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Quality of bowel preparation in patients with inflammatory bowel disease undergoing colonoscopy:What factors to consider? 被引量:2
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作者 Antonietta Gerarda Gravina Raffaele Pellegrino +9 位作者 Mario Romeo Giovanna Palladino Marina Cipullo Giorgia Iadanza Simone Olivieri Giuseppe Zagaria Nicola De Gennaro Antonio Santonastaso Marco Romano Alessandro Federico 《World Journal of Gastrointestinal Endoscopy》 2023年第3期133-145,共13页
An adequate bowel preparation in patients with inflammatory bowel disease(IBD)is a prerequisite for successful colonoscopy for screening,diagnosis,and surveillance.Several bowel preparation formulations are available,... An adequate bowel preparation in patients with inflammatory bowel disease(IBD)is a prerequisite for successful colonoscopy for screening,diagnosis,and surveillance.Several bowel preparation formulations are available,both high-and low-volume based on polyethylene glycol.Generally,low-volume formulations are also based on several compounds such as magnesium citrate preparations with sodium picosulphate,oral sulphate solution,and oral sodium phosphatebased solutions.Targeted studies on the quality of bowel preparation prior to colonoscopy in the IBD population are still required,with current evidence from existing studies being inconclusive.New frontiers are also moving towards the use of alternatives to anterograde ones,using preparations based on retrograde colonic lavage. 展开更多
关键词 Bowel preparation COLONOsCOPY Inflammatory bowel disease Crohn’s disease Ulcerative colitis Artificial intelligence
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Emerging space for non-polyethene-glycol bowel preparations in inflammatory bowel disease-related colonoscopy:Veering toward better adherence and palatability 被引量:1
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作者 Raffaele Pellegrino Antonietta Gerarda Gravina 《World Journal of Gastroenterology》 SCIE CAS 2023年第46期6022-6027,共6页
Patients with inflammatory bowel diseases(IBDs)require repeated endoscopic evaluations over time by colonoscopy to weigh disease activity but also for different and additional indications(e.g.,evaluation of postoperat... Patients with inflammatory bowel diseases(IBDs)require repeated endoscopic evaluations over time by colonoscopy to weigh disease activity but also for different and additional indications(e.g.,evaluation of postoperative recurrence,colorectal cancer surveillance).Colonoscopy,however,requires adequate bowel preparation to be of quality.The latter is achieved as long as the patient takes a certain amount of product to have a number of bowel movements suitable to clean the colon and allow optimal visualization of the mucosa during endoscopy.However,significant guidelines recommend preparations for patients with IBD not excelling in palatability.This recommendation originates from the fact that most of the studies conducted on bowel preparations in patients with IBD have been done with isosmolar preparations based on polyethylene glycol(PEG),for which,therefore,more safety data exist.As a result,the low-volume non-PEG preparations(e.g.,magnesium citrate plus picosulphate,oral sulphate solutions)have been set aside for the whole