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991.
ACUTE EFFECT OF ETHANOL ON RENAL ELECTROLYTE TRANSPORT IN THE RAT   总被引:1,自引:0,他引:1  
1. Despite human and animal studies, the direct effect of ethanol on renal water and electrolyte transport is poorly understood. The acute effect of increasing plasma concentrations of ethanol was evaluated in a water diuretic anaesthetized rat model which inhibits endogenous arginine vaso-pressin (AVP) release. 2. Ethanol at a plasma concentration of 1.69 ±0.28 mmol/L produced an immediate increase in urine flow (174 ± 11 μL/min pre-ethanol and 189 ± 13 and then 206 ± 12 μL/min during the ethanol infusion; P<0.001) as well as an increase in fractional sodium excretion (0.17 ± 0.04 to 0.28 ± 0.05 and 0.27 ± 0.05%; P<0.001). There was also a brief phosphaturia. These increases in electrolyte excretion had returned to control values by 20 min despite a further increase in the plasma ethanol concentration. 3. The urinary excretion of potassium, calcium and magnesium was not altered nor was glomerular filtration rate or renal plasma flow. 4. Ethanol at a mean concentration of 1.60 mmol/L did not alter the action of a maximal concentration of AVP (75 ng/kg) on water or electrolyte transport. However, the antidiuretic effect of a submaximal concentration of AVP (7.5 ng/kg) was augmented by ethanol at concentrations of 1.63 and 0.98 mmol/L. 5. These studies suggest that the ethanol induced diuresis commonly ascribed to inhibition of AVP secretion may also be due to other intrarenal effects of ethanol, possibly acting within the proximal tubule. These results also confirm recent in vitro findings that while ethanol does not inhibit the action of a maximal concentration of AVP, it does modulate the effects of lower AVP concentrations.  相似文献   
992.
冶金炼铁炉前工人职业性皮损调查研究关虹,王溪鸿,杨玉萍(辽宁省本溪钢铁公司劳动卫生研究所,117021)作者对炼铁炉前工人"熊猫眼"样皮损病因及特异部位皮损进行研究,为改善劳动条件,防治职业性皮肤病提供一些依据。以某炼铁厂5号炉前工人为观察组,以炼钢...  相似文献   
993.
本文综述本校传染病学教研室1955~1995年间所取得的科研成果。内容包括10余种传染病与寄生虫病的临床和基础研究,其中以华支睾吸虫病、恙虫病等有广东特色的传染病以及伤寒、痢疾、病毒性肝炎等影响人民健康最普遍的传染病为重点。反映了建国以来各个时期本教研室对防治这些传染病所作的贡献。所取得的成果,相当一部分通过多年来的验证,已获得广大传染病工作者所认同或列为常规,部分已获得部委级奖励。现在重温这些成果,可能起承前启后的意义。  相似文献   
994.
Thirty patients with metastatic breast carcinoma to the liver underwent systemic chemotherapy. Twentyfour of these patients also received hepatic arterial infusion chemotherapy, three in conjunction with hepatic artery embolization. The morphologic changes of the liver believed to be due to chemotoxic effect of treatment occurred in 27 patients, and were evaluated by serial computed tomography (CT) examinations. These included fatty changes in seven patients, severe cirrhotic changes in four, localized atrophy with regional contour changes in three, and areas of low density in the regions of previously treated metastases in 13. The CT features of cirrhosis included density changes along with nodular irregularity of the hepatic borders with marked decrease in liver size and development of ascites.  相似文献   
995.
李垚  吴坤  赵艳  于卫平 《中国公共卫生》2003,19(11):1290-1292
目的 探讨维生素E琥珀酸酯 (VES)诱导人胃腺癌SGC -790 1细胞凋亡的死亡受体 (Fas)信号转导途径。方法 人胃腺癌SGC -790 1细胞经不同剂量VES(5,10 ,2 0 μg/ml)处理 ,同时做琥珀酸、维生素E和空白对照 ,采用DAPI(4,6-贰脒基 -2 -苯基吲哚 )荧光染色法观察细胞凋亡情况 ,用WesternBlot法检测Fas、带有死亡结构域的Fas相关蛋白 (FADD)和天冬氨酸特异性半胱氨酸蛋白酶 (caspase -8)蛋白表达情况 ,Fas和FADD反义寡聚核苷分别转染SGC -790 1细胞后 ,用荧光法检测caspase -8活性。 结果 经VES处理后的细胞DAPI染色可见凋亡的形态学改变 ,2 0 μg/mlVES处理 48h后的细胞凋亡率为 89.6% ;VES处理 48h后Fas、FADD和caspase -8蛋白表达明显增加 ,且呈剂量 -效应关系 ;阻断Fas可明显抑制FADD蛋白表达 ,Fas和FADD反义寡聚核苷转染细胞后caspase -8活性明显降低 (P <0 .0 1) ,其中阻断Fas的效果高于阻断FADD。结论 维生素E琥珀酸酯诱导人胃腺癌SGC -790 1细胞凋亡过程中启动了Fas信号转导途径 ,VES启动Fas后 ,FADD将Fas和caspase -8联接起来 ,活化caspases级联反应 ,从而构成Fas/FADD/caspase -8的凋亡信号途径  相似文献   
996.
