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161.
162.
ABSTRACT. Free-living amoebae belonging to the species Naegleria fowleri are known to be the etiological agents for a form of fulminant meningoencephalitis that is generally fatal (primary amoebic meningoencephalitis). In a broad bacterial screening from soil and water we have isolated three strains (M-4, D-13 and A-12) belonging to the species Bacillus licheniformis that have remarkable amoebicidal activity against Naegleria sp. and also against different Gram-positive and Gram-negative bacteria. Physical-chemical characteristics, partial purification and biological activities of a substance produced by the M-4 strain have been investigated. This substance (m-4) is stable at high temperature (up to 100°C) and extremes of pH (2.5-9.5) and also at -20°C for months. Its production is greatly influenced by oxygenation of the cultures and is probably related to the sporulation process of the bacterium. Scanning electron microscope observations reveal that amoebae are lysed after a few minutes contact with m-4.  相似文献   
163.
Twenty‐three isolates of the widely distributed marine bacteria Alteromonas macleodii have been analysed by multilocus sequence analysis combined with phylogenetic and multivariate statistical analyses. The strains originated from the Pacific Ocean, Mediterranean Sea, English Channel, Black Sea and Thailand. Using the nucleotide sequences of nine loci for each of the 23 isolates, a robust identification was achieved of different clades within the single species. Strains generally clustered with the depth in the water column from which the isolate originated. Strains also showed more recombination with isolates from the same vicinity, suggesting that genetic exchange plays a role in diversification of planktonic marine prokaryotes. This study thus shows for the first time for a large set of isolates of a species of planktonic marine prokaryotes that multilocus sequence analysis overcomes the problems associated with the analysis of individual marker genes or presence of extensive recombination events. It can thus achieve intraspecific identification to the level of genotypes and, by comparison with relevant environmental data, ecotypes.  相似文献   
164.
Abstract A new classification of Sitonini Gistel into ten genera is proposed, derived from a phylogenetic analysis based on morphology. Two subgenera of Sitona, Charagmus and Coelositona, are promoted to genus level. Sitona is restricted to the former nominotypical subgenus and redefined using apomorphies, and several species previously included in it are transferred to the genus Coelositona González. The species composition of the genus Charagmus Schönherr is unchanged. Andrion gen.n. is described (type species: Curculio regensteinensis Herbst, 1794). Catachaenus Schönherr, 1840 is synonymized with Eugnathus Schönherr, 1834 ( syn.n. ). Homalorhinus lutosus Hochhuth, 1847 is removed from Sitonini. The relationships represented by the new classification correspond with the evolution of Fabaceae (Leguminosae), mostly with the group of ‘temperate herbaceous tribes’ or Hologalegina. This group is divided into the sister clades, Loteae s.l. and IRLC (inverted repeat‐lacking clade) – a clade well defined by the loss of a structural mutation in the genome of the chloroplast. Andrion does not feed on Hologalegina. Charagmus and Coelositona feed on species of Loteae s.l., whereas members of the genus Sitona feed on species in IRLC. This ability to feed on IRLC plants seems to have been a key trait that enabled the radiation of Sitona into more than 100 species. A key to the genera of Sitonini and illustrations of important morphological features are provided. A new structure is described from the internal sac, the ‘hamuli’. The variability of hamuli between the species of Sitonini is an important new tool in the taxonomy of this tribe. New combinations: Eugnathus circulus (Eydoux & Souleyet, 1839), E. mangarinicus ( Voss, 1925 ), E. scintillans (Pascoe, 1874), E. sulcifrons ( Heller, 1934 ), Charagmus gressorius (Fabricius, 1792), Ch. intermedius Küster, 1847, Ch. griseus (Fabricius, 1775), Ch. cachectus Gyllenhal, 1834, Ch. stierlini Reitter, 1903 , Ch. variegatus (Fåhraeus, 1840), Coelositona ribesi ( González, 1971 ), C. cambricus (Stephens, 1831), C. cinerascens (Fåhraeus, 1840), C. limosus (Rossi, 1792), C. ocellatus (Küster, 1849), C. latipennis (Gyllenhal, 1834), C. puberulus ( Reitter, 1903 ), C. villosus (Allard, 1869), Andrion regensteinense (Herbst, 1794) and Anemeroides lutosus (Hochhuth, 1847).  相似文献   
165.
