2W Yb-doped double-clad fiber superfluorescent source with 42 nm 3 dB bandwidth

The output spectrum of Yb-doped double-clad fiber superfluorescent source (SFS) is tailored by placing a broadband dichroic mirror in the pump end of conventional single-pass forward configuration, which constitutes double-pass forward configuration. The 3 dB bandwidth is increased from I I to 42 nm. A maximum output SFS power of 2.12 W and a slope efficiency of 43.2% are obtained. The double-clad fiber is 25 in and the pump power is adequate to saturate the fiber as far as the feedback-induced lasing appears. (c) 2004 Elsevier Ltd. All rights reserved.

大蹼铃蟾神经营养因子及其制备方法和其基因

本发明涉及大蹼铃蟾神经营养因子及其制备方法和其基因，属于生物医学领域。其神经营养因子为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由77个氨基酸组成的一种单链多肽，分子量8125.8，等电点8.6，多肽氨基酸全序列一级结构为：AVITGACDRDVQCGSGTCCAASLWSRNIRFCVPLGNNGEECHPASHKVPYNGKRLSSLCPCKSGLTCSKSGEKFQCS。制备方法是收集大蹼铃蟾皮肤分泌物，离心去除沉淀、冷冻干燥后，经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码神经营养因子的基因由447个核苷酸组成，其中编码成熟神经营养因子为第145-375位核苷酸。其基因作为基因工程制备神经营养因子的应用。

Phylogenetic relationships of the macaques (Cercopithecidae : Macaca), inferred from mitochondrial DNA sequences

To study the phylogenetic relationships of the macaques, five gene fragments were sequenced from 40 individuals of eight species: Macaca mulatta, M. cyclopis, M. fascicularis, M. arctoides, M. assamensis, M. thibetana, M. silenus, and M. leonina. In addition, sequences of M. sylvanus were obtained from Genbank. A baboon was used as the outgroup. The phylogenetic trees were constructed using maximum-parsimony and Bayesian methods. Because five gene fragments were from the mitochondrial genome and were inherited as a single entity without recombination, we combined the five genes into a single analysis. The parsimony bootstrap proportions we obtained were higher than those from earlier studies based on the combined mtDNA dataset. Excluding M. arctoides, our results are generally consistent with the classification of Delson (1980). Our phylogenetic analyses agree with earlier studies suggesting that the mitochondrial lineages of M. arctoides share a close evolutionary relationship with the mitochondrial lineages of the fascicularis group of macaques (and M. fascicularis, specifically). M. mulatta (with respect to M. cyclopis), M. assamensis assamensis (with respect to M. thibetana), and M. leonina (with respect to M. silenus) are paraphyletic based on our analysis of mitochondrial genes.

Evidence of gene conversion in the evolutionary process of the codon 41/42 (-CTTT) mutation causing beta-thalassemia in southern China

The 4-bp deletion (-CTTT) at codon 41/42 (CD41/42) of the human beta-globin gene represents one of the most common beta-thalassemia mutations in East Asia and Southeast Asia, which is historically afflicted with endemic malaria, thus hypothetically evolvi

Two new compounds and anti-HIV active constituents from Illicium verum

Two new compounds named illiverin A (1) and tashironin A (8) were, isolated from the roots of Illicium verum, together with seven known compounds: 4-allyl-2-(3-methylbut-2-enyl)-1,6-methylenedioxybenzene-3-ol (2), illicinole (3), 3-hydroxy-4,5-methylenedi

D77, one benzoic acid derivative, functions as a novel anti-HIV-1 inhibitor targeting the interaction between integrase and cellular LEDGF/p75

Integration of viral-DNA into host chromosome mediated by the viral protein HIV-1 integrase (IN) is an essential step in the HIV-1 life cycle. In this process, Lens epithelium-derived growth factor (LEDGF/p75) is discovered to function as a cellular co-fa

丙型肝炎病毒感染猕猴属三种动物的血清丙氨酸转氨酶动态观察

丙型肝炎病毒感染猕猴属三种动物的血清丙氨酸转氨酶动态观察田保平，夏宁邵，汤权，季维智，杨上川，屠建平，许加福，毕胜利丙型肝炎（ＨｅｐａｔｉｔｉｓＣ）是一种近年来发现的、由丙型肝炎病毒（ＨＣＶ）引起的严重危害人类的传染病。由于大约９０％的输血后肝炎均属...

西南地区社鼠的亚种分化兼二新亚种描记

系统整理了我国西南及其邻近地区的社鼠标本,主成分分析(PC)和判别分析(DA)的结果也表明上述两地的标本都各自形成一个有别于指名亚种的类群,故分别将上述两地的标本订为2新亚种:雅江亚种(N. c. yajianensis subsp.nov.)和德钦亚种(N.c.deqinensis subsp.nov.)。由此确立了西南地区原社鼠指名亚种至少应分为3个亚种。

应激和学习对突触效能的调控机制

简要地介绍了应激、学习对突触可塑性(LTP/LTD)的影响的一些主要实验结果。探讨突触可塑性在神经信息储存中的作用。

苹果绵蚜与苹果绵蚜蚜小蜂种间关系的模拟研究——Ⅰ.两种群生物学的数量特征比较

本研究通过对苹果绵蚜(Eriosoma lanigerum Haus.)和苹果绵蚜蚜小蜂(Aphelinus mali Hald.)的生物学和生态学特性的比较分析,得到如下结论:(1)苹果绵蚜完成一世代的积温要求和发育起点温度均低于苹果绵蚜蚜小蜂,二者的有效积温分别为352.19日度和375.51日度,发育起点温度分别为7.62度和7.95度。因此,苹果绵蚜较其寄生蜂更适合于昆明地区的气候条件;(2)苹果绵蚜种群的增长能力大于苹果绵蚜蚜小蜂,二者的内禀增长率在20℃下分别为0.1390和0.1146,在25℃下分别为0.2647和0.1628。这可能是昆明地区苹果绵蚜蚜小蜂不能控制苹果绵蚜为害的主要原因。

猕猴输精管注射高分子聚合物HFMC的抗生育试验初报

利用一种高分子聚合物HFMC注入输精管, 遇体液即合成有孔隙的固态聚合物 , 附着管壁并缓慢释放适度的H~(+), 以改变精子存活环境, 从而达到猕猴 非阻断性的输精管避孕。实验结果还表明: HFMC对精子具有致死、致畸率高及使 精子活力显著下降的作用, 这些作用随HFMC剂量的增大而加强, 随时间的后移 而逐渐减弱; HFMC对输精管具有可通性及可复性。HFMC有可能成为男性节育较为 理想的一种新型避孕剂。表2参6