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1.
对长春和北京地区连续12年(1976年冬至1988年春)引起小儿肺炎的3、7型腺病毒102株标本,进行了限制性内切酶核酸电泳图谱分析。56株7型腺病毒经BamHⅠ、BclⅠ、BglⅠ、XbaⅠ、SmaⅠ、HindⅢ分析后,表现为两个基因组型——Ad7 b和Ad7 d。46株3型腺病毒被Bg1 Ⅱ、BamHⅠ酶解后,表现为 3个基因组型——Ad 3Ⅰ、Ad 3Ⅱ、Ad 3Ⅲ。各基因组型的分布情况是:56株7型腺病毒中,43株为Ad 7 b(76.8%),流行于1976年冬至1986年春;13株是Ad 7 d(23.2%),出现于1982年,与Ad 7 b共同流行;1986年~1988年分析的5株病毒都是Ad 7d。43株3型腺病毒中,Ad3Ⅰ42株(91.0%),分布于12年中;Ad 3Ⅱ、Ad 3Ⅲ各2株,散在分布。此结果表明,国内这12年中引起小儿肺炎的3型腺病毒至少有3个基因组型,7型腺病毒至少有两个基因组型。Ad3Ⅰ和Ad7 b是流行优势基因组型。但自80年代初开始出现Ad7 d以来,有逐年增多的趋势,最近两年的标本又都是Ad7 d,很可能它将取代Ad7 b而成为流行的优势基因组型.  相似文献   

2.
为开展紫芝的杂交育种,对6个紫芝菌株的不亲和性因子进行分析。通过原生质体单核化,6个紫芝获得9个不同亲本型的单核化菌株,共测得7个不同的A因子和7个不同的B因子,A、B因子的多态性各占单核体的77.8%,表明紫芝有较丰富的交配型因子,为紫芝的杂交育种奠定基础。  相似文献   

3.
The structure of the stomatal apparatus of the leaf of Lycopodium japonicum Thumb was studied using epidermal macerations, sections and scanning electron microscopy. The stomatal apparatus of L. japonicum consists of two large guard cells and pore, and is anomocytic. Based on light microscopy, the impression from epidermal macerations that there were two small guard cells surrounded by two, large, similarly shaped, subsidiary cells (paracytic) derives from a pronounced elliptical cuticular ledge on the surface of the guard cells surrounding a thickened circumporal area. A similar appearance is characteristic of cuticle preparations of the Devonian lycophyte Drepanophycus spinaeformis Göppert. We therefore conclude, as did W.H. Lang over 70 years ago, that the stomata of the early lycophyte were also anomocytic, as were those of a second species of Drepanophycus , D. qujingensis Li & Edwards.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 209–216.  相似文献   

4.
福建武夷山的锈菌   总被引:1,自引:0,他引:1  
福建武夷山锈菌区系基本上属于温带性质,温带型的种占60%以上,也有不少亚热带和热带型的种,本地区是温带和热带锈菌的交汇处。区系成分以东亚成分占显著地位,约占总种数的38.7%;中国特有种有14种,占9.3%;世界广布种占14%;尚有广布整个北半球的泛北极种类,分布欧亚大陆的种类以及亚洲和美洲间断分布的种类。本地区锈菌在种属组成上与日本和我国台湾省相近,已知种中分别有74%和60%以上与日本和我国台湾的种相同,说明它们同属一个区系。寄生在蕨类上被称作“活化石”的原始类型如拟夏孢锈(Uredinopsis)和明痂锈(Hyalopsora)在武夷山各采到了若干种,据此推测第四纪冰期武夷山地区可能也是古老生物的天然避难所之一。  相似文献   

5.
不同种类农药表面活性剂对大型溞的急性毒性   总被引:2,自引:0,他引:2  
运用评价化学品对水生生物毒性的标准试验方法,比较了39种非离子型、6种阴离子型和3种阳离子型的常用代表性表面活性剂对大型溞的急性毒性.结果表明:3种阳离子型表面活性剂1427、1227及C8-10的急性毒性均为剧毒,其中1427毒性最高,EC50值为0.97×10-2 mg·L-1;非离子型表面活性剂中蓖麻油聚氧乙烯醚、吐温和斯潘系列乳化剂均为低毒,而烷基酚聚氧乙烯醚系列和脂肪醇聚氧乙烯醚系列表面活性剂的毒性稍偏高,而AEO-7和AEO-5的毒性达到高毒水平,EC50值分别为0.82和0.97 mg·L-1,且此类表面活性剂脂溶性越大,对大型溞的毒性越大;大部分阴离子表面活性剂的毒性为中毒,但NNO表现为高毒,EC50值为0.17 mg·L-1.  相似文献   

