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181.
用放射免疫分析测定75例肾病患者血清和尿液含铜锌离子超氧化物歧化酶(Cu-Zn-Superoxidedismutase,简称Cu-Zn-SOD或SOD-1)的含量,并与51名健康人对比。结果显示,慢性肾功能不全(CRF)血透组患者血清SOD-1含量显著增高(P<0.01),随着血液透析期的延长,其含量有渐升趋势;非血透组略有降低(P>0.05;其它肾病组明显降低(P<0.01)。三组患者尿液SOD-1含量呈不同程度增高(P均<0.01),并随着病变的严重程度而增幅更明显,血/尿SOD-1比值也随之降低。本文初步分析了这些变化的原因及意义。 相似文献
182.
异搏定对失血性休克犬肾脏的保护作用及其机制的研究 总被引:2,自引:0,他引:2
复制犬失血性休克模型。动物随机分为两组:失血对照组(n=5),失血+异搏定组(n=6)。结果发现,异搏定治疗后肾脏组织内黄嘌呤氧化酶活性和丙二醛含量均较失血对照组明显降低,而锰-超氧化物歧化酶活性却显著高于失血对照组,肾脏组织电镜观察显示其超微结构损伤也较失血对照组轻。提示钙拮抗剂异搏定治疗失血性休克可以减轻肾脏损伤,其机理与改善内脏灌流,减少氧自由基生成有关。 相似文献
183.
目的:研究和探索胚胎小鼠肝脏细胞的横向分化潜能。方法:将2×103 C57BL/6j雄性胚胎小鼠的肝脏Sca-1+细胞从尾静脉注射到受致死性γ射线(10 Gy, 60Co)全身照射的同种成年雌性小鼠体内;于移植后2个月, 用荧光原位杂交和免疫组织化学技术, 检测雄性胚胎小鼠肝脏Sca-1+细胞在雌性受体小鼠肾脏和脑组织内的分化情况。结果:在雌性受体小鼠的肾脏和脑组织内, 分别检测到Y染色体阳性的供体来源的肾小管上皮组织细胞样和神经组织细胞样的细胞, 其细胞表型分别为RCA+/CD-45F-4/80和NueN+/CD-45F-4/80。结论:胚胎小鼠肝脏Sca-1+细胞具有向肾脏和脑组织细胞横向分化的能力。 相似文献
184.
Cyclosporine A-induced kidney alterations are limited by melatonin in rats: an electron microscope study 总被引:1,自引:0,他引:1
The effect of melatonin on experimental prolonged cyclosporine A (CsA) nephrotoxicity was analyzed by electron microscopy and morphometry. Twenty female Wistar rats were divided into groups that received (1) CsA at a therapeutic dose (15 mg/kg/day) sc for 40 days; (2) olive oil, CsA vehicle, as controls; (3) CsA plus melaton (1 mg/kg) ip for the same time; (4) melatonin alone, as additional controls. All controls had normal renal ultrastructure. However, in CsA group, both tubular and glomerular alterations were observed. The authors found apoptotic and necrotic proximal tubules with disrupted brush border, swollen mitochondria, abundant lysosomes; in the glomerulus, amorphous basement membrane, and abnormal mesangial matrix. CsA plus melatonin administration partly prevented these changes. Nevertheless, fibrillar deposits in podocytes and basolateral membrane dilatations in proximal tubules were observed. Histopathological analysis on semithin sections and ultrastructural morphometry were also performed. CsA induced interstitial fibrosis, atrophy, and PAS positive inclusions in the proximal tubules. Moreover, CsA reduced glomerular and mesangial volume but enhanced mesangial matrix volume and basement membrane thickness. After CsA plus melatonin, these parameters were reduced in the proximal tubules and restored in the glomerulus. In conclusion, melatonin attenuated morpho-quantitative alterations induced by CsA in the rat kidney. 相似文献
185.
特殊染色和免疫组织化学染色在肾上皮性肿瘤诊断中的应用 总被引:2,自引:1,他引:2
目的 探讨肾上皮性肿瘤的诊断及鉴别诊断。方法 对91例具有较完整病理资料的肾上皮性肿瘤进行了常规组织学观察,Mowy胶状铁染色及CD10、细胞角蛋白(CK)7、波形蛋白免疫组织化学染色。结果 91例肾上皮性肿瘤中肾透明细胞癌78例,占86%;肾乳头状癌8例,占9%;肾嫌色细胞癌4例,占4%;肾嗜酸细胞腺瘤1例,占1%。78例肾透明细胞癌中CD10、波形蛋白阳性分别为63例(81%)和69例(88%),主要表现为细胞膜阳性。74/78肾透明细胞癌CK7呈阴性,17/17 Mowy胶状铁染色阴性或呈灶状粗颗粒。肾嫌色细胞癌4例,CK7均呈胞膜阳性;Mowy胶状铁染色表现为胞质内蓝色细网状;4例CD10肿瘤细胞膜均阴性,波形蛋白阴性。肾嗜酸细胞腺癌1例CD10,CK7,波形蛋白,Mowy胶状铁染色均为阴性或不特异。结论 在常规诊断肾上皮性肿瘤有困难时免疫组织化学CD10,CK7,波形蛋白染色以及Mowy胶状铁染色对鉴别诊断有帮助。 相似文献
186.
