原核微生物之竿菌

140多年前发表的竿菌和杆(小杆)菌同属最早发现和定名的细菌类之一,迄今已有成百上千的菌种得到鉴定、分类和命名。中文微生物学命名和整理滞后,引发了一些不必要的麻烦和困惑,不利于我国微生物学的普及发展和国际交流。本文试图对已经合格发表的近100属1 130多种竿菌进行系统的形态学(含芽孢和/或孢子)、生境、生物化学和细菌属性梳理和分类,理清和制定竿菌种属的中文-拉丁文互译规则,有利于推动中外交流和发展。     

马拉硫磷和敌百虫混用和轮用的研究:淡色库蚊的酯酶同功酶与抗性的关系

用马拉硫磷和敌百虫单独处理30代和31代的淡色库蚊,见到对马拉硫磷和敌百虫的抗性分别为敏感品系的286和303倍,而以马拉硫磷和敌百虫轮用(32代)和混用(31代)处理的品系对马拉硫磷和敌百虫的抗性均在70倍以下。 离体酶的活性测定和酯酶同功酶的酶谱分析均表明,抗性品系体内羧酸酯酶活力高于敏感品系;酸性磷酸酯酶和乙酰胆碱酯酶的活力两者差异不显著,可见马拉硫磷和敌百虫的抗性主要和羧酸酯酶活力的增长有关。     

鲎素的抗菌靶点初探

采用体外抑菌法测定鲎素的抑菌动力学特点,钼酸铵比色法和紫外吸收法分别检测细菌与鲎素共同孵育前后无机磷和大分子泄漏情况,扫描电镜和透射电镜观察细菌与鲎素共同孵育前后细菌形态和结构的变化,紫外吸收法和凝胶电泳法分别观察鲎素对细菌基因组DNA和质粒DNA结构的影响,质粒转化实验检测鲎素对质粒DNA复制和转录功能的影响.结果表明,鲎素对革兰氏阳性菌和阴性菌具有不同的抑菌动力学特点,经鲎素处理的细菌,胞内无机磷和大分子泄漏显著,细胞壁膜和菌体遭到不同程度的破坏,鲎素可与细菌基因组DNA和质粒DNA结合,高浓度鲎素有可能使DNA发生断裂,进而使质粒DNA复制和转录功能受到抑制.上述结果提示,鲎素的抗菌靶点至少包括细胞壁膜和菌体DNA.     

皮层神经元动作电位不应期和阈电位与神经元动作电位编码的关系

目的：测量和比较感觉运动皮层Ⅱ/Ⅲ层锥体神经元和中间神经元的内在特性并研究其与动作电位编码频率和精确性的关系。方法：采用全细胞电流钳记录模式,获得的数据输入pClamp和Origin进行处理分析。结果：与锥体神经元相比,中间神经元群集动作电位具有较低的阈电位水平和较短的不应期,从而中间神经元具有较高的动作电位编码频率和精确性。结论：皮层神经元动作电位的阈电位水平和不应期调控动作电位的编码频率和精确性。     

玉米低温冷害动态评估和预测方法

为了防御和减轻玉米低温冷害,应用改进的玉米生长发育和干物质积累动态模型,采用新的玉米低温冷害指标和参数,建立了玉米低温冷害发生及损失程度的动态预测和评估方法.该方法遵循积温学说和玉米生物学、生态学原理,用相对积温作为发育期预报和灾害判别的主导因子,用干物质亏缺率代表冷害减产率.经代表地区不同气候年型的验证和试用,证明该冷害预报和评估方法具有较好的客观性和适用性,经过参数和指标调整后,可应用于东北地区各地.     

