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71.
按随机抽样原则选择湖北恩施土家族人598名观测了眼的表面形态。该民族大部分人两眼位置适中,虹膜褐色,眼裂水平,开度中等,无蒙古褶,双睑;多为细窄眼型或中等眼型;眼的各径男大于女,一般存在性别差异;随年龄增加,眼型由中等型向细窄型转化,根据眼外形特征和聚类分析推测,土家人眼属于南、北方民族间的过渡型。  相似文献   
72.
A retrospective case-control study of 50 MRSA-positive patients was carried out during an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) at an acute general hospital in London. Controls were randomly selected from MRSA-negative patients admitted during the outbreak period. Risk factors investigated included length of admission prior to screening, number of ward changes, main diagnosis, extent of staff contact, pressure sores, surgical and other invasive procedures and antibiotic treatment. Outcome variables examined were rates of infection (versus colonization) with MRSA and mortality. Patients with MRSA were in hospital longer before microbiological specimens were taken and moved wards more often than controls. In a logistic regression analysis, length of stay in hospital, pressure sores, physiotherapy and surgical procedures were associated with a significantly increased risk of acquiring MRSA. Odds ratios (and 95% confidence intervals) for having acquired MRSA were: 8·3 (1·02−71·43) if a patient had pressure sores; 3·7 (1·10−12·5) if they received physiotherapy; and 3·2 (1·82−10·0) if they underwent surgical procedures. The rate of clinical infection amongst patients with this strain of MRSA was 26% and included life-threatening infections such as septicaemia, underlining the potential virulence of MRSA. Surgery and physiotherapy may have been markers of debility. Physiotherapy was probably a marker of increased rates of contact with all hospital staff, and high standards of hand hygiene should be promoted amongst all staff as the most important factor in controlling an outbreak of MRSA. Good bed management is essential for hospital infection control.  相似文献   
73.
The duration of the late exteroceptive suppression period (ES2) of temporal muscle EMG activity has been reported to be reduced in patients suffering from chronic tension-type headache. Methods of recording and analysing ES2 have varied between centers and reproducibility of results within subjects , although insufficiently studied, has generally been poor. ES2 was investigated in 30 healthy subjects, using a computerized technique of recording, rectifying and averaging the EMG signals. Hour to hour and week to week variations of ES2 durations were calculated, and the influence of pain during a cold pressor test and of sustained muscle contraction on ES2 durations was investigated. The intra-individual variation of ES2 durations was 16.0% from hour to hour and 20.7% from week to week. The inter-individual variation was 36.7%. The present method for analysis of ES2 periods proved to be reliable, as the intra-observer variation was 4.2% and the inter-observer variation 4.6%. ES2 periods were significantly shorter on the first compared to the second day of examination ( p = 0.006) and during experimental pain ( p = 0.0005). We recommend the use of the computerized averaging technique in future studies and caution against the dependence of results upon factors such as conditioning and pain.  相似文献   
74.
Obesity in youth and middle age and risk of colorectal cancer in men   总被引:5,自引:0,他引:5  
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services.  相似文献   
75.
76.
To determine the structural perturbations induced by the CαH→Nα exchange in aza-peptides, we have examined by H NMR and IR spectroscopy various derivatives of the aza-analogues of alanine, aspartic acid and asparagine in different organic solvents with increasing polarity. Their general formulas are: R'-AzXaa-NR2R3, R'-Pro-AzXaa-NR2R3 and R-AzXaa-Pro-NR2R3 (where AzXaa denotes the aza-analogue of the amino acid residue Xaa = Ala, Asp, Asn; R = Boc, Z; R2, R3= H, Me, iPr). The aza-analogue of an amino acid residue appears to be a strong p-turn-inducing motif, and the AzAsn carboxamide side-chain is capable of interacting, as a proton donor, with the preceding peptide carbonyl group.  相似文献   
77.
目的:探讨胃复春片治疗慢性胃病患者前后生长抑素内分泌细胞(D细胞)数量变化。方法:用免疫组化酶链亲合素过氧化酶复合技术(SABC)对患者治疗前后胃粘膜组织的D细胞染色,观察治疗前后D细胞的形态和数量变化。结果:经胃复春片治疗后,患者胃窦粘膜D细胞阳性数及强阳性率均明显下降,有显著意义。结论:胃复春片对慢性胃病患者生长抑素D细胞有调整作用。  相似文献   
78.
Clinical Evaluation of a New Type of Centrifugal Pump   总被引:2,自引:0,他引:2  
Abstract: The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart surgery with a centrifugal pump or a roller pump. During surgery, hemodynamic and hematological data were obtained. A pulsatile assist device in the pump circuit was used in patients with severe heart disease. There was neither operative death nor hospital mortality, and there was no difference with regard to hemodynamic data between the two groups. The centrifugal pump group, however, had significantly lower hemolysis, especially during prolonged cardiopulmonary bypass. This centrifugal pump could also create sufficient pulsatile flow with a pulsatile assist device. Postoperative macroscopic and microscopic findings demonstrated the smooth surface of the pump without thrombus formation. This centrifugal pump system might be useful for prolonged cardiopulmonary bypass.  相似文献   
79.
目的 研究应用计算机数据库技术及先进统计分析方法,对阳江高本底地区10多万人20余年的健康随访研究资料和剂量学调查资料进行储存、管理和分析。方法 通过调研和比较分析,确定采用Foxbase系列数据库管理系统按专题建立数据库,借助于ID号实现记录连接;一般统计分析由SAS完成;交叉分组人年列表由Epicure中的Datab完成;癌症相对危险分析用AMFIT程序。结果 建立了40MB的各专题研究库,主要包括:10余万人的人口学数据库(1979~1995)、1.2万人的死因数据库(1979~1995)和526个村庄6783户、5273人的剂量数据库。提出了动态群组研究资料(1979~1986)与固定群组研究资料(1987~1995)的合并方法:首选方法是建立假想的基于记录连接的以1979年为起点的(固定)群组。另一方法是将不同阶段群组研究的人年表分层直接相加。计算了每个成员基于卧室内、起居室内、室外村平均剂量率与性别-年龄别居留因子的累积剂量。完成了以性别、atainedage、随访年代及剂量交叉分组的人年列表,对癌症死亡资料(1979~1990)进行了危险分析。结论 应用计算机数据库管理系统与统计分析技术使阳江高本底地区研  相似文献   
80.
This is a report on a comparative study of the reactivity of TRUE Test and Finn Chamber patch test techniques. 413 patients attending a contact dermatitis clinic in Singapore were simultaneously patch tested with panels 1 and 2 of the TRUE Test standard series and with corresponding allergens (Hermal, Hamburg) using Finn Chambers. The left/right application of the TRUE Test and Finn Chambers was randomized. The concordance of positive patch test reactions to the 2 test techniques was studied. The number of patient with positive reactions was 38% and 42% for TRUE Test and Finn Chamber techniques, respectively (n.s.). The overall concordance of positive patch test reactions was 64% (209/328). 13% (42/328) of positive reactions appeared on TRUE Test only and 24% (77/328) on Finn Chamber only. When only relevant positive reactions were considered, the concordance rate was 67%; 11.6% of positive reactions appeared on TRUE Test only and 21% on Finn Chamber only. Positive reactions to p-phenylenediamine (PPD) and neomycin were more frequent with the Finn Chamber technique than with TRUE Test, i.e., false negative reactions to PPD and neomycin were more likely to occur with TRUE Test. It appeared that the TRUE Test and Finn Chamber techniques were comparable when used for patch testing. However false negative and false positive patch test reactions can occur when using either technique.  相似文献   
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