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1.
尖端赛多孢子菌(Scedosporiumapiospermum)即波氏假阿利什菌的无性型,是一种侵袭性较强的条件致病菌。1病因和发病机制尖端赛多孢子菌广泛分布于各种自然材料中,如沼泽、湿地、污水、腐物、咸水等。尖端赛多孢子菌感染多发生于艾滋病、器官移植、淋巴瘤、白血病、长期应用糖皮质激素或免疫抑制剂等免疫功能缺陷患者,也可发生于免疫功能正常者,如外伤、污水淹溺、HELLP综合征等。  相似文献   

2.
目的对23株分子鉴定为赛多孢霉复合种的菌株检测其对伏立康唑、泊沙康唑、伊曲康唑和两性霉素B的敏感性。方法参照美国临床实验室标准化研究所制定的M38-A2方案,检测临床来源的9株波氏假阿利什霉(Pseudallescheria boydii)、6株P.ellipsoidea、1株P.angusta、1株P.fusoidea和6株尖端赛多孢(Scedosporium apiospermum)对伏立康唑、泊沙康唑、伊曲康唑和两性霉素B的MIC值。结果伏立康唑对所有受试菌株的MIC值为0.25~1μg/m L,泊沙康唑为2~4μg/m L。伊曲康唑对P.ellipsoidea、尖端赛多孢的MIC值为2~16μg/m L,对波氏假阿利什霉、P.angusta、P.fusoidea的MIC值为2~4μg/m L。两性霉素B对5种菌的MIC值均为为4~16μg/m L。结论伏立康唑、泊沙康唑、伊曲康唑和两性霉素B对波氏假阿利什复合种中不同种的敏感性未见明显差异。该复合种对伏立康唑最敏感,泊沙康唑其次,伊曲康唑变化较大,两性霉素B的效果最差。  相似文献   

3.
目的报道5例丝状真菌所致真菌性鼻窦炎病例。方法分析5例鼻窦炎患者临床资料,对患者鼻分泌物或鼻黏膜进行真菌直接镜检和培养,对培养获得菌株进行形态学和分子生物学鉴定。结果结合真菌直接镜检、培养和分子生物学方法,确定致病真菌为茄病镰刀菌、烟曲霉、黄曲霉、波氏假阿利什霉和萝卜镰刀菌。4例患者采用鼻内窥镜手术治疗,1例患者采用伏立康唑、两性霉素B控制病情,效果均良好。结论真菌性鼻窦炎致病真菌多样,分子生物学可做准确鉴定,鼻内镜手术治疗效果良好。  相似文献   

4.
白假丝酵母菌属于临床侵袭性条件致病菌,可引起从浅表黏膜到危及生命的全身感染性疾病,其形成的生物膜是为生物膜内细胞提供结构支架和保护模式的结构化菌体群落,其产生的滞留菌是一种随机且对抗真菌药物高度耐受的细胞亚群。由于生物膜与滞留菌两种因素的存在,致使临床治疗侵袭性真菌感染时面临极大挑战,因此,研究白假丝酵母菌滞留菌形成机制对目前临床治疗侵袭性真菌感染具有重要意义。本文对白假丝酵母滞留菌形成的主要调控因素(生物膜的形成、氧化应激反应、蛋白酶系统、TOR-RAS-CAMP-PKA信号转导途径和菌种自身因素),以及滞留菌与临床疾病的相关性进行综述。  相似文献   

5.
小肠结肠炎耶氏菌(Yersiniaenterocolitica)原为巴氏菌属,1972年将本菌与假结核菌和鼠疫一起列为Yersinia 菌属。V.ent 引起的疾病叫耶氏菌病是人畜共患的肠道传染病。据报导该菌分布世界各地。由于临床表现多样性,故常将耶氏菌病诊为急性阑尾  相似文献   

