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71.
血清亚硝酸盐的快速测定 总被引:1,自引:1,他引:0
目的:建立一种无需去蛋白的血清亚硝酸盐的快速测定方法。方法:加入蛋白活化剂后,直接用Gries试剂显色分光光度测定。结果:方法的检测下限为0.2μmol/L,相对标准差为5.13%~8.86%,回收率为94.5%~99.8%(平均为97.8%)。血清NO-2浓度为14.38±0.25μmol/L时,批内变异系数为1.75%,NO-2浓度为5.69±0.25μmol/L时,批间变异系数为4.46%。测定55例正常人血清,得到血清中NO-2浓度的平均值分别为5.36±2.16umol/L;对糖尿病病人血清测定结果表明,亚硝酸盐浓度明显高于正常人。与去蛋白的Gries试剂分光光度法比较,结果无统计学差异。结论:用蛋白活化剂替代蛋白沉淀剂,减少操作步骤和干扰,测定准确、简便、快速,适用于血清中NO-2的测定。 相似文献
72.
急性有机磷中毒患者的血钾变化及临床意义的探讨 总被引:1,自引:0,他引:1
目的:探讨急性有机磷中毒患的血清钾变化及其临床意义。方法:对68例发病6小时内的急性有机磷中毒的患入院后测定血清钾,并根据不同的中毒程度、中毒方式、发病时间分组在比较,并设正常对照组对照。结果:中毒各组均有明显的低钾血症,与对照组比较均有显性意义(P<0.01),且重度中毒组与中、轻度组比较亦有显性意义(P>0.05),但两种不同的中毒途径与不同的中毒时间的组间血清钾的比较无显性意义(P>0.05)。结论:急性有机磷中毒可致明显的低钾血症,中毒越重,低钾血症越明显。在发病早期应注意监测血清钾的变化,及时纠正低血钾,预防或减轻中毒后严重合并症的产生。 相似文献
73.
常见阴离子对血清氯离子选择性电极法测定的影响 总被引:1,自引:0,他引:1
目的:研究离子选择性电极在测定血清氯时的影响因素。方法:用E-555电解质分析仪测定氟化钠、溴化钠、碳酸氢钠、硫氰化钾、碘化钾、铁氰化钾、硫化钠以及叠氮钠溶液,并将溴化钠、硫氰化钾、碘化钾、铁氰化钾、硫化钠、叠氮钠分别加入Cl~-均值为100mmol/L的混合血清中观察其具体的干扰情况。结果:所测8种物质中氟化钠、碳酸氢钠的影响较小,而溴化钠、铁氰化钾、碘化钾、铁氰化钾、硫化钠、叠氮钠的影响较大。结论:溴离子、碘离子、硫离子、氢氰根离子、叠氮钠对离子选择性电极法影响性较大,我们在工作中应加以重视。 相似文献
74.
Special Pharmacokinetic Considerations in Children 总被引:4,自引:2,他引:2
W. Edwin Dodson 《Epilepsia》1987,28(S1):S56-S69
Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection. 相似文献
75.
The pathogenesis of diabetic neuropathy is incompletely understood. The possibility that humoral neurotoxic factors contribute as a cause of diabetic neuropathy was tested by application of serum from patients with Type 1 and Type 2 diabetes to mouse neuroblastoma cells, which have the characteristics of adrenergic neurons in culture. Serum from patients with Type 1 diabetes and somatic neuropathy significantly inhibited both proliferation and differentiation of neuroblastoma cells, while serum from patients with Type 1 diabetes but no symptoms of neuropathy and patients with Type 2 diabetes and neuropathy had no effect on proliferation, and serum from Type 2 patients only marginally inhibited differentiation. The effects of Type 1 diabetic serum could be reversed by pre-absorption of the serum to neuroblastoma cells, and were independent of glucose levels. Immunoglobulins precipitated from the sera mimicked the effects of whole sera. These results suggest that Type 1 diabetes mellitus causes a change in serum composition, possibly related to autoimmunity, that is capable of contributing to adrenergic autonomic neuropathy in diabetic patients. 相似文献
76.
