The Physiological Effects of Ethrel on Seedlings of Second Season Rice

Spray of ethrel (1000 ppm)to seedlings of double-cropping second season rice at 5-leaf stage can control plant height and root length, and consequently makes seedlings strong and tough. The ABA content and ethylene released by young seedling were significantly higher than the control. However, there were some changes: cell elongation inhibited, leaf area decreased, and leaf color became dark green, photosynthetic rate increased, translocation of photosynthetate in leaf sheath enhanced, leaf emergence was rapid. The growth of root system and root vigor were though temporarily inhibited, but slightly increased after transplantation. All these are beneficial to seedling quality, the plant growth and development after transplantation, which subsequently bring about positive effects on stimulating early heading and on increasing rice yield.     

Approach to Physiological Functions of Ethrel in the Ripening of Cotton Boll

Both leaf and boll of cotton can absorb ethrel and the acceptor releases ethylene rapidly. Ethrel absorbed by leaves can release ethylene in bolls, whereas that absorbed by bolls cannot release ethylene in leaves. Bolls treated with ethrel has two peaks in ethylene releasing. The first peak appears about two days after treatment, and the second appears before the splitting of boll. The control has only one peak in ethylene releasing which appears eight days later than the second peak of the bolls treated with ethrel. This coincides with the fact that ethrel enables bolls to split seven to ten days earlier. The releasing of ethylene by cotton bolls is closely related to temperature, and is accelerated with increasing temperature no matter cotton bolls are treated with ethrel or not.     

链格孢菌原生质体的制备与限制性内切酶介导整合(REMI)转化的致病性诱变

以链格孢菌Alternariaalternata菌株NEW为供试菌株,研究了菌龄、酶系统、酶解时间、酶解温度及稳渗剂对链格孢菌原生质体制备的影响。结果表明,制备链格孢菌原生质体比较适宜的条件为PD液体培养基培养20h,以0.7mol/LNaCl为稳渗剂、1%LysingEnzyme、1%Drislase和1%Snailase3种酶溶液混合使用,30℃酶解3h。对原生质体进行了限制性内切酶介导整合(REMI)转化,筛选到了链格孢菌弱致病突变株NEW001,为致病相关基因的标记和克隆打下了基础。     

补体攻膜复合体致肾小球脏层上皮细胞粘附性改变研究

为探讨膜性肾病中补体攻膜复合体(MAC)介导蛋白尿机制,本研究制作了MAC致肾小球脏层上皮细胞(GVEC)亚溶破模型。通过对细胞局部粘附及相关蛋白的观察发现,MAC亚溶破致伤GVEC后,其粘附性发生改变。其机理与ECM分泌失调、膜硫酸化物质及整合素减少、细胞骨架重排有关。这些改变导致体内GVEC脱附,足突退缩融合,从而参与膜性肾病的蛋白尿产生。     

叶色草蛉的生物学研究1:热常数和发育速率(英文)

利用优选法和快速估计法对叶色草岭在７个温度处理下的个体发育的过程进行了测算,确定了它的卵期、幼虫期、蛹期及幼虫期的一龄、二龄和三龄的发育起始温度（Ｔ_０）和有效积温（Ｋ）,前一方法的结果Ｔ_０分别为１４．２０、１１．５５、８．２７、１０．８４、１０．０３和１２．７９℃;Ｋ分别为５３．８２、１５１．５８、２４３．８５、５２．１４、４５．８６和５５．２０日／度。后一方法的结果Ｔ_０分别为１４．３３、１２．１８、８．３８、 １１．６２、１０．６６和１３．２８℃;Ｋ分别为５４．４１、１５７．６２、２４５．２１、５４．６１、４７．５２和５７．０４日／度。同时根据Ｌｏｇｉｓｔｉｃ曲线方程确定了不同温度条件下叶色草蛉的发育速率计算式。     

Hypothesis: A recurrent, moderate activation fosters systemic autoimmunity — the apoptotic roles of TCR, IL-2 and fas ligand

