芽孢杆菌原生质体融合技术

微生物原生质体融合技术是近20年来国内外细胞工程领域的一个研究热点。1972年匈牙利学者Ｆｅｒｅｎｃｚｙ率先进行了微生物原生质体融合的研究[1]。在1976年匈牙利学者Ｆｏｌｄｅｒ和Ａｌｆｏｌｄ则首次报道了用ＰＥＧ或新生态磷酸钙诱导巨大芽孢杆菌(Ｂａｃｉｌｌｕｓｍｅｇａｔｅｒｉｕｍ)种内株间原生质体融合[2];同年法国的Ｓｃｈａｅｆｆｅｒ等也用ＰＥＧ诱导枯草芽孢杆菌(Ｂ.ｓｕｂｔｉｌｉｓ)进行种内株间原生质体融合获得成功[3]。有关芽孢杆菌原生质体融合的研究,在国内直至1981年才见报道[4]。经典改变微生物遗传性状的手段有两…     

阿拉善黄鼠巢区的研究

巢区(Home range)被公认为动物日常活动(取食、生殖、育幼等)的场所。有关鼠类的巢区,学者们已作了大量工作,但对黄鼠巢区的研究确很少,国内仅有吴德林等在《灭鼠与鼠类生物学研究报告》1978年第三集中报道了蒙古黄鼠的巢区。我省东部、中部广泛分布着阿拉善黄鼠(Spermophi-lus dauricus alashanicus Buchner)。已经证明该黄鼠是甘宁黄鼠鼠疫疫区的主要贮存宿主。     

动物活动区,领域及其估算方法

动物活动区、领域及其估算方法石建斌（国家环境保护局对外经济合作办公室北京１０００３５）１活动区（家域）、领域的概念英文中的ｈｏｍｅｒａｎｇｅ或ｈｏｍｅｒｅｇｉｏｎ一词是动物生态学中一个最基本的概念。由于人们的看法和理解不一而译成家域、家区或巢区等。实...     

高原鼠兔家群空间领域的季节性动态格局

为探讨高原鼠兔家群空间领域的季节特征,分别于2005年和2006年的5～8月,在青海省玛沁县,采用标志重捕法和最小多边形面积法对其家群巢区和核域进行了研究.结果表明,不同季节,高原鼠兔巢区和核域面积存在显著差异.5、6月份,成体巢区面积显著大于幼体,但二者核域面积却无显著差异;7月份,成体与第1胎幼体巢区及核域面积均显著大于第2胎.5、6月份雄性成体巢区显著大于7、8月份,6、7月份雌性成体巢区显著大于5月和8月份.巢区及核域面积均与家群个体数呈极显著性正相关关系,说明季节和家群结构均可对高原鼠兔空间领域产生重要作用.     

光皮桦优良单株自由授粉子代苗期性状的遗传变异

光皮桦 (ＢｅｔｕｌａｌｕｍｉｎｉｆｅｒａＨ .Ｗｉｎｋｌ.)为落叶阔叶大乔木 ,零星分布于我国南方各省 (区 ) [1] 。近年来 ,由于装饰装璜市场对光皮桦木材的需求量急剧增加 ,使得天然林遭到过度采伐 ,造成光皮桦天然林资源锐减 ,致使光皮桦可利用资源极少 ,处于渐危状态。有关学者就光皮桦的天然种群结构、种群动态等进行研究 ,探明了光皮桦种群的结构特征和种群演变规律等[2～ 5] ,对光皮桦的繁殖方法及苗期生长特性也进行了探讨 ,揭示苗期生长特性随时间序列的变化趋势[6,7] ;但在遗传改良方面的研究甚少[8] 。鉴于此 ,作者在现有天然…     

微量元素硼对林木生长的影响

硼 (Ｂ)是植物生长过程中不可缺少的微量元素之一 ,它对植物中糖的运输、核酸与蛋白质的合成、光合作用、花粉萌发、受精和结实等均有作用。农业上对Ｂ的研究和应用较多。早在 192 3年英国人Ｗａｒｉｎｇｔｏｎ[4 5] 就报道Ｂ对植物生长发育的重要性。此后 ,曾多人对此研究进行了较为详细的综述[33,34 ,36 ,4 3] 。我国低Ｂ和缺Ｂ土壤分布很广 ,主要分布在东部 ,尤其是东南部[9] 。在这些地区报道甘蓝型油菜、棉花和一些果树出现缺Ｂ症状 ,如甘蓝型油菜“花而不实”和棉花“蕾而无花”等。黑龙江省曾发现小麦、大麦、玉米、大豆、甜菜等严重…     