range of warnings to be heeded because of their hyperosmolarity.New studies,however,are emerging,leaning in overall for a paradigm shift in this matter.Indeed,such non-PEG preparations seem to show a particularly encouraging and engaging safety profile when considering their broad potential for tolerability and patient preference.Indeed,such evidence is insufficient to indicate such preparations in all patients with IBD but may pave the way for those with remission or well-controlled disease.This article summarizes the central studies conducted in IBD settings using non-PEG preparations by discussing their results. 展开更多
关键词 Inflammatory bowel disease Crohn’s disease Ulcerative colitis Bowel preparation COLONOsCOPY Polyethylene glycol Low-volume
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Protective effects of kidney-tonifying Chinese herbal preparation on substantia nigra neurons in a mouse model of Parkinson's disease 被引量:7
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作者 Jing Cai Yun Tian +3 位作者 Ruhui Lin Xuzheng Chen Zhizhen Liu Jindong Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第6期413-420,共8页
The Chinese herbs Herba Epimedii, Fructus Ligustri Lucidi and Rhizoma Polygonati were injected into Parkinson's disease mice established via intraperitoneal injection of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridin... The Chinese herbs Herba Epimedii, Fructus Ligustri Lucidi and Rhizoma Polygonati were injected into Parkinson's disease mice established via intraperitoneal injection of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine hydrochloride. The selective monoamine oxidase B inhibitor selegiline was used as a positive control drug. After successive administration for 4 weeks, Herba Epimedii could downregulate the expression of caspase-3 and increase the brain-derived neurotrophic factor level, as well as increase tyrosine hydroxylase activity in the substantia nigra of Parkinson's disease mouse models. Rhizoma Polygonaticould downregulate the expression of caspase-3 and FasL, and increase neural growth factor and brain-derived neurotrophic factor levels. Fructus Ligustn Lucidi could downregulate caspase-3 expression. Rhizoma Polygonati and Fructus Ligustn Lucidi did not produce obvious effects on tyrosine hydroxylase activity. Herba Epimedii and Fructus Ligustri Lucidi yielded similar effects on apoptosis-promoting factors to those elicited by selegiline. Herba Epimedii and Rhizoma Polygonati significantly increased the levels of neurotrophic factors compared with selegiline. Herba Epimedii significantly increased tyrosine hydroxylase activity compared with selegiline. It is indicated that the kidney-tonifying Chinese herbal preparation can downregulate the expression of apoptosis-promoting factors, increase neurotrophic factors levels in the substantia nigra and striatum, as well as increase tyrosine hydroxylase activity in the substantia nigra of Parkinson's disease mouse models, thereby exerting a stronger or similar neuroprotective effects compared with selegiline. 展开更多
关键词 kidney-tonifying Chinese herbal preparation Herba Epimedii Fructus Ligustri Lucidi Rhizoma Polygonati Parkinson's disease substantia nigra and striatum substantia nigra neuron neural regeneration
