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鼓槌石斛的资源现状与保护利用研究 总被引:1,自引:0,他引:1
目的:调查鼓槌石斛野生及栽培资源现状,为鼓槌石斛资源的可持续利用提供对策。方法:查阅文献,走访与实地调查相结合的方法。结果:由于过度采挖和生态环境的变化,鼓槌石斛野生资源破坏严重。鼓槌石斛人工栽培已经初具规模,以普洱地区面积最大。采收主要部位由老茎转变为鲜花,随着鲜花产品的开发利用,市场前景较好。结论:建议加大保护野生鼓槌石斛资源的力度,提高人工栽培鼓槌石斛质量。 相似文献
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降解性细菌对菲诱导的蛋白及酶活性应答反应 总被引:4,自引:0,他引:4
测定了3株以菲为唯一碳源的芽孢杆菌属(Bacillus)菌株(BA11、BA19和BA27)的降解能力、多酚氧化酶和过氧化氢酶的活性及蛋白变化.结果表明,当菲浓度在200mg·L^-1以下时,3株菌多酚氧化酶和过氧化氢酶的活性随菲浓度的提高变化不大,其中BA19和BA27菌株表现出较高的稳定性.当菲浓度为200mg·L^-1时,BA27诱导表达了一条分子量为27000道尔顿的新蛋白条带,同时有些蛋白的合成受到抑制.因此可以认为,诱导产生的新蛋白与其污染条件下的细菌降解能力及稳定性有关. 相似文献
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短期菲胁迫对大豆幼苗超氧化物歧化酶活性及丙二醛含量的影响 总被引:23,自引:3,他引:23
研究了不同浓度(0-200μg.g^-1)菲胁迫和恢复培养后大豆幼苗生长、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量的变化.结果表明,200μg.g^-1菲处理5d后大豆幼苗生长受到抑制,但幼苗恢复培养后经短暂停滞期后仍可恢复生长.菲污染对大豆幼苗SOD活性变化的剂量—效应关系的作用形式比较复杂,胁迫2d时为线性关系,胁迫5d和8d时为抛物线型.在菲处理前期(2d),幼苗SOD活性被100和200μg.g^-1菲显著诱导[分别为对照的1.15倍(P<0.05)和1.26倍(P<0.01)].菲暴露8d时,SOD活性显著降低,200μg.g^-1菲处理组SOD活性为对照的88%(P<0.05).菲处理5d后恢复培养2d和4d,50和100μg.g^-1菲处理组幼苗SOD活性得到恢复,而200μg.g^-1菲处理组幼苗SOD活性仍明显高于对照(P<0.05).试验亦反映出,100和200μg.g^-1菲处理5d和8d,幼苗MDA含量均比对照显著增加(P<0.05和P<0.01).可以认为,SOD活性可作为大豆幼苗遭受短期菲胁迫的生物标记物. 相似文献
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海南石斛化学成分研究 总被引:1,自引:0,他引:1
为了解海南石斛(Dendrobium hainanense Rolfe)的化学成分,采用色谱技术从海南石斛茎叶中分离得到14个化合物,经波谱分析分别鉴定为:2,6-二甲氧基对苯醌(1)、(+)-dehydrovomifoliol(2)、blumenol A(3)、2,7-二羟基-3,4-二甲氧基-9,10-二氢菲(4)、2,7-二羟基-3,4-二甲氧基菲(5)、3,7-二羟基-2,4-二甲氧基菲(6)、3-羟基-2,4,7-三甲氧基-9,10-二氢菲(7)、3-羟基-2,4,7-三甲氧基菲(8)、3,4,7-三羟基-2-甲氧基菲(9)、3,7-二羟基-2,4-二甲氧基-9,10-二氢菲(10)、(+)-lyoniresinol(11)、丁香脂素(12)、denchrysan A(13)和nobilone(14)。这些化合物均为首次从海南石斛中分离得到。活性测试结果表明化合物4~6、8~9、11和14对乙酰胆碱酯酶有抑制活性。 相似文献
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采用硅胶和凝胶柱色谱,以及制备性薄层色谱等多种分离手段,从盘龙参全草中分离得到了2个新的9,10-二氢菲类化合物,运用NMR和MS等波谱技术分别鉴定为4-羟基-2-甲氧基-8-呋喃[4′,5′:7,8]-9,10-二氢菲(1),4-羟基-2-甲氧基-8-{2',2'-二甲基吡喃[5',6':7,8]}-9,10-二氢菲(2). 相似文献
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从兰州某化工厂石油废水中分离筛选出1株高效降解菲的细菌F-1并对其菌种进行鉴定,结合紫外分光光度法及气相色谱-质谱联用(GC-MS)对菌株生长特性、不同烃类化合物降解特性及菲降解动力学等进行了研究,利用PCR技术检测了芳香烃代谢相关基因。结果表明,菌株F-1属于约翰逊不动杆菌(Acinetobacter johnsonii),可在终浓度为50~800 mg/L的含菲基础培养基中正常生长。在温度30℃、pH 7. 0、盐度0. 3%(质量分数)、转速180 r/min条件下培养5 d后菲(终浓度为100 mg/L)降解率为43. 57%,降解过程符合一级动力学特征。菌株F-1也能利用联苯、萘、蒽、芘为唯一碳源生长。GC-MS分析显示菌株对C10-C28部分直链烷烃具有较强的降解能力。PCR扩增结果表明,菌株F-1基因组中存在邻苯二酚-1,2-双加氧酶、苯甲酸盐双加氧酶、铁氧化还原蛋白还原酶、乙醇脱氢酶、二羟酸脱水酶、醛缩酶和氧化还原蛋白基因。研究结果为该菌株应用到含菲废水及多环芳烃污染土壤的处理和深度修复研究提供参考。 相似文献
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Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis
It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis. 相似文献
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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera. 相似文献
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted. 相似文献
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肝癌中HBV和HCV基因和抗原的分布及意义 总被引:1,自引:0,他引:1
采用原位分子杂交方法检测HCV
RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV
RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV
RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV
X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV
C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细 相似文献
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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献