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1.
本文记了分别采自云南高黎贡山的栅蛛科栅蛛属Hahnia 2新种:垭口栅蛛,新种S.yakouensis sp.nov.和肾形栅蛛,新种S.reniformis sp.nov..垭口栅蛛后眼列前曲,交媾腔大,扁圆形,交媾孔1个,位于交媾腔下缘,交媾管粗,呈"人"字形下行分成2支再向两侧扭曲.纳精囊有一肓管斜向上伸出,鉴于上述特征而与Hahnia mridulae Tikader,1970不同.肾形栅蛛交媾孔2个,位于生殖厣腹面中央,纳精囊1对,大,肾形,插入器始于生殖球左下方,鉴于上述特征而与Hahnia xinjiangensis Wang et Liang,1989不同. Abstract: The present paper deals with two new species of the genus Hahnia collected from the Gaoligong Mountains Region of Yunnan Province, China: Hahnia yakouensis sp. nov., Hahnia reniformis sp. nov..  相似文献   

2.
中国医科大学博士后科研流动站始建1995年。目前学校设有基础医学、临床医学和生物学3个博士后科研流动站。但由于每年国家财力有限,资助名额很少,在有限条件下建立、健全博士后制度,加强对博士后人员的培养,调动博士后人员的积极性是一项重要的研究课题。  相似文献   

3.
遗传物质的发现者之一——麦卡锡   总被引:1,自引:0,他引:1  
1944年,3位科学家艾弗里、麦卡锡和麦克劳德在DNA遗传本质方面的发现是20世纪最重要的发现之一,这个发现打开了生物学革命的大门,从而改变了人类对自然界的看法,这项研究还为1953年沃森和克里克DNA双螺旋结构的发现奠定了坚实的基础,但不幸的是3位科学家都未曾荣获诺贝尔奖.通过介绍麦克林·麦卡锡的科学研究,从而对这项发现的基本状况有一个基本的了解.  相似文献   

4.
《植物分类学报》2008,46(3):237-238
One and half centuries ago, Charles Darwin (1859) presented overwhelming evidence and argued that all life on the earth shared common descent, and "from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved". Ernst Haeckel (1886) and several of his contemporaries attempted to trace the pattern of descent among all extant and extinct forms in what Darwin referred to as "the great Tree of Life". Ever since then, systematists and evolutionary biologists have been exploring morphological, cytogenetic, chemical, developmental and molecular characters, and actively developing theories and methods to infer phylogenetic relationships among organisms from these characters. This endeavor has been especially stimulated by the rise of molecular biology and the emergence of computer science over the past 50 years. At the beginning of the 21st century, we are presented with an unprecedented opportunity to reconstruct the entire Tree of Life, and further, to study evolutionary processes and mechanisms in the context of a robust phylogenetic framework.  相似文献   

5.
青宁生 《微生物学报》2008,48(3):I0001-I0002
魏曦,字东升,1903年12月25日出生于湖南岳阳一个小职员家庭,父亲任职于邮政局.1914~1921年他在家乡湖滨中学读书,毕业后考入长沙湘雅医学院,学习两年后曾参加北伐军,任第四集团军警卫团三等军医.后退出军队,在长沙广雅中学任教.1928年入设立在上海的中央大学医学院(1932年独立为上海医学院)学习,1933年毕业,获博士学位.  相似文献   

6.
高黎贡山北段东西坡种子植物区系的比较研究   总被引:2,自引:0,他引:2  
高黎贡山北段的东西坡由于在降雨量和热量分配等方面存在着显著的差异,致使东西坡在植物的种类、组成及区系特征等方面表现出明显的差异.东坡记载野生种子植物152科,580属,1475种及192变种(亚种),西坡记载野生种子植物162科,659属,1804种及186变种(亚种).东西坡种子植物科、属、种的对比分析表明:1)东西坡现代种子植物区系具有相同的历史渊源,但其区系联系减弱了,东西坡区系相似性程度,依科、属、种的顺序依次递减;2)西坡现代种子植物区系比东坡具有更为深刻的热带起源烙印.就科、属、种三个水平来说,东坡的热带成分低于西坡,温带成分高于西坡.许多典型的泛热带大科在西坡比东坡有着更为丰富的种类,其中有些泛热带科分子在东坡缺乏分布,而在西坡找到了合适的驻留之地;3)西坡现代种子植物区系与东喜马拉雅植物区系的联系比东坡紧密,而东坡与高黎贡山以东的区系联系比西坡密切,由于高黎贡山山脉的阻隔,近代植物物种的东西坡交流发生了障碍;4)西坡生态地理环境比东坡更有利于物种的生存、繁衍和分化,它既是古老成分的避难所,又是孕育新生成分的摇篮.  相似文献   

