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101.
C. R. Ja��n S. Chadha L. M. Tumiel R. O'Shea M. A. Deibel-Braun L. E. Zayas D. Pollock 《Journal of the National Medical Association》1998,90(2):93-98
This study was undertaken to explore the prevalence of perceived dysphoria in a poor, urban, predominantly Puerto Rican community. A cross-sectional sample of 704 adult respondents were asked a single validated question, with a five-item Likert scale response, about their level of perceived dysphoria. Chi-squared analysis and Spearman''s correlation coefficients were used to assess the association of level of dysphoria with social characteristics, barriers to health care, health status, and substance use. Linear regression modeling was used to control for confounding variables. Twenty percent of the respondents were dysphoric. Respondents with no health insurance or no source of health care were least likely to be dysphoric. Persons who perceived distance to the hospital and the doctor, and understanding language of the doctor and office staff as barriers to care were more likely to be dysphoric. Ethnicity was not correlated with level of perceived dysphoria; however, age, gender, and health status were found to be associated with level of dysphoria after controlling for other correlated variables. These results indicate that the psychological needs of communities need to be understood and interventions that are appropriate for the population need to be devised. 相似文献
102.
Saima Hilal Siwei Liu Tien Yin Wong Henri Vrooman Ching-Yu Cheng Narayanaswamy Venketasubramanian Christopher LH Chen Juan Helen Zhou 《Journal of cerebral blood flow and metabolism》2021,41(8):1858
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. 相似文献
103.
LY Zhang S Jejeebhoy IH Shah LH Zhang J Hsia W Im-em 《The European journal of contraception & reproductive health care》2013,18(3):147-154
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. 相似文献
104.
石南藤、山蒟活性成分的分离和结构鉴定 总被引:4,自引:0,他引:4
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。 相似文献
105.
争光霉素A6和它在争光霉素复合物的地位 总被引:8,自引:0,他引:8
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。 相似文献
106.
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 总被引:7,自引:0,他引:7
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,T1/2α仅为2.5min左右,T1/2β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,T1/2β约为140min。 相似文献
107.
大丁草中抗菌活性成分的研究Ⅳ 总被引:1,自引:0,他引:1
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)。 相似文献
108.
胃复安引起过敏性荨麻疹1例 总被引:1,自引:0,他引:1
1 病例报告 男 ,2 4岁 ,因晨起饮冷开水后 ,阵发性上腹痛伴恶心 1h,呕吐 1次来就诊 ,其间无腹泻 .既往无眩晕及肝肾疾病史 .查体 :T36 .8℃ ,HR79次· min- 1 ,BP14.1/10 .2 k Pa,一般状况可 ,咽、扁桃体不充血 ,心肺未见异常 ,腹部平坦 ,未见明显肠型及蠕波 ,左上腹深压痛 ,无肌卫及反跳收稿日期 :2 0 0 0 -0 7-2 1; 修回日期 :2 0 0 0 -0 8-2 3作者简介 :丁向清 (196 8-) ,男 (汉族 ) ,湖北省应城市人 .主治医师 .Tel.(0 431) 79710 16 Ext. 6 6 5 12痛 ,肝脾未及 ,肠鸣音略亢进无气过水声 ,肾区无叩痛 ,胸腹透未见异常 ,WBC 5 .3… 相似文献
109.
F Dorticós R Zayas M Dorantes J Castro C Nieto 《Archivos del Instituto de Cardiología de México》1992,62(2):151-155
Between April 1990 and July 1991, 10 patients, were fulgurated after right atrial endocardial mapping with the purpose of destroying or modifying the site of origin of atrial flutter. Mean age, 47 years old (23-61), 9 males. All patients suffered "common" atrial flutter episodes with very rapid ventricular response (greater than or equal to 150 beats per minute) refractory to pharmacological therapy. All patients had pathologic potentials with prolonged duration between 90 and 160 ms (m = 109) which preceded other reference electrodes in the high right atrium and His position. Electrical stimulation from that zone provoked the capture entrainment and termination of the flutter; the same configuration of the arrhythmia was obtained with electrical stimulation from the suspected zone. With the catheter in that situation one or two direct current cathodic, unipolar shocks were given with energy of 60-150 Joules (m = 117). In the follow up (16-73 weeks), 8 patients are free of symptoms without drugs, one suffered a new episode after 7 weeks, His fulguration was performed and a permanent pacemaker implanted. The other patient has failed two session and is still on treatment. 相似文献
110.
The principal objective of this paper is to provide health practitioners with information on the positive aspects of shorter stature for use in counseling short children with poor self-images. Another objective is to provide information on the physical capabilities, health potential and psychosocial characteristics of shorter stature as a baseline for deciding whether a healthy short child should receive growth hormone therapy. The information presented here was obtained from review of publications covering medical and nutritional research, gerontological studies, athletic performance and environmental, biological and engineering aspects of the human body. It was found that the popular belief in the superiority of tall stature is based primarily on social bias rather than on a scientific foundation. Studies indicating that taller people are healthier or more productive than shorter ones have ignored a wide range of evidence that shorter people are highly creative, productive, long-lived, athletic and better for the environment. The authors urge medical and scientific professionals to consider the many advantages of shorter stature in terms of health, social and environmental benefits. 相似文献