稀土叶面肥对葡萄园节肢动物群落多样性和稳定性的影响

为了明确施用稀土镧和钕的叶面肥对江淮丘陵和黄河故道葡萄园节肢动物群落多样性和稳定性的影响,通过系统调查和t检验得出,肥东县和萧县两地镧和钕与清水(CK1)和醋液(CK2)之间,捕食性天敌的物种数和个体数、植食性昆虫物种数和个体数和总群落的多样性指数差异均不显著。总群落物种数与个体数的比值(稳定性值),肥东镧和钕与CK1之间t值为0.5592和1.0922,与CK2之间t值为1.2407和1.9178;萧县镧和钕与CK1之间t值为0.3533和0.8969,与CK2之间的t值为0.7067和0.4484;t值均小于t0.05(2.07),其群落稳定性差异均不显著,表明镧和钕叶面肥对葡萄园节肢动物群落多样性和稳定性影响不显著。对12次调查的捕食性天敌和植食性昆虫的物种数比值(Sn/Sp)进行分析,肥东喷镧和喷钕处理与CK1之间Sn/Sp的比值t检验的t值为0.5111和0.1499,与CK2的t值为0.1146和0.2466,CK1与CK2的t值为0.3476;萧县喷镧和喷钕处理与CK1之间Sn/Sp的比值t检验的t值为0.0976和0.0547,与CK2的t值为0.0975和0.1749,CK1与CK2的t值为0.2337,t值均小于t0.05,他们之间差异均不显著,表明两地两种稀土叶面肥对葡萄园节肢动物群落内食物网络关系的复杂性影响不显著。对12次调查捕食性天敌和植食性昆虫的个体数比值(Sa/Sb)进行分析,肥东喷镧和喷钕处理与CK1之间Sa/Sb的比值t检验的t值为0.9427和0.9727,与CK2的t值为0.5023和0.5342,CK1与CK2的t值为0.4957;萧县喷镧和喷钕处理与CK1之间Sa/Sb的比值t检验的t值为0.8820和0.0345,与CK2的t值为0.0741和1.0572,CK1与CK2的t值为0.8571,t值均小于t0.05,它们之间差异均不显著,表明两地两种稀土叶面肥对葡萄园节肢动物群落内食物网络关系的益害比影响不显著。     

沙漠化对科尔沁沙质草地生态系统碳氮储量的影响

通过野外调查,研究了沙漠化对科尔沁沙质草地生态系统碳、氮储量的影响.结果表明:沙漠化对草地碳、氮含量和储量具有显著影响,随着草地沙漠化的进程,草地碳、氮含量和储量明显下降.与非沙漠化草地相比,轻度、中度、重度和严重沙漠化草地0～100cm深土壤有机碳和全氮含量分别下降了56.06%和48.72%、78.43%和74.36%、88.95%和84.62%、91.64%和84.62%,植物组分中的碳、氮含量分别下降了8.61%和6.43%、0.05%和25.71%、2.58%和27.14%、8.61%和27.86%;轻度、中度、重度和严重沙漠化草地地上植物组分中的碳、氮储量分别下降了25.08%和27.62%、30.90%和46.55%、73.84%和80.62%、90.89%和87.31%,0～100cm深地下植物组分中碳和全氮储量分别下降了50.95%和43.38%、75.19%和71.04%、86.76%和81.48%、91.17%和83.17%.2000年科尔沁沙地沙漠化草地总面积为30152.7km2,因沙漠化损失的碳、氮总储量高达107.53和9.97Mt.草地碳、氮含量的下降主要源于风蚀过程中土壤细颗粒的损失.土壤的粗化和贫瘠化最终导致了植物和凋落物中碳、氮储量的明显下降.     

茶叶中咖啡因和茶多酚提取技术研究

本文研究茶叶品种和质量、提取剂种类和萃取溶剂量对咖啡因和茶多酚提取得率、提取率和纯度的影响,结果表明:茶叶质量高,咖啡因和茶多酚的含量、得率和纯度就高。95％乙醇提取咖啡因和茶多酚的得率、提取率和纯度最高。1％氧化钙水溶液单纯提取咖啡因的得率、提取率和纯度较高。增加萃取次数和萃取溶剂量可提高咖啡因和茶多酚的得率,对产品纯度没有影响。     

可吸入颗粒物和细颗粒物基本特征、监测方法及森林调控功能

可吸入颗粒物(PM10)和细颗粒物(PM2.5)既是造成空气污染的主要原因之一,也是大部分城市的首要污染物.本文在分析PM10和PM2.5对环境和人类健康影响的基础上,重点综述了PM10和PM2.5组成、来源、质量浓度变化规律及影响因素;介绍了PM10和PM2.5监测网络布局、分析方法的原理和特点;归纳了个体和区域尺度上森林去除PM10和PM25的研究方法、速率和影响机制.探讨了目前该领域研究中存在的问题:由于缺乏不同梯度和背景地区大气PM10和PM2.5比较观测研究,未能揭示各类因素对PM10和PM2.5的复合影响;合理布局PM10和PM2.5监测网络、正确选择监测方法,并以手工方法所获数据作为比对和校验,是保证监测数据有效性的基础;有关森林去除PM2.5研究较少,未能在细胞、组织、器官和个体水平上阐明其去除PM10和PM2.5的生理过程和生态学机理.     