7.
8.
每年有大量来自工业、农业、养殖业和城市污水处理厂的废水被排入到水环境中,因此,地球上的水环境面临大量来自生活废水、工农业废水、非法排放的废水及其它废水的污染物质(如抗生素、杀虫剂,除草剂、烃等)的严重挑战,特别是近年来随着集约化养殖的发展,废水污染问题日益突出,并且随着分析手段的进步,能够检测到被排入水环境中的化学污染物质也越来越多,这些化学污染物对水环境中的生物产生有害影响.但是,微生物在污染控制上具有许多重要的作用.因此,本文对微生物在水环境污染物降解中的应用进行了评论.结果表明微生物主要是应用在水产养殖水中,而在其它的水体系(如河、湖、海)的应用较少.  相似文献   

9.
Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to reconstruct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets are congruent in that the genera Prunus s.l. and Maddenia form a monophyletic group, with Maddenia nested within Prunus. However, the ndhF data set is incongruent with the ITS data supporting two major groups within Prunus one consisting of subgenera Laurocerasus (including Pygeum) and Padus as well as the genus Maddenia and another of subgenera Amygdalus, Cerasus, and Prunus. The ITS data, on the other hand, support a clade composed of subgenera Amygdalus and Prunus and Prunus sect. Microcerasus in addition to a paraphyletic grade of subgenera Laurocerasus and Padus (and the genus Maddenia) taxa. In general, the subgeneric classifications of Prunus s.l. are not supported. The ITS and ndhF phylogenies differ mainly in interspecific relationships and the relative position of the Padus/Laurocerasus group. Both ITS and ndhF data sets suggest that the formerly recognized genus Pygeum is polyphyletic and that the distinction of the subgenera Padus and Laurocerasus is not supported. The biogeographic interactions of the temperate and tropical members in the Padus/Laurocera- sus/Maddenia alliance including Pygeum are shown to be highly dynamic and complex.  相似文献   

10.
2007年10月13日至11月5日进行敦煌市湿地鸟类调查时,分别在南湖湿地与候鸟自然保护区及党河水库使用Leica apo77高倍望远镜观察到3种水鸟,在以往的文献资料中未见其分布于甘肃的报道,应为甘肃鸟类新纪录。笔者用500mm镜头分别拍下3种水鸟的照片。1.赤颈(Podiceps grisegena)2007年10月13日13:30时,在南湖湿地与候鸟自然保护区的阳关水库(渥洼池)记录到2只赤颈。当时水面上同时有凤头(P.cristatus)、黑颈(P.nigricollis)以及大量鸭类、潜鸭类游禽活动,赤颈体形较凤头小,而又明显比黑颈大。其中一只赤颈的…  相似文献   

11.
黑色素合成是桦褐孔菌Phaeoporus obliquus次生代谢过程中的一个重要事件。黑色素的过多合成势必影响其他酚类的积累。本文以茉莉酸和双氧水为调控因子,开展了该突变体深层发酵过程酚类化合物积累研究。正常培养条件下,每升发酵液积累酚类化合物最高可达317.45mg/L,其中包括苯甲酸衍生物(45.3mg/L),黄酮苷元(74.4mg/L),黄酮苷(160mg/L)以及硬毛素类化合物(18.5mg/L)。加入茉莉酸后,总酚最大值增加到620.45mg/L,其中苯甲酸衍生物增加到230.26mg/L,黄酮苷元增加到166.86mg/L,而黄酮苷和硬毛素类化合物却分别降低到98.5mg/L和7.1mg,双氧水的加入没有提高总酚的最大积累(315.69mg/L)。因此,与野生型相比,黑色素缺失使总酚的积累有所增加,随茉莉L酸的加入总酚积累最大值增加近一倍。虽然双氧水的加入提高了苯丙氨酸裂解酶活性,但总酚的积累却没有增加,这可能是由于一部分酚类化合物在抗双氧水氧化胁迫过程中被消耗。  相似文献   

12.
Zheng W  Zhang M  Zhao Y  Wang Y  Miao K  Wei Z 《Bioresource technology》2009,100(3):1327-1335
Phenolic compounds produced by sclerotia of Inonotus obliquus are the active constituents responsible for antioxidant activities. In this study, I. obliquus was grown in a continuously stirred tank reactor (CSTR) to explore how it accumulates phenolic compounds in different culture media and whether these compounds possess antioxidant activities. Phenolic compounds produced by I. obliquus in the control medium consisted of melanins, flavonoids, polyphenols and small phenolics. Their accumulation was affected by adding H(2)O(2) to the medium, where increased levels of total intracellular phenols (TIP) and melanins, but less total extracellular phenol (TEP) occurred. Simultaneous exposure to H(2)O(2) and arbutin resulted in a further increase in TIP production and reduced accumulation of TEP. Both TIP and TEP obtained at different culture ages and media were active in scavenging superoxide anion and DPPH radicals. Therefore, production of phenolic compounds by I. obliquus is enhanced by imposing oxidative stress, which might allow it to be exploited as a reliable source of pharmaceutically important phenolic compounds.  相似文献   

