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61.
目的提高医院临时处方溃结Ⅰ号保留灌肠剂的稳定性,并对其中的主要成分含量进行控制。方法制备时加入助悬剂,用沉降容积比和再分散性选择适宜的助悬剂及其最佳助悬浓度,并用紫外分光光度法对主要成分柳氮磺吡啶的含量进行测定。结果在制剂中加入卡波母作为助悬剂0.15%就可以达到良好的助悬效果,而且制备的制剂再分散性好。结论加入卡波母作为助悬剂制备的制剂稳定,再分散性好,便于使用和保存。  相似文献   
62.
Methotrexate is an anti-proliferative agent that affects both T-cell and B-cell immunity, and therefore might be expected to suppress antibody (Ab) production. Although it has been used in xenotransplantation studies to suppress anti-pig Ab production, it has always been used in combination with other immunosuppressants. The purpose of this study was to measure its effect as a single immunosuppressant on anti-Gal Ab production in baboons (n=4). Pharmacokinetic studies showed that methotrexate was not detected in the blood when administered per os. Prolonged daily IV or IM administration (i) reduced T-cell and B-cell numbers by 50% to 70% and modestly reduced responsiveness on mixed lymphocyte reaction (but only at toxic doses) and (ii) did not result in lowered anti-Gal Ab levels, only marginally reducing the rate of return of Ab after extracorporeal immunoadsorption. Our observations would suggest that methotrexate will not contribute significantly to immunosuppressive regimens in the baboon at non-toxic doses.  相似文献   
63.
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.  相似文献   
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黄柏及中成药中小檗碱和巴马亭的高效液相色谱法测定   总被引:6,自引:0,他引:6  
本文以正相高效液相色谱法,用窗口图解技术对色谱条件进行了优化。对黄柏及其中成药中的有效成分——小檗碱、巴马亭的提取、测定条件、标准曲线进行了研究。并对两种含黄柏的中成药样品进行了分析。其中小檗碱的回收率均在97%以上,巴马亭的回收率均在96%以上。  相似文献   
66.
The recent Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC) reiterated long-standing recommendations that Stage 1 hypertension (BP ≥ 140/90 mm Hg) without comorbidity should be treated initially with diuretics (DI) or beta blockers (BB). Yet market research suggests that many physicians prefer to use other drug classes, such as calcium channel blockers and ACE inhibitors.
OBJECTIVES: To explore the determinants of therapeutic choice in hypertension.
METHODS: We surveyed by mail a stratified random sample of 10,000 U.S. cardiologists, internists, and family/general practitioners. Physicians were queried about their practice environment and their knowledge, attitudes, and practices regarding antihypertensive therapy, including their choice of drugs to treat patients with specified clinical profiles. The probability that physicians would follow JNC guidelines Stage 1 hypertension was analyzed using multiple logistic regression with stepwise backward elimination to select variable with p < 0.001.
RESULTS: Completed surveys were received from 1,023 physicians. 86.7% prescribe drug therapy for Stage 1 hypertension, and 19.5% (22.5% of drug prescribers) limit their choices to DI and BB. Guideline conformity was higher among physicians who: practice in academic medical centrers; are older; are general practitioners (versus general internists); have smaller caseloads; have fewer hypertensive patients; have higher proportions of HMO, Medicaid, and uninsured patients; and experience more formulary restrictions. Cardiologists and family practitioners were less likely than internists to follow guidelines.
CONCLUSION: JNC guidelines are better accepted by academic physicians, older physicians who have more expenence using DI and BB, physicians with smaller caseloads and hence more time for follow-up and therapy adjustment, and physicians who face drug reimbursement constraints.  相似文献   
67.
Rats display a marked sex difference in the oxidation of the pyrrolizidine alkaloid senecionine, especially with respect to N-oxidation. This sex difference was largely eliminated following treatment with dexamethasone. These observations suggested the potential involvement of the male-specific cytochrome P-450 UT-A and the P-450 PCN-E in the metabolism of this pyrrolizidine alkaloid. Reconstituted rat P-450 UT-A exhibited a high rate of N-oxidation (15 nmol min-1 nmol P-450-1) which is almost 3-fold higher than the turnover number observed with male rat liver microsomes. In contrast, rat P-450 UT-A displayed a much lower activity toward necine pyrrole [+/-)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine, DHP) formation (1.0 nmol min-1 nmol P-450-1). The N-oxygenation and pyrrole formation activities displayed by rat cytochromes P-450 PB-B and P-450 BNF-B toward senecionine were low, with rates less than 1 nmol min-1 nmol P-450-1. Rabbit antibody to rat P-450 UT-A inhibited the senecionine-N-oxidation activity of untreated male rat liver microsomes by 60%, with lesser inhibition of DHP production. Rabbit antibody to human P-450NF (the human homologue to rat P-450 PCN-E) was a potent inhibitor of DHP production by untreated male rat liver microsomes. With microsomes from dexamethasone-pretreated rats, anti-P-450NF inhibited DHP and N-oxide production in parallel. We conclude that the large sex difference in senecionine N-oxidation probably is the result of the specificity of P-450 isozymes UT-A and PCN-E.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
68.
