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结核分枝杆菌滤过型的初步研究 总被引:2,自引:0,他引:2
朱明利 《中国微生态学杂志》2007,19(6):512-513,515
目的研究结核分枝杆菌滤过型的生物学特性与检测方法。方法菌阴肺结核患者的结核分枝杆菌及其L型的液体培养物经0.45μm滤膜过滤后,涂片观察细菌形态,滤液分别进行分枝杆菌及其L型培养,并采用荧光基因定量法进行结核菌DNA检测。培养物用免疫组化染色鉴定,并采用透射电镜观察。结果30例痰、血滤前、滤后FQ-PCR检测同时阳性为53%,同时阴性为13%,滤前、滤后FQ-PCR结果符合率为67%。滤过后液体培养9例涂片见少许抗酸颗粒或椭圆性球菌。透射电镜见细胞壁缺失的"致密体"样细菌和细胞壁缺如菌。结论菌阴肺结核痰及血培养物中存在结核菌滤过型,滤过型携带遗传信息并可自我复制,采用生物学方法可以对其进行检测。 相似文献
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山东济阳坳陷二叠纪孢粉组合 总被引:1,自引:0,他引:1
为了划分对比地层,确定地层层位,对济阳地区油气勘探钻孔曲古2、曲古3、义136中的孢粉样品进行了分析,其中5块样品含有孢粉化石,分别是曲古23(2843.2m)、义1365(3772.6m)、曲古334(4059m)、曲古323(4041m)和曲古313(4013m)。通过分析鉴定,共鉴定出59属,119种和未定种,根据样品中孢粉成分和含量的变化,建立了如下三个孢粉组合,自下而上为:Ⅰ.Cyclogranisporites Granulatisporites Laevigatosporites组合(山西组下部),Ⅱ.Punctatisporites Cyclogranisporites Florinites组合(山西组上部),Ⅲ.Macrotorispora Vesicaspo ra Pteruchipollenites组合(上石盒子组)。通过与华北、华南部分地区对比,确定各孢粉组合的地质时代为早二叠世中期(组合Ⅰ和组合Ⅱ),晚二叠世早期(组合Ⅲ)。由于含孢粉样品较少,层位不连续,其中下石盒子组孢粉组合未建立,有待于进一步研究。 相似文献
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从不同类型的石油中分离微体化石时,由于浸解材料的特性,使我们不得不放弃石油孢粉学中通用的浸解法。譬如:用氢氟酸及其它酸处理重液中的坚硬沉积物来代替分馏,可导致矿物成分更充分的溶解及孢粉材料的集中。在后过滤阶段,即对石油残渣中的样品的坚硬部分完成清洗时,对高粘性乳化石油和高石蜡化石油来说,必须改变用浸解方法。石油中由于存在高含量的含水乳化剂的石蜡和沥青物质,导致形成坚固的、很难破坏的乳胶体。 相似文献
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吉林省敦化地区晚全新世泥炭沼泽孢粉组合特征及古植被 总被引:2,自引:0,他引:2
对大桥泥炭地的孢粉进行了分析和年龄测定.根据孢粉组合、地层特征和14C年龄将剖面划分为4个孢粉带,分别为2 195±70~2 045±70 yr B.P.松为主的松-云冷杉-榛-栎-苔草组合带、2 045±70~1 745±70 yr B.P.苔草为主的松-桦-榛 胡桃-苔草组合带、1 745±70~705±70 yr B.P.松-榛-鹅耳枥-苔草-毛茛组合带和705±70 yr B.P.~1 950 yr A.D.松-云冷杉-桦-苔草组合带.周围植被由温带山地针叶林(类似现今海拔1 100 m以上)、温带针阔混交林下部(类似现今海拔400~600 m)和温带针阔混交林中部(类似现今海拔600~800 m)过渡到温带针阔混交林上部(类似现今海拔800~1 100 m).相应地,泥炭沼泽经历了孕育期、蓬勃发展期、继续扩张期和消亡期. 相似文献
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通过对河北省文安洼湿地沉积物孢粉组合特征、粒度的综合分析,重建了该地区晚全新世以来气候环境变化过程。研究结果表明,该地区晚全新世以来气候总体由凉湿转变为冷干,具体可以分为3个阶段:3 200-2 010cal.a B.P.以湿润气候为主;2 010-1 280cal.a B.P.气候偏冷干;1 280cal.a B.P.以来气候进一步冷干。小冰期以来(556-160cal.a B.P.),中华卷柏孢子持续高含量,伴随粗颗粒物质63μm含量的上升,表明小冰期以来,文安洼流域气候波动较大,雨水、干旱、洪水并存。 相似文献