访美见闻

去年应美方邀请,又通过科协和微生物学会的支持和联系,有机会赴美进行了五个月的学术交流和访问。在美期间由于美国科学院和美中学术交流委员会(CSCPRC)的支持和协助,访问了30多个城市,20多所大学和研究所,并参加了美国植物病理学会的年会。     

Endogenous opiates: 1995

This article is the eighteenth installment of our annual review of research concerning the opiate system. It includes articles published during 1995 reporting the behavioral effects of the opiate peptides and antagonists, excluding the purely analgesic effects. The specific topics covered this year include stress; tolerance and dependence; eating; drinking; gastrointestinal, renal, and hepatic function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; sex, pregnancy, and development; immunological responses; and other behaviors.     

L’évolution du cerveau se poursuit

After the strong climatic shocks which happened over and over again, which made the hands free and which started the biological and cultural development of Hominoids, everything depended on the brains of the species concerned and their ability to correlate and invent, because of the constant pressure of their natural and social environment. We are less interested in describing 15 steps here, than in specifying, for each reference mark in a non-stop process, the level reached by mental ability as much cognizantly as affectingly and the neurological bases, which allowed them to occur. This progression was based on the complexification (through epigenesis) of intracerebral connections at different levels allowing us to have large conscience and language, which are the bases of our freedom (via feelings, re-entries and mental pictures). Consequently, men could progressively have control of natural powers, inert ones first (tools), then moving ones (fire), living (hunting) and social ones (slavery); at last, men could free himself from them and perceive them objectively, dominate them, and conceive them in time and abstraction. Writing, then philosophy, then counting and logic have only recently crowned the progress towards the conquest of abstract and humanism through reversive action. The whole show phyletical gradualism, which is still progressing.     

Endogenous opiates: 1993

This paper is the sixteenth installment of our annual review of research concerning the opiate system. It is restricted to papers published during 1993 that concern the behavioral effects of the endogenous opiate peptides, and does not include papers dealing only with their analgesic properties. The specific topics this year include stress; tolerance and dependence; eating; drinking; gastrointestinal, renal, and hepatic function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; development; immunological responses; and other behaviors.     

The Role of Uncomposted Materials,Composts, Manures,and Compost Extracts in Reducing Pest and Disease Incidence and Severity in Sustainable Temperate Agricultural and Horticultural Crop Production—A Review

This review evaluates evidence of the impactof uncomposted plant residues, composts, manures, and liquid preparations made from composts (compost extracts and teas) on pest and disease incidence and severity in agricultural and horticultural crop production. Most reports on pest control using such organic amendments relate to tropical or arid climates. The majority of recent work on the use of organic amendments for prevention and control of diseases relates to container-produced plants, particularly ornamentals. However, there is growing interest in the potential for using composts to prevent and control diseases in temperate agricultural and horticultural field crops and information concerning their use and effectiveness is slowly increasing. The impact of uncomposted plant residues, composts, manures, and compost extracts/teas on pests and diseases is discussed in relation to sustainable temperate field and protected cropping systems. The factors affecting efficacy of such organic amendments in preventing and controlling pests and disease are examined and the mechanisms through which control is achieved are described.     

Carboxylesterases in lipid metabolism: from mouse to human

Mammalian carboxylesterases hydrolyze a wide range of xenobiotic and endogenous compounds, including lipid esters. Physiological functions of carboxylesterases in lipid metabolism and energy homeostasis in vivo have been demonstrated by genetic manipulations and chemical inhibition in mice, and in vitro through (over)expression, knockdown of expression, and chemical inhibition in a variety of cells. Recent research advances have revealed the relevance of carboxylesterases to metabolic diseases such as obesity and fatty liver disease, suggesting these enzymes might be potential targets for treatment of metabolic disorders. In order to translate pre-clinical studies in cellular and mouse models to humans, differences and similarities of carboxylesterases between mice and human need to be elucidated. This review presents and discusses the research progress in structure and function of mouse and human carboxylesterases, and the role of these enzymes in lipid metabolism and metabolic disorders.     

