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51.
Three different domains of behavioral action of ethanol (ETOH) were examined in a battery of seven inbred strains and in the selectively bred Long-Sleep (LS) and Short-Sleep (SS) mice. Sedative effects were examined with the loss of the righting reflex test at 3.8 g/kg. The variation among inbred strains was only half the size of the difference between LS and SS mice which were selectively bred for extremes in this phenotype; such a result is expected for phenotypes controlled polygenically. Blood ETOH levels at waking from the narcosis also showed a range of differences among the inbred strains that was less than the LS/SS difference. Ataxia was measured with the grid test, and the inbred strains fell into two groups, resembling the highly ataxic LS line, and the less ataxic SS line. Biphasic effects of ETOH on locomotor activity were strongly genotype dependent. Variation in degree of activation/disinhibition produced by doses up to 1.5 g/kg (IP) ranged from no activation, in the C57BL/6Abg strain, to a stimulation effect in the MOLD/RkAbg strain which was larger than that seen for SS mice. The patterns of strain differences for both ataxia and activation were highly different from the duration of loss of righting reflex measure, suggesting multiple independent genetically based sensitivities to ETOH.  相似文献   
52.
The association between severe aplastic anemia (AA) and DR2 antigen seems to be well established. However, since discrimination between two DR2-associated splits, namely DR15 and DR16, rarely was performed, it remains unclear whether one or both of these subvariants are responsible for AA susceptibility. In this study, we have analyzed the HLA-DR allelic distribution in a group of 37 AA patients of slavic origin from North-Western Russia. The experimental design included PCR-based amplification of DRB-specific sequences, followed by reverse dot-blot hybridization of the biotinylated PCR-product with the set of sequence-specific oligonucleotide probes. HLA-DRB alleles were identified by non-radioactive enzymatic reaction, then standard serological specificities of HLA-DR antigen were estimated according to the WHO nomenclature. Whereas DR15 subtype occurred more often in the patients (23.0% vs. 13.3%, p< 0.05), DR16 split did not show the same tendency. The results, show the overall predominance of HLA-DR2 specificity (DR15+DR16) did not reach statistical significance (24.4% vs.17.5%, p<0.2). Thus, we conclude that repeatedly reported DR2 frequency increase in AA patients is mainly attributed to the prevalence of DR15 subtype.  相似文献   
53.
We present results from a simulation study for the estimation of a common odds ratio in multiple 2 × 2 tables when the data are correlated within clusters. We model the correlation of the data by the beta-binomial distribution. Through a simulation study, we compare the Mantel—Haenszel estimator with Rao and Scott'S estimator in terms of their biases, observed variances, relative efficiencies of their variances and 95 per cent coverage proportions. We limit the simulation study to the case where there are the same number of subjects in each cluster and the same number of observations in each row of each stratum. When ρ = 0, we recommend use of the Mantel—Haenszel estimator γMH with an unadjusted variance and Rao and Scott'S estimator γ with a pooled design effect. In general, when ρ >0, we recommend the Mantel—Haenszel estimator γMH with an adjusted variance and Rao and Scott'S estimator γ with a pooled design effect.  相似文献   
54.
Cancer mortality was analysed in 3282 elderly subjects aged 65 years from 2 cohorts of general population having different life-style patterns. They took part in the CASTEL (CArdiovascular STudy in the ELderly), a 12-year lasting prospective Italian study. The aim of the present analysis was to identify the items able to influence cancer mortality. A biochemical profile and a questionnaire on lifestyle were collected. Continuous items were averaged and compared with analysis of variance, frequencies with the Pearson's 2 test. Mortality was recorded yearly for 12 years from the Registrar's Office and causes of death double-checked by consulting medical case sheets and family doctors' files. The influence of items on mortality was evaluated with the Cox multivariate analysis. Relative risk (RR) of each item was adjusted for confounders. Age, gender, tobacco smoking, the presence of respiratory symptoms, low body mass index in males, serum alanine transaminase (ALT) and alkaline phosphatase (ALP), as well as the town of residence, were powerful predictors of cancer mortality. In the entire population, 12-year overall mortality was 49.4%, cardiovascular 22.8%, and neoplastic 11%; the latter was higher in males than in females (15.7% vs. 7.9%, p < 0.00001). In subjects with respiratory symptoms neoplastic mortality was 11.6% (RR: 1.47) vs. 9.7% in those without symptoms (p < 0.01). Subjects with very low cholesterol ( 178 mg/dl), those with high uric acid ( 8.7 mg/dl) and males with low body mass index ( 22.7 kg/m2) has an increased risk of cancer mortality. RR of cancer mortality increased with increasing ALT or ALP. It was 1 in those having ALT and ALP between 9 and 41.2U/I, 1.41 in those exceeding this latter level and < 1 in those below 9U/I. RR of ALP had a similar trend, the best protective cut-off value being <106 and the worst one > 177U/I. When both serum enzymes were simultaneously raised, RR of cancer mortality increased to 2.84.  相似文献   
55.