13.
Inonotus obliquus (Fr.) Pilat is a white rot fungus belonging to the family Hymenochaetaceae in the Basidiomycota. In nature, this fungus rarely forms a fruiting body but usually an irregular shape of sclerotial conk called ‘Chaga’. Characteristically, I. obliquus produces massive melanins released to the surface of Chaga. As early as in the sixteenth century, Chaga was used as an effective folk medicine in Russia and Northern Europe to treat several human malicious tumors and other diseases in the absence of any unacceptable toxic side effects. Chemical investigations show that I. obliquus produces a diverse range of secondary metabolites including phenolic compounds, melanins, and lanostane-type triterpenoids. Among these are the active components for antioxidant, antitumoral, and antiviral activities and for improving human immunity against infection of pathogenic microbes. Geographically, however, this fungus is restricted to very cold habitats and grows very slowly, suggesting that Chaga is not a reliable source of these bioactive compounds. Attempts for culturing this fungus axenically all resulted in a reduced production of bioactive metabolites. This review examines the current progress in the discovery of chemical diversity of Chaga and their biological activities and the strategies to modulate the expression of desired pathways to diversify and up-regulate the production of bioactive metabolites by the fungus grown in submerged cultures for possible drug discovery.  相似文献   

14.
本文研究了不同条件下深层培养的斜生褐孔菌Phaeoporus obliquus与野生桦褐孔菌在酚类化合物组成及其含量上的差异以及对铅处理小鼠常压缺氧和游泳耐力影响。野生桦褐孔菌主要含有水溶性黑色素、硬毛素衍生物,两者各占总酚类化合物的12.1%和42.2%。而深层培养的桦褐孔菌则主要积累黄酮类化合物,其中正常生理条件下积累量达到总酚的35.5%,加入H2O2后积累量达到总酚的92.5%,同时加入H2O2和熊果苷后则为总酚的76.9%。正常培养基中水溶性黑色素的积累量达到总酚的20.2%,而加入H2O2或同时加入H2O2和熊果苷后水溶性黑色素则很少合成。口服野生斜生褐孔菌或不同条件下深层培养的斜生褐孔菌酚类化合物都能使铅处理小鼠忍耐缺氧和游泳的时间延长12–15min。同时,口服不同来源的斜生褐孔菌酚类化合物可提升铅处理小鼠外周淋巴细胞的活力和总超氧化物歧化酶活性,并降低丙二醛的积累。因此,斜生褐孔菌酚类化合物对铅处理小鼠耐缺氧和游泳的提升作用在于抑制了脂质过氧化反应,增强了过氧化物歧化酶的表达,从而保护了铅处理小鼠的细胞和器官免于氧化胁迫的损伤。  相似文献   

15.
本研究探讨了NO对深层培养的桦褐孔菌积累抗氧化酚类化合物的影响。在桦褐孔菌的培养基中分别加入0.01mmol/L、0.1mmol/L以及1mmol/L的NO供体硝普钠,并测定总酚的含量及其抗氧化活性。发酵产物的抗氧化活性以清除DPPH和羟自由基活力表示。加入0.1mmol/L的硝普钠可使桦褐孔菌胞内外酚类化合物分别达到最高水平67mg/g和677mg/L。不同培养时期产生的胞内外酚类化合物都具有抗氧化活性,尤其是添加0.1mmol/L硝普钠的菌丝体。因此NO可用于上调深层发酵培养的桦褐孔菌酚类化合物的积累。  相似文献   

16.
作者旨在阐明真菌激发子对桦褐孔菌多酚积累的影响。以摇瓶法培养桦褐孔菌,在其培养液中加入真菌激发子和一氧化氮合酶抑制剂氨基胍,观察桦褐孔菌多酚和一氧化氮的积累并测定菌丝体内一氧化氮合酶和苯丙氨酸解氨酶的活性。多酚以Folin-Ciocalteu法测定,一氧化氮的积累量用硝酸还原酶法测定,一氧化氮合酶和苯丙氨酸解氨酶活性均以分光光度计法测定。结果表明,添加45μg/mL的激发子可使桦褐孔菌菌丝体多酚的积累量达到46.5mg/g,显著地高于正常培养的菌丝体多酚积累量34.6mg/g;同时加入45μg/mL的激发子和10mmol/L氨基胍则使菌丝体多酚积累的最高水平降为34.8mg/g。此外,激发子的加入显著促进了一氧化氮的产生并提高了苯丙氨酸解氨酶活性,而这种促进和提升作用为氨基胍所抑制。这表明真菌激发子能显著地提升桦褐孔菌多酚类化合物的积累,而一氧化氮可能是这种提升作用的信号传导分子。  相似文献   