6.
假笼头菌属(Pseudoclathrus)是刘波和鲍运生(1980)根据模式种——柱孢假笼头菌(P.Cylindrosporus Liu et Bau)所建立的新属。 1987年,本文作者报道了雷公山假笼头菌(P.Leigonshancnsis Zhou et Zhang)一新种,本文再报道该属的另一新种——安顺假笼头菌Pseudoclathrus anshunensi Zhou et Zhang。本新种不同于柱孢假笼头菌之处主要是,新种具4条柱状臂,臂无脊沟,柄露于菌托外。而柱孢假笼头菌具6个柱状臂,每条臂均具纵脊沟,柄藏于菌托内;与雷公山假笼头菌的区别在于雷公山假笼头菌具5—6条薄带状的臂,臂肉桂色,担子果大,担孢子也较大,而新种具4条柱状臂,橙黄色,担子果和担孢子均较小。模式标本存放于贵州农学院植病教研组真菌标本室。  相似文献   

7.
张云霞  刘云龙 《菌物研究》2006,4(3):59-60,69
报道了葡萄上两个国内新记录真菌病害:由茶子小穴壳菌(Dothiorella ribis)引起的熟腐病和败育假蜜环菌(Armillariella tabescens)引起的根腐病。病害附有症状和病原菌的描述和形态图。  相似文献   

8.
从假蜜环菌培养物的乙醇提取物中分离得四种成分,其中之一为新的香豆素,定名为假蜜环菌甲素(Armillarisin A),为治疗胆囊炎的一种活性成分。分子式C12H10O5,熔点245—246℃,用紫外、红外光谱,质谱,核磁共振确定假蜜环菌甲素为3—乙酰基一5羟甲基一7一羟基香豆素。另一成分定名为假蜜环菌乙素,熔点162一163.5℃,分子式C9H10N2O3,用同样的方法初步测定了它的结构。  相似文献   

9.
刚地弓形虫引起的弓形虫病是一种严重危害人类健康的人兽共患寄生虫病,采用疫苗防治该病是当前研究的热点领域之一。MIC抗原是一种有效的疫苗候选分子,本研究综述了鼠伤寒沙门菌、卡介苗、格登链球菌、腺病毒血清型5和假狂犬病毒等载体介导的刚地弓形虫MIC疫苗的研制现状。  相似文献   

10.
假白喉棒杆菌(Corynebacterium pseudodiphtheriticum)是寄居于人体咽喉和鼻腔黏膜,以往认为是不产毒素、无致病的正常菌群.近来认识到少数能引起下呼吸道感染[1],但由该菌发生败血症十分少见,现从失代偿性肝硬化合关败血症患者血液中培养出该菌原菌及L型,报告如下.  相似文献   

11.
为研究油茶(Camellia oleifera A)嫁接时穗条和砧木创伤后内源激素动态变化规律,解析影响砧穗嫁接面愈合的生理机制,为油茶砧穗愈合生长机理提供理论支持。以树龄6年的长林18号和53号的穗条和实生砧木为材料,按照芽苗砧嫁接方法切割穗条S0(0 min)、S10(10 min)、S40(40 min)和砧木茎段Z0(0 min)、Z10(10 min)后,利用液质联用法(HPLC-MS)测定吲哚乙酸(IAA)、脱落酸(ABA)、反式玉米素(TZR)、玉米素(Zeatin)、水杨酸(SA)和茉莉酸(JA)含量,分析不同时间段内源激素变化及品种间差异的关系。结果显示:创伤后18号的TZR、Zeatin和SA含量总体高于53号;18号IAA、SA和JA逐渐下降;TZR和Zeatin分别在S10和S0达最高值后下降;ABA在S10达最高值。53号IAA和JA爱S10达最高值后下降;TZR、Zeatin和SA在S10达低值后逐渐上升;ABA在S0达高值后逐渐下降。砧木茎段创伤前后激素含量除JA外18号高于53号;两品种Z0时激素含量下降,Z10后上升,仅53号ABA和SA含量在Z0达高值后下降。砧木茎段和根部激素含量在品种间除JA外18号高于53号,茎段的IAA、ABA高于根部,其他激素为根部高于茎段。激素比值在品种间和部位间差异明显;IAA/ABA、IAA/TZR、IAA/Zeatin和IAA/JA、ABA/TZR、ABA/Zeatin和ABA/JA比值为53号高于18号;穗条内SA/IAA为18号高于53号,SA/JA和SA/ABA为53号高于18号;砧木茎段均为18号高于53号;TZR/SA、TZR/JA比值在穗条和砧木茎段为18号高于53号。两品种创伤后IAA与JA极显著正相关,而IAA与SA,SA与JA在18号极显著正相关,53号极显著或显著负相关;53号TZR、Zeatin、SA间极显著或显著正相关,JA与TZR、Zeatin和SA极显著负相关。砧木茎段创伤后18号激素间为极显著或显著正相关;53号TZR和Zeatin与IAA、JA极显著正相关,与SA存在显著负相关,SA与JA有显著负相关。砧木茎段和根部间品种间仅在SA与各激素间相关性存在差异,其他激素间存在极显著正相关或负相关。综上所述,砧穗创伤后激素水平上18号在创伤面易于愈伤组织发育,而53号抗逆激素水平较高且与细胞分裂增殖类激素负相关,可能影响53号嫁接后愈合生长;嫁接应在创伤后10 min内较为适宜;砧穗间激素含量及比值的差异可能会影响后期嫁接部位形态重建以及穗条生长。  相似文献   

