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91.
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   
92.
本文报告50名正常人及73例消化系疾病患者血清游离氨基酸检测结果。使用氨基酸自动分析仪,对血中40余种氨基酸组分进行定性定量测定。肝硬化病人芳香氨基酸显著升高,支/芳分子比值明显低于正常值(P<0.01),甲硫氨酸、色氨酸均升高.肝脓疡.消化道肿瘤患者也有此种变化(P<0.05)。统计21种组分中,各病理组有10多种组分有非常显著差异(P<0.01)。结果提示:血液氨基酸测定可为某些消化系疾患,尤其是肝病的诊治提供较好指标。本文改进自动分析条件,节省时间。节约试剂。  相似文献   
93.
Abstract: The plasma ratio of each neutral amino acid (tryptophan (TRP), tyrosine (TYR), valine, isoleucine, leucine (LEU) or phenylalanine) to the sum of the other neutral amino acids was measured in 16 : manic and 14 : depressed patients. In the manics, there was a correlation between the psychomotor activity and the plasma TRP and LEU ratios. In the depressives, the depressed mood, retardation and global severity were correlated with the TRP ratio. The zotepine responders showed an increase in the TRP ratio after treatment. In the mianserin responders, the TYR ratio, which was high before the treatment, decreased to the normal range after the treatment. But, the plasma amino acid ratios remained unchanged in the patients treated with lithium carbonate or amitriptyhe. These results suggest that, in manic-depressive illness, there might be abnormalities in the metabolism of neutral amino acids, mainly of TRP and TYR, and that the plasma TRP and TYR ratios might be important indicators for determining the efflcacy of some drugs.  相似文献   
94.
吉林省经七年来的鼠情监测,基本查清与人们接触密切的鼠类,特别是传播疾病的主要鼠类的分布规律,分析出我省家鼠有两个高峰(6月和10~11月),野鼠也有两个高峰(6月和10月),这与我省流行性出血热两个高峰相吻合,鼠峰在病峰之前。1986年以后,由于我省开展大规模灭家鼠活动,家鼠高峰已不存在规律性。通过几年来的灭鼠活动,使家鼠密度呈下降趋势,城镇褐家鼠和小家鼠构成比发生变化。城镇未爆发家鼠型流行性出血热。鼠情监测为灭鼠防病工作提供了科学依据。  相似文献   
95.
To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty.  相似文献   
96.
The post-mortem diagnosis of acute myocardial ischaemia may be difficult to establish in the absence of morphological changes in the myocardium or recent coronary thrombosis. Ischaemic cell injury leads to potassium (K) efflux and sodium (Na) influx and, if the blood is still circulating, the K:Na ratio of the tissue falls. In this study, the K:Na ratio was measured by eluting the ions from samples of myocardium and assaying the eluate. The method yields similar results to those obtained by a previous method, in which myocardial samples were homogenized. The K:Na ratios on samples of horizontal slices through the heart were plotted on maps of the slices. A low K:Na ratio corresponded to, but extended beyond, areas where there was morphological evidence of ischaemia. The method is simple and may be of use in routine practice.  相似文献   
97.
Death certificates from 23,890 male and female non-Hodgkin's lymphoma (NHL) cases and 119,450 noncancer controls from 24 states for the period 1984-1989 were used to generate hypotheses regarding occupational associations. Cases were frequency matched by age, race, and gender with five controls per case. Odds ratios were calculated for 231 industries and 509 occupations. Significant associations were observed for a variety of white-collar professionals (i.e., real estate agents, secretaries, bookkeepers, teachers, postal employees, business agents, engineers, chemists, and medical professionals) and blue-collar occupations (i.e., firefighters, farm managers, aircraft mechanics, electronic repairers, mining machine operators, and crane and tower operators). © 1995 Wiley-Liss, Inc.  相似文献   
98.
对广西武鸣华侨农场4158人进行基线普查,410人进行膳食调查和作8小时夜尿电解质测定,并将高血压低发区广西的资料与高发区的北京作对比.结果显示,体重指数高是高血压一个重要的危险因素,而体重过重又与膳食中摄入碳水化合物和总热量大有关.另一主要的危险因素是钠,膳食中摄入钠高,尿Na和Na/K比值高者,血压水平和高血压的患病率亦高.  相似文献   
99.
目的提高静脉穿刺成功率,减少患儿因反复穿刺造成的痛苦及恐惧,减轻家长因担心穿刺困难而产生的焦虑,提高治疗和抢救的效率。方法详细介绍了QQC活动在提高儿科静脉穿刺成功率的应用,包括找出目前存在的问题,确定目标、采用流程图的方法分析问题存在的原因,制定相应的质量改进方案,并测量实施结果。结果实施QQC活动后静脉穿刺成功率比实施前明显提高。结论有效的QQC活动可以提高静脉穿刺成功率。  相似文献   
100.
The diuretic and the antihypertensive actions of torasemide were examined in renal and genetic hypertensive rats and compared to the effects of furosemide. Oral administration of torasemide (1 and 3 mg/kg) elicited a dose-dependent increase in the excretion of urine and electrolytes and elevated the urinary Na/K ratio in both renal and genetic hypertensive rats. Torasemide and furosemide had a similar maximum diuretic effect in the normotensive Wistar rat and the spontaneously hypertensive rat (SHR). However, the diuretic activity of furosemide was weaker in the renal hypertensive rat (RHR). Torasemide showed approximately 30 times greater diuretic potency than furosemide. Torasemide and furosemide demonstrated hypotensive action in hypertensive rat models, but not in the normotensive Wistar rat. Especially in the RHR, torasemide exhibited a more potent hypotensive action than furosemide. These results show that the diuretic and antihypertensive activities of torasemide are effective in various rat models of hypertension, while the diuretic activity of furosemide is weak in certain hypertensive rat models. © 1992 Wiley-Liss, Inc.  相似文献   
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