Endogenous opiates: 1994

This article is the 17th installment of our annual review of research concerning the opiate system. It includes papers published during 1994 involving the behavioral, nonanalgesic, effects of the endogenous opiate peptides. The specific topics covered this year include stress; tolerance and dependence; eating; drinking; gastrointestinal, renal, and hepatic function; mental illness and mood; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; sex, pregnancy, and development; immunological responses; and other behaviors.     

Uptake of six heavy metals by oat as influenced by soil type and additions of cadmium,lead, zinc and copper

Summary The influence of heavy metal additions on availability and uptake of cadmium, lead, zinc, copper, manganese and iron by oat was studied. The experiments were carried out as pot experiments using sandy loam, sandy soil and organic soil. Selective extractants were used to remove metals held in different soil fractions.Lead and copper were preferently bound by organics and oxides, zinc by oxides and inorganics, and cadmium by inorganics and organics.Addition of cadmium to the soils resulted in higher cadmium concentrations in all plant parts but lower concentrations of lead, zinc, copper, manganese and iron, and the accumulation indexes of these metals were also lower when cadmium was added to the soil.Addition of cadmium plus lead, zinc and copper resulted in higher cadmium concentrations in leaves and straw of plants grown in sandy loam and sandy soil, but lower concentrations when plants were grown in organic soil as compared with the results when cadmium was added separately. The transfer of cadmium, lead, zinc and copper from soil to plant was greatest from sandy soil, and zinc and cadmium were more mobile in the plant than were lead and copper.Cadmium concentrations in leaves correlated significantly with CaCl₂ and CH₃COOH extractions in sandy loam and sandy soil and with CH₃COOH extractions in organic soil.Generally, the total metal uptake was lowest from organic soil.     

Endogenous opiates: 1988

This paper is the eleventh installment in our annual review of the research during the past year involving the endogenous opiate system. It is concerned with nonanalgesic and behavioral studies of the opiate peptides that were published during 1988. The specific topics this year include stress; tolerance and dependence; eating; drinking; gastrointestinal, renal, and hepatic functions; mental illness; learning, memory, and reward; cardiovascular responses; respiration and thermoregulation; seizures and other neurological disorders; electrical activity; locomotor activity; sex, pregnancy, and development; immunology and cancer; and other behavior.     

Electrolyte changes in plasma and urine of athletes during acute and rigorous bed rest and ambulatory conditions

Rigorous bed rest (RBR) induces significant electrolyte changes, but little it is not known about the effect of acute bed rest (ABR) (i.e., abrupt confinement to a RBR). The aim of this study was to measure urinary and plasma electrolyte changes during ABR and RBR conditions. The studies were done during 3 d of a pre-bed-rest (BR) period and during 7 d of an ABR and RBR period. Thirty male trained athletes aged, 24.4 ± 6.6 yr were chosen as subjects. They were divided equally into three groups: unrestricted ambulatory control subjects (UACS), acute-bed-rested subjects (ABRS), and rigorous-bed-rested subjects (RBRS). The UACS group experienced no changes in professional training and daily activities. The ABRS were submitted abruptly to a RBR regimen and without having any prior knowledge of the exact date and time when they would be subjected to an RBR regimen. The RBRS were subjected to an RBR regime on a predetermined date and time known to them from the beginning of the study. Sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), and phosphate (P) in plasma and urine, plasma renin activity (PRA) and plasma aldosterone (PA), physical characteristics, peak oxygen uptake, and food and water intakes were measured. Urinary Na, K, Ca, Mg, and P excretion and plasma Na, K, Mg, Ca, and P concentration, PRA, and PA concentration increased significantly (p ≤ 0.01), whereas body weight, peak oxygen uptake, and food and water intakes decreased significantly in the ABRS and RBRS groups when compared with the UACS group. However, urinary and plasma Na, K, Mg, P, and Ca, PRA, and PA values increased much faster and were much greater in the ABRS group than in the RBRS group. Plasma and urinary Na, K, Ca, Mg, and P, PRA and PA levels, food and water intakes, body weight, and peak oxygen uptake did not change significantly in the UACS group when compared with its baseline control values. It was shown that RBR and ABR conditions induce significant increases in urinary and plasma electrolytes; however, urinary and plasma electrolyte changes appeared much faster and were much greater in the ABRS group than the RBRS group. It was concluded that the more abruptly motor activity is ended, the faster and the greater the urinary and plasma electrolyte change.