植物资源与化学数据库系统（DPRC）的功能与应用

由中国科学院昆植物研究所和云南省机械研究设计院的植物资源化学数据库系统是一个将植物资源,植物化学成分及化学结构的多种信息、数据和图象融为一体的、开和式多功能软件系统、,包括植资源检索系统、植物化学成分检索系统及天然产物化学结构检索系统等三个子系统。     

人胎胸腺细胞的异质性荧光及其与T淋巴细胞分化阶段关系的形态学研究

以７６９０－Ｘｕ荧光染色法结合ＷｕＴ３、ＷｕＴ４、ＷｕＴ８致敏红细胞花环实验观察经胸腺细胞分层液分离所得高密度亚群和低密度亚群人胎胸腺细胞的异质性荧光及其膜分化抗原ＣＤ３、ＣＤ４、ＣＤ８的表达。结果表明：不同胎龄胎儿胸腺细胞悬液呈现相似形态和相似分布特征的８种异质性荧光的细胞,其中,墨黑核细胞和桔红核细胞分布于两密度亚群,表型为ＣＤ３－ＣＤ４－ＣＤ８－;少数深蓝核和蓝核细胞分布于低密度亚群．表型为ＣＤ３＋,属成熟的胸腺细胞;大多数深蓝核和蓝核细胞、灰蓝核细胞、灰黄核细胞及部分淡桔黄核细胞分布于高密度亚群,表型为ＣＤ３－、ＣＤ４＋、ＣＤ８＋,为处于中间发育阶段的胸腺细胞。推测这些细胞胞核由深蓝、蓝、灰蓝、灰黄到淡桔黄的荧光光谱的偏移可能与中间发育阶段所发生的生物及理化变化有关。     

鳗鱼肌肉的氨基酸及营养价值

通过对优质食用鱼类—鳗鱼肌肉的氨基酸进行测定证实,鳗鱼较之其它鱼类是一种营养价值更高、滋味更鲜美的鱼类。并且,根据结果氨基酸组成比例,可为鳗鱼的人工饲养等方面的研究提供理论依据。     

用中性红标记酵母原生质体初探

用２％蜗牛酶处理酵母细胞６０分钟,啤酒酵母Ｙ２９的原生质体形成率为９０％,再生率为９．５％;糖化酵母ＩＢ的原生质体形成率为８６％,再生率为１２％。用５００ｐｐｍ中性红染液对Ｙ２９菌株的整细胞和原生质体染色１５分钟,细胞的着色率为８４％,存活率为１２％,而原生质体的着色率为７５％,再生率为６．４％,经染色后的原生质体体积缩小,在交变电场中排队所需的场强电降低。     

Inhibition of rabbit sperm acrosomal enzymes by gossypol

The effect of gossypol on the activities of 10 acrosomal enzymes of the rabbit sperm was evaluated. Acrosin, Azocoll proteinase, neuraminidase, and arylsulfatase were significantly inhibited or completely inactivated by 12–76 μM gossypol. Hyaluronidase, β-glucuronidase, and acid phosphatase were inhibited only at a higher concentration of gossypol (380 μM). Phospholipase C, alkaline phosphatase, and β-N-Acetyl glucosaminidase were not inhibited even at 380 μM gossypol. Gossypol was found to be a noncompetitive inhibitor of arylsulfatase with a Ki of 120 μM. The inhibition was reversible and dose-dependent. As the acrosomal enzymes were more sensitive to the inhibition by gossypol compared to sperm enzymes involved in glycolysis or energy production, these assays may serve as a more reliable indicator for monitoring the occurence of gossypol-induced sterility. © 1995 Wiley-Liss, Inc.     

