一种具有纤溶活性的枯草杆菌蛋白激酶的研究──Ⅰ高产酶菌株的筛选与鉴定

本文主要阐述了一种具有纤溶活性的枯草杆菌（Ｂａｃｉｌｌｕｓｓｕｂｔｉｌｉｓ）蛋白激酶产生菌株的筛选与鉴定的研究结果。作者从初筛的１２株Ｂａｃｉｌｌｕｓｓｕｂｌｉｌｉｓ菌中,通过对固体发酵和液体发酵所产生的枯草杆菌蛋白激酶,用琼脂糖－纤维蛋白平板法测其活性,经比较不同菌株的活性,筛选出两株高产酶菌株：Ｂ．ｓｕｂｔｉｌｉｓＨＷ—１２和Ｂ．ｓｕｂｔｉｌｉｓＨＷ—３。同时对菌体和菌落形态特点、生理生化反应进行了鉴定,认为Ｂ．ＳｕｂｔｉｌｉｓＨＷ－１２菌株可用来做为发酵生产该酶的菌种。     

灵芝对小鼠空间分辨学习与记忆的影响

本文用Y-型迷宫法测试小鼠空间分辨行为。实验结果表明,每日ig灵芝2.58/kg共7d,有明显促进学习的作用。每日ig灵芝2.5g/kg共7d或ig灵芝5g/kg共7d都能显著地拮坑东莨菪碱所致学习障碍的作用。此外,学习训练后立即ig灵芝2.5g/kg或ig灵芝5g/kg也有明显地改善东莨菪碱损害记忆巩固的作用。     

羊角椒辣味物质成份分析

用紫外光谱法、红外光谱法和高效液相色谱法分析羊角椒中辣味物质纯度与组成,表明辣味物质由辣椒素、二氢辣椒素和降二氢辣椒素组成。     

固定化酵母细胞生产1,6-二磷酸果糖研究

本文研究了固定化酵母细胞制备果糖1,6二磷酸(FDP)的方法及其生产。用卡拉胶包埋方法固定化酿酒酵母(Sacchromyces cerevisae),对含葡萄糖1.0M,磷酸盐0.8M的糖磷液,pH6.5,在37℃下进行磷酸化反应。反复分批转化20天以上,可达到平均产FDPH_427.58mg/ml,最高为59.94mg/ml。用100ml固定化细胞生物反应器连续运转309h,稀释速率D=0.097h~(-1),平均产FDPH_4 21.51mg/ml。20L反应器连续运转,生产能力达到1.7g/h.L。用层析方法制备FDPNa_3结晶粉,提取收率为72.08％,制备质量达到或超过了国内外同类产品的质量要求。     

低能量He—Ne激光血管内照射治疗银屑病21例报告

21例寻常型银屑病患者,经用He－Ne激光血管内照射,功率3．5－5mw,每日照射一次,每次1小时,10次一疗程,同时伴用vitc2givq．d及鼻吸氧,二疗程间休息4－7天,经5－35次治疗,近期疗效：近期痊愈5例（23．81％）,显效6例（28．57％）,好转10例（47．62％）,总有效率100％,复发1例（4．76％）。     

A block to efficient replication of simian immunodeficiency virus in C8166 cells can be overcome by duplication of the NF-κB binding site

