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Bill Arnold is a great scientist in whose laboratory I was privileged to work during the years he discovered the thermoluminescence and the electroluminescence of green plants. I reminisce about Bill's influences on me, scientific and otherwise, during those years.  相似文献   

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中心体蛋白Cenexin是成熟中心粒的唯一标志分子。为阐明中心粒在大鼠精子发生过程中的成熟以及功能,我们首先通过RT-PCR技术从大鼠睾丸组织中扩增出了Cenexin cDNA片段,原核表达重组蛋白后,用其免疫小鼠制备了高滴度的抗Cenexin的多克隆抗体,然后利用免疫荧光染色、Western Blot和半定量RT-PCR方法,研究了大鼠精子发生过程中Cenexin蛋白和基因的表达特征。结果显示Cenexin mRNA水平在精原细胞和精母细胞中较高,随后表达水平下降,而蛋白质分子在精原细胞到精子细胞中都定位于细胞的一个中心粒上,表示有成熟中心粒的存在,在长形精子细胞中该蛋白位于鞭毛的基体部。附睾的绝大多数成熟精子中Cenexin免疫染色消失。中心体蛋白Cenexin在精子变态期的表达变化可能与精子鞭毛形成的起始有关。  相似文献   

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灌木状竹,有时附生于树干基部。地下茎短颈粗型。秆单丛;节问圆筒形;每节分枝单一,与主秆近等粗。秆释宿存性,革质;滓耳大,镰刀状;滓舌较低;算片外展。叶耳镰刀状;  相似文献   

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1985—1986年,从福建漳州,浙江杭州,上海,江苏南京,苏州,扬州,常州等地采集100多种植物进行分离,在雪松(Cedrus deodara),倒挂仙人鞭(Cereus flagelliformis),冬青卫茅(Euonymus japonieus),构树(Broussonetia papyrifera),蓖麻(Ricinus communis),柑桔(Citrus reticulata),带叶兜兰(Paphiopedilum hirsutissimum),芋(Colocasia esculenta),鳄梨(Persea americana),山茶(Camellia sp.),珊瑚樱(Solanum pseudo-capsicum),百合(Lilium brownii var.viridulum),蔓常春花(Vinca major),西瓜(Citrullus lanatus)等14种寄主植物上分离到51个疫霉菌株,鉴定为9个种:烟草疫霉(=寄生疫霉)Phytophthora nicotianae B.de Haan(=P.parasitica Dast.),掘氏疫霉P.drechsleri Tucker,樟疫霉 P.ciunamomi Rands,棕榈疫霉P.palmivora(Butl.)Butl.,柑桔褐腐疫霉P.citrophthora(R.et E.Smith) Leon.,苎麻疫霉P.bochmeriae Saw.,蜜色疫霉P.meadii McRae,簇囊疫霉P.botryosa Chee,隐地疫霉P.cryptogea Pethyb.et Laff.。其中,烟草疫霉,掘氏疫霉,樟疫霉出现频率较高,分布较广,初步认为是上述地区植物疫病的主要病原菌。簇囊疫霉、蜜色疫霉是国内新记录。  相似文献   

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河北曲阳灵山下石盒子组植物群   总被引:4,自引:0,他引:4  
王庆之 《古生物学报》1993,32(2):218-226
研究河北曲阳灵山地区下石盒子组植物化石约18种,分析了当时的气候环境特点及变迁.并对主要植物化石进行属种描述和讨论,建立了1新属新种.  相似文献   

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Three new cytotoxic diterpenoids reniformin A, B and C, have been isolated from the leaves of Rabdosia latifolia var. reniformis Z. W. Xue et X. W. Wang. Their structures were established as (1), (2), and (3) by spectroscopic and chemical data respectively.  相似文献   

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对中国云南百合科一新种———粗穗球子草Peliosanthes pachystachya W.H.Chen&Y.M.Shui进行了描述和绘图。该新种的匍匐茎具长约18cm的节间,与匍匐球子草P.sinica Wang&Tang接近,但因叶具9-13条叶脉,花梗长9-10mm,无小苞片,花被片卵状三角形而明显不同。该新种因花被片卵状三角形,苞片披针形,也近似于长苞球子草P.ophiopogonoides Wang&Tang,但匍匐茎长,叶具9-13条叶脉,花梗长9-10mm,花葶和花序均较短而不同。  相似文献   

