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51.
目的:探讨用脉冲震荡法(Impulse Oscilbmetry IOS)测定呼吸阻力在支气管激发试验中的诊断价值。方法:对72例门诊及住院就诊有自觉症状,临床怀疑为支气管哮喘而不能确诊的患者进行支气管激发试验,用IOS测定5~35赫兹震荡频率时的粘性阻力(R5-R35),5赫兹时的周边弹性阻力(X5),共振频率(Fres),阻抗(Zre),与常规通气一秒量(FEV1),呼气峰流速值(PEF),1秒率(FEV1/FVC%)进行对比研究。结果:支气管激发试验阳性组患者FEV1比试验前FEV1基础值降低20%的同时呼吸阻力明显增加,且阻力增加较FEV1下降出现早,部分支气管激发试验通气功能阴性的患者而阻力增加。结论:脉冲震荡法为一种新型肺功能测定方法,用于支气管激发试验可大大减少以往常规通气测定中的不足,对支气管激发试验阴性的患者在鉴别诊断上增加了新的内容。  相似文献   
52.
Ⅱ型糖尿病血浆PAI-1、t-PA检测的意义和结果评价   总被引:1,自引:1,他引:0  
目的:通过对Ⅱ型糖尿病患者分组(伴血管病变组、胰岛素抵抗组、胰岛素抵抗伴血管病变组、Ⅱ型糖尿病组)检测PAI-1、t-PA抗原及活性,并计算抗原比和活性比,以评价各检测指标的临床价值。方法:采用ELISA法检测PAI-1及t-PA抗原,采用发色底物法检测PAl-1、t-PA活性。结果:189例标本总体患病组及分组后各组的PAI-1活性、t-PA活性及t-PA活性/PAI-1活性比值与正常对照组比较均有显著性差异(P<0.05)。患病组间除t-PA抗原,其余检测显示胰岛素抵抗组、胰岛素抵抗组伴血管病变组与Ⅱ型糖尿病组存在显著性差异(P<0.05)。结论:在上述检测指标中t-PA活性、PAI-1活性反映血管病变的发生较敏感,t PA/PAI-1的活性比值更具临床应用价值。  相似文献   
53.
Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·109 l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects.  相似文献   
54.
A vast number of potent neuropharmaceuticals, many of which are peptides, are excluded from entry into the brain because of the highly selective blood-brain barrier. The fact that a number of drugs have been shown to be transported directly to the central nervous system following application to the olfactory region of the nose is therefore of major interest. In the present study, the feasibility of delivering peptides to the brain via the olfactory route was assessed using insulin as a model peptide. Systemic hyperinsulinemia induced by subcutaneous injection did not significantly reduce the amount of 125I-insulin transported from the nose to the brain in vivo, which suggests that the impact of systemic absorption on drug transport is minimal. A linear relationship was seen between insulin accumulation in the brain and the dose applied, without any relevant saturation. Contrary to what was expected, both systemic and olfactory absorption of insulin was enhanced when the pH of the medium was near the isoelectric point. The amount absorbed to the brain was found to be linearly related to the net charge of the molecule (r = -0.61; n = 20). It was concluded that insulin gains access to the central nervous system from the olfactory region of the nose by a nonspecific pathway. The olfactory route may therefore become an important means to deliver peptides to the brain.  相似文献   
55.
We present our experience with twenty children with insulin dependent diabetes mellitus admitted during the past 2 1/2 years. Sixteen patients were admited with acute onset of ketoacidosis while four were having gradual onset. Active and symptomatic treatment was started in all diabetic ketoacidotic patients. One patient died during the acute stage. Eleven patients were followed for 3–6 months or more. Glycosylated hemoglobin was considered as a criteria for control. Three had good control, two fair and six poor control; six developed diabetic ketoacidosis and three developed hypoglycemia  相似文献   
56.
57.
