杜仲新炮制工艺参数优选

目的;采用正交试验法对盐杜仲的炮制工艺进行优选试验。方法;选择微波强度和加热时间2个因素,每个因素各取3个水平,按L9（3）4正文表安排试验,用2个指标评定工艺的优劣。结果：采用微波高火,加热15min为最佳工艺条件。结论：微波加热炮制盐杜仲的工艺是可行的。     

瑞典老年高血压试验(STOP-Hypertension)

标　　题　瑞典老年高血压试验中的发病率及病死率作　　者　ＤａｈｌｏｆＢ,ＬｉｎｄｈｏｌｍＬＨ,ＨａｎｓｓｏｎＬ,ｅｔａｌ.　　参考文献　Ｌａｎｃｅｔ,1991,338:1281～1285研究的疾病　高血压病。目　　的　是为了评估抗高血压药物治疗对70～84岁老年高血压患者的益处岁的高血压患者,基础血压≥180/90ｍｍＨｇ,或舒张压≥105ｍｍＨｇ。进入试验前12个月内有心肌梗死、脑卒中、体位性低血压及血压>230/120ｍｍＨｇ者已除外。随　　访　随访1～4年,平均25个月。治疗方案　患者被随机安排接受药物或安慰剂治疗,药物治疗任选下列四种方案…     

树突状细胞与肝脏疾病

免疫反应的产生首先是由抗原提呈细胞(antigenpresenting cells,APC)捕获抗原,经其加工处理后将抗原信息传递给T,B淋巴细胞,从而引发一系列的特异性免疫应答.APC包括树突状细胞(dendritic cells,DC)、巨噬细胞(MΦ)、B细胞等,其中DC是人体内最具潜能的抗原提呈细胞(APC),能在体内外直接激活纯真(naive)T细胞,提呈抗原给MHC-Ⅰ类限制性CD8+和MHC-Ⅱ类限制性CD4+T淋巴细胞,诱导特异性免疫应答[1-6].     

Regeneration of dendritic cells in aged mice

Age-related thymic involution causes a decreased output of thymocytes from the thymus, thereby resulting in impairment of T cell-mediated immunity. While alterations in the T cell and non-haematopoietic stromal compartments have been described, the effects of thymic involution on thymic dendritic cells (DC) are not clearly known. Thymic DC play an essential role in shaping T cell-mediated immune responses by deleting self-reactive thymocytes to establish central tolerance and by inducing regulatory T-cell (Treg) development. It is therefore important to assess the prevalence of and alterations to thymic DC with age, as this may impact on their function. We assessed the numbers and proportions of the three distinct subsets of thymic DC in ageing mice, and showed that these subsets are differentially regulated. This is expected as thymic DC subsets have different origins of development. We further assessed the responses of thymic DC in a regenerative environment, such as that induced by sex-steroid ablation (SSA), and clearly showed that, consistent with global thymus regrowth, all three DC populations increased in numbers and regained their relative proportions to thymocytes after an initial lag period. These findings are important for the clinical translation of thymic regenerative approaches, and indicate that SSA facilitates the maintenance of critical processes such as negative selection and Treg induction through promoting thymic DC regeneration.     

Access to contraceptive services among unmarried young people in the north-east of China

Objective The concerns about the potential threats of human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS) have increased, since, in China, there is a lack of sexual education and condom use is rare. A community-based survey was conducted in September 2001 in Changchun city among 1227 unmarried young people aged 15-24 years (619 males and 608 females) to assess risky sexual practices and the obstacles to accessing appropriate contraceptive and other services. Method The study comprised a survey employing self-administered questionnaires, as well as key informant interviews, focus group discussions and in-depth interviews. This paper investigates the factors associated with young people's access to contraceptive services. Results Results showed that 16% of young people had experienced premarital sexual intercourse and, among them, only 48.2% used contraceptive methods during the first sexual intercourse; 29.9% used a condom. Drug stores were the main source of contraceptives. Conclusions While data are sparse, findings suggest that the hostile and judgmental attitudes of providers, as well as the lack of counseling and privacy, were the key obstacles that unmarried youth encountered in their search for contraceptive services. Findings suggest the need for a reorientation of the contraceptive services to focus on unmarried youth, and generally to make contraceptive services more accessible to young people.     

White matter network damage mediates association between cerebrovascular disease and cognition

To determine whether white matter network disruption mediates the association between MRI markers of cerebrovascular disease (CeVD) and cognitive impairment. Participants (n = 253, aged ≥60 years) from the Epidemiology of Dementia in Singapore study underwent neuropsychological assessments and MRI. CeVD markers were defined as lacunes, white matter hyperintensities (WMH), microbleeds, cortical microinfarcts, cortical infarcts and intracranial stenosis (ICS). White matter microstructure damage was measured as fractional anisotropy and mean diffusivity by tract based spatial statistics from diffusion tensor imaging. Cognitive function was summarized as domain-specific Z-scores.Lacunar counts, WMH volume and ICS were associated with worse performance in executive function, attention, language, verbal and visual memory. These three CeVD markers were also associated with white matter microstructural damage in the projection, commissural, association, and limbic fibers. Path analyses showed that lacunar counts, higher WMH volume and ICS were associated with executive and verbal memory impairment via white matter disruption in commissural fibers whereas impairment in the attention, visual memory and language were mediated through projection fibers.Our study shows that the abnormalities in white matter connectivity may underlie the relationship between CeVD and cognition. Further longitudinal studies are needed to understand the cause-effect relationship between CeVD, white matter damage and cognition.