壳聚糖固定化AS1．398中性蛋白酶稳定性的研究

对以壳聚糖为载体,由戊二醛作交联剂。制备的固定化ＡＳ１．３９８中性蛋白酶的稳定性进行了研究。实验结果表明,固定化ＡＳ１．３９８中性蛋白酶对热、乙醇、尿素以及ｐＨ值的稳定性均有明显的提高。     

High-frequency embryogenesis inBrassica campestris microspore culture

Microspore culture is a very important and useful tool in plant breeding for haploid production and has been developed for many years.Brassica campestris (Brassica rapa L. ssp.oleifera) is an important oilseed crop, but it is relatively recalcitrant in tissue culture including microspore culture. The microspore culture in our laboratory is based on the Canadian protocol. Thirty genotypes ofB. campestris were included in this study; twenty produced embryos. The highest yield was 5930 embryos per 100 buds from Canadian genotype Cv-2, this result was one of the best that had been reported in microspore culture inB. campestris. The buds measuring 2.0 mm to 3.9 mm in length responded best to produce embryos, the optimum timing for microspore culture was confirmed to be during the mid-late to very-late uninucleate stage. The buds could be removed from either the main raceme or lateral racemes. Activated charcoal (150 mg l^-1) was added to the liquid NLN medium, it promoted embryogenesis significantly; embryo development was faster and the embryo yield was significantly higher than those cultures without activated charcoal. The donor plant condition was considered an important factor influencing embryogenesis; older donor plants (older than five weeks) and a cold treatment are recommended.     

13C MAS NMR studies of crystalline cholesterol and lipid mixtures modeling atherosclerotic plaques.

Cholesterol and cholesteryl esters are the predominant lipids of atherosclerotic plaques. To provide fundamental data for the quantitative study of plaque lipids in situ, crystalline cholesterol (CHOL) and CHOL/cholesteryl ester (CE) mixtures with other lipids were studied by solid-state nuclear magnetic resonance with magic-angle-sample spinning. Highly distinctive spectra for three different crystalline structures of CHOL were obtained. When CHOL crystals were mixed with isotropic CE oil, solubilized CHOL (approximately 13 mol % CHOL) was detected by characteristic resonances such as C5, C6, and C3; the excess crystalline CHOL (either anhydrous or monohydrate) remained in its original crystalline structure, without being affected by the coexisting CE. By use of 13C-enriched CHOL, the solubility of CHOL in the CE liquid-crystalline phase (approximately 8 mol %) was measured. When phosphatidylcholine was hydrated in presence of CHOL and CE, magic-angle-sampling nuclear magnetic resonance revealed liquid-crystalline CHOL/phosphatidylcholine multilayers with approximately an equal molar ratio of CHOL/phosphatidylcholine. Excess CHOL existed in the monohydrate crystalline form, and CE in separate oil or crystalline phases, depending on the temperature. The magic-angle-sampling nuclear magnetic resonance protocol for identifying different lipid phases was applied to intact (ex vivo) atherosclerotic plaques of cholesterol-fed rabbits. Liquid, liquid-crystalline, and solid phases of CE were characterized.     

豌豆外源凝集素基因的克隆及序列分析

从豌豆幼叶分离基因组ＤＮＡ,设计特异引物,用聚合酶链式反应方法扩增出豌豆外源凝集素基因并克隆到Ｅ．ｃｏｌｉ质粒ｐＢｌｕｅｓｃｒｉｐｔＳＫ（＋）的ＥｃｏＲＶ位点。进一步亚克隆至ｐＵＣ１９。序列分析表明,克隆到的片段大小为８３２ｂｐ,包含了豌豆外源凝集素基因完整的编码序列。该基因无内含子,同报道的已知序列相比,其核苷酸序列及推测的氨基酸序列的同源率分别为９９．６％和９８．９％。     

中药凌霄花的药理学考察

实验结果表明,凌霄花对离体猪冠状动脉条具有抑制收缩的作用;对大鼠血栓形成有抑制作用;能加快红细胞电泳,增加红细胞电泳率,使血液红细胞处于分散状态;对离体孕子宫能显著增强收缩活性,增加收缩频率及增强收缩强度。以上结果可初步说明,凌霄花行血去瘀的作用及其“孕妇慎用”的合理性。凌霄花的３种混淆品（白泡桐花,毛泡桐花,兰考泡桐花）的药理作用与凌霄花不同,故不能作凌霄花使用。     

羊草草地枯枝落叶中N,P,K变化动态

羊草草地枯枝落叶中Ｎ、Ｐ、Ｋ变化动态郭继勋,祝廷成（东北师范大学国家草地生态工程实验室,长春１３００２４）ＤｙｎａｍｉｃｓｏｆＮ,ＰａｎｄＫｉｎｌｉｔｔｅｒｓｏｎＡｎｅｕｒｏｌｏｐｉｄｉｕｍｃｈｉｎｅｎｓｅｇｒａｓｓｌａｎｄ．￥ＧｕｏＪｉｘｕｎａｎｄ...     

中药凌霄花的研究进展

本文对中药凌霄花的研究进展进行了综述,包括生药学研究、化学成分研究、药理学研究及临床应用。