家鸡和原鸡的线粒体DNA多态性比较

本文运用１１种限制性内切酶分析了家鸡（茶花鸡、尼西鸡、大理漾濞黄鸡）和原鸡共１０只个体的线粒体ＤＮＡ限制性片段长度多态性（ＲＦＬＰ）,平均每个个检测到的片段为４０条左右。但仅发现３种变异的限制性片制性格局,即ＳｔｕＩ－Ｂ,Ｅｃａ－Ｉ－ｂ和ＲＩ－Ｂ．其中ＳｔｕＩ－Ｂ和ＳｃａＩ－Ｂ为首次报道,而且均为原鸡所物有,ＥｃｏＲＩ－Ｂ则为大理漾濞黄鸡所特有。茶花鸡和尼西鸡拥有完全相同的限制性格局。经过计算,原     

Multiple genotypes of mitochondrial DNA within a horse population from a small region in Yunnan province of China

mtDNA genotypes of six domestic horses (three adult short horses whose heights are under 1 m and three common domestic horses) from a small region of 15 km² in Malipo county of Yunnan province of China were investigated by the technique of restriction fragment length polymorphism (RFLP) with 16 restriction endonucleases which recognize 6-bp sequences. An average of 56 fragments for an individual was obtained. Unlike other domestic animals, this population of horses exhibits high mtDNA genetic diversity. Each of the six horses has a specific mtDNA genotype showing a pattern of multiple maternal origins, as suggested by fossil and literature records. We think the population of horses is an amazing seed-resource pool of horses and hence deserves to be paid more attention from the view of conservation genetics. However, it is also remarkable that we did not find any typical mtDNA genetic markers which would discriminate between short horses and common domestic horses.     

Intraspecific cleaning behaviour in Cyprinus carpio in aquaria

Intraspecific cleaning behaviour of diseased juvenile Cyprinus carpio L, in experimental tanks in Wuxi, China has been observed and is described.     

A Suppressor of a Mating-Type Limited Zygotic Lethal Allele Also Suppresses Uniparental Chloroplast Gene Transmission in Chlamydomonas Monoica

Uniparental inheritance of Chlamydomonas chloroplast genes is thought to involve modification of maternal (mt(+)) chloroplast genomes to protect against a nuclease that is activated after gamete fusion. The mating-type limited mtl-1 mutant strain of Chlamydomonas monoica is unable to protect mt(+)-derived chloroplast DNA. Zygotes homozygous for mtl-1 lose all chloroplast DNA and fail to germinate. We have selected for suppression of this zygote-specific lethality, and have obtained 20 mutant strains that produce viable homozygotes despite the continued presence of the mtl-1 allele. Genetic analysis indicates that the suppressor mutations are all recessive alleles at a single locus (sup-1) which is unlinked to mtl-1. Crosses between sup-1 strains carrying distinctive chloroplast antibiotic resistance markers also show predominantly biparental chloroplast gene transmission. Chloroplast nucleoids of both parental origins (stained with the DNA-specific fluorochrome, DAPI) are retained in the zygotes homozygous for sup-1. The data are compatible with the idea that the sup-1 (suppressor of uniparental inheritance) locus may encode a chloroplast DNA nuclease that is expressed from both parental genomes.     

Phylogenetic relationships among eutherian orders estimated from inferred sequences of mitochondrial proteins: Instability of a tree based on a single gene

The phylogenetic relationships among Primates (human), Artiodactyla (cow), Cetacea (whale), Carnivora (seal), and Rodentia (mouse and rat) were estimated from the inferred amino acid sequences of the mitochondrial genomes using Marsupialia (opossum), Aves (chicken), and Amphibia (Xenopus) as an outgroup. The overall evidence of the maximum likelihood analysis suggests that Rodentia is an outgroup to the other four eutherian orders and that Cetacea and Artiodactyla form a clade with Carnivora as a sister taxon irrespective of the assumed model for amino acid substitutions. Although there remains an uncertainty concerning the relation among Artiodactyla, Cetacea, and Carnivora, the existence of a clade formed by these three orders and the outgroup status of Rodentia to the other eutherian orders seems to be firmly established. However, analyses of individual genes do not necessarily conform to this conclusion, and some of the genes reject the putatively correct tree with nearly 5% significance. Although this discrepancy can be due to convergent or parallel evolution in the specific genes, it was pointed out that, even without a particular reason, such a discrepancy can occur in 5% of the cases if the branching among the orders in question occurred within a short period. Due to uncertainty about the assumed model underlying the phylogenetic inference, this can occur even more frequently. This demonstrates the importance of analyzing enough sequences to avoid the danger of concluding an erroneous tree.