6.
The Xinjiang region with residents from more than 13 minorities represents an area of many diverse ethnicities. This ethnic diversity in relation to their blood groups and immune status may have a consequential impact on the clinical status of married couples. To evaluate the risks of haemolytic disease in new-born infants, we investigated the rate of blood-group incompatibility among 487 married couples from four ethnic minorities, namely the Han, Hui, Uyghur and Kazak populations. Han minority married couples showed significantly different ABO, Rh and K phenotype frequencies between marrial relationship, whereas there was no significant difference in ABO, Rh and K phenotypes between the Uyghur, Hui and Kazak .There was a significant difference between ABO blood types in Han married couples, in the Kazak Rh-C phenotype and in the Uyghur Rh-D phenotype. The Hui married couples only demonstrated ABO, Rh and K phenotypes. The Hui minority showed the highest incompatibility rate for Rh-C and Rh-E phenotypes between mothers and their new-born infants. The highest incompatibility rate for the ABO phenotype occurred in the Kazak group. These results particularly demonstrate the clinical issues relating to ABO and Rh incompatibility, in the Kazak and Hui minorities, respectively.  相似文献   

7.
Abstract. Globally applicable sets of terrestrial plant functional types (PFTs) have been identified as a major need in the development of dynamic global vegetation models for use with global atmospheric models. Global sets of PFTs should represent the world's most important plant types; characterize them through their functional behavior; and provide complete, geographically representative coverage of the world's land areas. Three main schools of thought on PFTs have emerged: (1) a physiological focus on internal function, especially at the level of basic metabolism; (2) an ecological focus on function in relation to plant form and environmental conditions; and (3) a geophysical focus on how plant functions affect the adjacent atmosphere. A structural approach based on pheno-physiognomy permits ready identification of relatively familiar, recognizable plant types. Many of the criteria cited by other approaches also are intimately related to structure and its seasonal changes. An earlier global system of structural-functional PFTs and their climatic relations has been improved, including addition of less well-known plant types, and is briefly described. A more strictly ‘functional’ approach is proposed, in which major aspects of plant function, initially metabolism and water balance, are used to classify functional types and suggest how these are constrained by climate. Such functional considerations, however, are closely linked to structural manifestations - but also require other functional criteria for more completely functional classifications. A recent global model of potential natural vegetation types suggested ca. 15 major plant types as necessary to cover the world's main terrestrial vegetation patterns. These essential types correspond well with a first-cut set of structural types implied by metabolic considerations.  相似文献   

8.
9.
四川浓香型与酱香型酒曲细菌区系构成的比较研究   总被引:5,自引:0,他引:5  
李佑红  吴衍庸   《微生物学通报》1992,19(4):211-214
浓香型酒和酱香型酒,不仅发酵制酒的工艺各异,而且制曲工艺也不同。由于制曲工艺的不同,因而影响到两大类酒曲中微生物区系的组成。本文报道将酒曲中的细菌分为三大类群:产酸细菌;底物分解细菌;放线菌,并进行了计数,研究了它们数量组成与结构特征。讨论了这些细菌与两大类型酒风格形成的关系。  相似文献   

10.
Fibroblast growth factor receptor 3 (FGFR3) signaling pathways are essential for normal longitudinal bone growth. Mutations in this receptor lead to various human growth disorders, including Achondroplasia, disproportionately short-limbed dwarfism, characterized by narrowing of the hypertrophic region of the epiphyseal growth plates. Here we find that FGF9, a preferred ligand for FGFR3 rapidly induces the upregulation and secretion of the matrix resident phosphoprotein, osteopontin (OPN) in cultured chicken chondrocytes. This effect was observed as early as two hours post stimulation and at FGF9 concentrations as low as 1.25 ng/ml at both mRNA and protein levels. OPN expression is known to be associated with chondrocyte and osteoblast differentiation and osteoclast activation. Unexpectedly, FGF9 induced OPN was accompanied by inhibition of differentiation and increased proliferation of the treated chondrocytes. Moreover, FGF9 stimulated OPN expression irrespective of the differentiation stage of the cells or culture conditions. In situ hybridization analysis of epiphyseal growth plates from chicken or mice homozygous for the Achondroplasia, G369C/mFGFR3 mutation demonstrated co-localization of OPN expression and osteoclast activity, as evidenced by tartarate resistant acid phosphatase positive cells in the osteochondral junction. We propose that FGF signaling directly activates OPN expression independent of chondrocytes differentiation. This may enhance the recruitment and activation of osteoclasts, and increase in cartilage resorption and remodeling in the chondro-osseus border.  相似文献   