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Preparation and Inhibitory Effects of 20(S)-Ginsenoside Rh_2 on Hep-A-22 Cells
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作者 ZHOU Hong-yu JIN Yong-ri +4 位作者 WEI Wei SHI Xiao-lei YANG Rui-jie YANG Shi-jie LI Xu-wen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第4期567-571,共5页
A modified method of preparing 20(S)-ginsenoside Rh2(G-Rh2) and the inhibitory effect of 20(S)-ginsenoside Rh2 on Hep-A-22 cells were investigated. The total saponins and strong alkali were dissolved in glycerol... A modified method of preparing 20(S)-ginsenoside Rh2(G-Rh2) and the inhibitory effect of 20(S)-ginsenoside Rh2 on Hep-A-22 cells were investigated. The total saponins and strong alkali were dissolved in glycerol at the atmospheric pressure, and the degradation was performed at a high temperature. After G-Rh2 had been isolated and purified, MTT(methyl thiazolyl tetrazolium) assay was applied to evaluating the effect of 20(S)-ginsenoside Rh2 on the cells viability and morphological changes were observed. It was shown that 20(S)-ginsenoside Rh2 can reduce Hep-A-22 cells viability in dose-dependent manner and the cells took on cell shrinkage, membrane blebbing, chromosomal condensations, especially under the higher concentrations of it. In conclusion, 20(S)-ginsenoside Rh2 can be prepared effectively that not only decreases viability but also induces the apoptosis of Hep-A-22 cells. 展开更多
关键词 20(s)-Ginsenoside Rh2 preparation Alkaline-degradation Hep-A-22 cell Inhibitory effect
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Preparation of Single Crystals of Co_xZn_(1-x)S and Co_xZn_(1-x)Se—New Materials of Dilute Magnetic Semiconductors
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作者 Gu Xiamin Giriat W. Furdyna J.K.Shanhai Institute of Metallurgy,Academia Sinica 200050 China Department of Physics University of Notre Dame.Indiana 46556,U. S. A 《Rare Metals》 SCIE EI CAS CSCD 1990年第2期139-144,共6页
In this paper, we report the growth of single crystals of Co_x Zn_(1-x)S and Co_x Zn_(1-x)Se (0<x<0.3) by the method of chemical transport, using iodine as a transport agent. The light green color of single crys... In this paper, we report the growth of single crystals of Co_x Zn_(1-x)S and Co_x Zn_(1-x)Se (0<x<0.3) by the method of chemical transport, using iodine as a transport agent. The light green color of single crystal Co_xZn_(1-x)S as well as the light brown color of Co_xZn_(1-x)Se become deep with an increase in x. The compositions of the single crystals were nearly stoichiometric. The transfer rate decreases with an increase of the x value. The growth rate was related to the temperature difference. The large temperature difference speed up the growth rate, but the size of crystal obtained was small. In general, the optimal temperature difference was 15℃. From X-ray diffraction measurements, the structures of crystals Co_xZn_(1-x)S and Co_xZn_(1-x)Se (0<x<0.1) were identified to be zinc blende structure similar to that of ZnS and ZnSe. 展开更多
关键词 CO x)se New Materials of Dilute Magnetic semiconductors preparation of single Crystals of Co_xZn x)s and Co_xZn
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“Buyi Ganshen”,a traditional Chinese medicine treatment,combined with dopa preparation for Parkinson’s disease therapy:a meta-analysis of randomized controlled trials