Studies of several gene knockout mice suggest an interesting association of a moderate T cell response with systemic autoimmune diseases. In addition, CD95 ligand (FasL) expression in some strains of these mice is impaired. Because FasL is critically involved in regulating peripheral tolerance, there may be a link between autoimmune diseases and a moderate T cell response that cannot activate the FasL gene. Here, we propose that there are two thresholds of T cell activation. When moderately stimulated, T cells can be activated to the low (1st) threshold, which permits the induction of CD40L, IL-2, IL-4, and other components that help the immune response. The high (2nd) activation threshold can only be achieved by a strong and concurrent stimulation through TCR and IL-2R. Once the high threshold is reached, FasL is produced to induce apoptosis of the activated T and B cells. In the absence of the FasL-mediated downregulation, the activated B cells become efficient antigen-presenting cells for self-antigens and excellent responders for T cell help. Such an exacerbating condition, induced by recurrent and moderate activation, favors the development of autoreactive T cells and autoantibody production. Evidence supporting this hypothesis and some predictions that can be tested are described.     

Characterization of the Shank family of synaptic proteins. Multiple genes, alternative splicing, and differential expression in brain and development.

Shank1, Shank2, and Shank3 constitute a family of proteins that may function as molecular scaffolds in the postsynaptic density (PSD). Shank directly interacts with GKAP and Homer, thus potentially bridging the N-methyl-D-aspartate receptor-PSD-95-GKAP complex and the mGluR-Homer complex in synapses (Naisbitt, S., Kim, E., Tu, J. C. , Xiao, B., Sala, S., Valtschanoff, J., Weinberg, R. J., Worley, P. F., and Sheng, M. (1999) Neuron 23, 569-582; Tu, J. C., Xiao, B., Naisbitt, S., Yuan, J. P., Petralia, R. S., Brakeman, P., Doan, A., Aakalu, V. K., Lanahan, A. A., Sheng, M., and Worley, P. F. (1999) Neuron 23, 583-592). Shank contains multiple domains for protein-protein interaction including ankyrin repeats, an SH3 domain, a PSD-95/Dlg/ZO-1 domain, a sterile alpha motif domain, and a proline-rich region. By characterizing Shank cDNA clones and RT-PCR products, we found that there are four sites for alternative splicing in Shank1 and another four sites in Shank2, some of which result in deletion of specific domains of the Shank protein. In addition, the expression of the splice variants is differentially regulated in different regions of rat brain during development. Immunoblot analysis of Shank proteins in rat brain using five different Shank antibodies reveals marked heterogeneity in size (120-240 kDa) and differential spatiotemporal expression. Shank1 immunoreactivity is concentrated at excitatory synaptic sites in adult brain, and the punctate staining of Shank1 is seen in developing rat brains as early as postnatal day 7. These results suggest that alternative splicing in the Shank family may be a mechanism that regulates the molecular structure of Shank and the spectrum of Shank-interacting proteins in the PSDs of adult and developing brain.     

乡村生态学概论

城市生态学已逐渐发展成一门受众人肯定的生态学分支学科,但乡村生态学未引起广泛重视。本文定义乡村生态学为研究村落形态、结构、行为及其与环境本底统一体客观存在的生态学分支科学。村落是以一定年龄结构、一定数量人口或人群为基本特征,以户为组成单位,以土地为经营对象,以相应的生物(牲畜和作物)为主要价值资源的人类聚居的空间单元。村落除具空间和生命涵义外,还直接联系地理位置、地形地势、气候、土壤和植被等景观要素与资源参数;同时,它还与历史传统、社会习俗等多方面复杂因素有关。乡村生态学的意义在于揭示村落与所有这些相关因素的关系,并用以指导乡村建设。     

离心法与细胞显微操作法对内皮细胞-白细胞黏附特性的初步研究

将哮喘病理血清与在体外培养的大鼠肺内皮细胞共同孵育,分别用离心法和显微操纵技术对细胞黏附进行体外研究。离心结果显示,病理血清刺激下的内皮细胞比正常情况更易与白细胞发生黏附。离心力高到一定程度可以解离部分黏附。从进一步的细胞显微操纵实验看病理血清刺激内皮细胞的功能状态,影响内皮细胞与白细胞发生黏附