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When contingency tables of data on sequences, social relationships, feeding, habitat use, or other behaviour exhibit significant associations between variables, ethologists may analyse the residuals in the table in order to test more precise hypotheses about the associations found. This paper critically evaluates currently used and potentially available statistical methods for performing such tests. Specific examples of use are given and recommendations made.  相似文献   

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海南崖县中寒武统Marocella化石的发现   总被引:8,自引:1,他引:7  
林天瑞 《古生物学报》1999,38(1):102-105
Marocella hainanensis sp.nov发现于海南岛崖县大茅群,是我国中寒武世地层中首次发现,伴生的Xystriduridae科的三叶虫许多属种是组成中国,澳大利亚和南极洲中寒武世早期动物群的重要成员。  相似文献   

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The investigation of six Zinnia species afforded in addition to already known compounds two eudesmanolides, five guaianolides, three germacranolides, five elemanolides and a dihydroxygeranylgeraniol. The structures were elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic situation is discussed briefly.  相似文献   

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描述了四川无心菜属(石竹科)一新种——道孚无心菜Arenaria dawuensis A. J. Li&Q. Ban。该种具纺锤形根,聚伞花序,花柱2,线形而与纟遂瓣无心菜A. fimbriata(E. Pritz. )Mattf. 相近,但叶匙形,萼片边缘具长缘毛,花瓣短于萼片,顶端细流苏状而不同。  相似文献   

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泛素/蛋白酶体系统(UPP)是真核细胞内蛋白质选择性降解的主要途径,而蛋白酶体是UPP中蛋白质降解的场所。本文应用细胞学、统计学方法以及FTIR技术研究了蛋白酶体抑制剂MG132对青扦(Pecea wilsonii)花粉萌发、花粉管生长的影响。结果表明:MG132显著抑制青扦花粉萌发和花粉管生长,并导致花粉管形态异常,主要表现为花粉管亚顶端出现液泡化,并且液泡随着培养时间的延长而扩大到整个花粉管,花粉管濒临死亡;而DMSO以及非蛋白酶体抑制剂E-64不产生类似结果;半薄切片结果表明,MG132处理后不仅花粉管细胞质发生液泡化,生殖细胞也发生液泡化;FTIR分析进一步表明,MG132处理后,花粉管顶端的细胞壁蛋白和果胶质含量大幅度下降。上述结果表明:MG132通过抑制蛋白酶体活性显著影响青扦花粉萌发及花粉管生长;UPP在青扦花粉萌发、花粉管极性生长模式的建立和维持过程中起重要作用;抑制蛋白酶体活性将导致青扦花粉管的程序性死亡。  相似文献   

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This paper describes an automated cation-exchange chromatographic method for the simultaneous analysis of di- and polyamines, histamine, and its metabolite 1-methylhistamine. Recommendations for the selection of an effective system are made after evaluating sodium- and potassium-containing buffers, pH, temperature, column packings, and detection methods. The method can be used to analyze di- and polyamines in biological fluids, such as urine and tissue extracts, and may be useful for monitoring the effectiveness of cancer chemotherapy.  相似文献   

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本文报道了新疆子囊菌小圆孔壳属(Amphisphaerella),锥毛壳属(Coniochaeta)和座坚壳属(Rosellinia)的7个种及1个变种,即:忍冬小圆孔壳(A.xylostei),梭梭锥毛壳(C.haloxylonis),木生锥毛壳(C.ligniaria),粉被锥毛壳(C.pulveracea),毛锥毛壳(C.sordaria),附孢座坚壳(R.aquila),乳头座坚壳(R.thelena)及尖孢座坚壳大孢变种(R.apiculata var.macrospora)。其中,梭梭锥毛壳为新组合种。忍冬小圆孔壳,木生锥毛壳,乳头座坚壳及尖孢座坚壳大孢变种为我国新记录(属)种。这3个属的真菌新疆过去均未报道过,为新疆新记录属。  相似文献   

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The flies of the genus Dicranosepsis from Vietnam were investigated and classified taxonomically. Six new species (D. longa sp. nov., D. kurahashii sp. nov., D. monoseta sp. nov., D. sinuosa sp. nov., D. barbata sp. nov., and D. vietnamensis sp. nov.) are described and illustrated. Dicranosepsis is redefined and a revised key to the species is also provided.  相似文献   

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