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作者 Xiao-Qian Hao Wen-Wen Si +8 位作者 Ye Tian Jie Liu Yi-Chun Ji Xin-Rong Li Zi-Feng Huang Yu Zhu Dong-Feng Chen Wei-Hong Kuang Mei-Ling Zhu 《TMR Aging》 2020年第3期97-109,共13页
Traditional Chinese medicine Buyi Ganshen therapy combined with dopa preparation in the therapy of Parkinson’s disease could enhance the clinical safety and efficacy compared with dopa preparation along.The exact mec... Traditional Chinese medicine Buyi Ganshen therapy combined with dopa preparation in the therapy of Parkinson’s disease could enhance the clinical safety and efficacy compared with dopa preparation along.The exact mechanism of how Buyi Ganshen works combined with dopa preparation still unknown and the enrolled articles quality was relatively inadequate,yet it could provide the reference in the clinical application and further studies.Background:To research the influence of“Buyi Ganshen”,a traditional Chinese medicine that commonly used in“Tonifying the Liver and the Kidney”,added dopa preparation for the therapy of Parkinson’s disease.Methods:This meta-analysis examined existing literature by searching 7 electronic databases(CNKI,WanFang,EMBASE,PubMed,Medline,the Cochrane Library,and the VIP database)from inception to December 2019.Randomized controlled trials evaluating the influence of“Buyi Ganshen”combined with dopa preparation for Parkinson’s disease were identified.The main results were clinical efficacy,UPDRS I(mental score),total unified Parkinson’s disease ratingscale score,UPDRS III(motor score),UPDRS II(activities of daily life),and UPDRS IV(complications of treatment).The subordinate results were the SPOCA-AUT scores,traditional Chinese medicine syndromes and other adverse reactions.The Review Manager 5.3 software was used to calculate the pooled estimate effect.The outcomes were showed as relative ratio with 95%confidence interval.The fixed or random model was elected based on the level of homogeneity among researches.The I2 was used to detected heterogeneity.The quality of the researches was also assessed.Results:The meta-analysis include 2,241 individuals from a total of 30 studies.These data suggested that the therapy of Parkinson’s disease with the combination of“Buyi Ganshen”and dopa preparation were more effective compared to dopa preparation alone.Conclusion:“Buyi Ganshen”combined with dopa preparation exists,in some degree,to enhance clinical safety and effectiveness in the cure of Parkinson’s disease,compared with dopa preparation along.As most of the studies included were with low quality,this conclusion must be considered with caution.Thus,more multi-center,high-quality,prospective randomized controlled trials with large enough sample sizes are required to further illuminate the influence of“Buyi Ganshen”combined with dopa preparation for Parkinson’s disease. 展开更多
关键词 Parkinson’s disease Buyi Ganshen Dopa preparation META-ANALYsIs
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Preparation of an imaging agent for cerebral muscarinic acetylcholine receptor, (R,S)(131)~I-QNB
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作者 NING Shi-Yu +2 位作者 LIN Yan-Song 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第1期64-65,共2页
