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11.
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50例正常生育力男子精液和血液激素的一年动态观察 总被引:5,自引:0,他引:5
作者对南京市50名正常男子,每月1次、连续12个月测定了精液常规、某些精液生化和血清激素水平。结果表明:精子密度每次之间波动范围较大,冬季数值比夏季显著为高(P<0.01)。其它指标包括正常形态精子、活动精子、前向运动级别、精液果糖、硷性磷酸酶、酸性磷酸酶及血清,FSH LH T 则变动不显著。精液常规中除精子密度和各参数关系不明显外,所有其它参数之间呈正相关;但精液常规、精液生化和血清激素三者互不相关。从本组研究结果,作者提出了南京市正常男子这些指标的参考正常值。 相似文献
13.
Stefano Miceli Sopo Daniele Radzik Mauro Calvani 《Pediatric allergy and immunology》2007,18(7):575-582
Investigators have tried to identify a level of seric specific immunoglobulin E (IgE) that had a sufficient predictive value to diagnose a food allergy without having will resort to the food challenge. To search in literature, all the studies that have estimated the possibility to identify a level of seric specific cow milk IgE with a positive predictive value (PPV) of 95% for the first diagnosis of cow's milk allergy (CMA) in pediatric age. We have identified six studies, nearly all studies suffer from relevant methodological bias. Proposed cut-off are all different. The studied pediatric populations were highly selected. Also neglecting the methodological bias of the studies and the great difference of value between the proposed cut-off, it always remains to consider that the pre-test probability of having a CMA between the children enrolled in the six studies included in this review is particularly high. The likelihood ratio helps to transfer the results of a study on a diagnostic test just to our population, and it is more realistic rather than to entrust itself to the PPV or the negative predictive value, that are much influenced from the prevalence of the disease in the studied population. 相似文献
14.
AnAnalysisofChromosomeonSterilityCausedbyAzoospermiaorOligospermia¥WuMeiheng;TangWingnuo.(ACTAACADEMIAEMEDICINAENANJING,1995(... 相似文献
15.
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
18.
经过3年调查研究,最后初步确定长白山区治疗糖尿病的药用植物共有24科、37属、38种,为国内外专家研究长白山区的药用植物提供了第一手原始资料。 相似文献
19.
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
20.
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