生长调解物质与植物水分状况的关系

水分是决定植物分布与作物生产力的主要因素之一。水分缺乏可引起植物生命活动的各个方面,包括生长发育、形态解剖与生理代谢等的改变,但是它的最主要而直接的影响是对生长发育的改变。生长调节物质对植物的生长发育有广泛的调节作用。因此关于植物在水分胁迫条件下,内源激素发生什么变化以及激     

植物生长调节物质

绿色植物的生长和发育不仅需要适宜的温度（气温、土温、日平均最高和最低温度）、光照强度和每日光照时数,必要的水分和氧气、二氧化碳以及氮、磷、钾等肥料元素,而且还受体内的多种微量的高效生理活性物质植物激素的调节。植物的激素含量常用毫克／升（mg／L）甚至更小单位表示。这就是说,只相当于植物鲜重的百万甚至千万分之几。更形象一些说,可看作将一匙蔗糖洒人一个面积为100m2、深为1m2的鱼塘中去的稀释度。可是,令人难解的是,这些微量的小分子物质竟然能在植物各器官间传递重要信息,指令生长和发育的方向和速度。如对黄瓜苗…     

植物生长调节物质的研究进展

述评了近几年国内外在植物激素与植物体内信使的传递、植物激素与基因诱导和表达、植物生长物质的复合使用、新型植物生长物质的开发及植物激素对提高植物抗逆性的作用等方面的研究进展,并展望了植物生长物质的发展趋势。     

几种新型植物内源生长调节物质

扼要介绍了系统素,茉莉酸,寡糖素,水杨酸,油菜素内酯和玉料赤霉烯酮等甾类激素,膨压素,多胺,乙酰胆碱等几种新型植物的内源生长调节物质。     

植物生长调节物质对果实生长发育的调控

本文就赤霉素、细胞分裂素、乙烯利对果实生长发育的调控作用进行了较为系统的论述,并对其在果树上的利用方法、时期、浓度等作了说明。     

植物生长物质与植物抗旱性的关系(综述)

脱落酸、乙烯、多胺和细胞分裂素等是与植物抗旱性关系较为密切的几种植物激素。文章就植物在遭受干旱胁迫时其体内激素变化及喷施植物生长调节剂对植物抗旱性的影响进行概述,为生化调控植物抗旱性提供参考。     

植物生长调节物质对杭白菊根芽诱导的影响

近年来,我们在用茎尖脱毒培养技术培养杭白菊(Chrysanthemum morifolium)无毒苗中获得了杭白菊的再生植株.……     

活性碳对培养基中植物生长调节物质的吸附作用

植物组织和细胞培养中经常使用活性碳(Johansson等1982,Fridborg和Eriksson 1975,Smith 1983,Steinitz和 Yahel 1982)。一般认为活性碳通过吸附而发生作用(Fridborg和Erik-sson 1975,Kohlenbach 和 Wernicke 1978,Martineau等1981)。但关于活性碳吸附何种     

藻类与植物生长物质

高等植物和藻类的发育之间具有相似性.尽管藻类具有多样性,但人们认为它们是比高等植物低级的生物类群,它们的形态比高等植物简单,但多数的发育过程却是相似的[1]。     

植物新型肽类生长调节物质--植物磺肽素

植物磺肽素是近年来在植物中发现的一种新的磺化短肽类生长调节物质.文章对植物磺肽素的发现及命名、生理作用、生物合成途径、作用机制及应用前景作了简要的介绍.     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Synthesis and antimicrobial studies of hydrazone derivatives of 4-[3-(2,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid and 4-[3-(3,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid

Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.

     

Novel compounds with potent CDK9 inhibitory activity for the treatment of myeloma

Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).