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991.
Ming Li Allison Martin Cheng Wen Steven W. Turner Lynley K. Lewis Judith A. Whitworth 《Clinical and experimental pharmacology & physiology》1995,22(12):919-923
1. We tested the ability of ouabain to cause chronic hyper tension by continuously infusing ouabain for 28 days (mini-osmotic pump implantation; i.p.). The blood pressure and metabolic effects of sham (150 mmol/L NaCI; n= 12) or ouabain infusion (10 μg/kg per day; n= 14; 100 μg/kg per day; n = 14) were examined in conscious Sprague-Dawley rats. 2. Plasma ouabain concentrations measured after 28 days of ouabain infusion were as follows: sham, not detectable (n= 11); ouabain 10 μg/kg per day, 0.60 ± 0.07 nmol/L (n= 14); and ouabain 100 μg/kg per day, 7.17 ± 0.57 nmol/L (n= 14; P < 0.001). 3. Sham or ouabain infusion did not alter food intake, bodyweight, water intake or urine output in conscious rats. 4. Blood pressure was not altered by sham treatment. Ouabain at 10 μg/kg per day or 100 μg/kg per day did not produce consistent rises in blood pressure. Ouabain at 10 μg/kg per day increased blood pressure on treatment day 12 only (+ 6mmHg; P < 0.05), while at 100μg/kg per day blood pres sure increased on treatment days 16 (+ 9 mmHg; P < 0.05) and day 18 (+ 8mmHg; P < 0.05) only. There was no significant difference in blood pressure between sham and ouabain groups. 5. Renal blood flow was decreased in rats infused with ouabain at 10 μg/kg per day (2.0 ± 0.3 mL/min per 100 g body-weight; n= 5; P < 0.01) and 100 μg/kg per day (2.2 ± 0.4 mL/ min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (3.5 ± 0.2 mL/min per 100 g bodyweight; n= 6). Renal vascular resistance was increased in rats treated with ouabain at 10 μg/kg per day (65.5 ± 12.6 mmHg/mL per min per 100 g bodyweight; n= 5; P < 0.01) and 100 μg/kg per day (66.0 ± 15.6 mmHg/mL per min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (32.6 ± 2.5 mmHg/mL per min per 100 g bodyweight; n= 6). 6. High plasma concentrations of ouabain do not cause consistent increases in blood pressure in conscious Sprague-Dawley rats. 相似文献
992.
Twenty-seven cases of metastatic tumor of posterior fossa were presented in this paper. Of the patients, 20 were males and 7 females; their age ranged from 20 to 68, and 89% of them were over 40 years of age. The primary foci found were bronchopulmonary carcinomas (7 cases), rhinopharyngeal carcinomas (3 cases), and cancer of the liver (1 case), but in 16 cases the primary foci were not found. All of these patients presented symptoms and signs of obviously increased intracranial pressure, and most of them had the signs of cerebellar and cranial nerves' lesions. Ventriculorgraphy and brain CT scanning were important procedures in the diagnosis, and MRI was most valuable in establishing the diagnosis and localization of posterior fossa metastatic tumors. Twenty-six patients underwent operation. The short-term follow-up study showed an improvement in 25 cases. There was one death. The surgical treatment of posterior fossa metastatic tumor was emphasized. Radiotherapy and chemotherapy were discussed. 相似文献
993.
To study whether HCV infection is present in dialysis patients and the status of antibody responses to HCV viremia, 16 patients undergoing hemodialysis were assayed for anti-HCV by ELISA and RIBA. A high incidence of anti-HCV (13/16) was found. All the 16 patients were studied for HCV viremia by 'nested' PCR and 10 were HCV RNA positive. Altogether 14 were anti-HCV and/or HCV RNA positive, which indicates that the incidence of HCV infection is high in hemodialysis patients, at least in some units. Cloning, sequencing of the PCR products showed high homology among isolates, with 91% homology to that of Japanese strains. It is important to study anti-HCV/HCV RNA in dialysis patients. 相似文献
994.
以液体稀释法比较了自制与进口十六烷基吡啶作用于4种口腔常见微生物的最低抑菌浓度和最低杀菌浓度的实验结果,经t检验证明两者间无显著差异,提示自制氯化十六烷基吡啶的药效质量可靠。并就控制接种菌量及杀菌机理等问题作了初步探讨。 相似文献
995.
996.
甘草甜素和甘草酸单铵促进IL-2增强NK活性的研究 总被引:1,自引:0,他引:1
本实验采用乳酸脱氢酶释放法研究甘草甜素和甘草酸单铵对人外周血NK细胞活性的影响。结果表明,甘草甜素和甘草酸单铵本身无增强NK细胞活性的作用,但可明显促进IL-2增强NK活性,这种增强作用与甘草甜素和甘草酸单铵的浓度有关。 相似文献
997.
998.
999.
对氰基苯代二氢哒嗪酮的设计,合成及抗惊活性的研究 总被引:1,自引:0,他引:1
在CoMFA3D-QSAR研究的基础上设计并合成了对氰基苯代二氢哒嗪酮。对溴苯甲醛与吗啉、氰化钾反应得α-p-溴苯基-4-吗啉基乙腈,再与丙烯腈反应得3-(p-溴代苯基)丙酸。对溴基被氰基取代后与肼反应得目标化合物。其抗惊活性属中等强度,与CoMFA方法预计值相差较大。 相似文献
1000.
对30侧成人颊脂体的形态,位置和血液供应进行了观测。颊脂体血供为多源性,主要血管蒂为上颌动脉的颊动脉和面动脉的颊支。依据上述血管蒂的解剖学走向和分布,颊脂体转位可修复邻近的颌面部和口腔软组织缺损。 相似文献