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51.
用高效液相色谱法测定胃脘舒冲剂中甘草酸的含量,采用 μBondapak C_(18)柱, 3. 9 mm ×300 mm,流动相甲醇-1. 5 mol/L冰醋酸水溶液(68: 32),流速 1. 0 mL/min,检测波长 254 nm,测定结果平均回收率为97.41%,RSD=1.2%。  相似文献   
52.
Summary Partially purified chromaffin granules (granular fraction), crude mitochondria (mitochondrial fraction) and a microsomal fraction were prepared from bovine adrenals by differential centrifugation and characterized by their catecholamine content, succinate dehydrogenase and glucose-6-phosphatase activity. During isotonic incubation with 0.1 mM 45Ca2+ all fractions showed an uptake of 45Ca2+, which was stimulated by ATP. In addition, after incubation the granular fraction was further fractionated by sucrose density gradient centrifugation (2.0–1.3 M sucrose; 170,000g·60 min). In some of these experiments the granular fraction was incubated simultaneously with 45Ca2+ and [3H](-)noradrenaline to compare the uptake of both. The rate of uptake of 45Ca2+ into the 2.0 M sucrose fraction (characterized by the highest catecholamine content and the lowest succinate dehydrogenase activity) was doubled by ATP. The ATP-stimulated uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules was inhibited by N-ethylmaleimide (NEM) (0.1 mM), 2,4-dinitrophenol (DNP) (0.1 mM), azide (1 mM), carbonyl cyanide mchlorophenylhydrazone (CCCP) (20M), atractyloside (50 M), ruthenium red (40 M) and amobarbital (1 mM). This inhibition pattern was different from that of the ATP-stimulated uptake of 45Ca2+ into the microsomal fraction, but it was similar to that of the ATP-stimulated uptake of 45Ca2+ into the mitochondrial fraction. However, the following differences are incompatible with the view that a mitochondrial contamination, with a highly active uptake, is responsible for the ATP-stimulated uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules: a) The uptake of 45Ca2+ into the mitochondrial fraction was insensitive to 1 mM amobarbital, whereas this agent inhibited the uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules. b) Replacement of ATP by succinate stimulated the uptake of 45Ca2+ into the mitochondrial fraction only. c) The dependence of the ATP-stimulated uptake of 45Ca2+ on the concentration of ATP (0.1–5 mM) was determined: while uptake into the 2.0 M sucrose fraction of chromaffin granules exhibited saturation kinetics, that into the mitochondrial fraction was linearly related to the concentration of ATP. Interestingly, uptake of 45Ca2+ into those fractions of chromaffin granules that are known to be contaminated with mitochondria (1.6 M sucrose fraction) exhibited bot a saturable and a nonsaturable component. d) The uptake of 45Ca2+ into the mitochondrial fraction was more sensitive to 0.1 mM DNP than the uptake of 45Ca2+ into the 2.0 M sucrose fraction of chromaffin granules.The comparison of the ATP-stimulated uptake of 45Ca2+ with that of [3H](-)noradrenaline into the 2.0 M sucrose fraction of chromaffin granules revealed that amobarbital, N,N-dicyclohexylcarbodiimide (DCCD), DNP and increasing concentrations of ATP had the same influence on both uptake processes. From our results we conclude that an inherent, ATP-stimulated uptake of 45Ca2+ exists in chromaffin granules. The effects of agents on the uptake of 45Ca2+ and/or [3H](-)noradrenaline into chromaffin granules are discussed with regard to the granular uptake mechanisms.This work was supported by the Deutsche ForschungsgemeinschaftSome results were reported at the 18th Spring Meeting 1977 of the Deutsche Pharmakologische Gesellschaft (Burger and Häusler 1977)  相似文献   
53.
Primary infiltrating signet ring carcinoma of the eyelids   总被引:1,自引:0,他引:1  
A 61-year old man presented with a five-year history of a swelling initially developing in his right lower lid that progressed to involve the lateral canthal skin and eventually the upper lid and anterior orbit. He was discovered to have an infiltrating, poorly differentiated, mucin-producing carcinoma. Systemic work-up failed to disclose a visceral malignancy, and it was concluded that his tumor was primary in the lids, arising from an adnexal sweat gland. Three other reports in the literature also share almost identical clinical and pathologic features, in that all of the earlier reports dealt with middle-aged or elderly men who had diffusely indurated lids. Histopathologically, the tumor cells grow diffusely in a sclerotic stroma, and resemble the "histiocytoid" variant of metastatic breast carcinoma to the lids in women. Ultrastructural studies in our case point toward an apocrine origin, although earlier authors have favored an eccrine origin. Despite its indolent clinical course, the tumor is capable of producing regional and distant metastases on long-term follow-up. Complete local excision, possibly necessitating radical surgery, is probably the preferred method of treatment, but local radiotherapy may have a beneficial effect in retarding spread of the disease.  相似文献   
54.
