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121.
122.
IONIC RELATIONSHIPS OF ENTEROMORPHA INTESTINALIS 总被引:4,自引:3,他引:1
123.
Julie A Pattemore James K Hane Angela H Williams Bree AL Wilson Ben J Stodart Gavin J Ash 《BMC genomics》2014,15(1)
Background
Metarhizium anisopliae is an important fungal biocontrol agent of insect pests of agricultural crops. Genomics can aid the successful commercialization of biopesticides by identification of key genes differentiating closely related species, selection of virulent microbial isolates which are amenable to industrial scale production and formulation and through the reduction of phenotypic variability. The genome of Metarhizium isolate ARSEF23 was recently published as a model for M. anisopliae, however phylogenetic analysis has since re-classified this isolate as M. robertsii. We present a new annotated genome sequence of M. anisopliae (isolate Ma69) and whole genome comparison to M. robertsii (ARSEF23) and M. acridum (CQMa 102).Results
Whole genome analysis of M. anisopliae indicates significant macrosynteny with M. robertsii but with some large genomic inversions. In comparison to M. acridum, the genome of M. anisopliae shares lower sequence homology. While alignments overall are co-linear, the genome of M. acridum is not contiguous enough to conclusively observe macrosynteny. Mating type gene analysis revealed both MAT1-1 and MAT1-2 genes present in M. anisopliae suggesting putative homothallism, despite having no known teleomorph, in contrast with the putatively heterothallic M. acridum isolate CQMa 102 (MAT1-2) and M. robertsii isolate ARSEF23 (altered MAT1-1). Repetitive DNA and RIP analysis revealed M. acridum to have twice the repetitive content of the other two species and M. anisopliae to be five times more RIP affected than M. robertsii. We also present an initial bioinformatic survey of candidate pathogenicity genes in M. anisopliae.Conclusions
The annotated genome of M. anisopliae is an important resource for the identification of virulence genes specific to M. anisopliae and development of species- and strain- specific assays. New insight into the possibility of homothallism and RIP affectedness has important implications for the development of M. anisopliae as a biopesticide as it may indicate the potential for greater inherent diversity in this species than the other species. This could present opportunities to select isolates with unique combinations of pathogenicity factors, or it may point to instability in the species, a negative attribute in a biopesticide.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-660) contains supplementary material, which is available to authorized users. 相似文献124.
Katrijn Van Deun Age K Smilde Mariët J van der Werf Henk AL Kiers Iven Van Mechelen 《BMC bioinformatics》2009,10(1):246-15
Background
Data integration is currently one of the main challenges in the biomedical sciences. Often different pieces of information are gathered on the same set of entities (e.g., tissues, culture samples, biomolecules) with the different pieces stemming, for example, from different measurement techniques. This implies that more and more data appear that consist of two or more data arrays that have a shared mode. An integrative analysis of such coupled data should be based on a simultaneous analysis of all data arrays. In this respect, the family of simultaneous component methods (e.g., SUM-PCA, unrestricted PCovR, MFA, STATIS, and SCA-P) is a natural choice. Yet, different simultaneous component methods may lead to quite different results. 相似文献125.
JESSICA E. CARILLI RICHARD D. NORRIS BRYAN BLACK SHEILA M. WALSH MELANIE McFIELD 《Global Change Biology》2010,16(4):1247-1257
Coral bleaching, during which corals lose their symbiotic dinoflagellates, appears to be increasing in frequency and geographic extent, and is typically associated with abnormally high water temperatures and solar irradiance. A key question in coral reef ecology is whether local stressors reduce the coral thermal tolerance threshold, leading to increased bleaching incidence. Using tree‐ring techniques, we produced master chronologies of growth rates in the dominant reef builder, massive Montastraea faveolata corals, over the past 75–150 years from the Mesoamerican Reef. Our records indicate that the 1998 mass bleaching event was unprecedented in the past century, despite evidence that water temperatures and solar irradiance in the region were as high or higher mid‐century than in more recent decades. We tested the influence on coral extension rate from the interactive effects of human populations and thermal stress, calculated here with degree‐heating‐months (DHM). We find that when the effects of chronic local stressors, represented by human population, are taken into account, recent reductions in extension rate are better explained than when DHM is used as the sole predictor. Therefore, the occurrence of mass bleaching on the Mesoamerican reef in 1998 appears to stem from reduced thermal tolerance due to the synergistic impacts of chronic local stressors. 相似文献
126.
