酪氨酸羟化酶基因载体－pCMVTH 质粒的构建及在大鼠骨骼肌内的表达

为用转基因方法治疗巴金森氏病大鼠模型,本研究采用分子克隆技术,将合成多巴胺的关键酶－酪氨酸羟化酶（ＴＨ）的基因,克隆进入以巨细胞病毒ＣＭＶ为启动子的载体质粒内,经限制性内切酶定位分析证实该重组的ＤＮＡ质粒的可靠性。携带ＴＨ基因的ＰＣＭＶＴＨ质粒以ＬＩＰＯ－ＦＥＣＴＩＮ介导,在培养的原代骨骼肌细胞中高效表达。本研究为进一步用转基因的细胞植入脑内以治疗巴金森氏病打下一定基础。     

我国盖蛛属1新纪录种（蜘蛛目：皿蛛科）

记述采自我国云南省勐腊的盖蛛属１新纪录种－鹤嘴盖蛛Ｎｅｒｉｅｎｅｍａｃｅｌｌａ（Ｔｈｏｒｅｌｌ．１８９８）。     

混合氨基酸含量测定新方法

介绍用交流示波极谱滴定法测混合氨基酸的含量。在ＫＣｌ底液中,利用ＨＣＨＯ将－ＮＨ２封闭,用ＫＯＨ标准液滴定,ＨＣＨＯ同时做指示剂,以极谱图形的敏锐变化指示终点的到过,测定结果准确。     

不同月龄婴儿接种DTP后血清中百日咳抗体水平的观测

本文对比观察了２１３例２月龄、３月龄婴儿接种ＤＴＰ后百日咳抗体水平的变化,探讨了母传抗体对免后抗体增长的影响。结果表明２月龄、３月龄婴儿ＤＴＰ免疫后１个月和３个月血清中百日咳抗体达保护水平的百分率无显著性差异（ｘ￣２＝０．０３６,ｐ＞０．９;ｘ￣２＝０．３２７,ｐ＞０．５）,免后１个月抗体ＧＭＴ无显著性差异（ｔ＝０．１７,ｐ＞０．５）,免后３个月抗体ＧＭＴ３月龄组高于２月龄组（ｔ＝２．２２,ｐ＜０．０５）。我们还发现免前抗体水平与免后１个月ＧＭＴ虽有负相关（ｒ＝—０,７５４）的倾向,但总体上对抑制免后抗体应答不明显,因而建议将儿童ＤＴＰ基础免疫的起始月龄提前至２月龄进行。     

紫外激光消融过程的等效模型研究

本文引用等效模型,对激光消融过程进行了推导与计算,和实验结果比较表明,所得公式与实验结果能较好相符,可用于描述紫外激光消融过程。     

南瓜果肉色素的提取及稳定性的研究

本文研究了从南瓜果肉中提取色素的方法,并对它的光、热、酸、碱稳定性进行了研究,发现其性质较稳定,且原料来源广泛,提取工艺简单,着色效果好,是食品、医药、化妆品等领域的理想添加剂。     

温度对黄粉虫成虫繁殖的影响

黄粉虫是多种小型经济动物的常用优良饵料,本试验在20.1℃,24.0℃、28.5℃、31.7℃和36.5五种恒温下饲养该成虫结果,成虫寿命平均分别为63.0、54.2、38.8、38.0和26.1天;每雌平均产卵量则分别为200.3、207.3、122.3、115.8和81.2粒,成虫平均生产1g卵消耗麸皮量分别为2.66、2.00、2.19、2.14和4.15g。结果说明人工繁殖黄粉虫的成虫期温度以24℃为最适宜。     

旋扭山绿豆根瘤菌MXDI6菌株氢酶诱导表达

在自生异养条件下,旋扭山绿豆根瘤菌ＭＸＤＩ６菌株的氢酶诱导表达受气相、ｐＨ值、镍等因子影响：氢酶表达的最适氧浓度为４％,最适氢浓度为１５％,二氧化碳没有明显影响;氢酶表达的ｐＨ值以５．０—６．０为宜;０．５μｍｏｌ／ＬＮｉＣｌ２明显促进吸氢活性,但镍浓度大于１μｍｏｌ／Ｌ则抑制吸氢活性．     

Ultrastructure of the spermatozoa and eggs of the ocean pout (Macrozoarces americanus L.), an internally fertilizing marine fish

Ultrastructure of sperm and eggs of the ocean pout (Macrozoarces americanus L.), an internally fertilizing marine teleost, was examined by scanning and transmission electron microscopy. The results showed that the sperm do not have an acrosome but have a very long mid-piece (one to two times the sperm head length) containing numerous well-developed elongated mitochondria. The sperm also have two tails (is biflagellate) each consisting of nine peripheral and one central pair (9 ± 2) of microtubules. This long mid-piece and the biflagellate nature of the sperm appear to be associated with the long life-span of the sperm and with sperm dispersal in the ovary to fertilize the eggs internally. The ocean pout eggs are enveloped by a porous chorionic membrane similar to that found in other teleosts but have two micropyles, a condition likely related to a mechanism of egg fertilization which increases the egg fertlity in the presence of low sperm numbers. Following insemination, some biochemically undefined excretions appeared on the surface of fertilized eggs and led to the acquisition of adherent capability of the eggs which formed a tightly associated egg mass in sea water. © 1995 wiley-Liss, Inc.     

Kinetics of the Competitive Degradation of Deoxyribose and Other Molecules by Hydroxyl Radicals Produced by the Fenton Reaction in the Presence of Ascorbic Acid

The competition method in which the Fenton reaction is employed as an OH radical generator and deoxyribose as a detecting molecule, has been used to determine the rate constants for reactions of the OH radical with its scavengers. Nonlinear competition plots were obtained for those scavengers which reacted with the Fenton reagents (Fe²⁺ or H₂O₂). Ascorbic acid is believed to overcome this problem. We have investigated the kinetics of deoxyribose degradation by -OH radicals generated by the Fenton reaction in the presence of ascorbic acid, and observed that the inclusion of ascorbic acid in the Fenton system greatly increased the rate of OH radical generation. As a result, the interaction between some scavengers and the Fenton reagents became negligeable and linear competition plots of A7A vs scavenger concentrations were obtained. The effects of experimental conditions such as, the concentrations of ascorbic acid, deoxyribose, H₂O₂ and Fe²⁺-EDTA, the EDTA/Fe²⁺ ratio as well as the incubation time, on the deoxyribose degradation and the determination of the rate constant for mercaptoethanol chosen as a reference compound were studied. The small standard error, (6.76± 0.21) ±' 10⁹M^-1s^-1 observed for the rate constant values for mercaptoethanol determined under 13 different experimental conditions, indicates the latter did not influence the rate constant determination. This is in fact assured by introducing a term, k_x, into the kinetic equation. This term represents the rate of-OH reactions with other reagents such as ascorbic acid, Fe²⁺-EDTA, H₂O₂ etc. The agreement of the rate constants obtained in this work with that determined by pulse radiolysis techniques for cysteine, thiourea and many other scavengers, suggests that this simple competition method is applicable to a wide range of compounds, including those which react with the Fenton reagents and those whose solubility in water is low.