Structure-acute toxicity relationship of aromatic hydrocarbons in mice

The structure-acute toxicity relationship of aromatic hydrocarbons was examined in mice. In all test compounds, the acute toxicity was determined under 2 conditions: control LD₅₀ (LD₅₀-cont) and carbon tetrachloride (CCl₄)-pretreated LD₅₀ (LD₅₀-CCl₄). The CCl₄-pretreatment was done in order to evaluate the toxic potency of compound itself without the influence of metabolism. Both log (1/LD₅₀-cont) and log (1/LD₅₀-CCl₄) were functions of the log P, n-octanol/water partition coefficient, i.e., log (1/LD₅₀-cont) = 0.080 log P − 1.532 and log (1/LD₅₀-CCl₄) = −0.040(log P)² + 0.157 log P − 1.373. Both equations were statistically significant (P < 0.01). The ratio of LD₅₀-cont/LD₅₀-CCl₄ indicated that metabolic activation is more evident in hydrophobic compounds than in hydrophilic compounds. The results suggest that hydrophobicity of the aromatic hydrocarbons plays an important role in determining their acute toxicity.     

SARS家庭聚集型病例8例报告分析

SARS是由变异冠状病毒引起的新型烈性传染病，具有在家庭和医院内聚集发病的特点。其影像学表现对于临床诊断和随诊观察具有重要价值。本文报告了分属3个家庭的8个病例发病早期(1周)影像学表现(包括胸部平片和CT)和部分临床表现资料，讨论并分析SARS早期影像学表现的若干特点及与临床表现之间的关系。     

Dentists evaluate their patients: An empirical investigation of preferences

Dental treatment is a dyadic encounter. Yet research on the dentist-patient dyad has tended to focus on patient perceptions of dentist, to the neglect of dentist perceptions of patient. Previous theoretic and qualitative work on caregiver perceptions of patients suggested three dimensions of evaluation. Dentists (N=618) rated their patients on items taken from two prior studies. Dentists' responses were subjected to confirmatory factor analysis. The analysis substantiated the existence of three evaluative dimensions: compliance, tractability, and likability. Further analysis showed that the three dimensions formed a Guttman simplex, revealing a second-order factor of selectivity and allowing a classification of dentists on the basis of patient selectivity.This study was funded by a grant from the University of Connecticut Research Foundation.     

Preterm Birth: Implications for Family Stress and Coping

The event of preterm birth represents a significant risk to the equilibrium of the family, often placing the family under significant stress. This paper is intended to assist neonatal nurses in understanding factors related to a family's appraisal of stress and strategies used for coping. Such factors are an important consideration in planning the most effective interventions to support optimal family adaptation to their preterm infant's birth. In identifying the best clinical approaches to supporting a family coping with the event of a preterm birth, nurses need to consider levels of the evidence that supports adoption of clinical intervention strategies. Working to reduce family stress and improve family coping ensures the most optimal home environment for the preterm infant to grow and thrive in after discharge.     

Evaluation of human antibody responses to diphtheria toxin subunits A and B in various age groups

This study aimed to evaluate human antibody responses to diphtheria toxin subunits in various age groups. Antibodies against the intact diphtheria toxin and the diphtheria toxin subunits A and B were evaluated in 1319 individuals using a double-antigen ELISA. Although high levels of protection (83.6%, 95% CI 79.2-87.4) were found in children and adolescents, the middle-aged adult population was less protected (28.8%, 95% CI 24.3-33.6). An increase in age was associated with a decrease in the frequency of protected individuals in the 0-39-year age group (p <0.001). Anti-subunit B levels correlated well (p <0.01) with levels of antibodies against the intact toxin. In children aged < or =16 years, the intervals at which the peaks in geometric mean titres of anti-subunit B antibodies were observed were found to correlate with the ages at which booster doses are administered. Overall, males appeared to be more protected than females (OR 1.67, 95% CI 1.34-2.08, p <0.001). A small group of individuals had antibody levels of > or =0.1 IU/mL against the intact toxin, but did not have protective antibody against subunit B. Determination of anti-subunit B antibody levels should help in evaluating the effectiveness of diphtheria boosters and other aspects of diphtheria immunity.     

