铰链式冠外附着体的结构强度分析

目的探讨铰链式冠外附着体设计的合理性.方法采用有限元应力分析的实验方法,分析铰链式冠外附着体阳性结构L形球体的应力分布情况,对其结构强度进行测试.结果在附着体阳性结构L形球体的转角处应力最大,应力值为321.847MPa.结论该铰链式附着体的结构强度符合临床设计要求.     

LSECtin interacts with filovirus glycoproteins and the spike protein of SARS coronavirus

Cellular attachment factors like the C-type lectins DC-SIGN and DC-SIGNR (collectively referred to as DC-SIGN/R) can augment viral infection and might promote viral dissemination in and between hosts. The lectin LSECtin is encoded in the same chromosomal locus as DC-SIGN/R and is coexpressed with DC-SIGNR on sinusoidal endothelial cells in liver and lymphnodes. Here, we show that LSECtin enhances infection driven by filovirus glycoproteins (GP) and the S protein of SARS coronavirus, but does not interact with human immunodeficiency virus type-1 and hepatitis C virus envelope proteins. Ligand binding to LSECtin was inhibited by EGTA but not by mannan, suggesting that LSECtin unlike DC-SIGN/R does not recognize high-mannose glycans on viral GPs. Finally, we demonstrate that LSECtin is N-linked glycosylated and that glycosylation is required for cell surface expression. In summary, we identified LSECtin as an attachment factor that in conjunction with DC-SIGNR might concentrate viral pathogens in liver and lymph nodes.     

A simple method for measurement of inulin in nanoliter samples using glass capillaries

Summary A simple method using glass capillaries instead of microcuvettes for measurement of inulin in nanoliter samples is given. Inulin was determined with anthron reagent (5 or 10 nl samples +3 l anthron reagent). Glass capillary tubes (o.d.=1 mm, i.d.=0.68 mm, length=150 mm) in which the chemical reaction took place during incubation at 56°C were directly introduced into the optical system of a Zeiss spectrophotometer PMQ II with sphere attachment and objective.Extinction was measured vertically to the axis of the capillary. The changes of extinction of 20 different capillaries with the blank at different positions was only 1.13×10^–3. The exactness of measurement in the concentration range of 100 200 400 750 1500 3000 mg-% inulin was for 5nl/3 l: 19.8 11.0 6.7 4.7 3.0 2.2%. 10nl/3 l: 13.0 8.4 5.1 3.9%.This method of measurement may also be applicable for other colorimetric reactions with nanoliter samples.This work was supported by Fonds zur Förderung der wissenschaftlichen Forschung.     

Attachment security: a meta-analysis of maternal mental health correlates

This meta-analysis addresses the association between attachment security and each of three maternal mental health correlates. The meta-analysis is based on 35 studies, 39 samples, and 2,064 mother-child pairs. Social-marital support (r = .14; based on 16 studies involving 17 samples and 902 dyads), stress (r = .19; 13 studies, 14 samples, and 768 dyads), and depression (r = .18; 15 studies, 19 samples, and 953 dyads) each proved significantly related to attachment security. All constructs showed substantial variance in effect size. Ecological factors and approach to measuring support may explain the heterogeneity of effect sizes within the social-marital support literature. Effect sizes for stress varied according to the time between assessment of stress and assessment of attachment security. Among studies of depression, clinical samples yielded significantly larger effect sizes than community samples. We discuss these results in terms of measurement issues (specifically, overreliance on self-report inventories) and in terms of the need to study the correlates of change in attachment security, rather than just the correlates of attachment security per se.     

Prevalence of the chemokine receptor CCR5-Delta32 gene mutation in periodontal disease

A 32-base-pair deletion in the CCR5 gene was previously shown to influence the susceptibility for several infectious diseases. The present study compared the frequency of the CCR5-Delta32 mutation among subjects with periodontal disease and healthy control individuals. The prevalence of the CCR5-Delta32 mutation was determined in 81 patients with generalized periodontitis and 121 healthy controls. Standardized clinical and radiographic criteria were used for the diagnosis of periodontitis for each subject. The CCR5-Delta32 mutation was identified by PCR amplification and subsequent agarose gel electrophoresis. Genotype and allele frequencies among both study groups were compared using Fisher's exact test at a level of significance of 5% (P<0.05). The frequency of the CCR5-Delta32 allele was 9.9% (16/162) for periodontitis patients and 10.7% (26/216) for the healthy controls. The allele frequencies between periodontitis patients and the control group for the CCR5-Delta32 mutation were not significantly different (P=0.801). The present study revealed no association between the CCR5-Delta32 mutation and susceptibility to periodontal disease.     