17.
采用基于核磁共振代谢组学的方法研究了两株地理隔离的桦褐孔菌中国牡丹江菌株(IOM)和芬兰万塔菌株(IOV)在深层培养过程中主要代谢产物组成的差异。IOM和IOV两菌株在培养过程中积累菌丝体生物量、菌丝体酚类(TMP)以及三萜化合物(TMT)的过程相似,但IOM菌株产生较高水平的TMP。代谢产物组成动力学比较结果表明,IOM在第3天含有较高水平的硬毛素类似物、桦褐孔菌二糖和TMT,但在第5天均有所下降。导致这些差异的代谢产物为fuscoparianolD,21,24-羊毛甾-7,9(11),23-三烯-3β,22,25-三醇,羊毛甾-8,23-二烯-3β,22,25-三醇,23,24-环戊羊毛甾-3β,21,25-三醇-8-烯,桦褐孔菌二糖,phelligridinsC,D及H,甲基地花菌素A和C,地花菌素B,davallialactone及methyl davallialactone。这些代谢产物在IOV的提取物中均参与清除自由基,而在IOM的提取物中主要是酚类化合物参与自由基的清除。两菌株的这些差异反应了环境条件对桦褐孔菌生长及代谢的影响,即不仅影响其次生代谢产物的合成,还影响代谢产物在防止细胞氧化损伤过程中所起的作用。  相似文献   

18.
Melanin complex of the fungus Inonotus obliquus   总被引:6,自引:0,他引:6  
The fungus Inonotus obliquus (Pers.) Pil. synthesised high-molecular-weight phenolic pigments that were assigned to melanins according to their physicochemical properties. It was showed that copper ions (0.008%), pyrocatechol (1.0 mM), and tyrosine (20.0 mM) stimulated the melanogenesis. The production of melanin correlated with the synthesis of o- and p-diphenoloxidases. The fungal melanin had strong antioxidant and genoprotective effects.  相似文献   

19.
This study was designed to investigate the light effect on biosynthesis of antioxidant phenolic compounds by Inonotus obliquus grown in submerged cultures using 1H NMR spectroscopy combining multivariate pattern recognition strategies. I. obliquus were exposed to a range of light conditions and resultant data were compared to those from field-grown sclerotia and the mycelia grown in daylight. Daylight illumination inhibited biosynthesis of davallialactone and phelligridins and other hispidin analogs. Continuous darkness enhanced the formation of phelligridins, davallialactone and inoscavins. Phelligridins and davallialactone also occurred in the mycelia grown in blue and red light with levels lower than those found in darkness. In addition, polyphenols synthesized under daylight conditions showed less potential antioxidant activity than those determined with other light regimes. These findings demonstrate that light regulates biosynthesis of polyphenols in I. obliquus and their subsequent antioxidant activities, and 1H NMR-based metabolic profiling is a cost-effective approach for evaluating light effects on fungal metabolisms.  相似文献   

20.
While Inonotus obliquus produces a diverse range of bioactive metabolites in its natural habitats, it accumulates less in its submerged cultures. We show here that coculture of I. obliquus with Phellinus punctatus resulted in less production of mycelial biomass but an increased accumulation of phenolic compounds, melanins, and lanostane-type triterpenoids. Metabolites increased in production by coculture include phelligridin C, phelligridin H, methyl inoscavin A, inoscavin C, inoscavin B, davallialactone, methyl davallialactone, foscoparianol D, 21,24-cyclopentalanosta-3β,21,25-triol-8-en, lanosta-7,9(11),23-triene-3β,22,25-triol, and inotodisaccharide and melanins. Metabolites from coculture also showed an increased potential for scavenging free radicals and inhibiting the proliferation of HeLa 229 cells. Davallialactone, methyl davallialactone, and minor phenolic components are the major contributors for scavenging DPPH and hydroxyl radical in monoculture, and phelligridin C, phelligridin H, methyl inoscavin A, inoscavin C, methyl davallialactone, foscoparianol D, and inotodisaccharide are those for scavenging the tested radicals in coculture. Lanostane-type triterpenoids indicated limited roles in scavenging free radicals. Nearly all the detected metabolites correlate positively with inhibiting proliferation of HeLa 229 cells. Thus, coculture of I. obliquus with other fungi seems to be a cost-effective strategy for upregulating biosynthesis of bioactive metabolites.  相似文献   

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