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The penial and tarsal morphology of Protimesius is studied and morphological data support the revalidation of Obidosus with the subsequent new combinations (20 species) and restored combinations (two species). Emended diagnoses are proposed for both genera, and two cave-dwelling new species of Protimesius are described and illustrated: P. lucifer sp. nov. (Pará state) and P. orcus sp. nov. (Ceará state). An identification key to the species of Protimesius and distributional maps of Obidosus and Protimesius are provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:C4E9C04D-A646-41E4-AE59-B6D0C951DEAB  相似文献   

2.
Two new species of short-tailed whip-scorpions (schizomids), Calima embera sp. nov. and Calima nutabe sp. nov. are described based upon collected material from the Natural Park Planes de San Rafael, Risaralda department, and the Natural Reserve El Romeral, Antioquia department, Colombia, increasing the number of known species for the genus to four; an identification key and a distribution map for Calima species, are provided. The voluminous spermathecal lobes in females and the presence of a small dorsal eminence basal to Dm4 in the male flagellum of some species, could represent diagnostic characters for Calima and are therefore included in its diagnosis. The microsetae of the male flagellum of Hubbardiinae, continues be excluded from the setal homologies; we suggest that they must be taken into consideration in a future homology proposal. www.zoobank.org/urn:lsid:zoobank.org:pub:1D3A97A4-29A6-46E2-AD78-EE6C7036D251  相似文献   
3.
Pseudonemesia tabiskey sp. nov. is described from an Andean Forest in Trujillo, Venezuela. The new species is the third for the genus and differs from the other two species by the presence of one short and apically rounded modified seta on the retrolateral distal portion of the male tibia I and clavate setae on the dorsal and lateral sides of abdomen in both sexes. A new diagnosis is given to Pseudonemesia and new morphological data based on scanning electron microscopy for the Microstigmatinae are presented. The presence of posterior median spinnerets in Pseudonemesia is discussed.  相似文献   
4.
近红外光谱技术已经有效应用于表征原材料和经过后整理的纺织产品.基于相对简单的近红外光易识别的化学基团(如:C—H,O—H和N—H),该技术已发展成为聚合物产品最重要的表征方法之一.通过近红外光谱分析定量化表征历史纺织品“Curtain Dress”中的棉纤维素纤维降解程度,研究同一棉纺织产品中引起诸如颜色等不同外观变化的纤维结构形态和大分子结构变化机理.利用Brimrose Luminar 5030近红外分析仪测试获得了“Curtain Dress”包括上身和裙子的8处不同程度褪色区域的近红外光谱,根据近红外光谱吸收峰识别了棉纤维素纤维的典型官能团C—H、C—O和0一H等.并通过主元分析法(PCA,Principle component analysis)分析了不同褪色区域的功能基团振动变化.研究发现第一和第二主成分的因子综合得分F很好地解释了分子中各组成键原子高达99.09%的振动变化程度,有效地反映了在褪色过程中纤维结构与形态变化机理.  相似文献   
5.
Convergence across biomes to a common rain-use efficiency   总被引:7,自引:0,他引:7  
Water availability limits plant growth and production in almost all terrestrial ecosystems. However, biomes differ substantially in sensitivity of aboveground net primary production (ANPP) to between-year variation in precipitation. Average rain-use efficiency (RUE; ANPP/precipitation) also varies between biomes, supposedly because of differences in vegetation structure and/or biogeochemical constraints. Here we show that RUE decreases across biomes as mean annual precipitation increases. However, during the driest years at each site, there is convergence to a common maximum RUE (RUE(max)) that is typical of arid ecosystems. RUE(max) was also identified by experimentally altering the degree of limitation by water and other resources. Thus, in years when water is most limiting, deserts, grasslands and forests all exhibit the same rate of biomass production per unit rainfall, despite differences in physiognomy and site-level RUE. Global climate models predict increased between-year variability in precipitation, more frequent extreme drought events, and changes in temperature. Forecasts of future ecosystem behaviour should take into account this convergent feature of terrestrial biomes.  相似文献   
6.
Investigation of the human antibody response to influenza virus infection has been largely limited to serology, with relatively little analysis at the molecular level. The 1918 H1N1 influenza virus pandemic was the most severe of the modern era. Recent work has recovered the gene sequences of this unusual strain, so that the 1918 pandemic virus could be reconstituted to display its unique virulence phenotypes. However, little is known about adaptive immunity to this virus. We took advantage of the 1918 virus sequencing and the resultant production of recombinant 1918 haemagglutinin (HA) protein antigen to characterize at the clonal level neutralizing antibodies induced by natural exposure of survivors to the 1918 pandemic virus. Here we show that of the 32 individuals tested that were born in or before 1915, each showed seroreactivity with the 1918 virus, nearly 90 years after the pandemic. Seven of the eight donor samples tested had circulating B cells that secreted antibodies that bound the 1918 HA. We isolated B cells from subjects and generated five monoclonal antibodies that showed potent neutralizing activity against 1918 virus from three separate donors. These antibodies also cross-reacted with the genetically similar HA of a 1930 swine H1N1 influenza strain, but did not cross-react with HAs of more contemporary human influenza viruses. The antibody genes had an unusually high degree of somatic mutation. The antibodies bound to the 1918 HA protein with high affinity, had exceptional virus-neutralizing potency and protected mice from lethal infection. Isolation of viruses that escaped inhibition suggested that the antibodies recognize classical antigenic sites on the HA surface. Thus, these studies demonstrate that survivors of the 1918 influenza pandemic possess highly functional, virus-neutralizing antibodies to this uniquely virulent virus, and that humans can sustain circulating B memory cells to viruses for many decades after exposure-well into the tenth decade of life.  相似文献   
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