Katrina D. Ramsell Bai-Ge Zhao Daniel Baker Peter Cobbett 《Brain research bulletin》1996,39(2):109-114
The effects of serum on the morphological plasticity exhibited by pituicytes in explant cultures of the neurohypophysis of adult rats have been examined. Cultured pituicytes are normally nonstellate, protoplasmic, amorphous cells (< 25% are stellate with a distinct cell body and phase bright processes). After incubation (90 min) of pituicyte cultures in a HEPES buffered salt solution (HBSS) supplemented with isoproterenol or forskolin, the fraction of stellate pituicytes significantly increased. The increase in the fraction of stellate cells induced by isoproterenol was not reversed by subsequent incubation in isoproterenol-free HBSS for 90 min. In contrast, after stellation was induced in cultures by exposure to forskolin (90 min), the fraction of stellate cells was significantly reduced if these cultures were incubated in forskolin-free, serum (0.5%) supplemented HBSS for the same duration. Serum also blocked the increase in the fraction of stellate pituicytes induced by forskolin. These experiments suggest that serum components may have a significant role in controlling the plasticity of neuroglial relations in the neurohypophysis priviously demonstrated in vivo. 相似文献
77.
Taking as its point of departure the medicalization thesis and its limitations, this paper provides a critical discussion of certain more recent theoretical perspectives on life in contemporary society, and their relevance for understanding the relationship between modern medicine and the lay populace. In particular, attention is paid to the contours and existential parameters of life in ‘late’ modernity in terms of the following four key themes: (i) modernity as a ‘reflexive’ social order; (ii) ‘risk’ and the dialectic of scientific and social rationality; (iii) the ‘mediation’ of contemporary experience; and (iv) lay ‘re-skilling’ and the ‘life political’ agenda. On the basis of this, it is argued that far from being simply passive and dependent, a ‘critical distance’ is beginning to emerge between modern medicine and the lay populace; a situation which resonates with broader social trends and currents within society at large. 相似文献
78.
冠心病中血糖与血清微量元素间的关系分析 总被引:1,自引:0,他引:1
对75例冠心病患者依血糖水平分两组,进行12种血清微量元素测定,旨在探讨微量元素与冠心病及糖尿病间的相互关系。结果发现锌、铬、锰、硒、钴元素高血糖组较对照组血清水平为低,呈非常显著差异(P<0.0l);铜、镍元素增高,差异显著(P<0.05);而锶、铁、砷、铅、铝元素两组间无显著差异(P>0.1)。表明部分微量元素与冠心病及血糖间存在着密切联系。 相似文献
79.
80.
探讨香萱解郁方含药血清对血清剥夺致小鼠海马神经元HT22细胞损伤模型的影响。方法 采用血清剥夺培养HT22细胞建立神经损伤体外模型,实验分为对照组、模型组和中药组[中药组A(含药血清15%浓度)、中药组B(含药血清20%浓度)],各组血清剥夺12 h后,通过CCK8法检测各组细胞活力,确定15%浓度含药血清干预后细胞的存活率最高,设定为后续实验中药组的药物浓度。免疫荧光染色法检测神经元特异性微管蛋白(β-Tubulin Ⅲ)在各组中的表达,蛋白质免疫印迹法及qPCR法检测脑源性神经营养因子(BDNF)蛋白及其mRNA在各组中的表达。结果 在加药后培养12 h,中药组的细胞活力明显高于对照组与模型组(P<0.001)。培养24 h,模型组细胞活力较对照组明显下降(P<0.001),中药组较模型组明显提高(P<0.001)。培养36 h,模型组细胞活力较对照组显著下降(P<0.001),中药组较模型组明显提高(P<0.001)。模型组BDNF蛋白含量及 BDNF mRNA表达量较对照组显著降低(P<0.05,P<0.001),模型组少数神经元长出突起;中药组BDNF蛋白含量及BDNF mRNA表达量较模型组显著增加(P<0.05),中药组HT22细胞轴突突起长度和分支增加,β-Tubulin Ⅲ阳性表达明显增多。结论 香萱解郁方含药血清对血清剥夺诱导小鼠海马神经元HT22细胞损伤具有神经保护作用,可能与促进BDNF蛋白表达有关 相似文献