高原鼠兔的繁殖空间及其护域行为的研究

1985-1987年在青海湖黑马河湖滨地区,心耳标法研究了高原鼠兔(OchotOttacurzoniae) 的繁殖空间及护域行为,结果表明高原鼠兔营群体家族式生活,具有巢区和领域。繁殖期,雌雄配对建立新的家庭,巢区发生相对变化。并以亲呢、长鸣、嗅味标记和驱逐等行为维护其领地。     

麝凤蝶形态观察及生物学特性

麝凤蝶Ｂｙａｓａａｌｃｉｎｏｕｓ(Ｋｌｕｇ)属鳞翅目凤蝶科 ,分布于我国大部分地区和日本、朝鲜等国 ,寄主植物是马兜铃、木防己。在浙江省 ,该蝶自然条件下 1年可繁殖 3代 ,以蛹越冬。该蝶成虫双翼狭窄、尾突修长 ,飞翔姿态优雅 ,极具观赏性 ,是蝴蝶馆内放飞展出的适宜种类。至目前为止 ,已有国内外学者在麝凤蝶成虫的发生[1] 、形态[3 ,6,7] 、生殖系统[8～ 10 ] 、性信息素[11] 、亚种的杂交[12 ] 和幼虫的饲料[13 ] 及蛹体的滞育[14 ] 等方面有过报道或有一些研究 ,但很少对其人工饲养和繁殖进行研究。为了保护生态环境 ,开发蝴蝶资源…     

短尾猴黄山鱼鳞坑群四季巢区的研究

本文采用无线电发讯器和直接跟踪观察等方法,研究了短尾猴黄山鱼鳞坑群四季巢区的利用与环境的关系。鱼鳞坑群的春季巢区为2.75平方公里,夏季为1.62平方公里,秋季为3.62平方公里,冬季为2.5平方公里。四季巢区有重叠现象,总面积为6平方公里;巢区的季节性垂直迁移现象不明显,与分布在黄山的短尾猴整体情况有所差异,反映了短尾猴适应环境而表现的一种生活样式。     

啮齿动物的巢区面积估算法

巢区(Home range)是动物在其巢附近进行取食、生殖、育幼等日常活动的区域(Burt 1940)。标志流放法是应用最广的调查啮齿动物巢区的方法,尤其是按方格式布笼。但对同一野外调查结果,由于估算方法不同,巢区估算值相差很大,并且至今尚无学者提出一致公认的估算法。1980年5-10月,我们在青海省门源县的高寒草甸生态系统定位站调查根田鼠的巢区,按多种估算法对同一批实际调查结果估计了巢区面积,并对结果进行了分析比较,检查其特点和优缺点,并提出修正平均值法,作为我们今后讨论根田鼠巢区动态的基础。 对方格式布笼的调查结果进行巢区的估算方法,基本上分二大类,图形法和概率性模型法。图形法是按照捕点分布划出巢区,并直接求出巢区面积,如最小面积法,包括或不包括周边地带法,最大距离法和复合散布图法。     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

2018年中国植物科学若干领域重要研究进展

2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。     

2017年中国植物科学若干领域重要研究进展

2017年中国植物科学继续保持高速发展态势, 重大成果频出, 具体表现在中国植物学家在国际顶级学术期刊发表的文章数量平稳上升。中国植物科学领域的研究工作者成果精彩纷呈, 如新型广谱抗病机制的发现、水稻广谱抗病遗传基础及机制和疫霉菌诱发病害成灾机制研究等。2017年中国生命科学领域十大进展评选中, 有两项植物科学领域的研究成果入选。水稻生物学、进化与基因组学和激素生物学等领域学科发展突出。另外, 值得一提的是, 长期从事高等植物与代谢途径调控分子网络研究和水稻品种设计育种的李家洋院士的研究成果“水稻高产优质性状形成的分子机理及品种设计”荣获2017年国家自然科学一等奖。这一具有重大国际影响的开创性贡献标志着中国植物科学在该领域的国际科学前沿居于引领和卓越地位。该文对2017年中国本土科学家在植物科学若干领域取得的重要研究成果进行了系统梳理, 旨在全面追踪和报道当前中国植物科学领域发展的最新前沿动态, 与广大读者共同分享我国科学家所取得的辉煌成就。     

我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义。综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望。     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.     

