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Journal of Autism and Developmental Disorders - Siblings describe positive and negative aspects of autism and often assume lifelong support roles. Less is known about cultural influences on sibling...  相似文献   
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This study tested the proposal that negative appraisals represent a risk factor for developing posttraumatic stress disorder (PTSD) after trauma. Trainee firefighters (N = 68) were assessed during training (before trauma exposure) for PTSD, history of traumatic events, and tendency to engage in negative appraisals. Firefighters were reassessed 4 years later (N = 52), after commencing firefighter duty (after trauma exposure), for PTSD and depression using the Posttraumatic Stress Disorder Scale (E. B. Foa, L. Cashman, L. Jaycox, & K. Perry, 1997) and the Beck Depression Inventory (Version 2; A. T. Beck, R. A. Steer, & G. K. Brown, 1996). At follow-up, 12% met criteria for PTSD. Pretrauma negative appraisals about oneself accounted for 20% of variance in PTSD severity at follow-up. These data provide the first evidence that preexisting negative appraisals are a risk factor for PTSD.  相似文献   
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The synthetic peptides DP-107 and DP-178 (T-20), derived from separate domains within the human immunodeficiency virus type 1 (HIV-1) transmembrane (TM) protein, gp4l, are stable and potent inhibitors of HIV-1 infection and fusion. Using a computer searching strategy (computerized antiviral searching technology, C.A.S.T.) based on the predicted secondary structure of DP-107 and DP-178 (T-20), we have identified conserved heptad repeat domains analogous to the DP-107 and DP-178 regions of HIV-1 gp41 within the glycoproteins of other fusogenic viruses. Here we report on antiviral peptides derived from three representative paramyxoviruses, respiratory syncytial virus (RSV), human parainfluenza virus type 3 (HPIV-3), and measles virus (MV). We screened crude preparations of synthetic 35-residue peptides, scanning the DP-178-like domains, in antiviral assays. Peptide preparations demonstrating antiviral activity were purified and tested for their ability to block syncytium formation. Representative DP-178-like peptides from each paramyxovirus blocked homologous virus-mediated syncytium formation and exhibited EC50 values in the range 0.015-0.250 microM. Moreover, these peptides were highly selective for the virus of origin. Identification of biologically active peptides derived from domains within paramyxovirus F1 proteins analogous to the DP-178 domain of HIV-1 gp4l is compelling evidence for equivalent structural and functional features between retroviral and paramyxoviral fusion proteins. These antiviral peptides provide a novel approach to the development of targeted therapies for paramyxovirus infections.  相似文献   
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Asians and Pacific Islanders (API) are among the fastest growing minority groups within the USA, and this growth has been accompanied by an increase in HIV incidence. Between 2000 and 2010, the API HIV infection rate increased from 4.5% to 8.7%; however, there is a paucity of HIV-related research for this group, and even less is known about the prevalence and correlates of antiretroviral therapy adherence behavior, quality of life, impact of stress, and efficacious self-management among HIV+ API Americans. This paper examines how acculturation and perceived stress affect depression symptomatology and treatment seeking in the HIV+ API population. A series of cross-sectional audio computer-assisted self-interviews were conducted with a convenience sample of 50 HIV+ API (29 in San Francisco and 21 in New York City). The relationship between acculturation and perceived stress was analyzed, and the results indicate that for those HIV+ API who reported low or moderate acculturation (as compared to those who reported high acculturation), stress was significantly mediated by depression symptomology. Interventions to address acculturation and reduce perceived stress among API generally and Asians specifically are therefore needed.  相似文献   
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Thirty depressed patients were compared with 39 controls for their plasma norepinephrine (NE) levels in relation to a cold challenge (placing a hand in ice cold water for 1 minute). Depressed patients showed significantly higher plasma NE levels than controls. Unipolar, but not bipolar patients, had significantly higher plasma NE levels than age- and sex-matched controls. Unipolar melancholic patients who were nonsuppressors on the dexamethasone suppression test showed a strong trend to have higher plasma NE levels than suppressors. These results are further evidence that the NE system is dysregulated in depression.  相似文献   
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目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。 方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。 结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。 结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。  相似文献   
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