12.
社鼠组织器官同工酶的研究   总被引:5,自引:0,他引:5  
傅必谦  袁虹 《兽类学报》1997,17(2):141-145
用聚丙烯酰胺凝胶等电聚焦电泳方法,分析了社鼠的肝、肾、心肌、骨骼肌、肺、脾和脑等多种组织器官的LDH、ADH、EST、和SOD4种同工酶,对各组织器官的酶带数目和分布,以及酶活性进行了比较研究。结果表明,社鼠的LDH同工酶、ADH同工酶和EST同工酶具有比较明显的组织特异性,而SOD同工酶的组织特异性较低。肺和脾除EST同工酶活性较高外,脑除LDH同工酶活性较高外,其它3种同工酶的活性均较低;而肝和肾中4种同工酶的活性普遍很高。心肌和骨骼肌因氧张力不同而使LDH同工酶酶谱存在明显差异,但其它3种同工酶酶谱却非常相似。同工酶的组织特异性与各组织器官所执行的生理功能是相一致的  相似文献   

13.
洪湖野菰及其化学成分分析   总被引:3,自引:0,他引:3  
野菰(Zizania latifolia)是湖北省洪湖中优势水生维管束植物,其群落占全湖355平方公里面积的127平方公里。茎和叶的年生物量为4379克鲜重/平方米,全湖总年产量121700吨干重,目前未被利用。野菰各器官的蛋白质和氨基酸含量分别以百分干重表示:根,7.0和4.76;根状茎,11.3和8.85;茎,9.5和7.15;嫩茎梢,22.4和16.53;叶,16.8和14.61。500克干叶的必需氨基酸含量接近100克干重草鱼幼鱼背肌的必需氨基酸含量。脂肪:叶中3.4~4.2,茎中2.2;粗纤维:叶中26.8~28,茎中24.2;灰分:叶中10.0,茎中5.8。菰茎含可溶性糖类30%以上,其中葡萄糖,果糖、蔗糖和麦芽糖是主要成分。结果表明野菰是一种优质饲料。  相似文献   

14.
Differential gene expression in the rat after injury of dorsal root ganglion neurons in vivo, and simulation injury of Schwann cells and oligodendrocytes in vitro was analyzed using high-density cDNA microarrays. The analyses were carried out to study the genetic basis of peripheral nerve regeneration, and to compare gene regulation in glia of the central (oligodendrocyte) and peripheral (Schwann cell) nervous systems. The genes showing significant differential regulation in the three study groups represented all aspects of cellular metabolism. However, two unexpected observations were made. Firstly, a number of identical genes were differentially regulated in activated Schwann cells, activated oligodendrocytes and regenerating DRG neurons. Specifically, a group of 113 out of 210 genes that were down-regulated in Schwann cells upon lipopolysaccharide (LPS) treatment, were identical to genes up-regulated in the injured, regenerating DRG. Furthermore, a group of 53 out of 71 genes that were down-regulated in interferon gamma (IFN-gamma)/LPS-activated oligodendrocytes, were identical to genes up-regulated in the DRG neurons. Finally, 22 genes were common to these three groups, i.e., down-regulated in activated oligodendrocytes, down-regulated in activated Schwann cells, and up-regulated in regenerating DRG neurons. Secondly, a group of 16 cell-cycle and proliferation-related genes were up-regulated in the DRG following sciatic nerve crush, despite the absence of cells undergoing mitosis in the DRG, or any significant presence of apoptosis-related gene expression. Therefore, it appears that in these three cell types, large sets of genes are reciprocally regulated upon injury and/or activation. This suggests that the activation of the injury-related gene expression program in cell derivatives of the neuroectoderm involves, in part, highly conserved genetic elements.  相似文献   