Orobanche icterica Pau, frequently regarded as a synonym for O. elatior Sutton, is lectotypified on Pau's original material from the herbarium of the Real Jardín Botánico in Madrid (MA 115079!). Its morphology is described with special emphasis on those characters which distinguish it from O. elatior. O. icterica is mainly found in the east of the Iberian Peninsula and sporadically in the south and north-west. It is considered to be close to O. elatior but deserving recognition at specific level.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 117–124.  相似文献   
166.
Deep misunderstandings still besiege taxonomy after more than 200 years of fruitful output. It has been asserted in this journal that taxonomy should be integrative and conform to a series of restrictive guidelines. We show that taxonomy has been integrative for most of its history although, in our sense, integrative does not mean the indiscriminate pooling of any source of data. The guidelines proposed are not founded in good scientific rationale and can have, if followed, a detrimental effect not only on taxonomy, but also on biology as a whole.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 211–216.  相似文献   
167.
Numerical taxonomy study of Salvia sect. Salvia (Labiatae)   总被引:1,自引:0,他引:1  
Multivariate analysis was carried out in order to elucidate the taxonomic relationships between Salvia officinalis L., the type species of the genus, and S. fruticosa Mill., both taxa included in section Salvia (Labiatae). Seventy-five different herbarium specimens from all over the Mediterranean Region, belonging to these two taxa, were analysed. Twenty-four specimens belonging to S. lavandulifolia Vahl. s.l. , were used as outgroups. Twenty-six morphological characters were measured and a data matrix was constructed prior to multivariate analysis by means of R software. Multiple correspondence analysis was used to obtain a single dendrogram, applying Ward's minimum variance algorithm. This tree was used as a basis to propose a key for the determination of the species and subspecies studied. S. lavandulifolia is separated in two groups, one belonging to S. officinalis and another one representing what was called S. blancoana . Salvia officinalis L. ssp. gallica (W. Lippert) Reales, D. Rivera & Obón and S. officinalis L. ssp. oxyodon (Webb & Heldr.) Reales, D. Rivera & Obón are discussed as new combinations. In addition, a hybrid between S. officinalis and S. fruticosa is identified and its importance in gardening and cultivation is discussed. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 353–371.  相似文献   
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169.
Abstract This study investigates how abundance, diversity and composition of understorey spiders were influenced by four different forest habitats in a southern Brazilian Araucaria forest. The study area encompasses a landscape mosaic comprised of Araucaria forest, Araucaria plantation, Pinus plantation, and Eucalyptus plantation. Understorey spiders were collected by beating the vegetation inside three patches of each forest habitat. To assess possible predictors of spider assemblage structure, several patch features were analysed: potential prey abundances, estimation of vegetation cover, diversity index of vegetation types, patch ages, patch areas, and geographical distance between patches. To assess the influence of high‐level taxa approaches on spider assemblage patterns, analyses were carried out individually for family, genera and species levels. Additionally, Mantel tests were carried out in underlying similarity matrices between each taxon. Significant differences in spider abundances among forest habitats were found. Pinus plantations showed the highest abundance of spiders and Eucalyptus plantations showed the lowest abundance. Spider abundance was significantly influenced by patch ages, geographical distance and vegetation cover. Expected numbers of families, genera and species did not vary among forest habitats. Spider composition of two Eucalyptus patches differed from the other forest patches, probably due to their low vegetation cover and isolation. Genera composition was the best correlate of species composition, showing that a higher‐level surrogate can be an alternative to the species approach. The understorey spider diversity in this managed area could be maintained when suitable habitat structures are provided, thus ensuring the connectivity between different habitat types. Further studies should focus on individual species responses to the conversion of native forest to monocultures.  相似文献   
170.
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