The Merkel cell is a distinctive nondendritic, nonkeratinocytic, epithelial clear cell believed to migrate from the neural crest to the epidermis and dermis, which is usually located in or near the basal layer of the epidermis and associated with nerve terminations. Merkel first described these cells in 1875 as "Tastzellen" occurring in the snout of a mole. They are believed to function as slowly adapting mechanoreceptors that mediate the sense of touch. Tumors arising from Merkel cells have been reported to occur on the head and neck area, the trunk, arms, and legs, and resemble a primary cutaneous lymphoma or cutaneous metastasis of a lymphoma or a carcinoma. Electron microscopy, to locate the characteristic membrane-bound, dense core neurosecretory granules, is needed for accurate diagnosis. These tumors must be treated aggressively to minimize the chance of local recurrence and nodal or visceral metastases. The authors present a case of Merkel cell tumor occurring on the eyelid. The clinical history, light and electron microscopic findings are shown.  相似文献   
55.
板蓝根醇沉物的药理作用   总被引:5,自引:0,他引:5  
目的:观察板蓝根醇沉物与板蓝根颗粒剂的差异。方法:对比研究板蓝根醇沉物与板蓝根颗粒剂前浸膏的药理作用。结果:板蓝根醇沉物的热解、抗炎及抗茵作用与同剂量板蓝根颗粒剂前浸膏相同,其靛蓝含量高于板蓝根颗粒剂前浸膏。结论:板蓝根醇沉物有明显的解热、抗炎作用,板蓝根制剂传统制备工艺有待改进。  相似文献   
56.
尿石通颗粒中总黄酮的含量测定   总被引:2,自引:0,他引:2  
目的:测定尿石通颗粒中总黄酮的含量。方法:用70%乙醇提取并制成供试品,采用分光光度法测定。结果:平均回收率为98.28%,RSD=2.13%。3批尿石通颗粒样品中总黄酮的含量分别为1.448,1.403,1.427 mg·g~(-1)。结论:本方法简便、准确、灵敏度高,可作为该制剂的质量控制方法。  相似文献   
57.
头孢克洛缓释片在健康人体的药代动力学及生物等效性   总被引:3,自引:0,他引:3  
目的 研究头孢克洛两种缓释片在健康志愿者体内的药代动力学和相对生物利用度。方法 20名健康男性受试者随机交叉单剂量及多剂量口服受试制剂375mg和参比制剂375mg,用液相色谱一串联质谱法测定给药后不同时刻的血浆浓度,求得主要药代动力学参数。结果 单剂量口服获得的主要药动学参数,t_(max)分别为2.23±0.64和2.05±0.56 h,C_(max)分别为2.54±0.89和2.38±0.65 mg·L~(-1),AUC_(0-t)分别为7.38±1.66和7.09±1.71 mg·h.L~(-1),t_(1/2)分别为1.08±0.12和1.07±0.13h,F为(105.0±11.2)%。多剂量口服获得的主要药动学参数AUC_(ss)分别为7.22±1.37和7.02±1.53mg·h·L~(-1),C_(max)分别为2.61±0.61和2.34±0.55 mg·L~(-1),C_(min)分别为3.48±1.33和3.65±1.23 μg·L~(-1),C_(av)分别为602±114和585±128μg·L~(-1),DF分别为4.3±0.7和4.0±0.6,F为(105.5±19.9)%。统计学结果显示,两种制剂的药动学参数无显著性差异,符合生物等效性标准。结论 头孢克洛两种缓释片均具有较好的缓释特征,两种制剂生物等效。  相似文献   
58.
毕庆贵  高红 《黑龙江医药》2003,16(6):509-510
目的:研究越桔冲剂对正常及致敏豚鼠支气管平滑肌的影响。方法:通过实验,观察越桔冲剂对磷酸组织胺引起正常豚鼠支气管收缩的影响。结果:实验证明,越桔冲剂10ml·kg~(-1)对磷酸组织胺致正常豚鼠支气管收缩具有对抗作用(P<0.01)。结论:越桔冲剂具有显著的平喘作用。  相似文献   
59.
金叶败毒颗粒对孕鼠免疫和生殖功能影响的研究   总被引:2,自引:0,他引:2  
赵捷  闻良珍  陈素华  凌霞珍 《中成药》2003,25(2):130-132
目的 :探讨中药金叶败毒颗粒 (金银花、鱼腥草、大青叶等 )对孕鼠免疫功能的作用 ,以及其对孕鼠和子代发育安全性的影响。方法 :设试验组、空白组和阳性组 3组 ,给试验组孕鼠孕期持续灌服高剂量的金叶败毒颗粒 ,观察各组仔鼠骨骼、器官和染色体发育情况 ;分别测定孕鼠分娩前外周血免疫细胞数、腹腔巨噬细胞数、脾淋巴细胞激活实验和NK细胞活性。结果 :三组孕鼠一般情况和仔鼠发育无明显差异 ;试验组孕鼠外周血免疫细胞、腹腔巨噬细胞数明显增多 ,脾淋巴细胞A值和NK细胞活性明显高于两对照组 (P <0 .0 5)。结论 :金叶败毒颗粒对孕鼠及子代无毒副作用 ,能显著提高孕鼠免疫功能 ,可对孕期发生的生理性免疫功能降低起保护作用  相似文献   
60.
目的:建立口腔愈疡颗粒的质量标准。方法:采用高效液相色谱法对成品中芍药苷进行含量测定。结果:芍药香浓度线性范围为:0.104—0.520μg/ml,γ=0.9993。样品平均回收率为98.85%,RSD为1.27%(n=5)。结论:该方法适用于口腔愈疡颗粒的质量控制。  相似文献   
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