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BACKGROUND: A low level of response to alcohol has been associated with both the genetic constitution of the regulatory region (SLC6A4) of the human serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) and with future alcohol intake and an increased risk for alcoholism. To date, all studies of relevant polymorphisms have been carried out in populations in the United States. METHODS: Data were extracted from a subset (n = 243) of a cohort of children who have been observed since birth through evaluation of the family history of alcoholism and psychosocial risk influences. At age 16 years, the response to alcohol was assessed with the Self-Rating of the Effects of Alcohol (SRE) questionnaire, and the average amount of alcohol intake per month was assessed during the prior 6 months. Additional variables that were measured included the 5-HTT genotype, externalizing behavior, and sociodemographic variables, such as gender and age. RESULTS: The level of response to alcohol was significantly lower among carriers of two long alleles of the 5-HTT regulatory region compared with carriers of one or two short alleles (Mann-Whitney U = 5225.0, p = .005). In a multiple regression analysis, the level of response to alcohol and externalizing behavior but not psychosocial factors significantly predicted the average amount of alcohol intake per month. CONCLUSIONS: This study demonstrates that, independent of the assessed psychosocial variables, the 5-HTT genotype correlated with the level of response to alcohol and predicted alcohol intake among 16-year-old adolescents.  相似文献   
3.
The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested.  相似文献   
4.
静脉输液药物集中配置、管理是我国医院管理的一项新举措.长期以来,临床静脉输液中的加药工作一直是由护士在治疗室独立完成,这种方式存在着很多不足之处.在这种环境污染下,职业健康安全管理越来越受到各国政府的重视.为了提高服务质量,预防和控制可能存在的环境污染及职业健康安全风险,国家颁布 GB/T24001~ 1996<环境管理体系规范和使用指南>, GB/T28001-2001<职业健康安全管理体系规范>标准,引进国外的先进管理模式,此项工作由药师和护士共同完成,以期达到合理用药减少药物的流失和浪费,科学配置、降低输液反应.静脉药物配置中心把静脉药物配置从普通环境的治疗室转为在具有洁净条件的配置中心进行集中管理配置,保证配置出来的药品安全无菌、有效.需要输液的患者在舒适、整洁和安静的环境下进行输液,减少临床护理工作量的目的,把更多的时间还给病人.这为顺利实施静脉配置中心的项目提供了保障,确保了输液中心正常运行.  相似文献   
5.
As part of the strategy for the design of macromolecular carriers for drug targeting, the disposition characteristics of macromolecules were studied in mice bearing tumors that served as target tissues. Eight kinds of macromolecules including four polysaccharides and four proteins with different molecular weights and electric charges were used; tissue distribution and tumor localization after intravenous injection were studied. Pharmacokinetic analysis revealed that the tissue radioactivity uptake rate index calculated in terms of clearance was different among the tested compounds; especially, the urinary radioactivity excretion clearances and the total hepatic radioactivity uptake clearances varied widely. Compounds with low molecular weights (approximately 10 kD) or positive charges showed lower tumor radioactivity accumulation; radioactivity was rapidly eliminated from the plasma via rapid urinary excretion or extensive hepatic uptake, respectively. On the other hand, large and negatively charged compounds, carboxymethyl dextran, bovine serum albumin, and mouse immunoglobulin G, showed higher radioactivity accumulation in the tumor (calculated total amounts were 15.6, 10.8, and 20.8% of the dose, respectively) and prolonged retention in the circulation. These results demonstrated that the total systemic exposure rather than the uptake rate index was correlated with total tumor uptake. Molecular weight and electric charge of the macromolecules significantly affected their disposition characteristics and, consequently, determined radioactivity accumulation in the tumor. It was concluded that a drug–carrier complex designed for systemic tumor targeting should be polyanionic in nature and larger than 70,000 in molecular weight.  相似文献   
6.
