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91.
Objective: Previous studies indicate that a poor family environment might affect vulnerability for the later manifestation of psychotic illness. The current study aims to examine family functioning prior to the onset of psychosis. Method: Subjects were 42 948, 17‐year old males with behavioural disturbances who were asked about the functioning of their family by the Israeli Draft Board. Data on later psychiatric hospitalizations were obtained from a National Psychiatric Hospitalization Registry. Results: Poorer self‐reported family functioning was associated with greater risk for later hospitalization for psychosis [adjusted hazard ratio (HR) = 1.16, 95% CI = 1.05–1.27], with a trend in the same direction for schizophrenia (adjusted HR = 1.1, 95% CI = 0.98–1.24). Conclusion: In male adolescents with behavioural disturbances, perceived poorer family functioning is associated with increased risk for non‐affective psychotic disorders and schizophrenia. These data do not enable us to determine if perceived familial dysfunction increases vulnerability for psychosis, if premorbid behavioural abnormalities disrupt family life, or neither.  相似文献   
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目的 了解DNA指数 (DI)与人肝细胞系生物功能之间的关系。探讨DI值可否作为人工肝生物材料的初步筛选指标。方法 收集国内 9株人工肝细胞系 ,分别编号为细胞系 1- 9(CL1-9)。分别培养后获取细胞。取正常人全血分离淋巴细胞 ,作为正常二倍体对照。以流式细胞仪(FCM)测定 9株人肝细胞系DI值作为分化指标 ,判断人肝细胞系的分化情况。人肝细胞系分别接种1.2× 10 6个细胞 ,收集其培养生长旺盛、生物功能良好的第 5天时的培养上清液 ,测定上清液中的尿素、人白蛋白和安定含量 ,计算细胞系尿素合成、人白蛋白合成和安定转化量。进行DI值和肝功能指标间的相关性分析。CX7自动生化分析仪测定尿素浓度 ;用人白蛋白放免试剂盒经改良后采用放射免疫抗原竞争法测定人白蛋白浓度 (人白蛋白与牛血清白蛋白无交叉反应 ) ;培养上清中另加入 4 μg/ml安定作肝细胞药物代谢功能指标 ,提取后以 75 2型紫外分光光度计测定安定含量。采用双变量相关与回归分析方法进行统计学分析。结果 人肝细胞系DI值与人肝细胞系尿素合成量、人白蛋白合成量及安定转化量均呈线性相关 ,相关系数分别为 - 0 .94 37、- 0 .8795、- 0 .9386。结论 CL1分化程度最高 ,生物功能最好 ;DI值可以作为人工肝生物材料的初步筛选指标  相似文献   
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Reliability of Sleep Measures   总被引:2,自引:0,他引:2  
J. Moses    A. Lubin    P. Naitoh    L. C. Johnson 《Psychophysiology》1972,9(1):78-82
The reliability of sleep measures was calculated over two nights (and within the nights) for 20 young adult males. Percent time in stages 1, 2, 3, and 4, percent movement time, number of movements, and number of stage changes were significantly correlated between Ss over nights. The percent REM time and REM cycle duration were not significantly correlated over nights. Within Ss, the length of the REM period had a significant negative correlation with the length of the preceding NREM period but not with the following NREM period. These data raise questions as to the use of the standard sleep measures as reliable human traits in young male adults.  相似文献   
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OBJECTIVES: To investigate the impact of measuring a single home then imputing information from another home among subjects who lived in two homes in a subset of the National Cancer Institute/Children's Cancer Group (NCI/CCG) investigation of residential exposure to magnetic fields and risk of childhood leukaemia. METHODS: Each subject's summary time weighted average (TWA) exposure was derived from measurements of two homes, weighted by the fraction of the reference period lived in the residence. The three cost efficient field work strategies examined were measuring: (a) the longer lived in home; (b) the currently lived in home; and (c) the former lived in home. Two different methods were used for imputing the missing values: (a) control mean imputation, (b) status specific mean imputation. The subject's summary exposure to magnetic fields estimated with each approach was compared with the subject's TWA calculated from measurements in both homes. The association between estimated exposure to magnetic fields and the risk of leukaemia under different approaches was examined with unconditional logistic regression analysis. RESULTS: The Pearson correlation coefficient between the two measurements within subjects was 0.31 (p < 10(-4), indicating a lack of independence of measurements. Differences were found between mean exposures in current and former homes of cases, and between longer and shorter lived in homes of controls. All methods with measurements from one of the homes in conjunction with imputation of measurements for the second home led to marked attenuation of risk estimates at the highest exposure category, particularly when measurements from current homes were used and those from former homes were imputed. CONCLUSION: Results argue against attempting to estimate lifetime magnetic field exposure from imputed values derived from current residences to fill in gaps caused by unmeasured residences previously lived in.  相似文献   
99.
OBJECTIVE: The aim of the present study was to compare demographic and clinical characteristics of primary peritoneal carcinoma (PPC) to ovarian carcinoma (OvC) with regard to BRCA mutation frequencies. METHODS: Incident cases of histologically confirmed cancer of the ovary or peritoneum diagnosed in Israeli Jewish women between March 1, 1994, and June 30, 1999, were identified within the framework of an ongoing nationwide epidemiological study of these neoplasms in Israel. The present study comprises 609 (81.5% of 747) Jewish women with epithelial stage III-IV OvC and 68 (77.3% of 88) Jewish women with PPC who were genetically tested for the BRCA mutations. Data from each patient were collected by the aid of a prestructured questionnaire and medical records. Blood samples or tumor tissue was tested for the 185delAG and 5382insC mutations in BRCA1 and the 6174delT mutations in BRCA2. RESULTS: A carrier rate of 28% of any BRCA 1/2 mutation was observed among the PPC group and of 30% among the invasive stage III-IV OvC. No differences were found between PPC and OvC neither in the overall distribution of BRCA1/2 mutation carrier rates nor according to type of mutation, age, ethnic origin, and histologic subtype. Among women with a positive family history, a higher rate of mutation carriers was observed in the PPC group compared to the OvC group (72.7 vs 43.8%, respectively, P = 0.07). CONCLUSIONS: The similar frequency distribution of BRCA1/2 mutations in PPC and OvC observed in the present study indicates that these mutations may predispose to PPC as well and that this neoplasm is part of the hereditary breast-ovarian cancer syndrome.  相似文献   
100.
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality.  相似文献   
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