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目的通过探索F型肉毒梭菌培养液可滤性实验,为现有生产工艺提供科学的优化方案。方法分别采用不同型号的过滤器,通过不同的过滤组合对F型肉毒梭菌培养液进行澄清过滤。结果采用K700P过滤器(过滤精度6.0~15.0μm)对F型肉毒梭菌培养液进行一级澄清过滤,采用50P过滤器(过滤精度0.5~0.85μm)对料液进行二级澄清过滤,对F型肉毒梭菌培养液具有良好的澄清效果。结论可滤性实验的探索对于F型肉毒梭菌培养液批生产量的扩大具有切实可行的指导意义。 相似文献
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利用扫描电镜对中国产叉蕨科7属34种植物孢子的形态进行了观察。叉蕨科植物孢子为左右对称,极面观为椭圆形,赤道面观为半圆形、超半圆形或豆形;极轴长为18~38μm,赤道轴长为23~57μm;单裂缝,裂缝长度为孢子全长的1/2~2/3;孢子具脊状、翅状、刺状和耳状4种纹饰,孢子表面有时具细刺、颗粒或孔。通过孢粉学分析,叉蕨科依据孢子形态特征和依据孢子体形态特征的分类结果并不一致,孢粉纹饰类型呈现一定程度的属间交叉;支持将叉蕨科和鳞毛蕨科进行重新划分的MAARTEN J.M的新分类系统。 相似文献
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目的:研究一种可以控制三维细胞支架内部孔隙结构的实验技术,用于制备孔隙结构可控的三维细胞支架,以满足组织工程对支架孔隙结构的要求。方法:均匀混合粘结剂与致孔剂,在离心力作用下去除混合物中多余的粘结剂,应用溶剂浇注/颗粒沥析方法制备三维细胞支架。结果:致孔剂粘结块的结构非常均匀,粘结程度可以通过实验条件控制。例如,直径为100~220μm的致孔剂,在离心力为161g,粘结剂浓度分别为20%和40%时,颗粒间粘结程度分别为33.78±556 (134)μm和42.89±5.87 (132) μm。并且,利用该技术制备的三维多孔支架,其内部孔隙大小取决于致孔剂颗粒大小,孔隙间的通道直径取决于致孔剂的粘结程度,即离心粘结与溶剂浇注/颗粒沥析技术相结合,能够方便地控制三维支架的孔隙结构。例如,当粘结程度为33.78±556 (134) μm时,支架的通道直径为33.34±5.21(12)μm,两者之间无显著差异。 结论:利用离心粘结与溶剂浇注/颗粒沥析技术结合,获得了孔隙呈球形、孔隙间完全连通的、结构均匀的大体积三维细胞支架,并且支架的孔隙以及孔隙间通道大小均可以实现人为控制。 相似文献
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本文报道亚洲小车蝗痘病毒感染黄胫小车蝗引起的病理学变化.该病毒主要感染寄主脂肪体,其次为血细胞.球状体有3种类型:大球体、椭球体和小球体,大小分别为30.41μm×25.40μm、6.58μm×4.78μm和3.35μm×2.60μm.病毒粒子为椭球形,大小为230 nm×176 urn,囊膜表面具有球状亚单位,直径为16nm,使病毒粒子看上去似桑椹,侧体为圆筒形,髓核内绳索状物质似有2折,在横切面上是2个圆点.病毒粒子的发育包括以下4个主要阶段:病毒发生基质的产生;球状颗粒的形成;内核和侧体的分化;髓核和衣壳的进一步分化.成熟病毒粒子逐渐包入球状体.该病毒可感染同属蝗虫. 相似文献
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氨基化二氧化硅颗粒固定木瓜蛋白酶研究 总被引:11,自引:2,他引:9
采用正硅酸乙酯与N-(β-氨乙基)氨丙基三乙氧基硅烷在油包水形成的微胶囊中同步水解的方法,一步法制备了氨基化的二氧化硅颗粒,得到的颗粒粒径在0.3~0.5μm之间,平均大小为0.37μm, 氨基含量和颗粒大小可控,氨基含量高达56mmol/g。此颗粒经戊二醛处理后,采用共价法固定木瓜蛋白酶,固定化最适pH6.5,最佳给酶量为15mg/g载体,固定化酶的最适反应温度为70℃,最适反应pH为6.5,固定化酶热稳定性,pH耐受性,贮存稳定性都明显高于游离酶,表明此颗粒可作为一种优良的酶固定化载体。 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