从秋季采收的菊科植物大丁草Gerbera anandria(L.)Sch Bip.全草中共分出十三种成分。本文报道其中三个新化合物的结构鉴定.它们分别是3,8-dihydroxy-4-methoxy-coumarin(ⅪⅩ),3,8-dihydroxy-4-methoxy-2-oxo-2 H-1-benzopyran-5-carboxylic acid(ⅩⅦ),和5,8-dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3-)-coumarin(ⅩⅪ)。  相似文献   
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目的:为保护濒死心肌提供机会窗口,对比观察经冠脉移植自体骨髓单个核细胞或间充质干细胞后,实验性急性心肌梗死动物心功能变化及心肌组织核转录因子кB、心肌细胞凋亡情况。方法:实验于2005-03/2006-11在河北省人民医院实验中心完成。选用24只雄性冀中白猪,随机数字表法分为4组:正常对照组、模型组、单个核细胞组、间充质干细胞组,6只/组。①24只猪均以盐酸氯胺酮200mg臀部肌肉注射麻醉后,分别于各自右侧股骨抽取骨髓20mL,采用Fercoll法分离获得骨髓单个核细胞,加入胶体金溶液,培养12~16h待用。分离过程中取出含有骨髓单个核细胞成分的细胞层,常规培养传代,每3d换液1次,贴壁生长细胞即为骨髓间充质干细胞,加入胶体金溶液,培养24h待用。②除正常对照组外,其余各组均经导管球囊封闭第一对角支以远的前降支,复制猪急性心肌梗死模型。单个核细胞组、间充质干细胞组均于造模后立即开通前降支,分别经球囊注入预先分离的骨髓单个核细胞6×108个、间充质干细胞6×108个。模型组造模后于梗死1h开通前降支,经球囊注入磷酸盐缓冲液10mL。③各组分别于术前及术后4周经心脏超声检测心功能,取材行病理学检查、心肌组织核转录因子кB的免疫组织化学检测及心肌细胞凋亡检测。结果:24只雄性白猪均进入结果分析。①心功能变化:术前各组左心室收缩末内径、左心室舒张末内径、左心室射血分数、短轴缩短率基本相似。移植术后4周,正常对照组、单个核细胞组、间充质干细胞组左心室舒张末内径均明显低于模型组(F=4.68,P=0.01),左心室射血分数及短轴缩短率均明显高于模型组(F=5.14,P=0.01;F=3.32,P=0.04),各组左心室收缩末内径差异无显著性意义(F=1.64,P=0.21)。②心肌组织病理学改变:电镜下单个核细胞组、间充质干细胞组在梗死边缘区可见有胶体金颗粒的不成熟的心肌细胞,胞质中散在肌丝结构,肌丝排列紊乱不规则。③心肌组织核转录因子кB阳性率表达:与模型组比较,单个核细胞组、间充质干细胞组的梗死边缘区核转录因子кB阳性率明显降低(F=25.59,P=0.0001);正常心肌区核转录因子кB阳性率亦明显降低(F=18.20,P=0.0001)。④心肌细胞凋亡检测结果:与模型组比较,单个核细胞组、间充质干细胞组在心肌梗死区细胞凋亡率均明显降低(F=6.63,P=0.0027),梗死边缘区细胞凋亡率亦明显降低(F=36.07,P=0.0001)。正常心肌区单个核细胞组细胞凋亡率与模型组基本相似(F=9.69,P=0.004),但间充质干细胞组有所降低。⑤心功能与心肌细胞凋亡及心肌组织NF-кB的相关性:急性心肌梗死4周时,左心室射血分数与心肌细胞凋亡、心肌组织核转录因子кB均呈负相关(r=0.613,P=0.001;r=-0.437,P=0.033)。心肌细胞凋亡与心肌组织核转录因子кB呈正相关(r=0.672,P=0.002)。结论:经冠脉移植骨髓单个核细胞和间充质干细胞均可改善实验性急性心肌梗死动物的心功能,与梗死边缘区核转录因子кB表达降低及心肌细胞凋亡减少有关。骨髓单个核细胞移植的促血管增生作用优于间充质干细胞移植。  相似文献   
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