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81.
不同培养基对肠球菌检出率的影响 总被引:3,自引:1,他引:2
用pH9.6葡萄糖肉汤、6.5%NaCl琼脂平板、3%—5%羊血琼脂平板三种不同培养基,从同一份样品中分离肠球菌,检出率有显著差别。pH9.6葡萄糖肉汤对检样选择性增菌后,再用6.5%NaCl琼脂平板分离肠球菌,其检出率明显高于现正普遍用于肠球菌初代分离的3%~5%血琼脂平板(P<0.05),也高于单纯使用6.5%NaCl琼脂平板(P<0.05);后两者间无显著差别(P>O.05)。属中种的构成在不同培养基上检出情况也不同。 关键词:培养基 肠球菌 检出率 肠球菌广泛存在于自然界,是水、空气、尘 相似文献
82.
我国正常中老年人心率变异分析 总被引:10,自引:0,他引:10
心率变异分析(HeartratevariabilityHRV)目前被认为是一项预测心性猝死,特别是预测心肌梗死后病人猝死危险性的独立、敏感的指示。目前尚缺乏大样本HRV时相分析正常值范围。本研究采用英国OXFORD公司MedilogEXCEL长程心电图分析系统,分别用标准差法(Standarddeviation,SD)和HRV指数法(HRVIndex)对120名(男:女=97:23)40一70岁(平均57岁,<60岁者66人,≥60岁者54人)健康人的24小时HRV值进行测算。其结果为,SD:118.15±15.37ms.HRVIndex18.62±2.31;中年组(<60岁)平均SD:;122.03ms.平均HRVIndex:20.16;老年组(≥60岁)平均SD:107。92ms.平均HRVIndex:16.41。两种方法的结果均显示。HRV日间低于夜间,中年人高于老年人,3小时9时HRV最低,与晨间冠心病急性发作事件高峰相吻合。本文并对HRV的昼夜变化规律及其意义进行了初步探讨。 相似文献
83.
84.
M. Estryn-Behar B. Kapitaniak M. C. Paoli E. Peigne A. Masson 《International archives of occupational and environmental health》1992,64(2):131-139
Summary The aim of this study was to evaluate the level of physical capacity in a female hospital population of Paris and its suburbs. A total of 1505 women working in the selected departments filled in a questionnaire concerning their working conditions, life habits and health and also attended a medical examination. The effort test performed consisted in flexing the legs 20 times with the chest held straigt, in 40 s. The heart rates were measured for the first, the second and the third minutes of recovery (first 15 s multiplied by 4). The blood pressure was measured just after the heart rate, for the first and the third minute. Recovery indices have been constituted from the results. The respective weights of anthropometric and sociodemographic risk factors for recovery indices were studied in multiple logistic regression models. The classification enables us to consider about 25%–30% of our population as having a satisfactory physical capacity, about 26%–27% as having an acceptable capacit, and about 24%–27% as having a weak capacity. About 21% of the population presented an excessive pressure reaction and 44% a questionable pressure reaction. Our results concerning the level of physical capacity of the female nursing staff should be taken into account especially in the future planning of work loads and architectural choices, which must avoid excessive physical burdens in relation to this level. An improvement in the level of physical capacity could be envisaged as well. 相似文献
85.
本文在研究等剪切场中剪切率与剪切时间对全血血小板自发聚集性的影响时发现,随着剪切时间的延长,血小板自发聚集率与剪切率的关系逐渐由正相关转化为负相关;而随着剪切率的增加,血小板自发聚集率与剪切时间的关系也由正相关转为负相关;剪切率在46 S~(-1)或剪切时间在20分钟时,血小板的自发聚集率与剪切时间或剪切率无关。 相似文献
86.