重组人生长激素对内毒素血症大鼠的治疗作用   总被引:1,自引:0,他引:1  
目的 :观察重组人生长激素 (rhGH)对大鼠内毒素血症的治疗效果。方法 :76只SD大鼠随机分为正常对照组、内毒素血症组 (仅腹腔注射鸵鸟株大肠杆菌 (1 5ml/kg ,1× 1 0 10 cfu/L)及治疗组 (腹腔注射鸵鸟株大肠杆菌后行rhGH肌肉注射 (2 2 5IU/kg/d)。内毒素血症组及治疗组又依观察时点再分为 1天、3天两个亚组。采用放射免疫分析方法测定血浆肿瘤坏死因子 α(TNF α)浓度并观测大鼠血压的变化。结果 :与正常对照组相比 ,无论是内毒素血症组还是治疗组 ,1天时其大鼠血浆TNF α浓度均明显升高 (P <0 .0 5 ) ;虽然两组大鼠血压都降低 (P <0 .0 5 ) ,但治疗组大鼠血压降低幅度明显小于内毒素血症组 (P <0 .0 0 1 )。 3天时 ,内毒素血症组大鼠血浆TNF α浓度降至正常对照水平 ,而治疗组大鼠血浆TNF α浓度却明显低于正常对照组 (P <0 .0 0 1 )及内毒素血症组 3天水平 (P <0 .0 5 )。结论 :rhGH能明显减轻内毒素血症大鼠血压的下降 ,对内毒素血症大鼠具有较理想的治疗效果 ;rhGH减轻血压下降的机制可能与其能抑制TNF的释放等有关  相似文献   
997.
将2例HBV_2患者血清HBsAg纯化,分析了HBV_2的HBsAg氨基酸组成,并与分子量为630198道尔顿HBV_1的HBsAg三种多肽氨基醚组成比较。实验发现,HBV_2与HBV_1的HBsAg的氨基醚组成有较大区别,且区别指数均在13以上。提示HBV_1和HBV_2的HBsAg在一级结构上存在较大差异;HBV_2可能系一新的乙型肝炎病毒,也可能系由于HBV_1S区核苷酸突变所致的变异株。  相似文献   
998.
The association of multiple liver cell adenomas containing foci of focal nodular hyperplasia with a spontaneous intrahepatic portohepatic venous shunt is reported in a 13-year-old male patient. At least eight nodules less than 10 cm in diameter were recognized and proved by means of surgical resection or surgical biopsies. These lesions were heterogeneous and hypodense on precontrast computed tomographic (CT) scans, and were slightly enhanced after injection of contrast medium. At magnetic resonance (MR) imaging, the signal intensity of these nodules varied. It was either hyperintense or hypointense on T1-weighted SE images. Sonography and angiography demonstrated a portohepatic venous shunt and hepatic arterialization was observed. These findings emphasize the hypothesis that hepatic arterialization may cause the development of liver cell adenomas. Moreover, it is suggested that liver cell adenoma and focal nodular hyperplasia have a common pathogenesis.  相似文献   
999.
The effects of dextropropoxyphene on the steady-state kinetics of oxcarbazepine and its metabolites were investigated in eight patients with epilepsy or trigeminal neuralgia. One patient dropped out of the study, presumably due to side-effects of dextropropoxyphene. Dextropropoxyphene did not affect the plasma levels of the principal active metabolite, 10,11-dihydro-10-hydroxy-carbamazepine. Since dextropropoxyphene is known to increase the plasma levels of carbamazepine, leading to toxicity, the findings of this study suggest that oxcarbazepine is a useful alternative to carbamazepine when concomitant dextropropoxyphene therapy is required.  相似文献   
1000.
Since peripheral odontogenic fibroma (POF) is characteristically described as a solitary lesion and no diffuse POF had been reported in the literature, our cases should be considered as extremely unusual. Three diffuse cases of POF are described of which one case was seen in association with ocular and skin lesions. The question arises whether POF should be considered as a true odontogenic tumor rather than a diffuse hamartomatous lesion caused by uncontrolled induction of the gingiva. It is also possible that such lesions could be part of a yet undescribed syndrome.  相似文献   
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