formative evaluation of a rural intensive referral intervention (RAIR) to community-based support groups for Veterans seeking SUD treatment surveyed patients (n = 145) and surveyed and interviewed treatment staff (n = 28). Patients and staff did not differ significantly on quantitative ratings of the helpfulness of, or satisfaction with, seven RAIR components, but staff did not deliver the intervention consistently or as designed, citing two themes: lack of commitment and lack of resources.  相似文献   
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Frontoparietal connections underlie key executive cognitive functions. Abnormalities in the frontoparietal network have been observed in chronic alcoholics and associated with alcohol-related cognitive deficits. It remains unclear whether neurobiological differences in frontoparietal circuitry exist in substance-naïve youth who are at-risk for alcohol use disorders. This study used functional connectivity magnetic resonance imaging and diffusion tensor imaging to examine frontoparietal connectivity and underlying white matter microstructure in 20 substance-naïve youth with a family history of alcohol dependence and 20 well-matched controls without familial substance use disorders. Youth with a family history of alcohol dependence showed significantly less functional connectivity between posterior parietal and dorsolateral prefrontal seed regions (ps < .05), as compared to family history negative controls; however, they did not show differences in white matter architecture within tracts subserving frontoparietal circuitry (ps > .34). Substance-naïve youth with a family history of alcohol dependence show less frontoparietal functional connectivity in the absence of white matter microstructural abnormalities as compared to youth with no familial risk. This may suggest a potential neurobiological marker for the development of substance use disorders.  相似文献   
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Uterine leiomyomas are the most common pelvic tumors in women. These neoplasms are usually found in the uterus and their development in other locations, such as the vagina, is unusual. We report the case of a 42-year-old woman who presented with a 2-year history of a tumor in the left vulvovaginal area with no other symptomatology. On examination, a tumor of approximately 4 cm could be palpated inside the left labia majora. The tumor extended to the ischiorectal fossa with an impression in the rectum but without infiltration. Pelvic magnetic resonance imaging showed a solid-cystic vulvar and/or vaginal tumor of likely neoplastic origin which did not involve the pelvic diaphragm and which reached the perineal area. Tumoral enucleation was performed through the vaginal route, with no complications. Pathological study confirmed a benign leiomyoma. A review of the topic is provided.  相似文献   
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