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81.
本工作观察了乙酰胆硷(Ach)和电刺激迷走神经对0.6N HCl引起的胃粘膜出血性损伤的保护作用,发现皮下注射50μg/kg的氯化Ach和电刺激膈下迷走神经5min,可明显降低HCl引起的胃粘膜出血量,这一作用可被消炎痛及阿托品所阻断。提示这种保护作用是通过依赖于M-受体的内源性前列腺素。 相似文献
82.
补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响 总被引:4,自引:0,他引:4
观察补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响。用SD雌性大鼠幼仔,出生9d龄注射丙酸睾丸酮,制成雄激素致不孕大鼠(ASR)模型。80d龄灌服补肾中药水溶液两周。100d龄心脏灌注处死。以核仁组成区蛋白嗜银染色(AgNOR)和增殖细胞核杭原(PcNA)为指标,观察卵巢颗粒细胞、间质腺细胞的形态学变化。结果:补肾中药能够使ASR卵巢颗粒细胞增殖、卵泡发育。治疗组的AgNOR和PcNA计数明显高于模型组,而与对照组之间无显著差异。结论:补肾中药的这种作用可能是通过调节了下丘脑-垂体-卵巢性腺功能的结果,从而促使卵巢颗粒细胞发育、卵泡成熟。 相似文献
83.
Gail Pairitz Jarvik Terri H. Beaty Paul R. Gallagher Paul M. Coates Jean A. Cortner 《Genetic epidemiology》1993,10(4):257-270
A sample enriched for familial combined hyperlipidemia (FCHL) was examined for evidence of an association between genotype at an apolipoprotein B (apoB) elevating locus defined by complex segregation analysis and FCHL. Complex segregation analysis detected a locus with a large effect on plasma apoB levels and was used to compute the most probable genotype of family members. None of the 35 normolipidemic adults carried a copy of the allele associated with elevated apoB levels, yet 58% of the 109 adults with FCHL carried 1 (29%) or 2 (28%) copies. Two of 28 (7%) normal children had 1 copy of this allele and none had 2 copies, while 88 of 182 (48%) children with FCHL had 1 (26%) or 2 (22%) copies. Further, 4l of 48 (85%) individuals classified as having hyperapobetalipoproteinemia did not carry a copy of this “elevated apoB” allele. Therefore, the presence of the allele associated with elevation of apoB level is highly predictive of FCHL and this association cannot be explained solely by the presence of elevated apoB levels in FCHL, suggesting that the locus controlling apoB levels may play an etiologic role in FCHL. © 1993 Wiley-Liss, Inc. 相似文献
84.
M. R. Wang C. Y. Chai J. S. Kuof 《Clinical and experimental pharmacology & physiology》1994,21(1):21-29
1. In chloralose-urethane anaesthetized cats, the dorsal cardiovascular reactive area (DCRA) in the parvocellular reticular nucleus dorsomedial to the facial nucleus, and the ventral cardiovascular reactive area (VCRA) ventromedial to the facial nucleus, were stimulated by microinjections of sodium glutamate (100–200 nmol) or electric current. 2. Stimulation of DCRA, with a long latency of 15–20 s, elicited a marked increase of blood flow in the contralateral femoral artery with little change to moderate increase in systemic arterial blood pressure (ABP). In the relatively dorsal portion of DCRA, however, a smaller increase of blood flow in the ipsilateral femoral artery was elicited. 3. On the other hand, stimulation of VCRA with a short latency (3–5 s) evoked an increase of blood flow in both femoral arteries which was more prominent on the contralateral side. The responses were accompanied with decreases in the blood flow of other vascular beds with only a slight increase or minimal change in ABP. 4. The data suggest that DCRA and VCRA are both viscerotopically organized to alter the resistance of individual vascular beds for redistribution of blood flow. 相似文献
85.
