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91.
目的:进一步探索肺氧中毒的机理。方法:在大鼠常压高浓度氧(97%±2%)暴露的早期,观察肺血管紧张素转化酶(ACE)活性、脂质过氧化物(LPO)水平及肺泡毛细血管超微结构的变化。结果:随着肺ACE活性的下降和LPO水平的升高,部分肺泡内皮细胞(EC)出现胞浆水肿,同时肺泡毛细血管内白细胞、血小板明显增多。结论:肺泡EC胞膜功能的受损,尤其是胞膜结合的ACE活性下降所致对炎性介质清除的减少,可能起动了以肺泡EC胞膜通透性增高和炎细胞粘附为特征的早期肺氧中毒。  相似文献   
92.
The circulating concentration of 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] is a physiologic index of enzymatic activity of the renal 1-hydroxylase of 25-hydroxychole-calciferol (25-OH-D3). Hydroxylation of 25-OH-D3 and circulating 1,25-(OH)2D3 are decreased in the streptozotocin diabetic rat. We previously found that activity of another redox enzyme system, cytosolic superoxide dismutase, also decreased in streptozotocin diabetes, can be restored by treatment with glutathione. In the present experiment we tested the effect of glutathione treatment on vitamin D metabolism in control and diabetic rats. Enteral glutathione increased circulating 1,25-(OH)2D3 and decreased 25-OH-D3 in both control and diabetic animals. These results suggest that exogenous glutathione increases 25-OH-D3 1-hydroxylation both under basal conditions in the normal animal and in diabetes-induced depression.  相似文献   
93.
目的:观察ARB-valsartan及ACEI-benazeprilat能否抑制由AngⅡ、PDGF引起的SHR肾小球系膜细胞的增殖与肥大。且比较单用时作用孰强孰弱,联合应用后有无协同效应。方法;采用经典SHR系膜细胞培养技术,细胞中加入各种因子和(或)药物,以^3H-leucine或^3H-thymidine掺入后的cpm值反映蛋白或DNA合成。采用t test检验差异的显著性。结果:1、系膜细胞在AngⅡ、PDGF刺激后引起的增殖与肥大,均可被valsartan及benazeprilat抑制。2、比较发现单一用药在同一浓度下,valsartan较benazeprilat能更有效地抑制细胞的增殖与肥大。3、联合用药在同一浓度valsartan benazeprilat均比单用valsartan或benazeprilat效果明显。结论:1、valsartan与benazeprilat均能抑制SHR系膜细胞的增殖与肥大。2、valsartan在抗系膜细胞增殖与肥大作用稍强于benazeprilat。3、在一定浓度条件下联合用药对抗系膜细胞的增殖与肥大作用,较单一用药效果明显。  相似文献   
94.
本实验将赖型钩端螺旋体(简称钩体)DNA基因库的克隆pCX7制备成 ̄(32)P-重组DNA探针,对8个不同血清群的17株问号状钩体、双曲钩体PatocⅠ株以及细螺旋体3055株DNA进行打点杂交;同时用15种DNA片断进行限制性内切酶谱分析。结果表明,该重组DNA具有问号状钩体种(Species)特异性,但与不同问号状钩体之间的同源性程度有差别;限制性内切酶谱分析发现pCX7重组DNA片段长约1.7kb,具有1个Bg1Ⅱ识别位点和3个BstB1识别位点。  相似文献   
95.
目的评估伊那普利治疗糖尿病肾病(DN)的临床疗效 ,并探讨其作用机制。方法40例持续微量蛋白尿的非胰岛素依赖型糖尿病(NIDDM)患者随机分为常规治疗组(n=19)和伊那普利治疗组(n=21)。利用 131I -邻碘马尿酸钠测定有效肾血浆流量(ERPF) ;肾小球滤过率(GFR)以内生肌酐清除率表示 ;通过ELISA法测定尿微量蛋白 ,包括白蛋白(ALB)、转铁蛋白(TF)、视黄醇结合蛋白(RBP)和N -乙酰 - β氨基葡萄糖苷酶(NAG)。结果伊那普利治疗组增高的尿ALB、TF、RBP和NAG均显著下降 ;ERPF显著增加 ;增加的滤过分数(FF)显著减低。而常规治疗组这些参数无显著变化。结论伊那普利具有改善DN患者的肾小球血流动力学 ,保护肾小球和肾小管功能的作用  相似文献   
96.