HONGBO PAN FENG GAO JIQIU LI XIAOFENG LIN SALEH A. AL‐FARRAJ KHALED A.S. AL‐RASHEID 《The Journal of eukaryotic microbiology》2010,57(5):421-428
ABSTRACT. The morphology, infraciliature, and small subunit (SSU) rRNA gene sequences of two new pleurostomatid ciliates, Epiphyllum shenzhenense n. sp. and Loxophyllum spirellum n. sp., isolated from a mangrove wetland near Shenzhen, South China, were investigated. Epiphyllum shenzhenense n. sp. is morphologically characterized by leaf‐shaped cell about 150 × 35 μm in vivo, usually with four contractile vacuoles, 20–29 right kineties and 10–26 left kineties, ca. four macronuclear nodules, and two types of extrusomes (i.e. short spindle‐shaped and long bar‐shaped). As a new species, L. spirellum n. sp. is distinguished from its congeners by its posterior dorsal margin twisted onto the left side, the distribution of extrusomes (evenly arranged along the oral slit, the posterior end, and clustered to 7–13 warts on dorsal margin), the subterminally positioned contractile vacuole, the number of kineties (8–10 on right side, 4–5 on left side), and its genetic distance from congeners. Phylogenetic trees based on the SSU rRNA gene sequence for both organisms were constructed, which indicate that Epiphyllum is a distinct genus and occupies a basal position in the Pleurostomatida clade; L. spirellum n. sp. falls well into the Loxophyllum clade, which has a close relationship with Litonotus and Spiroloxophyllum. 相似文献
127.
Pulmonary acariasis is a sporadic, incidental finding in colony‐raised rhesus macaques (Macaca mulatta). Prophylactic treatment in indoor‐raised and indoor‐housed macaques is not routine due to low prevalence, lack of clinical significance, and potential risk of toxicosis. This case is an unusually severe infestation of Pneumonyssus simicola in an indoor‐housed rhesus macaque, which ultimately resulted in this animal's death. 相似文献
128.
Elevated concentrations of atmospheric
CO2 protect against and compensate for
O3 damage to photosynthetic tissues of
field-grown wheat 总被引:2,自引:0,他引:2
I. F. McKEE B. J. MULHOLLAND J. CRAIGON C. R. BLACK & S. P. LONG 《The New phytologist》2000,146(3):427-435
The effects of elevated concentrations of atmospheric carbon dioxide and ozone on diurnal patterns of photosynthesis have been investigated in field-grown spring wheat ( Triticum aestivum ). Plants cultivated under realistic agronomic conditions, in open-top chambers, were exposed from emergence to harvest to reciprocal combinations of two carbon dioxide and two ozone treatments: [CO2 ] at ambient (380 μmol mol−1 , seasonal mean) or elevated (692 μmol mol−1 ) levels, [O3 ] at ambient (27 nmol mol−1 , 7 hr seasonal mean) or elevated (61 nmol mol−1 ) levels. After anthesis, diurnal measurements were made of flag-leaf gas-exchange and in vitro Rubisco activity and content. Elevated [CO2 ] resulted in an increase in photoassimilation rate and a loss of excess Rubisco activity. Elevated [O3 ] caused a loss of Rubisco and a decline in photoassimilation rate late in flag-leaf development. Elevated [CO2 ] ameliorated O3 damage. The mechanisms of amelioration included a protective stomatal restriction of O3 flux to the mesophyll, and a compensatory effect of increased substrate on photoassimilation and photosynthetic control. However, the degree of protection and compensation appeared to be affected by the natural seasonal and diurnal variations in light, temperature and water status. 相似文献
129.
MICHAEL S. JOHNSON ROBERT BLACK 《Biological journal of the Linnean Society. Linnean Society of London》2006,89(4):689-704
The littorine genus Bembicium , restricted to Australia and Lord Howe and Norfolk Islands, provides special opportunities to examine the effects of contrasting modes of development on genetic divergence over large spatial and temporal scales. Two species, Bembicium auratum and Bembicium nanum , have planktotrophic larvae, and large, overlapping geographical distributions, whereas the three direct developers, Bembicium vittatum , Bembicium melanostoma , and Bembicium flavescens , are geographical replacements. Phylogenetic analysis of genetic distances at 28 allozyme loci supported the current taxonomic treatment of the genus and monophyly of the direct developers. Both individually and as a clade, the direct developers showed substantially greater divergence than the species with planktotrophic larvae. Controlling for geographical distance and for particular sections of coastline, genetic subdivision within the direct developers was shown to be much higher than in the planktotrophs. Low levels of subdivision in B. auratum and B. nanum over distances of 4000–6800 km indicate maintenance of substantial genetic connectivity, independent of habitat and biogeographical history. By contrast, the direct developers show clear genetic impacts of their geographical histories. Despite extreme genetic subdivision within species, the direct developers B. vittatum and B. melanostoma have geographically coherent and complementary distributions, associated with biogeographical provinces. Thus, speciation appears to be driven by special biogeographical circumstances, rather than simply by genetic divergence of locally isolated populations. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 689–704. 相似文献
130.
Fayeza F Khan Danielle Carpenter Laura Mitchell Omniah Mansouri Holly A Black Jess Tyson John AL Armour 《BMC genomics》2013,14(1)