庐山野生观赏植物资源多样性及持续利用对策

庐山是我国著名的风景旅游和避暑胜地,也是我国中亚热带北缘植物多样性的宝库．本文在广泛调查、收集、整理的基础上,研究了庐山野生观赏植物资源多样性特征、分布、类型及其配置．本区分布有野生观赏植物５２８种,隶属于１１５科２９０属,其中乔木类１３８种,灌木类１４０种,藤木类５２种,草本类１９８种．并根据开发与保护现状对庐山野生观赏植物资源多样性的持续利用提出了切实可行的对策．     

A Novel Class of Herbicides (Specific Inhibitors of Imidazoleglycerol Phosphate Dehydratase)

A new mode of herbicidal action was established by finding specific inhibitors of imidazoleglycerol phosphate dehydratase, an enzyme of histidine (His) biosynthesis. Three triazole phosphonates inhibited the reaction of the enzyme with Ki values of 40 [plus or minus] 6.5, 10 [plus or minus] 1.6, and 8.5 [plus or minus] 1.4 nM, respectively, and were highly cytotoxic to cultured plant cells. This effect was completely reversed by the addition of His, proving that the cytotoxicity was primarily caused by the inhibition of His biosynthesis. These inhibitors showed wide-spectrum, postemergent herbicidal activity at application rates ranging from 0.05 to 2 kg/ha.     

保护生物学概要

保护生物学的形成是对生物危机的反应和生物科学迅速发展的结果。它是应用科学解决由于人类活动干扰或其它因素引起的物种、群落和生态系统出现的问题的新学科。其”目的是提供保护生物多样性的原理和工具“,其基础科学和应用科学的综合性交叉学科。系统学、生态学、生物地理学和种群生态学的原理和方法是保护生物学重要的理论和实践基础。     

Syntheses, spectra and crystal structures of ruthenium(II) complexes with polypyridyl: [Ru(bipy)2(phen)](ClO4)2 · H2O and [Ru(bipy)2(Me-phen)](ClO4)2

Two ruthenium(II) complexes with polypyridyl, Ru(bipy)₂(phen)](ClO₄)₂·H₂O (1) and [Ru(bipy)₂(Me-phen)](ClO₄)₂ (2), (phen = 1,10-phenanthroline, bipy = 2,2′-bipyridine, Me-phen = 5-methyl-1,10-phenanthroline), were synthesized and characterized by IR, MS and NMR spectra. Their structures were determined by single crystal X-ray diffraction techniques. The strong steric interaction between the polypyridyl ligands was relieved neither by the elongation of the Ru---N bonds nor increase of the N---Ru---N bite angles. The coordination sphere was distorted to relieve the ligand interaction by forming specific angles (δ) between the polypyridyl ligand planes and coordination planes (N---Ru---N), and forming larger twisted angles between the two pyridine rings for each bipy. The bond distances of Ru---N(bipy) and Ru---N(phen) were virtually identical with experimental error, as expected of π back-bonding interactions which statistically involve each of the ligands present in the coordination sphere.     

国产前原鹅观草的订正

对我国文献中记载的前原鹅观草（Ｒｏｅｇｎｅｒｉａｍａｙｅｂａｒａｎａ（Ｈｏｎｄａ）Ｏｈｗｉ）的标本和植物,与原产于日本的该种进行了比较形态学、细胞学研究,二者差异显著。作者认为我国所记载的该种种名应是山东鹅观草（Ｒｏｅｇｎｅｒｉａｓｈａｎｄｏｎｇｅｎｓｉｓ（Ｂ．Ｓａｌｏｍｏｎ）Ｊ．Ｌ．Ｙａｎｇ,Ｙ．Ｈ．ＺｈｏｕｅｔＹｅｎ）,其内稃先端钝圆,长为外稃的３／４,染色体数为２ｎ＝４ｘ＝２８,具ＳＹ染色体组,结实率达９０％以上,过去被错定为Ｒ．ｍａｙｅｂａｒａｎａ。而Ｒ．ｍａｙｅｂａｒａｎａ在日本系一天然杂种,其内稃先端尖,与外稃等长或稍短,染色体数为２ｎ＝６ｘ＝４２,具ＨＳＹ染色体组,结实率极低,仅０．２％～０．４％。     

Intracellular serine proteinase behaves as a heat-stress protein in nongrowing but as a cold-stress protein in growing populations of Bacillus megaterium