目的 探讨血管内皮功能障碍对胰岛 β细胞分泌功能的影响。  方法 正常体重(NW )组 81例 ,单纯肥胖 (Ob)组 14 0例 ,肥胖伴高血糖 (Ob HG)组 97例。测定体质指数 (BMI)、腰臀围比 (WHR)、血压、血脂、空腹血糖和胰岛素 (FBG和FIns)及餐后血糖和胰岛素 (2hBG和 2hIns)。采用稳态模式法评价胰岛素抵抗 (HOMA IR)和 β细胞功能 (HOMA β)。用高分辨率血管外超声测定肱动脉对血流介导的内皮依赖性血管扩张 (EDD)及硝酸甘油的扩张反应。 结果 与Ob组比较 ,Ob HG组WHR、血压、甘油三酯 (TG)、FIns、2hIns和HOMA IR等显著升高 ,HOMA β明显降低 ,并伴有EDD所标志的血管内皮功能显著下降。相关分析显示 ,β细胞功能与EDD在Ob HG组呈显著正相关 (r=0 2 5 9,P <0 0 5 ) ,在Ob组和NW组无显著相关。在对Ob HG组影响EDD的因素进行控制后 ,EDD仍与 β细胞功能显著相关 (r =0 4 5 8,P <0 0 1)。多元逐步回归分析表明影响 β细胞功能的主要因素在Ob HG组为FBG、FIns和EDD ,在Ob组为FBG和HOMA IR。 结论 内皮依赖性舒张功能障碍可能是导致肥胖者 β细胞功能衰退 ,引发 2型糖尿病 (T2DM )的重要危险因素。  相似文献   
58.
目的:了解肺炎克雷伯菌肺炎的发病现状和对抗生素的耐药性及其治疗。方法:采用回顾性分析我院于2001年1月-2002年6月住院肺炎克雷伯杆菌肺炎50例的发病,对抗生素耐药性及其治疗。结果:患多见于中老年男性,临床表现以发热、咳嗽、咳痰多见。结果:肺炎克雷伯杆菌对抗生素具有多重耐药性,耐药率为氨苄西林100%,替卡西林96%,阿莫西林/棒酸54%,头孢西丁46%,庆大霉素44%,培福沙星42%,头孢他定38%,未发现对亚胺培南的耐药菌株。结论:肺炎克雷伯杆菌肺炎临床表现无特殊性,亚胺培南对肺炎克雷伯杆菌的耐药率最低,应作为治疗重症肺炎克雷伯杆菌肺炎首选用药。  相似文献   
59.
Immunohistochemistry using both a newly developed polyclonal, and a commercially available monoclonal, anti-insulin receptor antibody was done on the midbrain from cases of idiopathic Parkinson's disease (PD), Alzheimer's disease, amyotrophic lateral sclerosis, vascular parkinsonism and non-neurological controls. Both antibodies gave indentical patterns of neuronal staining. The neurons of the oculomotor nucleus were immunopositive in all the brains. However, the neurons in the pars compacta of the substantia nigra, paranigral nucleus, parabrachial pigmental nucleus, tegmental pedunculopontine nucleus, supratrocheal nucleus, cuneiform nucleus, subcuneiform nucleus and lemniscus medialis, which were positive in other diseases and in non-neurological controls, were not stained by these antibodies in PD brains. These results suggest that, in PD, a dysfunction of the insulin/insulin receptor system may precede death of the dopaminergic neurons.The work in the Kinsmen Laboratory was supported by the MRC of Canada and the Parkinson Society of Canada  相似文献   
60.
调查1988年3月~5月我院591例住院病例,发生96例次院内感染,总发病率16.2%。院内感染病原菌中,革蓝氏阴性杆菌占72.9%,革蓝氏阳性球菌占12.9%,念珠菌属占14.1%。院内感染病原菌的耐药性明显高于院外菌株。绿脓杆菌对庆大霉素和羧苄青霉素的耐药率分别为63.6%和54.5%。其它革蓝氏阴性杆菌院内株对常用抗生素如氨苄青霉素、羧苄青霉素、庆大霉素和妥布拉霉素的耐药率分别为82.5%、 67.5%、47.5%和45%。革蓝氏阳性球菌院内株的耐药性也很严重,表葡菌对多种半合成青霉素类、红霉素、复方新诺明甚至万古霉素的耐药率达60%以上。同时分离出耐甲氧西林金葡菌。  相似文献   
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