The method to synthesize a high affinity muscarinic receptor antagonist (R,S)I-QNB[(R)-(-)-1-azabicyclo [2,2,2]oct-3-yl-(S)-(+)-α-hydroxy-α-(4-[127I]iodophenyl)-α-phenyl acetate] from 4-nitrobenzophenone with impro... The method to synthesize a high affinity muscarinic receptor antagonist (R,S)I-QNB[(R)-(-)-1-azabicyclo [2,2,2]oct-3-yl-(S)-(+)-α-hydroxy-α-(4-[127I]iodophenyl)-α-phenyl acetate] from 4-nitrobenzophenone with improvement compared to literatures was reported in this article. IR, MS and 1HNMR characterized the final product. (R,S)131I-QNB was prepared using Cu(I) assisted iodine exchange labeling, and showed by TLC that the radiolabeling yield(RLY) was over 80%, and radiochemical purity(RCP) was over 95%. Stability of the labeled compound was also determined. It was found that (R,S)131I-QNB dried by nitrogen blowing can stay at 4-10℃ for a week without change of RCP. 展开更多
关键词 (R s)I-QNB 合成 碘131 放射性同位素 标记 表征 IR Ms NMR
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原人参二醇组皂苷选择性制备人参皂苷20(S)-Rg3和Rg5及其生成机理研究 被引量:1
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作者 张浩然 朱小涵 +3 位作者 张跃伟 李琳 李玲 成乐琴 《食品与发酵工业》 CAS CSCD 北大核心 2023年第2期129-137,共9页
该文以原人参二醇(protopanaxadiol,PD)型皂苷为原料,盐酸为催化剂,选择性制备稀有人参皂苷Rg5和20(S)-Rg3。主要探索了酸浓度、乙醇浓度、反应温度以及反应时间对制备人参皂苷20(S)-Rg3和Rg5的影响,并通过同位素标记法研究了人参皂苷Rg... 该文以原人参二醇(protopanaxadiol,PD)型皂苷为原料,盐酸为催化剂,选择性制备稀有人参皂苷Rg5和20(S)-Rg3。主要探索了酸浓度、乙醇浓度、反应温度以及反应时间对制备人参皂苷20(S)-Rg3和Rg5的影响,并通过同位素标记法研究了人参皂苷Rg3的生成机理。结果表明,当PD型皂苷质量浓度为15 mg/mL,HCl浓度为0.02 mol/L,乙醇体积分数为99%,反应温度为60℃,反应时间为3.5 h时,20(S)-Rg3和Rg5收率分别为15.32%和50.12%,20(S)-Rg3的de值为98.28%。同位素标记法研究反应机理表明,PD皂苷在盐酸催化下高立体选择性地生成Rg3是S_(N)2机理。该方法催化剂价廉易得,操作简单,在生成Rg5的同时又能高立体选择性生成20(S)-Rg3,为一步合成多种高活性稀有人参皂苷提供新的思路。 展开更多
关键词 原人参二醇组皂苷 人参皂苷Rg5 20(s)-人参皂苷-Rg3 选择性制备 生成机理
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Characterization and catalytic behavior of Na-W-Mn-Zr-S-P/SiO_2 prepared by different methods in oxidative coupling of methane 被引量:2
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作者 Wen Zheng Dangguo Cheng Fengqiu Chen Xiaoli Zhan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第5期515-521,共7页
Na-W-Mn-Zr-S-P/SiO2 catalysts for oxidative coupling of methane (OCM) were prepared by incipient wetness impregnation, sol-gel and mixture slurry methods. The catalyst prepared by mixture slurry method showed the be... Na-W-Mn-Zr-S-P/SiO2 catalysts for oxidative coupling of methane (OCM) were prepared by incipient wetness impregnation, sol-gel and mixture slurry methods. The catalyst prepared by mixture slurry method showed the best catalytic performance among all samples. In addition, the effects of different addition sequences of Na, W, Mn, Zr, S and P on the catalytic performance were studied. The absence of Na before the addition of Mn and Zr in the catalysts preparation depressed the formation of the active phases of Mn2O3 and ZrO2 and decreased the activities of the catalysts significantly. 展开更多
关键词 oxidative coupling of methane Na-W-Mn-Zr-s-P/siO2 prepared method
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The Chinese Tobacco Industry Prepares for China's WTO Access
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《China Today》 2001年第7期74-75,共2页
关键词 WTO The Chinese Tobacco Industry prepares for China’s WTO Access
