小寨子沟自然保护区珍稀濒危植物资源现状

本文利用现代全球定位(GPS)技术和地理信息系统(GIS)手段,对四川省小寨子沟自然保护区内的珍稀濒危植物资源进行了精确定位和详尽地调查,基本掌握其种类、数量、地理分布、濒危状况等信息,并针对目前珍稀濒危植物的受威状况提出保护对策.     

青藏高原白腰雪雀鸣声结构的复杂性

本文以SAS Lab鸟类声谱分析软件对采自青藏高原黑马河、玛多与花石峡、沱沱河的白腰雪雀不同地方种群的鸣叫与鸣唱的复杂性进行了分析 ,发现白腰雪雀的鸣叫相对变化率随着采样量的增加由 0 5 2 2迅速降低到 0 1 2 7和 0 1 1 9,表明其鸣叫声组成中音节类型较少。同时发现其声谱图结构比较简单 ,表现出高度的音节重复并多有谐波的现象。鸣唱结构相对复杂 ,不同鸣唱音节数随鸣唱曲目的增加 ,开始有明显的增加 ,当鸣唱曲目增加到一定值时 ,不同音节数的增加趋于平缓 ,几乎保持稳定 ;野外未发现任何相同的鸣唱型 ,但在不同鸣唱型之间具有不同程度的音节共享现象。依据雷富民等 (2 0 0 3)对鸟类鸣唱多样性和复杂性的评述 ,白腰雪雀鸣唱的结构模式符合“多音节序列不稳定变化型” ,其鸣唱曲目中音节的转换形式为“序列鸣唱”。然而 ,鸣唱模式中音节类型的有限性和鸣唱型的高度多样化表明 :白腰雪雀鸣唱的复杂性不仅体现在鸣唱型内较丰富的音节组成 ,而且更重要的还在于不同鸣唱型间具有多变的音节序列组合形式     

应用反向遗传学技术在哺乳动物细胞中产生甲型流感病毒

在国内首次应用反向遗传学技术将多个质粒共转染哺乳动物细胞,得到了具有活性的甲型流感病毒.采用自行构建的含有polⅠ和polⅡ启动子和终止子序列的pIVV2质粒,将A/PR/8/34(H1N1)流感病毒基因组全部8个RNA节段的cDNA分别克隆到该质粒的两个启动子之间,得到了8个可在真核细胞中复制和表达的质粒.将这8个质粒共转染293T细胞,培养48h后吸取上清液,转接入MDCK细胞中,再经过72h培养,发现在MDCK细胞中有明显的流感样细胞病变产生,测上清病毒血凝滴度为1:10.将MDCK细胞冻融液继续接种鸡胚和MDCK细胞,培养后将鸡胚尿囊液和MDCK细胞冻融上清液进行血凝和血凝抑制实验,证明所得病毒为A/PR/8/34(H1N1).此结果将有助于国内今后对流感疫苗的研究.     

β—连接素在膀胱移行细胞癌中表达的意义

目的 探讨β－连接素（β－ctenin）蛋白的表达及其与膀胱移行细胞癌组织学特征和侵袭的关系。方法 采用免疫组化SP法检测46例膀胱移行细胞癌组织中的β－ctenin的表达。结果 正常膀胱粘膜上皮细胞全部表达β－ctenin,膀胱移行细胞癌中β－ctenin的表达率分别是“＋＋＋”为52．1％（24／46）,“＋＋”为32．6％（15／46）,“＋”O 15．2％（7／46）。侵袭型的膀胱移行细胞癌中β－ctenin表达率是“＋＋＋”为11．1％（1／9）,显著低于乳头状型者（P＜0．01）。结论 β－ctenin的表达与膀胱移行细胞组织学特征及侵袭有相关性,可作为判断肿瘤恶笥肿瘤、侵袭、预后的价值指标。     

一种简易繁殖潜蝇姬小蜂的方法

简要介绍了以蚕豆作为寄主作物,南美斑潜蝇作寄主,在自然条件下利用纱岗笼罩进行潜蝇姬小蜂Diglyphus isaea Walker的人工繁殖方法。     

中华通草蛉卵、幼虫和成虫在麦田分布型的研究

研究了中华通草蛉卵、幼虫和成虫在麦田的分布型,均属聚集分布,分析提出适宜的取样调查方法,即双对象线或棋盘式10点,每点调查1m^2麦株。     

Application of the equilibrium concept to the development of agaric fruit-bodies, with special reference to their straight downward growth in light from below