The QT interval was measured in 12 normal and 7 aborted sudden infant death syndrome (SIDS) infants in rapid eye movement (REM) and quiet sleep at monthly intervals through the age of 4 months. An accuracy of better than 2 msec was assured by high resolution of the digitized signal and calibration of each QT measurement with an accurately generated time code. In contrast to current speculations, the QT index was significantly smaller in the infants with aborted SIDS than in the normal infants in both REM and quiet sleep (P less than 0.05). In addition, as in normal infants, the QTc was smaller in REM than in quiet sleep (P less than 0.01). Although these results offer no support for the hypothesis that SIDS results from prolongation of the QT interval, they suggest that aborted SIDS infants have a functional abnormality in the autonomic nervous system.  相似文献   
56.
57.
The majority of Australia's general practitioners are now believed to be using a computer to support clinical practice. This technology has the potential to deliver evidence-based clinical practice guidelines to the GP during consultations. If clinical practice guidelines are to be incorporated into electronic medical record systems, to assist clinical decision making at the point of care, guideline development will need to be significantly revised. Computerised clinical decision support at the time of consultation may become a major method for continuing medical education for Australian GPs.  相似文献   
58.
目的研究富含anthocyanin的水果提取物对血管内皮细胞产生PGE2的影响。方法将人类正常的血管内皮细胞CRL-2606在Kaighn’s F12K培养基中(补加有10%FBS,0.1mg/ml肝素,0.03mg/ml的ECGS,50μg/ml链霉素和500U/ml青霉素)37℃、5%CO2的条件下培养至接近融合,然后在含有从水果中提取出的anthocyanin的F12K培养基中添加或不添加100ng/mlLPS,继续培养18小时,测定细胞生存率,并将培养液离心,收集上清液,用STAT-Prostaglandin E2 EIA Kit试剂盒测定培养基上清液中的PGE2浓度。结果当CRL-2606细胞暴露于300μg/ml或以上的Chokeberry提取物中时,细胞的生存率低于60%,且表现出一定的剂量效应关系。而50~400μg/ml的蓝莓提取物和100~700μg/ml的黑醋栗提取物未显示细胞毒性。LPS刺激可使细胞PEG2释放量增加一倍以上,蓝莓提取物可明显抑制由于LPS刺激引起的PGE2释放增加,100μg/ml的蓝莓提取物可完全抑制此作用而使其含量维持于正常水平。700μg/ml的黑醋栗提取物对处于LPS刺激下的CRL-2606细胞具有一定的抑制PGE2释放作用。而对于处于LPS刺激下的细胞,500tμg/ml以上的Chokeberry提取物能抑制PGE2的释放。结论富含anthocyanin的黑醋栗、蓝莓以及Chokeberry提取物可以抑制由LPS刺激引起的血管内皮细胞释放PEG2增加的作用,具有一定的抗炎、抗氧化作用。  相似文献   
59.
Background and Aims:  Environmental modification is a strategy widely recommended in many falls prevention programs. However the effectiveness of such a strategy has not been well established. This study aimed to evaluate published research related to falls prevention and environmental modification for older people.
Method:  A review of research conducted between 1993 and 2004 was undertaken. Ageline, Cinahl and OvidMedline databases were searched using falls prevention, home modifications, environmental modifications and occupational therapy as key words.
Results:  Eighteen articles were found relating to community and institutional dwellings and the relevance of environmental modifications.
Conclusion:  There is some evidence to support the use of environmental modification as a strategy in falls prevention for older people particularly in association with multidisciplinary/multifactorial programs targeted to those people with a history of falls.  相似文献   
60.
Reducing risk factors for patients with vascular disease can reduce the subsequent incidence of cerebro-cardiovascular disease. While physicians have had extensive training in the importance of atherosclerotic vascular disease risk factor modification, evidence suggests that they systematically miss opportunities for clinical prevention during routine practice. The aim of this study was to identify whether physicians felt confident in their knowledge and effectiveness regarding counseling patients to reduce cardiovascular risk and to determine barriers to prevention interventions in the office setting. Surveys were mailed to 509 physicians affiliated with an academic community hospital. Nonrespondents were sent reminders and a second survey. Comparisons were made using chi-square analysis. Two hundred and five surveys were returned (40.3%). Thirty-six percent of physicians felt knowledgeable about weight management techniques, compared to 3% who were confident that they succeeded in their practice (p < 0.001). Similar patterns were found for Tobacco Cessation (62% versus 14%, p = 0.001), Alcohol Reduction (46% versus 7%, p < 0.001), Stress Management (35% versus 5%, p < 0.001), Exercise (53% versus 10%, p < 0.001), Nutrition (36% versus 8%, p < 0.001), Diabetes Management (48% versus 23%, p < 0.001), Blood Pressure Management (57% versus 43%, p < 0.001) and Lipid Management (59% versus 38%, p < 0.001). We identified a significant gap between physician confidence in their knowledge about risk factors and their effectiveness at providing counseling and obtaining results in their office. Most physicians felt that the routine office follow-up visit was an ineffective method for instituting vascular risk factor reduction. Alternate settings for risk factor reduction may be needed for improving atherosclerosis prevention.  相似文献   
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