Summary In the present study the effect of metastatic liver disease on hepatic drug metabolism has been examined by studying the pharmacokinetics of antipyrine and the urinary excretion of antipyrine and its three major metabolites (4-hydroxyantipyrine, norantipyrine, and 3-hydroxymethylantipyrine) in 12 patients with extensive metastatic liver disease, and in 12 matched healthy controls.In the patients total liver volume, the volume of the liver parenchyma, and the volume of the liver metastases were determined by computed tomography. The volume of liver metastases always exceeded 35% of the total liver volume.There were no significant differences between the patients and controls in plasma half-life, plasma clearance, or apparent volume of distribution of antipyrine.The cumulative urinary excretion of antipyrine and its three major metabolites was significantly lower in patients [44 (18)%] than in controls [71 (8)%]. The excretion of antipyrine itself was unchanged and the decrease in cumulative excretion was due to reduced excretion of the three metabolites.The results show that the activity of the hepatic mixed function oxidases was not impaired even in patients with extensive metastatic liver disease. This may be because liver metastases do not cause a corresponding reduction in the volume of normal hepatic parenchyma. The decreased urinary excretion of the three major metabolites of antipyrine, which are mainly glucuronidated, may have been due to an alteration in the process of conjugation.  相似文献   
7.
手术室是医学技术与工程技术结合的产物。随着医疗技术和新的手术工具的不断涌现,带动了手术量的迅猛上升。旧的手术室空间布局、实施标准、功能配置等方面已经无法满足新技术的应用要求,同时人们对手术环境和手术质量也提出了更高的标准。而今第四代手术室已开始步入我们的时代。洁净化、数字化和人性化则是其主要代表特征。本文分别从洁净手术室、数字化手术室和人性化手术室三个方面来探讨现代医院手术室建设中应注意的问题及动态研究。层流手术室已经是手术室建设不可逆转的发展趋势,除了按照《医院洁净手术部建筑技术规范》来建造外,其布局、人流、物流、质量监控等等都要进行合理的安排才能达到最优的手术环境。数字化手术室是将温度、湿度、压力、通风量、新风量等一切参数系统的由计算机来分配统筹,从而实现精确高效的手术管理。人性化手术室则是手术室建设的软件部分,是一种“以病人为中心”的服务理念,它打破了传统的生物医学模式,转变为生物—心理—社会模式,这是病人需求与市场竞争的必然选择。  相似文献   
8.
大学生时间管理倾向与自我和谐的关系   总被引:1,自引:0,他引:1  
目的: 探讨大学生时间管理倾向与自我和谐的关系.方法: 运用青少年时间管理倾向量表和自我和谐量表对334名大学生进行施测,对大学生时间管理倾向与自我和谐各因素进行相关分析和多元逐步回归分析.结果: 334名大学生自我与经验的不和谐得分为51.9±8.6,自我灵活性得分24.6±6.3,自我刻板性得分25.0±4.1;自我与经验的不和谐与除时间价值感外的时间管理倾向(r=-0.31--0.39)、自我刻板性与时间管理倾向(r=-0.11--O.26)呈负相关;自我灵活性与时间管理倾向呈正相关(r=0.28-O.41).进一步回归分析表明,时间效能感是自我与经验的不和谐和自我刻板性的有效预测变量(R2=0.152,β=-0.390;R2:O.107,β=-0.259);时间效能感和时间价值感是自我灵活性的有效预测变量(R2=0.229,β:0.288、0.286).结论: 大学生时间管理倾向与自我和谐有一定程度的相关.  相似文献   
9.
中学生心理控制源和时间管理倾向的相关研究   总被引:10,自引:2,他引:10  
目的:探讨中学生心理控制源与时间管理倾向的关系.方法:采用"青少年时间管理倾向量表"和"内在-外在心理控制源量表"对599名中学生进行调查.结果:初中学生比高中学生更倾向于内控,时间管理明显好于高中学生;中学生心理控制源与时间管理倾向之间存在显著的负相关;高时间管理者和低时间管理者的心理控制源差异显著.结论:中学生的心理控制源与时间管理倾向呈显著的负相关.  相似文献   
10.
The ethical and legal issues arising from genetic screening in embryo donation are discussed in relation to two recent cases where embryos with uncertain genetic health were offered for donation.  相似文献   
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