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MII prepares six major measures meet challenges of China's entry into WTO
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《China Standardization》 2007年第2期1-,共1页
  Jiang Yaoping,  Vice Minister of MII (Ministry of Information Industry), has introduced six major preparations and measures of China information industry to meet challenges of China's entry into WTO at the c...   Jiang Yaoping,  Vice Minister of MII (Ministry of Information Industry), has introduced six major preparations and measures of China information industry to meet challenges of China's entry into WTO at the conference "Opportuuities and Challenges of the Information Industry" on 5th Anniversary of China's entry into WTO on 11th Dec, 2006, which are stated as follows:…… 展开更多
关键词 WTO MII prepares six major measures meet challenges of China’s entry into WTO
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不同根管冲洗针头对S形弯曲根管冲洗效果的影响
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作者 汤雨牧 陆乐 +1 位作者 许可 陈於茂 《口腔医学研究》 CAS CSCD 北大核心 2023年第1期32-36,共5页
目的:比较临床常用的2种冲洗针头对S形弯曲根管冲洗效果的影响。方法:采用80个树脂模拟弯曲S形根管,随机分成两组:IrriFlex组(A组)和NaviTip FX组(B组),分别预备至25^(#)0.06锥度和30^(#)0.04锥度各40个。根据根管冲洗针头、冲洗位置和... 目的:比较临床常用的2种冲洗针头对S形弯曲根管冲洗效果的影响。方法:采用80个树脂模拟弯曲S形根管,随机分成两组:IrriFlex组(A组)和NaviTip FX组(B组),分别预备至25^(#)0.06锥度和30^(#)0.04锥度各40个。根据根管冲洗针头、冲洗位置和预备形态分为A1组(IrriFlex,最大冲洗深度,25^(#)0.06锥度)、B1组(NaviTip FX,最大冲洗深度,25^(#)0.06锥度)、A2组(IrriFlex,最大冲洗深度,30^(#)0.04锥度)、B2组(NaviTip FX,最大冲洗深度,30^(#)0.04锥度)、A3组(IrriFlex,距根尖孔4 mm,25^(#)0.06锥度)、B3组(NaviTip FX,距根尖孔4 mm,25^(#)0.06锥度)、A4组(IrriFlex,距根尖孔4 mm,30^(#)0.04锥度)、B4组(NaviTip FX,距根尖孔4 mm,30^(#)0.04锥度),每组10个样本。先将1 mL亚甲蓝染色剂匀速注入树脂根管内,每根管使用3 mL 3%NaClO溶液匀速冲洗。在针头进入根管但尚未注射亚甲蓝时和注射亚甲蓝并冲洗完成后,使用牙科显微镜分别拍照,测量针头到根尖孔的距离及根尖部残留亚甲蓝的长度。采用SPSS 25.0软件对数据进行统计学分析。结果:在最大冲洗深度进行冲洗时,IrriFlex组均较NaviTip FX组深入距离根尖孔更近的位置(P<0.001),根尖部残余亚甲蓝的长度均显著减短(P<0.001);IrriFlex组中,两种终末预备号数对冲洗效果无显著影响(P>0.05),而NaviTip FX组中,25^(#)0.06锥度较30^(#)0.04锥度残余亚甲蓝的长度稍短(P<0.05)。当距根尖孔4 mm进行冲洗时,IrriFlex组与NaviTip FX组残留亚甲蓝长度无显著差异(P>0.05),25^(#)0.06锥度亚组较30^(#)0.04锥度亚组残余亚甲蓝的长度稍短(P<0.05)。结论:S形弯曲根管中,IrriFlex较NaviTip FX更有利于深入根管内进行冲洗。在选择使用NaviTip FX时,可考虑适当加大根管锥度以达到更好的冲洗效果。 展开更多
关键词 根管冲洗 s形弯曲根管 根管预备形态 NaviTip FX IrriFlex
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基于B/S架构的选煤厂智能综合管控系统设计
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作者 郭艳雄 陈宇鹏 《选煤技术》 CAS 2023年第3期88-93,共6页
选煤厂智能化建设是煤炭企业高质量发展的重要环节之一。为促进新一代信息技术在选煤生产管理过程中的深入融合,改善因选煤工艺系统复杂、各系统数据相对分散、分析评价功能缺少造成的各系统相关数据处理难度大和系统安全等问题,提升传... 选煤厂智能化建设是煤炭企业高质量发展的重要环节之一。为促进新一代信息技术在选煤生产管理过程中的深入融合,改善因选煤工艺系统复杂、各系统数据相对分散、分析评价功能缺少造成的各系统相关数据处理难度大和系统安全等问题,提升传统选煤厂选煤质量和选煤效率,基于B/S架构,并结合张家峁选煤厂综合管控需求和业务流程,将选煤生产涉及的各工艺系统进行数据关联与深度融合,设计开发了相关功能模块和系统架构,实现了控制指令通过浏览器页面下发、数据分析、报告管理、综合查询等多类功能。运行结果表明:该系统具备多端支持、组态灵活、协议支持广泛和可视化高效展示等特点,其性能和可扩展性等方面完全实现了传统选煤厂监测监控智能化升级预期目标,全面提升了选煤厂的生产过程管控能力。 展开更多
关键词 选煤厂智能化 选煤厂智能综合管控系统 B/s架构 智能化升级 生产过程管控
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(2S,3S)-3-N-叔丁氧羰基-1,2-环氧基-4-苯基丁烷的合成工艺优化
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作者 孙凤书 《当代化工研究》 CAS 2023年第24期159-161,共3页
(2S,3S)-3-N-叔丁氧羰基-1,2-环氧基-4-苯基丁烷是多种HIV蛋白抑制剂的重要合成切块。本研究针对这个重要中间体的合成工艺进行了优化。整个工艺最关键的步骤为用N,N'-羰基二咪唑为活化试剂,一锅两步法直接合成亚砜叶立德中间体(3)... (2S,3S)-3-N-叔丁氧羰基-1,2-环氧基-4-苯基丁烷是多种HIV蛋白抑制剂的重要合成切块。本研究针对这个重要中间体的合成工艺进行了优化。整个工艺最关键的步骤为用N,N'-羰基二咪唑为活化试剂,一锅两步法直接合成亚砜叶立德中间体(3),避免了活性酰胺中间体(2)的纯化。本研究对还原反应也进行了工艺优化。优化后的工艺共五步,总收率达到43.2%。 展开更多
