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排序方式: 共有259条查询结果,搜索用时 15 毫秒
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Berriman M Ghedin E Hertz-Fowler C Blandin G Renauld H Bartholomeu DC Lennard NJ Caler E Hamlin NE Haas B Böhme U Hannick L Aslett MA Shallom J Marcello L Hou L Wickstead B Alsmark UC Arrowsmith C Atkin RJ Barron AJ Bringaud F Brooks K Carrington M Cherevach I Chillingworth TJ Churcher C Clark LN Corton CH Cronin A Davies RM Doggett J Djikeng A Feldblyum T Field MC Fraser A Goodhead I Hance Z Harper D Harris BR Hauser H Hostetler J Ivens A Jagels K Johnson D Johnson J Jones K Kerhornou AX Koo H 《Science (New York, N.Y.)》2005,309(5733):416-422
African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified. 相似文献
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El-Sayed NM Myler PJ Bartholomeu DC Nilsson D Aggarwal G Tran AN Ghedin E Worthey EA Delcher AL Blandin G Westenberger SJ Caler E Cerqueira GC Branche C Haas B Anupama A Arner E Aslund L Attipoe P Bontempi E Bringaud F Burton P Cadag E Campbell DA Carrington M Crabtree J Darban H da Silveira JF de Jong P Edwards K Englund PT Fazelina G Feldblyum T Ferella M Frasch AC Gull K Horn D Hou L Huang Y Kindlund E Klingbeil M Kluge S Koo H Lacerda D Levin MJ Lorenzi H Louie T Machado CR McCulloch R 《Science (New York, N.Y.)》2005,309(5733):409-415
Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention. 相似文献
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Maria Luisa de la Torre Jose Antonio Grande Jorge Grai?o Tamara G??mez Juan Carlos Cer??n 《Water, air, and soil pollution》2011,216(1-4):3-19
With the aim of obtaining precise knowledge of the spatial?Ctemporal behavior of the chemistry of the river Tinto, both in the area of the headwaters, close to the point at which the acid mine drainage (AMD) pollution is carried into this river, and in the area before tidal influence, daily sampling was carried out from the end of October 2007 to the beginning of June 2008. In addition to pH, conductivity, and redox potential, sulfates, As, Cd, Fe, Cu, Zn, and Mn were determined for each sample. By studying the results obtained from the statistical processing applied, it can be deduced, first and foremost, that the river Tinto is a watercourse which is highly polluted by acid mine drainage throughout its length. It can also be determined that the order of abundance of the polluting elements, in terms of the concentration of the various parameters in milligrams per liter, follows the pattern, both in the generating source and the receiving environment: SO4 > Fe > Cu > Zn > Mn > Cd > As. The concentration values for As carried into the river in the generating source, with average values of 640???g?l?1 and with a maximum of 1,540???g?l?1 (ten times greater than the maximum found in the receiving environment), far exceed 10???g?l?1, the value established by the EU as the maximum permissible concentration in drinking water, as a consequence of the high eco-toxicity of this element. Specifically, in the correlation matrix, no correlation was found between the variables for both points. It can only be made out in the cross-correlation function graphs through low correlation, prior to time t?=?0, that pollution in the generating source leads to pollution in the receiving environment. 相似文献
147.
Jasmine E. Saros David W. Clow Tamara Blett Alexander P. Wolfe 《Water, air, and soil pollution》2011,216(1-4):193-202
Critical loads of nitrogen (N) from atmospheric deposition were determined for alpine lake ecosystems in the western US using fossil diatom assemblages in lake sediment cores. Changes in diatom species over the last century were indicative of N enrichment in two areas, the eastern Sierra Nevada, starting between 1960 and 1965, and the Greater Yellowstone Ecosystem, starting in 1980. In contrast, no changes in diatom community structure were apparent in lakes of Glacier National Park. To determine critical N loads that elicited these community changes, we modeled wet nitrogen deposition rates for the period in which diatom shifts first occurred in each area using deposition data spanning from 1980 to 2007. We determined a critical load of 1.4 kg N ha?1 year?1 wet N deposition to elicit key nutrient enrichment effects on diatom communities in both the eastern Sierra Nevada and the Greater Yellowstone Ecosystem. 相似文献
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Tamara A. Greasby Stephan R. Sain 《Journal of Agricultural, Biological & Environmental Statistics》2011,16(4):571-585
The goal of this work is to characterize the annual temperature for regional climate models. Of interest for impacts studies,
these profiles and the potential change in these profiles are a new way to describe climate change and the inherent uncertainty.
To that end, we propose a Bayesian hierarchical spatial model to simultaneously model the temperature profile for the four
seasons of the year, current and future. These profiles are then analyzed focusing on understanding how they change over time,
how they vary spatially, and how they vary between five different regional climate models. The results show that for temperature,
the regional models have different profile shapes depending on a number of factors including spatial location, driving climate
model, and regional climate model. This article has supplementary material online. 相似文献