药物的定量构效关系的方法学研究——改进的逐步回归算法

在定量的构效关系研究中,多重回归分析选人的参数,多是用穷举所有方程实现的。本文提出一种改进的逐步回归算法,计算实例表明,是个行之有效的方法。     

矿区居民预防艾滋病／性传播疾病同伴教育效果研究

目的　调查对矿区居民开展预防艾滋病 /性传播疾病同伴教育的效果。方法　以自愿报名的方式选取山西省大同市永定庄矿区矿工 2 5名 ,均为男性 ,平均年龄为 3 4 0± 8 3岁 ;矿工家属 2 5名 ,均为女性 ,平均年龄为 46 8± 1 1 7岁。在矿工组和矿工家属组中各随机抽取 1名作为同伴教育者进行培训。培训合格的同伴教育者以不同的形式对其余 2 4名同伴进行 1个小时的教育。于教育前和教育后 1周对每组的 2 4名同伴就艾滋病/性传播疾病的知、信、行做问卷调查。并于 1周后按单纯随机抽样方法在每组选取 8人分别进行访谈。结果　在同伴教育者中 ,关于艾滋病 /性传播疾病的一般知识答对率培训前为 2 6 4% ,培训后为 77 6% ;关于传播途径 ,培训前为 2 3 2 % ,培训后为 90 8% ;关于相关的预防措施 ,培训前为 3 5 4% ,培训后为 74 9%。所有的同伴教育者认为艾滋病 /性传播疾病健康教育是必要的 ,同伴教育是一种有效的方式。结论　在矿工及其家属中开展艾滋病 /性传播疾病同伴教育是有效的     

神经症与精神分裂症患者家庭环境的对照研究

目的：探讨神经症患者家庭环境的特点。方法：采用家庭环境量表中文版，对50例神经症患者进行调查 ，并按1：1配对原则分别与50例精神分裂症，50例正常对照组进行比较。结果：（1）与正常对照组相比神经症患者的家庭关系表现为低亲密度、高矛盾性及道德宗教观的差异；（2）与精神分裂症相比仅表现为控制性差，而两对照组之间表现为精神分裂症患者家庭低亲密度、高矛盾性、文化娱乐性缺乏和道德宗教观的不同。结论：不良的家庭环境，对子女患精神疾病有重要影响，但它们之间没有明显特异性。     

犯罪青少年个性与父母养育方式的相关研究

目的 分析和探讨犯罪青少年个性和父母养育方式的特点及父母养育方式对犯罪青少年个性特质的影响。方法 以河南省某少年管教所少年犯240人为研究组，以240名在校中学生240名为对照组，采用艾森克个性问卷(EPQ)和父母养育方式问卷(EMBU)对两组被试进行集体施测。结果 犯罪青少年个性具有N(情绪性)分和P(精神质)分高、E(内外向)分低的特点；其父母养育方式表现出低情感温暖、理解，高惩罚严厉、高拒绝否认和过分偏爱的特点。犯罪青少年个性4个维度与其父母养育方式的绝大多数因子存在显相关关系。结论 犯罪青少年人格具有偏离正常的倾向，其父母养育方式失当可能是造成犯罪青少年人格偏差的重要因素。     

Synthesis and cytotoxic activity of new alkyl[3-(2-chloroethyl)ureido]benzene derivatives

Several alkyl[3-(2-chloroethyl)ureido] (CEU) benzene derivatives were prepared as potential anticancer agents. These new compounds were readily prepared in good yields by addition of anilines to 2-chloroethylisocyanate. Their cytotoxic activity was evaluated on human breast cancer (MDA-MB-231), human colon adenocarcinoma (LoVo) and mouse lymphocytic leukemia (P388D₁) tumor cell lines. Several new CEUs were significantly more cytotoxic than the nitrogen mustard chlorambucil. The biological activity of these aromatic urea derivatives seems to be related to the nature and position of the alkyl substituents on the aromatic ring. Substitution by branched alkyl groups on position 4 of the aromatic ring led to cytotoxic molecules which are up to 5 times more potent than the standard chlorambucil.