15.
S. Xie  Y. Cui    T. Zhang  Z. Li 《Journal of fish biology》2000,57(4):867-880
Feeding ecology of three small fish species, Hypseleotris swinhonis, Ctenogobius giurinus and Pseudorasbora parva was studied seasonally in the Biandantang Lake, a small, shallow lake in central China. Gut length, adjusted for total body length, was significantly higher in spring than in other seasons for all the three species. Seasonal changes in gut length were not associated with changes in food quality. Weight of fore-gut contents, adjusted for body weight, was significantly higher in winter and spring than in summer and autumn in H. swinhonis and C. giurinus , and significantly higher in autumn than in spring and summer for P. parva. Percentage of empty fore-guts was highest in summer and lowest in spring for H. swinhonis and C. giurinus , and highest in winter and lowest in autumn for P. parva. Diet of the three small fishes showed apparent seasonal changes, and these changes reflected partly the seasonal fluctuations of food resources in environment. Diet breadth was high in winter and low in autumn for H. swinhonis , high in winter and low in spring and summer for C. giurinus , and high in autumn and low in spring for P. parva. Diet overlaps between pairs of species were biologically significant in most cases, except between H. swinhonis and P. parva in summer and autumn and between C. giurinus and P. parva in autumn.  相似文献   

16.
The dynamics of growth and the contents of free and bound endogenous IAA, gibberellins (GA), cytokinins (zeatin and its riboside), and ABA in kidney bean plants (Phaseolus vulgaris L., cv. Belozernaya) grown in darkness or in the light was studied. Phytohormones were quantified in 5–15-day-old plants by the ELISA technique. Plant growth and phytohormone content were shown to depend on plant age and the conditions of illumination. During scotomorphogenesis, changes in the biomass and hypocotyl length were highly correlated with the content of GA, whereas during photomorphogeneses, these parameters were correlated with the content of zeatin. In darkness, epicotyl growth displayed a positive correlation with the content of GA, whereas in the light, the correlation was negative. Growth characteristics of the primary leaves were shown to correlate with IAA in darkness and with GA and zeatin in the light. At a low concentration of cytokinins in illuminated leaves, cell divisions occurred, whereas, at the higher cytokinin concentrations, cell expansion occurred. The highest content of GA was characteristic of leaves in the period of growth cessation. ABA accumulated during active leaf and root elongation and biomass increment in the light and during hypocotyl growth in darkness. After plant illumination, the ratio of auxins to cytokinins increased in bean roots and decreased in their epicotyls. Thus, light changed the developmental programs of bean plants, which was manifested in the changed rate and duration of growth of various organs (root, hypocotyl, epicotyl, and leaf). Some mechanisms of light action depended on the contents of IAA, ABA, GA, and cytokinins and the ratios between these phytohormones. Differences between scotonorphogenesis of mono-and dicotyledonous plants are discussed in relation to the levels of phytohormones in them.  相似文献   

17.
啮齿动物作用下退耕地山杏种子扩散与贮藏的季节变化   总被引:2,自引:0,他引:2  
啮齿动物对植物种子的取食和扩散影响种子的时空分布,继而影响种子的萌发和幼苗建成,因而在森林更新中起着重要作用.在国有济源市愚公林场,选择退耕地生境,于春季、夏季、秋季分别释放人工标记的山杏种子,观察啮齿动物扩散与埋藏山杏种子的季节性差异.结果表明:1)退耕地中的啮齿动物主要包括大林姬鼠、社鼠、黑线姬鼠;2)山杏种子扩散速率在春季显著慢于夏季,夏季显著慢于秋季;3)种子搬运量受季节和种子状态交互作用影响,春季显著少于夏季,夏季显著少于秋季;4)不同季节种子平均搬运距离不同,秋季不同状态种子的搬运距离均大于春季和夏季;5)啮齿动物对山杏种子的贮藏点大小多为1粒种子,少量为2、3粒种子,且贮藏点大小与季节间存在显著的交互作用,春季单粒种子的贮藏点数量显著少于夏季和秋季,而夏季与秋季的贮藏点则倾向于多粒种子;6)在夏季和秋季各有5枚(共释放1800枚)被啮齿动物分散贮藏的山杏种子建成幼苗.  相似文献   