2018年中国植物科学若干领域重要研究进展

2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。     

我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义.综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望.     

Changes in aquatic vegetation in Rhine floodplain streams in Alsace in relation to disturbance

Abstract. Changes are described in aquatic vegetation in oligotrophic, groundwater-fed Rhine floodplain streams in Alsace (eastern France), resulting from disturbance. Disturbance factors include changes in nutrients, either permanent ones - effluent from a waste water treatment plant or trout hatcheries - or periodic ones: flooding. Regular inputs of high levels of phosphate and ammonia modified the macrophyte vegetation in these streams. The floristic composition, which was characteristic of oligotrophic waters upstream of the eutrophicated sector, changed to that of a eutrophic situation as originally found downstream. Periodic disturbance by floods which normally occur once a year, irregularly eutrophicates the small streams, causing the development of a mixture of eutrophic and oligotrophic species. Six macrophyte communities are distinguished, indicating different trophic levels. The aquatic vegetation is adapted to the variations of phosphate and ammonia levels. Hence, aquatic macrophytes can be used as bio-indicators of fluctuations in water nutrient levels in relation to the type of disturbance.     

Apoptosis in experimental myocardial infarction in situ and in the perfused heart in vitro

We report the appearance of apoptotic cells in experimental myocardial infarction (rabbit heart) in in situ and in vitro preparations. Apoptosis was recognized by intravital staining with Hoechst 33342 (Ho342), by nick-end labeling (TUNEL) and by DNA laddering. A steady rise in the relative number of apoptotic cardiomyocytes (apoptotic index) was noted in in situ preparations. Apoptosis was first noted 6 h after the onset of ischemia with its highest value occurring after 72 h. Apoptotic nuclei were absent in remote areas of the left and right ventricles. Apoptotic nuclei within the infarcted area showed diminished intensity of Ho342 fluorescence. Three days after ischemia, a border zone adjacent to the infarcted area consisting of apoptotic macrophages was recognized. A novel finding was the appearance of apoptotic cardiomyocytes in the isolated perfused ischemic heart. Occurring as early as 50 min after the onset of ischemia, a high apoptotic index was present adjacent to the ligature placed around the coronary artery. This observation provides the opportunity to selectively examine factors leading to apoptosis in the ischemic heart under controlled experimental conditions.     

Morphine-potentiated platelet aggregation in in vitro and platelet plug formation in in vivo experiments

The detailed mechanisms underlying morphine-signaling pathways in platelets remain obscure. Therefore, we systematically examined the influence of morphine on washed human platelets. In this study, washed human platelet suspensions were used for in vitro studies. Furthermore, platelet thrombus formation induced by irradiation of mesenteric venules with filtered light in mice pretreated with fluorescein sodium was used for an in vivo thrombotic study. Morphine concentration dependently (0.6, 1, and 5 microM) potentiated platelet aggregation and the ATP release reaction stimulated by agonists (i.e., collagen and U46619) in washed human platelets. Yohimbine (0.1 microM), a specific alpha(2)-adrenoceptor antagonist, markedly abolished the potentiation of morphine in platelet aggregation stimulated by agonists. Morphine also potentiated phosphoinositide breakdown and intracellular Ca(2+) mobilization in human platelets stimulated by collagen (1 microg/ml). Moreover, morphine (0.6-5 microM) markedly inhibited prostaglandin E(1) (10 microM)-induced cyclic AMP formation in human platelets, while yohimbine (0.1 microM) significantly reversed the inhibition of cyclic AMP by morphine (0.6 and 1 microM) in this study. The thrombin-evoked increase in pH(i) was markedly potentiated in the presence of morphine (1 and 5 microM). Morphine (2 and 5 mg/g) significantly shortened the time require to induce platelet plug formation in mesenteric venules. We concluded that morphine may exert its potentiation in platelet aggregation by binding to alpha(2)-adrenoceptors in human platelets, with a resulting inhibition of adenylate cyclase, thereby reducing intracellular cyclic AMP formation followed by increased activation of phospholipase C and the Na(+)/H(+) exchanger. This leads to increased intracellular Ca(2+) mobilization, and finally potentiation of platelet aggregation and of the ATP release reaction.