从红豆杉树皮浸膏中提取紫杉醇初分离工艺的研究

从红豆杉树皮浸膏中高效提取紫杉醇。方法;采用液－液萃取、固相萃取、硅胶柱层析、氧化铝柱层析、薄层层析五种分离方法对紫杉醇进行了初分离。结果：优化的紫杉醇初分离方案为红豆杉树皮提取物先经氧化铝柱,再上固相萃取柱进行分离提取。结论：该工艺分离所得紫杉醇浓度可达４０％以上,紫杉醇的回收率超过１０％。     

东北红豆杉原料中紫杉醇的提取及测定

将磨碎的红豆杉树皮和针叶采用二氯甲烷－甲醇抽提、二氯甲烷－水两相萃取，经间歇过滤、硅藻土涂渍后上硅胶柱色谱分离，再在含水甲醇中结晶，得含量＞９０％的紫杉醇。总产率为干叶重的０．００６％，干树皮重的０．００４％。     

酸性与碱性化合物固相萃取法屏蔽相的特性研究

固相萃取法是一种越来越普遍使用的制备分析样品的重要方法。因为用液－液萃取法产生的废有机溶剂的处理问题越来越多，所以该技术可能具有更重要的意义。作者用放化纯度超过95％的14C标记的普萘洛尔、ICI128436（化学名为［2－（4-嗅－2－氟苄基）－1，2－二氢－1－氧－（1，4-14C）－4-（2，3-二氮杂萘基）乙酸〕和茴香酸研究了Hisep（一种新的固相萃取键合相）的萃取物的特性。实验方法如下：用装有300mg化学物质的SupelcoHisep盒，该相是硅胶支持的，具有疏水网围起来的疏水袋构成的屏蔽相，该结构允许小分析物渗入疏水袋而防止较大…     

紫杉醇、三尖杉宁碱和7-表-10-去乙酰基紫杉醇的分离及7-表-紫杉醇的转化研究

目的 探索从云南红豆杉树皮提取物中分离紫杉醇、三尖杉宁碱和7-表-10-去乙酰基紫杉醇3种纯化合物以及7-表-紫杉醇转化成紫杉醇的高效方法。方法 用乙酸叔丁酯为单漉动相。硅胶为填充柱的正相色谱系统分离。使用碱性氧化铝，在40℃对7-表-紫杉醇进行催化而转化成紫杉醇。结果与结论 分离得到紫杉醇、三尖杉宁碱和7-表-10-去乙酰基紫杉醇3个纯化合物。7-表-紫杉醇转化率可达30％。     

红豆杉浸膏在氧化铝催化下紫杉醇的生成研究

目的 :研究在氧化铝层析初分离红豆杉浸膏中紫杉醇增量的来源。方法 :采用C18 硅胶反相层析、氧化铝层析及硅胶层析等方法对物料进行处理 ,HPLC分析紫杉醇的含量。结果 :紫杉醇增量主要来源于红豆杉浸膏中 7 表 紫杉醇的碱性氧化铝催化下的异构化。结论 :优化 7 表 紫杉醇的异构化条件 ,可以增加 7 表 紫杉醇向紫杉醇的转化。     

X－5树脂固相萃取用于血中安眠镇静类药物快速筛选方法研究

本文详细考查了Ｘ－５树脂固相萃取分离和纯化血中药物所涉及到的各种因素的变化对药物回收率的影响，在此基础上建立了Ｘ－５树脂固相萃取结合毛细管气相色谱筛选血中安眠镇静类药物的方法。     

用三嗪染料修饰吐温80液-固萃取乳酸脱氢酶的研究

利用三嗪类染色Cibacron Blue F3G－A修饰吐温80，与硫酸铵构建染料聚合物－盐的液－固亲和萃取体系，从猪心肌匀桨液中分离纯化乳酸脱氢酶。结果表明，吐温80浓度12％，含染料吐温80为5％；硫酸铵浓度1．81mol/L;pH7．4，匀浆液加入量为体系的1％，吐温80相平均酶活收率93％，纯化倍数9．2。研究了乳酸脱氢酶与吐温80相分离的条件，将吐温80相保温溶解，改变硫酸铵浓度为0．9mol/L，二次成相反萃，盐水相酶活收率90％。实现了酶与聚合物的分离。     