18.
The activity of tyrosinase, the rate-limiting enzyme for melanin synthesis, is higher in Black skin melanocytes than in melanocytes derived from Caucasian skin. This variation in enzyme activity is not due to differences in tyrosinase abundance or tyrosinase gene activity, but, rather, is due to differences in the catalytic activity of preexisting tyrosinase. In melanocytes, tyrosinase is localized to the membrane of melanosomes and in Caucasian melanocytes the melanosome-bound enzyme is largely inactive. Conversely, in melanosomes of Black melanocytes, tyrosinase has high catalytic activity. Treatment of Caucasian melanocytes with the lysosomotropic compound ammonium chloride or with the ionophores nigericin and monensin results in a rapid and pronounced increase in tyrosinase activity. This increase occurs without any change in tyrosinase abundance, indicating that these compounds are increasing the catalytic activity of preexisting enzyme. Inhibition of the vacuolar proton pump V-ATPase by treatment of Caucasian melanocytes with bafilomycin also increases tyrosinase activity. In contrast to the 10-fold increase in tyrosinase observed in Caucasian melanocytes, neither ammonium chloride, monensin, nigericin, nor bafilomycin is able to increase the already high level of tyrosinase activity present in melanosomes of melanocytes derived from Black skin. Finally, staining of Caucasian melanocytes with the fluorescent weak base acridine orange shows that melanosomes of Caucasian, but not Black, melanocytes are acidic organelles. These data support a model for racial pigmentation that is based on differences in melanosome pH in Black and Caucasian skin types. The models suggests that melanosomes of Caucasian melanocytes are acidic, while those of Black individuals are more neutral. Since tyrosinase is inactive in an acid environment, the enzyme is largely inactive in Caucasian melanosomes but fully active in Black melanosomes.  相似文献   

19.
1849年,捷克人Presl根据菲律宾产的一种蕨类植物Anisocampium cumingia-num Presl,建立了安蕨属Anisocapium Presl,几十年来未被各国植物学家(如Baker、Beddom、Makino、C.Christensen、Christ、Nakai、秦仁昌、Devol、Ohwi和Tagawa)所承认。1940年,Tard.-Blot et C.Chr.编写《印度支那植物通志》(Fl.Gen.Indo-Chine)时接受了安蕨属的概念。1947年,美国人Copeland研究东南亚蕨类植物时,也肯定了安蕨属是一个自然分类群。以后,  相似文献   

20.
We investigated the effects of whole-plant nutrient-availability on the degree of distribution of some plant primary and secondary (nitrogen, fibre, flavonols, gallotannins and cineole) chemicals across young, mature and old leaves of seedlings of Eucalyptus nitens. Four treatments that ranged from low to high nutrient-application rates resulted in mean whole-plant foliar concentrations of 0.63%, 0.85%, 1.11% and 1.82% nitrogen dry matter (N%DM) for treatments A, B, C and D, respectively. Within-plant distribution (across the leaf age profile of young, mature and old leaves within a eucalypt seedling) of N%DM ranged from zero in treatment A to a wide range of distribution in treatment D (low N%DM concentrations in old leaves to high N%DM concentrations in young leaves). Similarly, the distribution of fibre ranged from zero in treatment A to a wide range of distribution in treatment D, but with high concentrations in old leaves and low concentrations in young leaves. In contrast, flavonols (weakly) and gallotannins had a wide range of distribution in treatment A (low concentrations in old leaves to high concentrations in young leaves) but were little or not distributed in the other treatments. Again in contrast, cineole was strongly distributed between old and young leaves (low concentrations in old leaves to high concentrations in young leaves) across all treatments while concentrations in mature leaves reflected one or other leaf age depending on treatment. Protein precipitable phenols in treatments A, B and C were high in young, and low in old leaves; whereas in treatment D they were low and similar between leaves of different ages.  相似文献   

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