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.     

溃结Ⅰ号的制备与稳定性考察

目的提高医院临时处方溃结Ⅰ号保留灌肠剂的稳定性,并对其中的主要成分含量进行控制。方法制备时加入助悬剂,用沉降容积比和再分散性选择适宜的助悬剂及其最佳助悬浓度,并用紫外分光光度法对主要成分柳氮磺吡啶的含量进行测定。结果在制剂中加入卡波母作为助悬剂0.15%就可以达到良好的助悬效果,而且制备的制剂再分散性好。结论加入卡波母作为助悬剂制备的制剂稳定,再分散性好,便于使用和保存。     

石南藤、山蒟活性成分的分离和结构鉴定

已报道自山蒟及石南藤中分得海风藤酮(Ⅰ),denudatin B(Ⅱ),N-isobutyl-deca-trans-2-trans-4-dienamide(Ⅲ),本文继续报道自山蒟中分得一新木脂素,命名为山蒟素D(Ⅳ),X-衍射晶体结构测定为外消旋光学异构体。自石南藤分得Ⅳ的同系物,为新结构、命名为南藤素(Ⅴ),以及山蒟素C(Ⅵ),galgravin(Ⅶ),二氢毕拨明宁碱(Ⅷ)及巴豆环氧素(Ⅸ)。以上化合物皆首次自山蒟及石南藤中分得。以血小板活化因子(PAF)引起的血小板凝集实验测定活性,除Ⅲ,Ⅳ,Ⅶ,Ⅸ外皆有抑制活性。     

争光霉素A6和它在争光霉素复合物的地位

争光霉素A₅已鉴别为Bleomycin A₆,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A₆在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A₆例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A₆,而Bleomycin A₆仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。     

高效液相色谱法测定血浆中醋氯芬酸及其在犬体内药代动力学

建立了HPLC法同时测定家犬血浆中的醋氯芬酸及其主要代谢物的浓度。此法简便易行,精密度好,方法回收率91.3%～96.9%,日内、日间RSD为3.69%～8.13%,血药浓度在0.050～51.2μg·mL^-1范围内呈线性关系,相关系数0.9998,当S/N≥3时,最小检测浓度为10ng·mL^-1。此法可同时测定醋氯芬酸及其在体内的主要代谢物。醋氯芬酸po吸收迅速,给药后约12min即达血药浓度峰值,其药—时曲线符合二室模型,T_1/2α仅为2.5min左右,T_1/2β约为137min,代谢物约在110min达到血药浓度峰值,峰浓度为3.20μg·mL^-1,T_1/2β约为140min。     

大丁草中抗菌活性成分的研究Ⅳ

从秋季采收的菊科植物大丁草Gerbera anandria(L.)Sch Bip.全草中共分出十三种成分。本文报道其中三个新化合物的结构鉴定.它们分别是3,8-dihydroxy-4-methoxy-coumarin(ⅪⅩ),3,8-dihydroxy-4-methoxy-2-oxo-2 H-1-benzopyran-5-carboxylic acid(ⅩⅦ),和5,8-dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3-)-coumarin(ⅩⅪ)。