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BACKGROUND: Volunteer black adolescent females from neighborhoods characterized by high rates of unemployment, substance abuse, violence, and sexually transmitted disease were studied to determine the frequency of condom use and unprotected vaginal sex with steady, older partners during various time periods over the previous 6 months. GOAL: To examine associations between having male sex partners who were typically older (by at least 2 years) and adolescent females' sexually transmitted disease (STD)/HIV-associated sexual risk behaviors. STUDY DESIGN: In this cross-sectional study, 522 sexually active black adolescent females completed a questionnaire and a structured interview, of which a portion assessed the age difference between the adolescents and their typical sex partners. The adolescents' ages, length of relationship and their use of hormonal contraception were identified as covariates. Adjusted odds ratios (AOR), their 95% confidence intervals, and respective P values were calculated to detect significant associations. RESULTS: Sixty-two percent of the adolescents reported their typical sex partners were at least 2 years older. These adolescents were more likely to report never using condoms during the most recent sexual encounter (AOR = 2.0), during the last five sexual encounters (AOR = 2.0), and during the past month (AOR = 2.2). Similarly, having older partners was associated with greater odds of reporting any unprotected vaginal sex in the past 30 days (AOR = 1.7) or the past 6 months (AOR = 1.5). CONCLUSION: Our findings suggest that many adolescent females have sex partners who are at least 2 years older and that their relationship dynamics do not favor the adoption and maintenance of behavior protective against STD or HIV infection. Prevention programs could include training designed to help adolescent females overcome barriers to safer sex with older male partners.  相似文献   
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背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。  相似文献   
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OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
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Summary. This paper describes studies on the source, preparation, characterization and storage of human ferritin for use as a standard for the immunoassay of serum ferritin. Ferritin was prepared from the liver or spleen by methods including either ultracentrifugation or cadmium sulphate crystallization. Preparations were characterized by polyacrylamide gel electrophoresis in dissociating and non-dissociating buffers, iso-electric focusing, analysis of amino acid composition and measurement of protein content. The protein content of solutions of liver or spleen ferritin may be determined by the method of Lowry with bovine serum albumin as standard. Lyophilization under carefully controlled conditions in buffer containing high concentrations of albumin provides a stable preparation of ferritin. Accelerated degradation and collaborative immunological studies of two lyophilized preparations of ferritin, one from liver and one from spleen, indicate that either is an acceptable reference material.  相似文献   
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ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics.  相似文献   
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The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae.  相似文献   
40.
Psychiatric disorders are not uncommon among severely obese patients who present for bariatric surgery. This paper (1) reviews the results of the published studies using the structured interviews to assess psychopathology in bariatric surgery candidates; (2) compares the prevalence rates of psychiatric disorders across these studies with the data from other population samples; and (3) assesses whether sociodemographic variables appear to affect these prevalence rates. We searched online resources, PubMed, PsychINFO and reference lists of all the relevant articles to provide an overview of evidence so far and highlight some details in the assessment and comparisons of different samples in different countries. The prevalence estimates in the non-treatment obese group did not appear to differ substantially from the general population group in the US or the Italian population samples, although they were relatively higher for the German population. However, the rates of psychopathology in the bariatric surgery candidates were considerably higher than the other two population groups in all the samples. Overall, the most common category of lifetime Axis I disorders in all the studies was affective disorders, with anxiety disorders being the most common category of current Axis I disorders. Certain demographic characteristics are also associated with higher rates of psychopathology, such as, female gender, low socioeconomic status, higher BMI. Overall, methodological and sociodemographic differences make these studies difficult to compare and these differences should be taken into account when interpreting the results.  相似文献   
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