A temperature increase from 35° to 40–42°C enhances the rise of cytoplasmic serine proteinase (ISP1) activity in Bacillus megaterium incubated in a sporulation medium. A temperature shift from 27°C in the growth medium to 35°C in the sporulation medium has the same effect. Elevated temperature stimulates the increase of ISP1 level when applied immediately after the transfer of cells from the growth to the sporulation medium (at T₀) or at T₃, when sporulation becomes irreversible. The cytoplasmic PMSF-resistant activity or the proteolytic activity associated with the membrane fraction is stimulated only slightly or not at all. A temperature increase to 45–47°C suppresses the rise of proteolytic activities in all cell fractions. In addition to the elevation of the ISP1 activity by an upward temperature shift, the rise of this enzyme in nongrowing cells is also stimulated by osmotic stress. In growing populations, in contrast to the rise of the ISP1 activity caused by elevated temperature in nongrowing cells, this proteinase is induced by low temperatures (24–27°C). The ISP1 activity roughly correlates with the enzyme protein concentration determined by immunoblotting.     

Differential modulation of carbachol and trans-ACPD-stimulated phosphoinositide turnover following traumatic brain injury

In the fluid percussion model of traumatic brain injury (TBI), we examined muscarinic and metabotropic glutamate receptor-stimulated polyphosphoinositide (PPI) turnover in rat hippocampus. Moderate injury was obtained by displacement and deformation of the brain within the closed cranial cavity using a fluid percussion device. Carbachol and (±)-1-Aminocyclopentane-trans-1,3.-dicarboxylic acid (trans-ACPD)-stimulated PPI hydrolysis was assayed in hippocampus from injured and sham-injured controls at both 1 hour and 15 days following injury. At 1 hour after TBI, the response to carbachol was enhanced in injured rats by up to 200% but the response to trans-ACPD was diminished by as much as 28%. By contrast, at 15 days after TBI, the response to carbachol was enhanced by 25% and the response to trans-ACPD was enhanced by 73%. The ionotropic glutamate agonists N-methyl-D-aspartate (NMDA), and -amino-3 hydroxy-5-methyl-4-isoxazolepropionate (AMPA), did not increase PPI hydrolysis in either sham or injured rats and injury did not alter basal hydrolysis. Thus, hippocampal muscarinic and metabotropic receptors linked to phospholipase C are differentially altered by TBI.Abbreviations used TBI traumatic brain injury - EAA excitatory amino acids - PPI polyphosphoinositides - IP inositol phosphates - NMDA N-methyl-D-aspartate - AMPA -amino-3-hydroxy-5-methylisoxazole-4-propionate - trans-ACPD (±)-1-Aminocyclopentanetrans-1,3-dicarboxylic acid - LTP long term potentiation     

Oxidative stress during exercise: Implication of antioxidant nutrients

Research evidence has accumulated in the past decade that strenuous aerobic exercise is associated with oxidative stress and tissue damage in the body. There is indication that generation of oxygen free radicals and other reactive oxygen species may be the underlying mechanism for exercise-induced oxidative damage, but a causal relationship remains to be established. Enzymatic and nonenzymatic antioxidants play a vital role in protecting tissues from excessive oxidative damage during exercise. Depletion of each of the antioxidant systems increases the vulnerability of various tissues and cellular components to reactive oxygen species. Because acute strenuous exercise and chronic exercise training increase the consumption of various antioxidants, it is conceivable that dietary supplementation of specific antioxidants would be beneficial.     

醋酸纤维素膜为基础的葡萄糖生物传感器的研制

用共价法将酶固定在醋酸纤维素膜上,方法简便易行,制造的酶膜稳定,比活力高。同时采用该方法制备了葡萄糖氧化酶酶膜,与氧电极组装成测定葡萄糖的生物传感器,线性范围为50~800mg／dl,仪器工作的最适pH为6．0,最适温度为40℃。将该膜与过氧化氢电极组装得到的传感器具有以下特性：线性范围为10~200mg／dl,最适pH为6．0,测定结果与酶试制盒有良好相关性。     

PFP的研究进展

焦磷酸:果糖-6-磷酸1-磷酸转移酶(PFP)可催化果糖-6-磷酸与果糖-1,6-二磷酸间的可逆转变.该酶广泛存在于各种高等植物及一些微生物体内.文章综述了90年代以来有关PFP的一些研究进展.包括:PFP的种类与亚基构成、活性中心、底物特异性、酶活性的调节及功能等.