11.
目的:探讨不同类型剖宫产瘢痕妊娠(CSP)的治疗方法。方法:选择经临床确诊为CSP的患者60例,根据CSP的类型分为内生型组(Ⅰ组)19例和外生型组(Ⅱ组)41例,每组再根据不同治疗方法各分为两个亚组,Ⅰ组包括:ⅠA组应用甲氨喋呤(MTX,Methotrexate)后超声引导下清宫术(7例);ⅠB组应用MTX及双侧子宫动脉灌注化疗栓塞术(UACE,Uterine aytery embolization chemotherapy)后超声引导下清宫术(12例)。Ⅱ组包括:ⅡA组行超声引导下清宫术+/-MTX(11例);ⅡB组应用MTX+UACE+超声引导下清宫术(30例)。以妊囊大小、术中出血量、人绒毛膜促性腺激素(β-human chorionic gonadotropin,β-HCG)恢复正常时间、首次治愈率、二次治愈率、住院时间、住院费用及月经恢复正常时间、术后妊娠率作为疗效评估参数比较两组中亚组间相关数据的差异。结果:Ⅰ组中,两亚组妊囊大小、术中出血量、住院天数、血HCG及月经恢复时间、首次治愈率比较差异无统计学意义(P0.05);ⅠA组住院花费明显少于ⅠB组(P0.05)。Ⅱ组中,两亚组住院天数、住院费用及妊囊大小比较差异无统计学意义(P0.05);ⅡA组术中出血量及月经恢复时间明显多于ⅡB组,血HCG下降率及首次治愈率明显低于ⅡB组(P0.05)。结论:CSP可根据类型选用合适的治疗方法。内生型适用于MTX+超声引导下清宫术,而外生型适用于MTX+UACE+超声引导下清宫术。  相似文献   

12.
五味子属雄花的形态发生及其系统学意义   总被引:5,自引:0,他引:5  
  相似文献   

13.
We have previously reported the phenotypic characterization of methicillin-resistant Staphylococcus aureus (MRSA) clinical strains isolated in Malaya University Hospital in the period 1987 to 1989 using antibiogram, coagulase typing, plasmid profiles, and phage typing. Here, we report the analysis of the same strains with three genotyping methods; ribotyping, pulsed-field gel electrophoresis (PFGE) typing, and IS431 typing (a restriction enzyme fragment length polymorphism analysis using an IS431 probe). Ribotyping could discriminate 46 clinical MRSA strains into 5 ribotypes, PFGE typing into 22 types, and IS431 typing into 15 types. Since the differences of the three genotyping patterns from strain to strain were quite independent from one another, the combined use of the three genotyping methods could discriminate 46 strains into 39 genotypes. Thus, the powerful discriminatory ability of the combination was demonstrated.  相似文献   

14.
In previous studies, neuronal cell bodies, excised by hand from bovine spinal ganglia, were analyzed and heterogeneous intermediate and high molecular weight neurofilament proteins that differed in electrophoretic mobility from their axonal counterparts were demonstrated (1, 2). In the present experiment, intermediate and high molecular weight neurofilament proteins of the axonal type were treated with alkaline phosphatase, and neurofilament proteins enriched in perikaryal type proteins were labeled with32P. Results showed that neurofilament proteins were phosphorylated after their translation, in the perikarya and the proximal portion of the axon, and suggested that phosphorylation was responsible for the differences between axonal and perikaryal neurofilament proteins.Special Issue dedicated to Prof. Holger Hydén.  相似文献   

15.
Swine-specific sequence tagged (microsatellite) sites, STS and STMS, were assigned chromosomally by polymerase chain reaction analysis of a somatic cell hybrid panel. This study confirms the localization from genetic mapping of seven anonymous microsatellites and the genes ANPEP, ATP2, CGA, DAGK, FSHB, IFNG, IGF1, IL1B and SPP1. New assignment for the gene BNP1 to chromosome 6 is reported. The confirmed and the new assignments extend the information of the previously established linkage maps and provide framework loci on which to order additional informative markers.  相似文献   