紫杉醇分子印迹聚合物在固相萃取中的吸附和解吸

目的研究紫杉醇分子印迹聚合物在固相萃取中的应用。方法采用分子印迹沉淀合成技术,以紫杉醇为模板分子、甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸为交联剂、偶氮二异丁腈为引发剂,在氯仿与甲苯混合液中合成紫杉醇分子印迹聚合物,并以此为填料进行固相萃取,分离纯化紫杉醇。印迹聚合物对紫杉醇的吸附选择性优化聚合反应条件,通过平衡结合法和Scatchard模型评价聚合物吸附特点,再用固相萃取技术对清洗洗脱方法进行优化,采用实际提取浸膏考察固相萃取柱的可用性。结果甲基丙烯酸和紫杉醇的摩尔比为4∶1,聚合温度为60℃时,分子印迹聚合物(molecularly imprinted polymers,MIPs)对紫杉醇呈现高特异性吸附;印迹吸附符合Scatchard模型,计算MIPs对紫杉醇的最大表观结合点数为3.66 mg·g~(-1),K_d为6.627。结论分子印迹聚合物可以为紫杉醇的分离纯化提供新型选择性富集材料。     

固相萃取—高效液相色谱法测定脑得生片中人参皂甙Rg1的含量

本文建立固相萃取－高效液相色谱法测定脑得生片中人参皂甙Ｒｇ１含量的条件，采用超声振荡和固相萃取提取，色谱柱为Ｓｈｉｍ－ｐａｃｋＣＬＣ－ＯＤＳ，流动相为乙腈－水（３：７），检测波长２１０ｎｍ，平均回收率为（９４．６±２．４６）％，ＲＳＤ为２．４６％。该法适应于脑得生惩中人参皂甙Ｒｇ１的含量测定。     

紫杉醇提取纯化工艺

以云南红豆杉树皮（或树叶）为原料，提取纯化紫杉醇。先经９５％乙醇、二氯甲烷提取，再经硅藻土柱涂渍色谱、硅胶６０中压快速柱色谱分离，收集含紫杉醇－ｃｅｐｈａｌｏｍａｎｎｉｎｅ的组分后以Ｃ_（１８）制备型ＲＰ－ＨＰＬＣ分离，两次结晶后得到紫杉醇无色结晶固体，纯度≥９８．８％，收率为树皮干重的０．０２８％，树叶干重的０．００８８％。     

Degraded and undegraded carrageenans and experimental gastric and duodenal ulceration

The prevention of histamine-induced gastric and duodenal ulceration in the guinea-pig has been examined using a series of undegraded and degraded carrageenans. Undegraded carrageenans were active at lower doses than degraded carrageenans. The high viscosity of the undegraded carrageenans in solution prevented their use in larger doses. Degradation of carrageenan without serious loss of sulphate, gives a product which allows the dose to be increased to an extent that its effect more than offsets the slight loss in activity caused by the degradation. No single feature of carrageenan structure can be related to anti-ulcer activity although degradation, and hence reduction of molecular size, generally reduces activity. Sulphate contents over 30% have little apparent effect on activity; κ-carrageenans were not consistently different in anti-ulcer activity from Λ-carrageenans. This contrasts with the antipeptic activity of carrageenans where κ-carrageenans are less active than their Λ-counter-parts. As with antipeptic activity, the degree of anti-ulcer activity is probably determined by a combination of structural features which includes molecular size and polyanionic properties.     

Affective and Anxiety Disorders and Alcohol and Drug Dependence:

Depression and anxiety frequently coexist in patients with substance use disorders. This clinically-oriented article examiens the relationship between these conditions and emphasizes data showing that substances of abuse can cause signs and symptoms of both depression and anxiety. These substance-related syndromes appear to have a different course and prognosis than uncomplicated, independent anxiety and major depressive disorders, and clinicians should consider the role of alcohol and other drugs in all patients presenting with these complaints. The authors will also outline an approach for diagnosing and managing patients with the combination of a substance use and depressive or anxiety disorder.     

Alcohol and Substance Use and Abuse in Women and Children

No abstract available for this article.     

Glucosidase and fucosidase inhibitors and Advances in nucleosides and nucleotides.

The American Chemical Society Symposium "Glucosidase and fucosidase inhibitors" took place on 1 April 1998 and was organized by Professors Zbigniew J Witczak (UConn, School of Pharmacy, CT, USA), Kuniaki Tatsuta (Waseda University, Tokyo, Japan) and Waldemar Priebe, MD (Anderson Cancer Center, University of Texas, USA). Professor Witczak provided introductory remarks including the status of existing glucosidase inhibitors, and chaired the morning session, which consisted of six lectures. The symposium was well received, and was particularly attractive for those interested in networking, as attendance was about sixty. In addition, some participants and attendees presented posters on the subject during the regular poster session organized by the Division of Carbohydrate Chemistry.