Equilibrium, a concept of dynamics, is found to be applicable to the phototropic and gravitropic growth in agaric fruit-bodies. The fruit-bodies exposed to light from below grow straight downward without bending upward, and those exposed to light from obliquely below grow first downward and then upward by negative gravitropism. The fruit-bodies exposed to light from above grow upward. Fruit-bodies growing straight downward or upward do not change the direction of growth; they are in ‘equilibria’. The straight downward growth can be regarded as an ‘unstable equilibrium’ having a higher potential, and the straight upward growth as a ‘stable equilibrium’ having a lower potential. The change in the direction of growth can be explained by the change in the potential; the upward bending in fruit-bodies that have grown obliquely downward can be regarded as a ‘transition’ from the unstable equilibrium to the stable one.     

Structure of human holocarboxylase synthetase gene and mutation spectrum of holocarboxylase synthetase deficiency

Holocarboxylase synthetase (HLCS) is an enzyme that catalyzes the incorporation of biotin into apo-carboxylases, and its deficiency causes biotin-responsive multiple carboxylase deficiency. The reported sequences of cDNA for human HLCS from liver, lymphocyte, and KG-1 myeloid cell lines differ at their 5' regions. To elucidate variations of the human HLCS mRNA and longer 5' cDNA ends, we performed screening of the human liver cDNA library and rapid amplification of the cDNA ends (RACE). Our results suggest the existence of three types of HLCS mRNA that start at different exons. The first type starts at exon 1, and the second type starts at exon 3, and both are found in various human tissues. The third type, corresponding to the cDNA from the KG-1 cell, starts at exon 2 of the HLCS gene. Various splicing patterns from exons 3-6 were also observed. None of the variations of cDNA found created a new initiation codon. Mutation screening from exons 6-14, therefore, was sufficient to detect amino acid changes in HLCS in patients. Our direct sequencing strategy for screening mutations in the HLCS gene revealed mutations in five Japanese patients and seven non-Japanese patients. Our analyses involving 12 Japanese and 13 non-Japanese patients and studies by others indicate that (1) there is no panethnically prevalent mutation; (2) the Arg508Trp, Gly581Ser, and Val550Met mutations are found in both Japanese and non-Japanese populations; (3) the IVS10+5G-->A mutation is predominant and probably a founder mutation in European patients; (4) the 655-656insA, Leu237Pro, and 780delG mutations are unique in Japanese patients; (5) the spectrum of the mutations in the HLCS gene may vary substantially among different ethnic groups.     

小麦不同品种上麦蚜及其天敌的数量变动

试验结果表明小麦品种 (系 )的抗性对麦蚜种群数量影响很大 ,百株蚜量随着小麦品种抗性增强而下降。而同一小麦品种对不同种蚜虫的抗性存在质的差异 ,铭贤 1 69品种 ,蚜高峰期百株蚜量麦长管蚜 63 0头 ,禾谷缢管蚜只有 1 1 5头 ,两者相差 5 5倍。另一方面 ,小麦品种抗性对麦田天敌的种群数量影响不大 ,而对天敌的发生期有些影响。因此 ,小麦品种抗性、天敌对麦蚜的自然控制能力 ,可把小麦中后期的蚜虫虫口密度控制在经济损失允许水平之下。     

The role of zinc in caspase activation and apoptotic cell death

In addition to its diverse role in many physiological systems, zinc (Zn) has now been shown to be an important regulator of apoptosis. The purpose of this review is to integrate previously published knowledge on Zn and apoptosis with current attempts to elucidate the mechanisms of action of this biometal. This paper begins with an introduction to apoptosis and then briefly reviews the evidence relating Zn to apoptosis. The major focus of this review is the mechanistic actions of Zn and its candidate intracellular targets. In particular, we examine the cytoprotective functions of Zn which suppress major pathways leading to apoptosis, as well as the more direct influence of Zn on the apoptotic regulators, especially the caspase family of enzymes. These two mechanisms are closely related since a decline in intracellular Zn below a critical threshold level may not only trigger pathways leading to caspase activation but may also facilitate the process by which the caspases are activated. Studies by our laboratory in airway epithelial cells show that Zn is co-localized with the precursor form of caspase-3, mitochondria and microtubules, suggesting this Zn is critically placed to control apoptosis. Further understanding the different pools of Zn and how they interact with apoptotic pathways should have importance in human disease.