16.
The great morphological variation in staminate flowers makes it favorable for its use as the main criteria for infrageneric classification in the genus Schisandra (Schizandra) Michx. Organogenesis of different kinds of the staminate flowers has been observed under SEM. Combined with other currently available studies, the patterns of morphogenesis of the staminate flowers are categorized into three types: the columnar-torus type, the flattened-torus type, and the spherical-torus type. In the columnar-torus type, the torus of the staminate flower is kept columelliform through out the whole ontogenic process of the flower; this type can be further divided into two subtypes—the sphenantheraceous subtype, with the thecae laterally localized on both sides of the connective of the mature stamen, and the grandifloraceous subtype, instead with the thecae located outward or slightly outward. In the flattened-torus type, the torus of the staminate flower gradually becomes swollen and then flattened in the process of floral development, and forms a pentagonal shield together with the enlarged filaments and connectives of the stamen. The torus of the staminate flower in the spherical-torus type becomes carnified and swollen with the stamen growing into the depressions or cavities of the spherical torus. Among the three types, the columnar-torus one might be the primitive type, from which the other two were derived representing two different evolutionary trends respectively. By analyzing the cause of the morphological variation of the staminate flowers, it is suggested that the evolutionary pressure by the insect eating during pollinating enhanced the drastic differentiation of the morphology of the staminate flowers. In some taxa of the genus, in which the Coleoptera acted as the main pollinating agent, the enlargement of the torus of the staminate flower to form a thick flattened shield or a spheroid might be an adaptive fitness to the phylogenetic decreasing in number of the stamen. The primitiveness in stamen morphology of the Schisandra staminate flowers is also discussed, which might agree with the origin antiquity of the genus. The similarity of its heteropolar 3- or 6-aperturate pollen to the 3-aperturate pollen of Eudicots might result from convergent evolution. In addition, main infrageneric classifications of Schisandra and the systematic p  相似文献   

17.
Rhizobia are Gram-negative bacteria than can elicit the formation of specialized organs, called root nodules, on leguminous host plants. Upon infection of the nodules, they differentiate into nitrogen-fixing bacteroids. An elaborate signal exchange precedes the symbiotic interaction. In general, both rhizobia and host plants exhibit narrow specificity. Rhizobial factors contributing to this specificity include Nod factors and surface polysaccharides. It is becoming increasingly clear that protein secretion is important in determining the outcome of the interaction as well. This paper discusses our current understanding of the symbiotic role played by rhizobial secreted proteins, transported both by secretion systems that are of general use, such as the type I secretion system, and by specialized, host-targeting secretion systems, such as the type III, type IV and type VI secretion systems.  相似文献   

18.
O6-Substituted guanine and hypoxanthine derivatives were prepared and tested for their cytokinin activity by the tobacco callus, radish cotyledons and lettuce seed bioassay systems. The results indicated that some derivatives of both types possess cytokinin activity.  相似文献   

19.
生物多样性的熵值结构   总被引:3,自引:0,他引:3  
欧乐其  何小双 《植物研究》1996,16(1):146-154
多样性一般定义为生物进化过程中物种表现型的丰富程度。从广义上讲,生物进化与环境归类作用的结构复杂性对生物为多样性的解释是很有益处的。我们认为区域水平与样地水平上的气候归类型与植被归类型是最基本的划分因子,本文以中国东北部黑龙江省的山地植被为例,采用多等级熵值分配的方法来证明所使用的方法。我们得出气候归类型与植被归类型所占有的熵值成分要弱于物种表现型丰富度所占有的熵值成份。值得注意的是其相对的熵值贡献率对每一个因子的最大熵值的变化规律。分析结果表明气候归类型占有较低的熵值而植被归类型占有较高的熵值。因此仅仅以在区域气候型为主要指标所划分的物种生态位是不够的,而以小区域内的植被型为指标所产生的物种生态位具有较高利用价值。  相似文献   

20.
Two rod-like opsin genes, conf and cond , were isolated from the common Japanese conger Conger myriaster . The predicted proteins of conf and cond consisted of 354 and 350 amino acid (aa) residues respectively, and the aa identity was 87.4%. Phylogenetic analysis suggested that conf and cond are homologous to the freshwater type and the deep-sea type rod opsin genes of freshwater eels. RT-PCR analyses revealed that in both juveniles and adults cond is expressed in the retina and pineal complex, while conf is only expressed in the pineal complex at a low level.  相似文献   

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