Exhaled nitric oxide in healthy children: Variability and a lack of correlation with atopy 总被引:1,自引:0,他引:1
Nitric oxide (NO) is a free radical produced by several lung cells via the enzyme nitric oxide synthetase (NOS) and can be easily measured in exhaled air by chemiluminescence analysis. As the iso-enzyme iNOS may be induced by cytokines and endotoxin, NO is elevated in several chronic inflammatory airway diseases. Prior to using exhaled nitric oxide (eNO) as a non-invasive marker of airway inflammation in daily routine, the role of possibly influencing factors such as age, time of the day, smoking exposure and intra-individual variability have to be clarified. NO concentrations were measured in 107 healthy children aged 4–18 years at an expiratory flow of 184 ml/s. Spirometry and a skin-prick test were performed and a questionnaire on family history of atopy, personal symptoms of atopic disease and smoke exposure was completed. For intra-individual variability nitric oxide was measured in six children three times daily on 6 consecutive days. Median eNO concentration was 5.7 p.p.b., and increased significantly with age but did not vary with gender. No correlation was found between eNO and smoke exposure, positive skin-prick test, FEV 1 , MEF25 and time of the day. There was no circadian rhythm found in the six children measured on 6 consecutive days, but the eNO showed an intra-individual coefficient of variation of 25.9%. With the help of a two-compartment model of the lung the alveolar NO concentration was estimated to be 4.1 p.p.b and was shown to be constant with age, whereas the airway part of NO steadily increased with age. When comparing eNO values with standardized measurement techniques, the age of the children and the large intra-subject coefficient of variation have to be taken into account, whereas in healthy children subject-specific factors such as atopic history, gender and skin test reactivity did not affect eNO measurement. 相似文献
87.
本文对上海市区35个生产车间的蟑螂侵害率进行调查,观察到生产性车间有黑胸大蠊及美洲大蠊两种,侵害率达58.85%。在20个有蟑螂的车间内都有黑胸大蠊栖息,平均密度10.65只/m~2;而美洲大蠊仅见于8个车间,聚集性较强,平均密度达38.50只/m~2。对较干燥车间或地下室用1%乙酰甲胺磷糖水毒杀蟑螂,24h杀灭率达95.89%。 相似文献
88.
Marko Korosec Ignac Zidar Dik Reits Craig Evinger Frans Vanderwerf 《Movement disorders》2006,21(8):1248-1251
We examined eyelid movements during spontaneous, voluntary, and trigeminal reflex blinks in 16 patients with mild to moderate Parkinson's disease (PD) off medication and 14 controls. Voluntary and reflex blink amplitudes tended to be smaller than normal for PD patients, whereas eyelid kinematics (amplitude-maximum velocity relationship) for all three blink types were normal. Spontaneous blink rate was less than normal for 10 patients and abnormally high for 6 patients. A significant positive correlation between spontaneous blink amplitude and blink rate was found. These observations suggest that PD modifies the gain of a premotor blink circuit shared by spontaneous, voluntary, and reflex blinks. 相似文献
89.
报告102例进展期胃癌术后患者,随机进行3组不同化疗方案并经平均随访10.7年的结果。所有病例均为1983年5月到1985年5月间手术者。术后随机给予单一5-FU、5-FU+CCNU和MTX+MMC+5-FU三组不同化疗。随访至1994年12月止,死亡77例,存活25例。结果3、5和10年总生存率分别为42.1%;29.4%和24.5%。三组间比较,总自下而上率并无显著差异(P〉0.05),但中位 相似文献
90.
玉溪市农村室内鼠类及其体外寄生蚤类调查 总被引:1,自引:0,他引:1
笔者于1992年2月至1993年1月,在玉溪市两个自然村室内进行了鼠类及体外寄生蚤类调查研究。鼠类年均捕获率7.25%;褐家鼠为优势种,占73.49%,捕获率高峰期在9月;黄胸鼠和小家鼠为常见种,捕获率高峰期分别在3和4月。3种家鼠年龄孕鼠率为14.57%,平均胎仔数为7.3只,10月为全年生殖高峰。 相似文献