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排序方式: 共有10000条查询结果,搜索用时 328 毫秒
31.
AnAnalysisofChromosomeonSterilityCausedbyAzoospermiaorOligospermia¥WuMeiheng;TangWingnuo.(ACTAACADEMIAEMEDICINAENANJING,1995(... 相似文献
32.
B. Hubner G. Lehnert K. H. Schaller D. Welte J. Angerer 《International archives of occupational and environmental health》1992,64(4):261-264
Summary Twenty-two persons (20 men and 2 women) were examined for their external and internal exposure to the glycol ether 1-methoxypropan-2-ol (PGME) during the production, leak testing and mounting of brake-hoses. For the measurement of external exposure, personal air monitoring was the method of choice. Average concentrations of PGME of 82.2 mg/m3 (22.3 ppm), 68.6 mg/m3 (18.6 ppm) and 11.3 mg/m3 (3.1 ppm) were found in the air of the brakehose production, leak test and mounting areas, respectively. For the estimation of internal exposure to PGME, this glycol ether was measured in both urine and blood. The biological samples were taken post-shift. The highest internal exposure levels were found in the brakehose production section and in the leak test area. The average post-shift concentrations for PGME in workers in the brakehose production section were 4.6 mg/l in urine and 13.5 mg/l in blood; the corresponding figures for workers in the leak test area were 4.2 mg/l in urine and 11.0 mg/l in blood. In blood and urine samples of workers engaged in the mounting area, PGME levels were below the detection limits. The elimination kinetics of PGME were also studied in three highly exposed persons, and mean excretion half-lives of PGME of approximately 4.4 h were found. On the basis of our results we made a rough calculation of a future biological tolerance value: we would except that concentrations of 38-109 mg per litre of blood and 10–31 mg per litre of urine would correspond to the German MAK value for PGME (375 mg/m3). 相似文献
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In the past few years there have been numerous publications which have stressed the value of the dexamethasone suppression test (DST) as a diagnostic marker of endogenous depression. Our own studies in 333 psychiatric inpatients and 121 healthy subjects did not reveal a differential diagnostic use for the DST. This result is in good agreement with other results in the literature. Our data demonstrate that intervening variables such as severity of illness, weight loss, sleep disturbances, situational stress, drug and alcohol withdrawal, and the pharmacokinetics of dexamethasone have an important influence on DST results, regardless of the diagnostic classification. 相似文献
36.
目的 :为粤西地区血小板聚集率的临床检测提供参考标准。方法 :采用北京普利生仪器有限公司生产的 L BY-NJ型多功能血液凝聚仪。以终浓度 2 .5 μmol/ L ADP为诱导剂 ,对 6 38例正常人按年龄、性别分组 ,分别检测血小板 1m in、3min、5 min及 Max聚集率 ,并进行统计学分析。结果 :各年龄组男女性别 PAG无显著性差异 ( P>0 .0 5 ) ;小于 35岁年龄组与 35~ 5 5岁年龄组比较 ,PAG无显著性差异 ( P>0 .0 5 ) ;35~ 5 5岁年龄组与大于等于 5 5岁年龄组比较 ,1min及 3mim PAG存在显著性差异 ( P<0 .0 5 )、5 min及 Max PAG相差非常显著 ( P<0 .0 1) ;小于 35岁年龄组与大于等于5 5岁年龄组比较 ,PAG有非常显著性差异 ( P<0 .0 1) ;小于 5 5岁年龄组与大于等于 5 5岁年龄组比较 ,PAG差异有极显著性意义 ( P<0 .0 1或 P<0 .0 0 1)。结论 :5 5岁以上年龄组与 5 5岁以下年龄组的 PAG结果 ,可作为粤西地区同类方法PAGT的正常参考值供临床检测参考 相似文献
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Magnetic susceptibility, as a physical property of materials, plays important roles in many physical, chemical, engineering, and medical applications. Its quantification becomes of significant interest when MRI becomes a commonly used technique in biomedical applications. A general method is presented here for quantifying arbitrary magnetic susceptibility distributions in a localized region on the basis of first principles of magnetic induction field distributions in space. A proof of the concept was demonstrated by computer simulations. The study establishes the methodological basis for quantitative magnetic susceptibility imaging with MR. 相似文献
39.
造影剂到达腹主动脉的峰值大小与患者因素的关系 总被引:3,自引:0,他引:3
目的探讨造影剂到达腹主动脉的峰值大小与患者因素之间的关系。方法108例患者以2.5ml/s注射欧乃派克(300mgI/ml)20ml,12s后采用testbolus技术在腹腔干水平同层动态扫描腹主动脉,用dynamic evaluation软件测得腹主动脉的峰值大小,采用单因素回归分析和多因素逐步回归分析法研究患者的性别、年龄、身高、体重、心率、血压、注射位点、达峰时间及是否有心脏病、糖尿病、或化疗史对造影剂到达腹主动脉峰值大小是否有影响及影响程度。结果造影剂到达腹主动脉峰值大小,在男性平均比女性低;其随年龄、身高、体重、达峰时间的增加而逐渐降低,注射位点在手背静脉其值平均比在肘部静脉低;其不受心率、血压、是否有心脏病、糖尿病或化疗史的影响。参考公式:峰值大小(HU)=383.8400-身高(cm)×1.0909-体重(kg)×0.6760 注射位点×16.7878-达峰时间(s)×1.6882。结论可根据患者的性别、年龄、身高、体重、注射位点和达峰时间来适当调整患者CT血管成像时造影剂用量。 相似文献
40.
N R Hill P C Hindmarsh R J Stevens I M Stratton J C Levy D R Matthews 《Diabetic medicine》2007,24(7):753-758
AIM: As the practice of multiple assessments of glucose concentration throughout the day increases for people with diabetes, there is a need for an assessment of glycaemic control weighted for the clinical risks of both hypoglycaemia and hyperglycaemia. METHODS: We have developed a methodology to report the degree of risk which a glycaemic profile represents. Fifty diabetes professionals assigned risk values to a range of 40 blood glucose concentrations. Their responses were summarised and a generic function of glycaemic risk was derived. This function was applied to patient glucose profiles to generate an integrated risk score termed the Glycaemic Risk Assessment Diabetes Equation (GRADE). The GRADE score was then reported by use of the mean value and the relative percent contribution to the weighted risk score from the hypoglycaemic, euglycaemic, hyperglycaemic range, respectively, e.g. GRADE (hypoglycaemia%, euglycaemia%, hyperglycaemia%). RESULTS: The GRADE scores of indicative glucose profiles were as follows: continuous glucose monitoring profile non-diabetic subjects GRADE = 1.1, Type 1 diabetes continuous glucose monitoring GRADE = 8.09 (20%, 8%, 72%), Type 2 diabetes home blood glucose monitoring GRADE = 9.97 (2%, 7%, 91%). CONCLUSIONS: The GRADE score of a glucose profile summarises the degree of risk associated with a glucose profile. Values < 5 correspond to euglycaemia. The GRADE score is simple to generate from any blood glucose profile and can be used as an adjunct to HbA1c to report the degree of risk associated with glycaemic variability. 相似文献