大学生抑郁情绪与成人依恋的关系研究

目的 考察大学生的抑郁情绪与成人依恋的关系.方法 采用流调中心用抑郁量表和成人依恋量表,对河南某高校随机抽取的288名大一至大四的学生进行了调查.结果 ①大学生的抑郁情绪在性别与年级的交互作用上差异显著.②大学生成人依恋的不同类型对其抑郁情绪有影响,其中,拒绝型和恐惧型的大学生在抑郁情绪上有显著差异.结论 成人依恋的类型对大学生的抑郁情绪有显著影响.     

婚恋依恋研究进展

近年来依恋研究已由亲子依恋、依恋表征拓展到婚恋依恋．婚恋依恋是成人与情侣间的依恋情感联结。该文介绍了婚恋依恋提出的背景和主要观点、婚恋依恋类型及测量方法、有关婚恋依恋的主要研究成果、最后探讨了婚恋依恋领域有待深入研究的问题。     

大鼠实验性牙周炎一氧化氮含量改变的研究(英文)

目的：通过建立大鼠牙周炎实验模型，测量牙龈组织中亚硝酸盐(NO2-)和硝酸盐(NO3-)的含量，比较一氧化氮(NO)含量与附着丧失(AL)的关系，探讨NO在牙周炎病理进程中的作用。 方法： 健康Sprague-Dawley大鼠共72只，随机分为两组：正常对照组和牙周炎组，每组36只。参照Di Paola法复制大鼠牙周炎动物模型。分别于术后1、4和8周时处死动物，每个时点每组处死的动物数为12只。采用分光光度仪测量大鼠牙龈组织中亚硝酸盐（NO2-）和硝酸盐(NO3-)的含量，以间接确定NO含量；采用组织切片法观察牙周组织的组织学改变；应用Tiger细胞图像仪测量AL。 结果： 术后4周和8周时，实验性牙周炎组牙龈组织NO2-/NO3-含量明显高于正常对照组(P<0.01)；在牙周炎组，术后8周牙龈组织NO2-/NO3-含量明显高于术后4周(P<0.01)。在牙周炎组，术后4周和8周与术后1周比较，AL显著增加(P<0.01)；术后8周与4周比较，AL显著增加(P<0.01)。 结论： 牙周炎组牙龈组织NO2-/NO3-含量明显高于正常对照组；NO2-/NO3-含量与牙周组织的AL直接相关。结果表明NO在牙周组织的炎症和破坏过程中发挥作用，提示在牙周炎的治疗中控制NO具有临床应用价值。     

Separation distress and attachment in surrogate-reared squirrel monkeys.

Surrogate-reared infant squirrel monkeys were exposed to various conditions of separation from their surrogate. Infants showed significant increases in plasma levels of cortisol when they were placed in an unfamiliar environment during the separation period. Changes in behavior, but not cortisol, were observed under conditions in which the surrogate was removed and the infant left in the home cage. These results differ from those previously obtained with mother-reared infants. It is concluded that surrogate-reared infant squirrel monkeys do not show the same separation response or attachment to their rearing figure as do mother-reared infants.     

Stress, attachment and skin diseases: a case-control study

Objectives In this case-control study we tested the hypothesis of an association between some psychosomatic skin diseases, attachment style and stress. Patients and methods A total of 177 cases and 194 controls seen between November 1992 and November 1993 at the Istituto Dermopatico dell'lmmacolata (IDD) in Rome, were enrolled into the study. Cases were outpatients with first diagnosis of hyperidrosis, chronic urticaria, generalized pruritus or alopecia areata. Controls were outpatients seen in the same period of time with first diagnosis of pigmenled nevi, keratosis or mycosis. The presence and weight of life stress events were assessed by u standard precoded questionnaire based on the Schedule of Recent Experiences (SRE) and on the Life Experiences Survey (LES). The attachment style was assessed by a modified version of the Shaver and Hazan questionnaire about feelings in a love relationship. We calculated 3 scores for each individual and classified study subjects in 2 groups: 1) "free" (= secure attachment); 2) "not free" (not secure attachment: anxious-ambivalent or avoidant). Questionnaires were self-administered in the presence of a trained psychologist. Adjusted odds ratios (OR) were calculated using a multiple logistic function. Results No association was found between the different stress scores and the skin diseases considered. The crude odds ratio for life stress events in the previous year was 1.4 (95% CI 0.8–2.7). After multiple adjustment for age, sex, marital status and education, the estimated OR was 1.6 (95% CI 0.8–3.0). One significant association emerged between the adult attachment style defined as “not free” and psychosomatic skin diseases: the adjusted OR was 4.0 (95% CI 1.4–12).