Sequence analysis of the acutely lethal pbj14 strain of simian immunodeficiency virus (SIVpbj14) clone revealed among other differences from its less pathogenic counterparts a duplication of its binding site for nuclear factor kappa B (NF-B) in its long terminal repeats (LTR). We have investigated whether introducing a similar duplication into the pathogenic molecular clone SIVmac239 would alter its biological properties. We compared an SIV which possessed 2 NF-B sites to the wild type, a single NF-B site virus, with respect to its ability to replicate in vitro in established CD4+ T cell lines, primary peripheral blood mononuclear cells (PBMCs), and primary alveolar macrophages. The virus containing 2 NF-B sites exhibited no apparent difference from wild type in established cell lines 174×CEM, MT-2 and MT-4, or in primary PBMC or tissue macrophage cultures. However, the 2 B virus replicated well in the established cell line C8166, while the wild type, 1 B virus replicated very poorly in this cell type, suggesting that duplication of the NF-B site is capable of overcoming a block to efficient replication of SIVmac239 in C8166 cells. Interestingly, Em*, a macrophage tropic SIVmac that differs from SIVmac239 by 9 amino acids in the envelope region yet possesses only one NF-B binding site, also replicates well in C8166. The data suggest that the replication of wild type SIVmac239 is restricted in C8166 cells, but that this restriction can be overcome either by changes in the LTR or by changes in the envelope region.     

高血压病的复合超声心动图研究

现常用于检测高血压病的彩色、脉冲多普勒及二维、M型超声心动图几种方法,各有其优点与不足。本文利用其各自的优点,运用上述复合超声心动图法检测96例高血压病患者及86例正常人,进行了分析研究。认为,此法检诊高血压病是实用、可行的。     

Characterization of phospholipase A2 activation by plasmin in cultured bovine endothelial cells

Treatment of cultured bovine carotid artery endothelial cells with 0.1 µM human plasmin has been reported to induce a receptor-mediated short burst of arachidonate release, which is a pertussis toxin-sensitive and extracellular calcium-dependent reaction. Plasmin-induced calcium influx in cells was significantly inhibited by pretreatment with pertussis toxin, indicating that the former was coupled with a pertussis toxin-sensitive guanosine 5-triphosphate (GTP)-binding protein. Plasmin significantly induced the formation of lysophosphatidylcholine but not lysophosphatidylethanolamine. A cellular phospholipase A₂ with an arachidonyl specificity at the sn-2 position of phosphatidylcholine, which required submicromolar calcium, was identified as a cytosolic phospholipase A₂ by immunoblot analysis. By a cell-free enzyme activity assay and immunoblot analysis, plasmin was found to induce a translocation of the cytosolic phospholipase A₂ from the cytosol to the membrane. Taken together, the results suggest that plasmin bound to its putative receptor and activated a GTP-binding protein coupled to calcium influx channel, followed by translocation and activation of cytosolic phospholipase A₂ in endothelial cells.     

Potential and pitfalls of trying to extend symbiotic interactions of nitrogen-fixing organisms to presently non-nodulated plants,such as rice

It has been a long-standing goal in the field of biological nitrogen fixation to extend nitrogen-fixing symbioses to presently non-nodulated cereal plants, such as rice. A number of researchers have recently described the induction of nodule-like structures on the roots of cereals primarily by rhizobia, in either the presence or absence of plant cell-wall-degrading enzymes or plant hormones. We briefly review this research and discuss the potential problems associated with the introduction of nitrogen-fixing microbes in novel physiological environments, such as rice roots. The results of experiments carried out in China on the induction of nodule-like structures on rice roots by rhizobia are highlighted. In addition, we present preliminary results of a series of experiments designed to repeat and evaluate these results using a variety of microscopic techniques and molecular genetic approaches.     

Two-dimensional crystallization of avidin on biotinylated lipid monolayers.

Two-dimensional crystals of avidin were obtained on mixed lipid monolayers containing biotinylated lipids (N-biotinyl-dipalmitoyl-L-alpha-phosphatidyl ethanolamine and dioleoyl phosphatidyl choline) by specific interaction. Image analysis of electron micrographs of these crystals revealed p2 symmetry with the unit cell parameters a = 66 +/- 2 A, b = 68 +/- 1 A, and gamma = 121 +/- 4 degrees. The projection map showed, at a resolution of about 27 A, that the four subunits within one avidin molecule are separated into two parts. Comparison between avidin and streptavidin reveals that avidin molecule binds to the lipid monolayer in an orientation similar to that of streptavidin.