目的 研究全麻诱导以及手术对肥胖患者血浆抵抗素 (resistin)和肾素、血管紧张素Ⅱ及血糖的影响。方法 选择 4 0例全麻手术患者 ,根据BMI指数分为两组 :A组 (BMI>2 5 ) 2 0例为肥胖者 ;B组 (2 1 相似文献   
97.
Sudden cardiac death (SCD) may occur in as many as 40% of all patients who suffer from heart failure. This review describes the scope of the problem, risk factors for SCD, the effect of medications used in heart failure on SCD and the potential effect of the implantable cardioverter-defibrillator in primary prevention.  相似文献   
98.
Two experiments were performed to investigate the relationship between the expression of sodium appetite and the appearance of Fos-like immunoreactivity (Fos-IR) in the brain of rats. In the first experiment, rats were depleted of sodium by treatment with furosemide 24 h prior to sacrifice and without access to either food or sodium solution. Some rats had access to distilled water, and others had no fluids available during the 24 h. All of the furosemide-treated rats showed Fos-IR in both the subfornical organ (SFO) and around the organum vasculosum laminae terminalis (OVLT). Rats with access to distilled water during the depletion period showed no Fos-IR in the supraoptic (SON) or paraventricular hypothalamic nuclei (PVN) and, in parallel behavioral studies, comparably-treated rats consumed only 0.3 M NaCl solution at the end of the 24 h. In rats that had no fluids during the deprivation period, only about one half showed Fos-IR in SON and PVN and, in parallel behavioral studies, comparably treated rats consumed both water and 0.3 M NaCI solution at the end of 24 h. In a second experiment, cerebroventricular administration of renin stimulated short latency intake of 0.3 M NaCI and water. The relative intakes of water and NaCl were comparable at a low dose of renin, but intake of water exceeded that of NaCl after higher doses. Renin induced Fos-IR in SFO, MnPO, peri-OVLT region, SON and PVN. Both Fos-IR and fluid intake were antagonized by administration of losartan, an angiotensin 11 type 1 receptor antagonist. Thus, only the circumventricular organs of the lamina terminalis showed Fos-IR during each natriorexigenic regimen in these studies. These data support the view that Ang 11 of both central and peripheral origin activates the SFO and/or peri-OVLT region and contributes to sodium appetite.  相似文献   
99.
1. The role of angiotensin as a modulator of proximal glomerulotubular (GT) balance was investigated in anaesthetized rats by examining the relationship between glomerular filtration rate (GFR) and absolute proximal reabsorption (APR) during removal of endogenous angiotensin II (AII) and III (AIII) with enalaprilat (CEI) and then during their subsequent replacement by intravenous infusions. 2. Enalaprilat lowered mean arterial blood pressure (MABP) and increased renal blood flow (RBF), GFR, urine flow rate and sodium excretion. Filtration fraction (FF) was not altered. Absolute proximal reabsorption, derived from fractional lithium clearance, increased by only 48% of the change expected for 'perfect' GT balance. 3. Angiotensin II replacement corrected MABP, GFR and plasma renin level, but reduced RBF and increased FF; APR was decreased and GT balance was restored. Urine flow and sodium excretion remained above control values with AII. 4. Replacement with AIII did not correct the hypotension but completely reversed the renal and renin responses to enalaprilat and restored GT balance without affecting FF. 5. It was concluded that the relation between proximal reabsorption and GFR is considerably modified by the intrarenal angiotensin concentration. The findings are best explained by a direct stimulation of proximal tubular sodium transport by angiotensin at the concentrations existing in anaesthetized rats.  相似文献   
100.
目的通过对32例窒息后心肌受累的新生儿治疗前后心肌酶谱测定,了解心肌酶谱在窒息新生儿心肌损害诊治中的意义。方法32例均自入院后12h及治疗后5~7天各静脉采血1次,作GOT、LDH、CK、CK-MB检查。结果窒息后心肌损害治疗前后心肌酶谱各项指标比较差异均有显著统计学意义(P〈0.01),出院时心肌酶多恢复正常。结论对窒息新生儿做心肌酶谱检查,有利于早期发现心肌损害并及时治疗,并可作为判断疗效及预后的指标。  相似文献   
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