关键词 (2s 3s)-3-N-叔丁氧羰基-1 2-环氧基-4-苯基丁烷 合成切块 亚砜叶立德 合成工艺优化
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S-腺苷甲硫氨酸研究进展 被引量:27
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作者 余志良 杨晟 +1 位作者 蔡谨 袁中一 《中国医药工业杂志》 CAS CSCD 北大核心 2003年第1期49-52,共4页
综述一种重要代谢中间物质 S-腺苷甲硫氨酸的体内代谢功能、制备、稳定化研究和临床应用进展。
关键词 s-腺苷甲硫氨酸 研究进展 代谢 制备 稳定化 生物合成
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碱催化降解法制备抗癌活性化合物20(S)-原人参二醇 被引量:20
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作者 李绪文 金永日 +2 位作者 桂明玉 张寒琦 张龙清 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2006年第3期478-481,共4页
通过碱催化降解制备了与植物体内结构一致且具有抗癌活性的人参皂苷元20(S)原人参二醇,并对其进行分离及结构表征.将西洋参茎叶总皂苷和强碱溶于高沸点有机溶剂中,在常压和高温条件下进行降解.通过正交试验确定了制备20(S)原人参二醇的... 通过碱催化降解制备了与植物体内结构一致且具有抗癌活性的人参皂苷元20(S)原人参二醇,并对其进行分离及结构表征.将西洋参茎叶总皂苷和强碱溶于高沸点有机溶剂中,在常压和高温条件下进行降解.通过正交试验确定了制备20(S)原人参二醇的最佳降解条件,并将降解物经萃取、柱层析及重结晶等方法分离得到20(S)原人参二醇.按西洋参茎叶总皂苷计,20(S)原人参二醇产率为5.01%,纯度为98.56%.通过理化性质和光谱分析可确认该化合物为20(S)原人参二醇.所制备的20(S)原人参二醇具有产率和纯度高及成本低等特点. 展开更多
关键词 20(s)-原人参二醇 制备 催化 降解 抗癌
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S-腺苷-L-蛋氨酸的分离纯化及其稳定产品的制备 被引量:8
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作者 刘惠 吴坚平 +1 位作者 林建平 岑沛霖 《中国生化药物杂志》 CAS CSCD 2002年第6期284-287,共4页
目的 从酵母萃取液中分离纯化S-腺苷-L-蛋氨酸(SAM)并制备其稳定的盐产品。方法 以苦味酸作为选择性沉淀剂,结合有机溶剂结晶方法沉淀SAM盐产品。结果 确定了影响各步得率的关键因素和最适条件。结论 硫酸盐的制备得率(从酵母到成品)可... 目的 从酵母萃取液中分离纯化S-腺苷-L-蛋氨酸(SAM)并制备其稳定的盐产品。方法 以苦味酸作为选择性沉淀剂,结合有机溶剂结晶方法沉淀SAM盐产品。结果 确定了影响各步得率的关键因素和最适条件。结论 硫酸盐的制备得率(从酵母到成品)可达60%以上,而硫酸、对甲苯磺酸双盐的得率可达50%以上。 展开更多
关键词 s—腺苷—L—蛋氨酸 分离 纯化 盐产品 制备
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S基因在甘蓝EDFs上的高分辨率荧光原位杂交定位(英文) 被引量:5
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作者 杨昆 漆红艳 +1 位作者 朱利泉 王小佳 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2006年第3期277-284,共8页
植物细胞壁及细胞质的存在和植物染色体所具有的高浓缩特性,限制高效率原位杂交定位在植物细胞内的进行。针对小型染色体芸薹属植物采用常规方法DNA制备纤维的效果不佳的特点,新建制备方法:利用减数分裂前期的染色体为材料, 在硅化的玻... 植物细胞壁及细胞质的存在和植物染色体所具有的高浓缩特性,限制高效率原位杂交定位在植物细胞内的进行。针对小型染色体芸薹属植物采用常规方法DNA制备纤维的效果不佳的特点,新建制备方法:利用减数分裂前期的染色体为材料, 在硅化的玻片上先后通过蛋白酶解和乙醇:乙酸(3:1)的适当处理,采用移动界面法制备EDFs。制备的EDFs比未经伸长处理的染色体在经向和横向方面分别取得较高程度的伸长与膨胀,长度可达到89-257 gm,比相应地中期染色体增长30-107倍, 分辨率可达42.8-53.0 kb。利用SRK和SCR两种探针同时在甘蓝粗线期染色体和EDFs上进行了原位杂交,首次鉴定了S基因座在其单倍体基因组中单拷贝性。在杂交信号检测中尽管未经过信号放大,但仍然可以观察到清晰的绿色信号;经荧光显微镜观察,在单一的EDF上发现两个相距1 μm的SCR和SRK的信号点,由此得出局部分辨率为4 kb的最高伸长度。 展开更多
关键词 空间分辨率 EDFs制备 s基因库 移动界面 EDF-荧光原位杂交 s基因定位 杂交图谱数量分析
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(S)-(+)-2-氨基丙醇的KBH_4还原合成法 被引量:7
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作者 杨运旭 敬永生 《中国医药工业杂志》 CAS CSCD 北大核心 2003年第2期65-66,共2页
S)-(+)-2-Amino-1-propanol, the key chiral intermediate of levofloxacin, was preparation from L-2-aminopropionic acid by methyl esterification, and then direct reduction by KBH 4 without purification with an overall yi... S)-(+)-2-Amino-1-propanol, the key chiral intermediate of levofloxacin, was preparation from L-2-aminopropionic acid by methyl esterification, and then direct reduction by KBH 4 without purification with an overall yield of 70%. 展开更多
关键词 氨基丙醇 KBH4 还原 合成法 左氟沙星 中间体
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(R,S)-2-氨基丙醇的制备 被引量:3
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作者 蒋锦 王玉成 郭慧元 《中国医药工业杂志》 CAS CSCD 北大核心 2006年第1期8-9,共2页
氯丙酮经乙酸基化、碱性水解、Raney Ni催化还原胺化得到(R,S)-2-氨基丙醇,总收率44%。
关键词 (R s)-2-氨基丙醇 氧氟沙星 中间体 制备 收率
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