Satomi Kitagawa Yu Yamaguchi Emiko Sameshima Masaru Kunitomo 《Clinical and experimental pharmacology & physiology》1994,21(12):963-970
1. Endothelium-dependent relaxation in response to acetylcholine (ACh) and the calcium ionophore A 23187 was examined in aorta, coronary, basilar and renal arteries isolated from Watanabe heritable hyperlipidaemic (WHHL) rabbits of 2, 6 and 12 months of age, with normolipidaemic heterozygous WHHL rabbits as controls. 2. In the rings of WHHL rabbit aortae and coronary arteries preconstricted with vasoconstrictors, endothelium-dependent relaxation in response to ACh was attenuated with age compared to the heterozygous WHHL rabbits. A significant negative correlation was found between the total cholesterol content and the relaxation response to ACh in the aortae or coronary arteries from 6 and 12 month old WHHL rabbits. 3. In the rings of basilar arteries, endothelium-dependent relaxations to ACh were not modified with age. Similarly, in the rings of renal arteries, the relaxation response to ACh was not changed with age, but in the 6 and 12 month preparations, after the age of 6 months, a contraction following the relaxation appeared at higher concentrations of ACh (10?7 to 10?6 mol/L). The contraction was endothelium-dependent and inhibited by indomethacin. 4. A 23187-induced endothelium-dependent relaxations were also markedly attenuated in the aorta and significantly in the coronary artery with age. 5. Endothelium-independent relaxation to sodium nitroprusside was not changed in all arteries from WHHL rabbits of different ages. 6. These findings indicate that in the aorta and coronary artery of the WHHL rabbit, the endothelium-dependent relaxation to ACh and A 23187 becomes impaired with increasing age (i.e., with the progression of cholesterol deposition in the arterial wall) but is preserved in the basilar and renal artery. 相似文献
86.
John F. Marwood 《Clinical and experimental pharmacology & physiology》1994,21(5):417-425
1. Isolated perfused rat tail artery preparations were used to investigate the effects of the angiotensin converting enzyme inhibitor enalaprilat on the actions of a series of α-adrenoceptor antagonists. The agonist used was phenylephrine. 2. Enalaprilat (1 μmol/L) potentiated the competitive α1-adrenoceptor antagonist actions of phentolamine (10–100 nmol/L) and yohimbine (0.3–3.0 μmol/L) as well as the non-competitive antagonist action of phenoxybenzamine (50–100 pmol/L). 3. The competitive α1-adrenoceptor antagonist action of prazosin (1–10 nmol/L) was not affected by enalaprilat. 4. For the competitive α1-adrenoceptor antagonists, including prazosin, there appeared to be an inverse relationship between antagonist potency and the extent of potentiation by enalaprilat. 5. The results support the hypothesis and angiotensin II modulates vascular smooth muscle α1-adrenoceptor function. 相似文献
87.
J. R. Bernstein B. M. Manzione R. C. Pohland R. B. Franklin 《Biopharmaceutics & drug disposition》1994,15(2):137-150
Tissue distribution studies, utilizing whole-body autoradiography and organ dissection techniques, were conducted in male Fischer 344 rats following the oral administration of 14C-dapoxetine HCl, a potent serotonin reuptake inhibitor. The preliminary study using whole-body autoradiography proved invaluable in locating radioactivity in an organ not usually harvested in a tissue distribution study, namely the preputial gland. Selected organs, based on whole-body autoradiography findings, were dissected from rats and analyzed for radiocarbon content by liquid scintillation counting and for parent drug and N-dealkylated metabolites by extraction and HPLC analysis. Highest concentrations of radiocarbon were observed in the organs of absorption and elimination (ileum, cecum, stomach, duodenum, liver, colon, and kidney) but notable quantities were observed in the lung and preputial and Harderian glands. Most tissues had returned to background radioactive levels 72 h after dosing but persistent concentrations of radiocarbon were present in the preputial gland and liver one week after the single dose of 14C-dapoxetine. Analysis by HPLC demonstrated the presence of parent drug and N-desmethyl metabolite (nor-dapoxetine) in those organs examined; however, the majority of the radioactivity remained unidentified. 相似文献
88.
Dongrun Tang Guoxiang Song Shimin Cui Lingen Chen Qingbin LiDepartment of Ophthalmology the Second Affiliated Hospital Tianjin Medical UniversityTianjin ChinaDepartment of Neurosurgery Tianjin Huan Hu Hospital 《眼科学报》1994,(3)
By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162. 相似文献
89.
汽车驾驶员心电多相频谱分析 总被引:2,自引:0,他引:2
对117例汽车司机应用HBD-1心电多信息诊断仪进行心电多相频谱分析,其功率谱,传递相移,幅度直方图等五项指标总分阳性率明显高于对照组,随着驾车年限的增加,总分阳性率有升高趋势,心电频谱分析对230例冠心病病人阳性检出率84.78%。研究认为汽车司机是易发高血压,冠心病的危险人群,该方法在冠心病的环境流行病学研究中具有重要的临床,亚临床意义。 相似文献
90.
髂内动脉结扎术是控制妇产科手术中大出血的有效措施。本文收集此类患者21例,行双侧髂内动脉结扎15例,单侧6例,均达到了满意的止血效果。笔者介绍了馆内动脉结扎术的方法和临床应用,以及预防髂内静脉损伤和误扎髂多外动脉的具体措施。着重提出髂内动脉结扎后再局部止血才能完全控制盆腔大出血。 相似文献