B. D. Slaughter H. S. Osiecki R. B. Cross 《Pflügers Archiv : European journal of physiology》1976,362(3):203-208
Summary Renal reabsorption of bicarbonate was studied in Merino ewes during carbonic anhydrase inhibition. Bicarbonate reabsorption was directly proportional to plasma bicarbonate concentration. No tubular maximum for bicarbonate was demonstrated. Elevation of arterialPCO2 or depression of arterial pH caused slight increases in bicarbonate reabsorption. The data suggest that bicarbonate is reabsorbed by 2 distinct processes. The quantitatively more significant process may involve ionic reabsorption of bicarbonate secondary to Na+ reabsorption and a relatively minor part of bicarbonate reabsorption may be secondary to H+ secretion. 相似文献
187.
《Human immunology》2022,83(3):219-224
To date, traditional pre-transplant risk factors have failed to provide accurate risk stratification in transplantation. As a result, the practice of precision medicine remains elusive, resulting in a one-size-fits-all therapeutic approach for most patients. However, recent advancements in the understanding of HLA molecules at the molecular level have revitalized interest in HLA mismatch assessment. This review discusses HLA molecular mismatch as a potential prognostic and predictive biomarker available at the time of transplantation and answers some of the common questions and critiques of this approach. We highlight the retrospective data that supports single molecule risk categorization and explore the next steps required to evaluate its potential in clinical practice. 相似文献
188.
M. Cikrt J. Hurych D. Kuklová J. Havrdová P. Lepší J. Kopecký B. Milek A. Nauš 《International archives of occupational and environmental health》1985,55(3):241-246
Summary In a 61-year-old woman, who had been exposed for 20 years to cadmium in the production of Ni-Cd batteries, nephrectomy of the contracted kidney was performed. The removed kidney was examined histologically and the cadmium concentration was determined in the cortex (44.97 g g–1) and in the medulla (7.71 g g–1). The homogenates of the renal cortex and medulla were subjected to gel filtration on Sephadex G-75. In the cortex, as well as the medulla, cadmium was predominantly found in the low-molecular (metallothionein) fraction, but in the cortex, Cd content in this fraction was six times higher than in the medulla. The determination of SH groups and proteins in high- and low-molecular fractions indicates an induction of the metallothionein formation primarily in the renal cortex. 相似文献
189.
Rats fed a basal, low-selenium diet, or this diet supplemented with 0.1 ppm and 1.0 ppm selenium and treated with cadmium, showed significant reductions in the activity of the selenoenzyme glutathione peroxidase in kidney and liver. Cadmium treatment resulted in a significant increase in the activity of selenium-independent glutathione peroxidase activity in the liver of selenium-supplemented rats. Selenium-independent glutathion peroxidase activity was significantly reduced in the kidney of rats fed the basal low-selenium diet. There was no significant increase in lipid peroxidation in any of the groups studied. Cadmium concentrations in the kidney and liver of these animals ranged from about 250 to 700 g Cd/g tissue, dry weight.Supported by NIEHS Center Grant ES-00159 and a Grant from the Selenium-Tellurium Development Association 相似文献
190.
M. Martea Y. A. Hekster T. B. Vree A. J. Voets J. H. M. Berden 《Pharmacy World & Science》1987,9(2):110-116
Cefradine and co-trimoxazole pharmacokinetics were studied in a patient with peritonitis that complicated continuous ambulatory peritoneal dialysis (CAPD). Concentrations in the plasma reached after oral administration of 500 mg cefradine four times daily and 400/80 mg co-trimoxazole four times daily were for cefradine 100g/ml, for trimethoprim 15g/ml, and for sulfamethoxazole 100/ml, respectively. In the dialysate concentrations were reached of 35–70/ml cefradine, 2–5/ml trimethoprim and 8–17g/ml sulfamethoxazole. The values for sulfamethoxazole are regarded too low to be clinically effective. Half-lives protein binding values and CAPD clearances are presented. Low CAPD clearances were obtained during the night and high values during the day. The dosage yielded too high plasma trimethoprim concentrations, while sulfamethoxazole dialysate concentrations were too low. It seems questionable therefore whether co-trimoxazole can be used orally for the treatment of CAPD peritonitis. 相似文献