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1.
酞丁安对映体合成及其抗单纯疱疹病毒活性评价   总被引:1,自引:0,他引:1  
酞丁安(3-酞酰亚胺-2-氧-正丁醛双缩氨硫脲,TDA)是药物研究所创制的抗病毒新药。为了研究其对映异构体(R),(S)-TDA对病毒活性及毒性是否有差异,并与消旋酞丁安(RS)-TDA的抗病毒活性及毒性进行比较,本文分别用已知构型的(R)-与(S)-丙氨酸为原料,通过缩合等6步反应,得到光学活性的(R)-,(S)-TDA,并与外消旋酞丁安比较其抗病毒活性及毒性。三者的抗单纯疱疹病毒活性与对细胞的毒性差别不大,说明消旋酞丁安临床使用是安全有效的。  相似文献   
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李陕区  闫小君 《医学争鸣》2000,21(7):F002-F002
0 引言 转化生长因子 β1(TGFβ1)可抑制肝细胞增生 ,抑制肝细胞生长因子 (HGF)对肝细胞有丝分裂的促进作用 .肝炎患者肝组织中 TGFβ1和 HGF的 m RNA表达明显增加 ,它能表达乙型肝炎病毒 (HBV) X基因 (HBX)的转基因小鼠中HBX基因可激活 TGFβ1基因的转录 [1 ,2 ] .我们对急慢性乙型肝炎和肝硬化患者血清进行 TGFβ1和 HBX蛋白测定 ,并研究它们的变化及意义 .1 对象和方法1.1 对象 急性乙型肝炎 (AHB)患者 19(男 13,女 6 )例 ,年龄 18~ 45岁 ;慢性乙型肝炎患者 2 2 (男 15 ,女 7)例 ,年龄 2 2~48岁 ;肝硬化 (L C) 2 …  相似文献   
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The number of times an article is cited in scientific journals reflects its impact on a specific biomedical field or specialty and reflects the impact of the authors’ creativity. Our objective was to identify and analyze the characteristics of the 100 most frequently cited articles published in journals dedicated to general surgery and its close subspecialties. Using the database (1945–1995) of the Science Citation Index of the Institute for Scientific Information, 1500 articles cited 100 times and more were identified and the top 100 articles selected for further analysis. The 100 articles were published between 1931 and 1990, with more than two-thirds of them published after 1960. The mean number of citations per article was 405, (range 278–1013). Altogether, 84 of the articles originated from North America (USA 78, Canada 6) and the UK (12). New York State led the list of U.S. states with 14, and Harvard and Columbia University led the list of institutions with 6 articles each. The 100 articles were published in 10 surgical journals led by theAnnals of Surgery (n = 40), followed bySurgery (n = 15), Archives of Surgery (n = 12), Surgery, Gynecology and Obstetrics (n = 11), and British Journal of Surgery (n = 10). A total of 80 of the articles reported clinical experiences, 6 were clinical review articles, and 14 dealt with basic science. Eighteen articles reported a new surgical technique and six a prosthetic device. Gastrointestinal surgery and trauma and critical care led the list of the surgical fields, each with 25 articles, followed by vascular surgery (n = 15). Thirty-four persons authored two or more of the top-cited articles. This list of the top-cited papers identifies seminal contributions and their originators, facilitating the understanding and discourse of modern surgical history and offering surgeons hints about what makes a contribution a "top-cited classic." To produce such a "classic" the surgeon and his or her group must come up with a clinical or nonclinical innovation, observation, or discovery that has a long-standing effect on the way we practice—be it operative or nonoperative. Based on our findings, to be well cited such a contribution should be published in the English language in a high-impact journal. Moreover, it is more likely to resonant loudly if it originates from a North American or British "ivory tower."  相似文献   
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Two new sulfated steroidal pentaglycosides(asterosaponins),novaeguinosides Ⅰ(2) and (Ⅱ)2,along with the known regularoside B(1)were isolated from the starfish Culcita novaeguineae.Their structures were elucidated by extensive NMR techniques as well as chemical evidence.  相似文献   
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Aortic graft infection is one of the most dreaded surgical complications. In the perioperative patient with fresh aortic prosthesis, this is a particularly complex problem. Opening the bowel changes an operation to a "clean-contaminated" or "contaminated" case. This increases the risk of all infectious complications in the patient. Theoretically, our method of repair reduces the risk of infection by eliminating the duodenotomy. The direct visualization with the endoscope replaces the need to open the potentially contaminated bowel and reduces the risk of bacterial translocation and bacteremia. By not opening the bowel, this keeps the case "clean," and likely reduces the risk of contamination and subsequent infection of the prosthetic graft. As the potential morbidity of aortic graft infection is so devastating, and now that we have the available technology and operative skill, we propose our technique as a potential alternative to possibly reduce the incidence of aortic graft infection.  相似文献   
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从平贝母茎叶中分离的平贝啶甙的结构   总被引:2,自引:0,他引:2  
本文报道自平贝母(Fritillaria ussuriensis Maxim)的地上茎叶中分得一种新的甾体生物碱甙,定名为平贝啶甙(pingbeidinoside),mp 242~243.2℃[a]D25+6.9°(c 0.145,MeOH)。经IR,MS,1HNMR和13CNMR谱解析,推定其结构为3β,16α,20-三羟基-Δ5-22,26-缩亚胺胆甾烷-25-O-α-D-葡萄糖甙。  相似文献   
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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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学术背景:中医药在防治骨质疏松症方面具有独特优势,但目前关于该病的中药复方用药规律的研究较少,而且多以统计用药频率为主。此法往往需要大样本且须具有典型的概率分布。此外,在中医诊治过程中,个人经验也造成处方配伍用药的偏倚,药物剂量相距甚远,这使药物治疗的安全性和有效性难以保证。目的:应用灰关联分析及信息处理方法探讨治疗骨质疏松症的用药规律。 检索策略:由第一、三、四作者应用计算机检索中国知网1995-01/2005-12期间的相关文献。所用中文检索词包括“骨质疏松,骨萎,中药,治疗”。共检索到169篇文献。纳入标准:①治疗方法为单纯使用中药治疗,不包括其他辅助治疗,如西药、手法、针灸等。②所有中药复方必须药味完整,剂量准确,主治明确,疗效确切。排除标准:排除含有辅助治疗及疗效不确切,药味不全、没有给出药物剂量或剂量不准确的文献。结果选出104篇符合标准的文章。 文献评价:文献的来源主要是通过对治疗骨质疏松症的中药复方的相关文章进行循证医学系统查询,通过灰关联分析及信息处理方法分析查询结果,以此探讨治疗骨质疏松症的中药复方用药规律。资料综合:在治疗骨质疏松症的104首中药复方中共使用106种药物1204频次。其中,使用频次在10次以上的依次为熟地、淫洋藿、杜仲等34味中药,使用总频次为890次,灰关联系数大小依次为山药、淫羊藿、骨碎补等。性温、平,味甘、苦、辛,归肾经、肝经和脾经的药物所占比例较大。在药物分类中,补益药达到23种,占总数的67.6%。其中,又以补阳药为主,其次为补气药。 结论:灰关联分析及信息处理结果认为骨质疏松症的主要病理是脾肾阳虚,其次为气虚、阴虚和血虚,在用药中主要使用补益肝肾、补脾益气、滋阴活血药。  相似文献   
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