山东省蚜虫名录

本是作1981-1993年对山东省蚜虫的调查结果,共记述12科,80属,184种和亚种及其寄主与分布,其中6种是中国新记录,97种是山东省新记录（右上角标记*）。     

岩豆凝集素的圆二色性与生物学活性关系的研究

岩豆凝集素（ＭＤＬ）的远紫外圆二色性谱（ＣＤ谱）显示２１６－２１７ｎｍ处的单一负峰。此时ＭＤＬ分子含有１６．２％的α螺旋,４６．３％的β折叠和３７．５％的无规卷曲。ｐＨ９．０时负峰红移至２２０ｎｍ,且在２１７－２２２ｎｍ处的峰值几乎相同;在２０－４０℃范围内,ＣＤ谱的变化甚微;６０℃时谱峰蓝移;在８０℃或１００℃时,２１２ｎｍ处出现一大负峰。１ｍｏｌ／Ｌ或２ｍｏｌ／Ｌ脲时,ＭＤＬ的ＣＤ谱已发生明显变化,二级结构单元也有变化,凝集兔红细胞的活性也随之减弱;随脲浓度的增加,ＭＤＬ的谱峰蓝移,最终在２１２ｎｍ处出现大负峰。当胍浓度为０．７５ｍｏｌ／Ｌ时,ＭＤＬ的ＣＤ谱即有明显变化和活性丧失;胍浓度继续增加,ＣＤ谱逐渐成为特征的无规卷曲的谱形。在ｐＨ９．０、温度超过８０℃、脲或胍浓度分别高于２ｍｏｌ／Ｌ和０．７５ｍｏｌ／Ｌ时,ＭＤＬ的ＣＤ谱发生显著变化的同时,其凝集兔红细胞的生物学活性全部丧失,分子的二级结构单元也发生很大改变。     

Effects of Temperature on Stereochemistry of Enzymatic Reactions

A brief discussion of the theoretical basis for effects of temperature on stereoselectivity of enzyme catalysed reactions is presented. In theory, the stereoselectivity of an enzymatic reaction can either increase or decrease as the reaction temperature is raised. The secondary alcohol dehydrogenase from Thermoanaerobacter ethanolicus reduces 2-butanone to (R)-2-butanol at 37° C, with increased stereoselectivity at higher temperatures and in the presence of NADP analogues. In contrast, at 37°, 2-pentanone and 2-hexanone are reduced to (S)-2-pentanol and (S)-2-hexanol, respectively, but the stereoselectivity decreases at higher temperatures and in the presence of NADP analogues. Reduction of racemic 2-methylbutanal by the primary alcohol dehydrogenase from T. ethanolicus gives (S)-2-methyl-1-butanol with greater stereospecificity at 35° (51% e.e.) than at 15° (14% e.e.). Horse liver alcohol dehydrogenase shows a preference for oxidation of the (S)-enantiomers of acyclic secondary alcohols at 25°, with a decrease in stereospecificity at higher temperatures.     

不同盐浓度对红萍生长及若干生理指标的影响

低盐浓度（０．２％ＮａＣｌ）对红萍生长有促进作用,处理组形态比对照厚而大朵,根系较长,且健壮,含水量与对照相似,但高浓度使萍体含水量明显减少。萍体ＮａＣｌ积累量随着培养液中盐浓度的增加而增加。生产指标测定表明,在低盐浓度下生长的红萍,叶绿素含量、固氮酶活性和全氮含量明显增加,可溶性糖含量则最低。低盐浓度促进红萍生长的原因可以归结为光合作用和固氮能力提高的结果。     

(蜓)类旋壁超微构造的研究——以麦(蜓)型旋壁为例

光学显微镜下的观察表明(蜒)类的旋壁属于钙质微粒壳类型,对它们的电镜观察揭示了组成旋壁的晶粒的大小、形态和排列方式.对具有致密层和蜂巢层型两层式旋壁的Triticites的电镜研究表明:其致密层由近等轴晶无定向排列而成;蜂巢层由短柱状晶定向排列组成板状复合体,进而组合成管状孔,镶嵌在不定向排列的近等轴品基质中构成.Pseudofusulina的致密层也由近等轴晶不定向排列构成,蜂巢层由粗柱晶定向排列组成纤状复合体,进而形成管状孔,镶嵌在近等轴晶基质中.     

乙型肝炎病毒表面抗原preS1在大肠杆菌中的表达与鉴定

本文报告利用pWR590质粒为载体,构建了含1ac启动子、β-半乳糖苷酶(1—590)基因、Xa因子的四肽识别位点和HBV preS1、preS2编码序列的表达质粒,并成功地在大肠杆菌中获得稳定表达。融合蛋白经Xa因子消化和高效液相层析,得到了preS1(1—91)纯肽。此肽特异性地与人肝细胞质膜结合,从而为肝细胞上存在preS1受体提供了直接的实验依据,也为分离和鉴定肝细胞上preS1受体打下了良好的基础。     

Microbial nitrogen and phosphorus co-limitation across permafrost region

The status of plant and microbial nutrient limitation have profound impacts on ecosystem carbon cycle in permafrost areas, which store large amounts of carbon and experience pronounced climatic warming. Despite the long-term standing paradigm assumes that cold ecosystems primarily have nitrogen deficiency, large-scale empirical tests of microbial nutrient limitation are lacking. Here we assessed the potential microbial nutrient limitation across the Tibetan alpine permafrost region, using the combination of enzymatic and elemental stoichiometry, genes abundance and fertilization method. In contrast with the traditional view, the four independent approaches congruently detected widespread microbial nitrogen and phosphorus co-limitation in both the surface soil and deep permafrost deposits, with stronger limitation in the topsoil. Further analysis revealed that soil resources stoichiometry and microbial community composition were the two best predictors of the magnitude of microbial nutrient limitation. High ratio of available soil carbon to nutrient and low fungal/bacterial ratio corresponded to strong microbial nutrient limitation. These findings suggest that warming-induced enhancement in soil nutrient availability could stimulate microbial activity, and probably amplify soil carbon losses from permafrost areas.     

中国优质水果资源的分布与适宜生态环境

根据农业部在80年代两次组织评选出的全国189个优质水果产地的生态环境资料,用微型电子计算机系统建立数据库,统计分析柑桔、苹果和梨优质产品的构成比例、产区分布地域及其适宜的环境指标和主栽品种的生态适应性,为果树良种区域化栽培与选育提供依据。     

Reproductive biology of guitar,Rhinobatos hynnicephalus

Synopsis Reproductive biology of the guitarfish,Rhinobatos hynnicephalus, from Xiamen coastal waters is described. Males have two functional testes. Spermatogenic cells in different seminiferous follicles are at different developmental stages while those in the same follicle are at the same stage. The development of claspers suggests that males mature at 380–400 mm TL. Females mature at 390–440mm TL. Both ovaries are functional. The first generation of ovarian eggs reach mature size when 22–24mm in diameter in April or May. The subsequent crop of eggs is ready for ovulation when the intrauterine embryos reach full term. The guitarfish is aplacentally viviparous. Longitudinal folds were observed on the internal wall of the uterus. Gestation takes one year and parturition takes place in June or July. Fecundity ranges from 2 to 9, with the large females usually being more fecund. Of 29 embryos ranging from 52–157mm TL, there were 15 females and 14 males indicating an embryonic sex ratio 1:1.