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991.
Effect of body size on the standard metabolism of horse mackerel 总被引:11,自引:0,他引:11
The routine metabolic rate R R and standard metabolic rate R S were measured in horse mackerel Trachurus trachurus at 13°C over weight range of 1·4–390 g. A data extraction method rather than the more commonly used method of extrapolating the swimming speed-metabolic rate curves back to zero swimming speed was developed to measure the R S . The relation between R R and R S and weight was expressed as a linear regression with the log transformed data. The mean slope of the regression was 0·752 for R S and 0·725 for R S . 相似文献
992.
Edaphic microsatellite DNA divergence in wild emmer wheat, Triticum dicoccoides, at a microsite: Tabigha, Israel 总被引:1,自引:0,他引:1
Y. C. Li T. Fahima J. H. Peng M.S. Röder V. M. Kirzhner A. Beiles A. B. Korol E. Nevo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(7):1029-1038
Twenty eight microsatellite markers were used to analyze genetic divergence in tandem dinucleotide repeated DNA regions between
two edaphic subpopulations of Triticum dicoccoides growing on the contrasting terra rossa and basalt soilsfrom a microsite at Tabigha, north of the Sea of Galilee, Israel. The
terra rossa soil niche was drier and more stressful than the basalt throughout the growing season (November to May). Significant
microsatellite divergence in allele distribution, repeat length, genetic diversity, and linkage disequilibria were found between
emmer wheat from the two soil types over two short transects of 100 m each. Soil-specific and -unique alleles and linkage disequilibria were observed in the terra rossa and basalt subpopulations. A permutation test showed that
the effects of random genetic drift were very low for the significant genetic diversity at microsatellite loci between the
two subpopulations, suggesting that an adaptive molecular pattern derived by edaphic selection may act upon variation of the
microsatellites.
Received: 4 February 2000 / Accepted: 31 March 2000<@head-com-p1a.lf>Communicated by H.F. Linskens 相似文献
993.
野葛组织内抗氧化物质初步分析 总被引:4,自引:0,他引:4
分别测定了野葛根、茎、叶SOD、CAT、POD、GSH、Px、Vc抗氧化物质活性,其中叶组织中含量最高;测定可深远的性蛋白和可溶性糖含量。发现可溶蛋白叶中最高,但根中可溶性糖含量远远高于茎叶。实验表明,野葛叶中也含有丰富的抗氧化物质,值得进一步研究开发。 相似文献
994.
A higher level of salt tolerance in saline populations of wild soybean ( Glycine soja Sieb. et Zucc. ) has been found in the Yellow River Delta. The levels of salt tolerance for individuals with in populations vary widely. In the saline populations, there are a few plants with much higher tolerant level than that of the most tolerant cultivars, such as Morgan, and others as saline sensitive plants. Isozyme analysis showed a high level of genetic diversity, however, no relationship was found between isozymatic patterns and salt tolerance. Saline and normal populations shared similar genetic structure with a genetic distance of 0. 045. By using a modified procedure of random amplified polymorphic DNA(RAPD), a higher level of DNA diversity was detected in saline populations. The authors propose that the high level of genetic diversity and developmental flexibility is responsible for adaptation of wild soybean to changing saline conditions. 相似文献
995.
T. Fahima G. L. Sun A. Beharav T. Krugman A. Beiles E. Nevo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):434-447
Genetic diversity in random amplified polymorphic DNAs (RAPDs) was studied in 110 genotypes of the tetraploid wild progenitor
of wheat, Triticum dicoccoides, from 11 populations sampled in Israel and Turkey. Our results show high level of diversity of RAPD markers in wild wheat
populations in Israel. The ten primers used in this study amplified 59 scorable RAPD loci of which 48 (81.4%) were polymorphic
and 11 monomorphic. RAPD analysis was found to be highly effective in distinguishing genotypes of T. dicoccoides originating from diverse ecogeographical sites in Israel and Turkey, with 95.5% of the 100 genotypes correctly classified
into sites of origin by discriminant analysis based on RAPD genotyping. However, interpopulation genetic distances showed
no association with geographic distance between the population sites of origin, negating a simple isolation by distance model.
Spatial autocorrelation of RAPD frequencies suggests that migration is not influential. Our present RAPD results are non-random
and in agreement with the previously obtained allozyme patterns, although the genetic diversity values obtained with RAPDs
are much higher than the allozyme values. Significant correlates of RAPD markers with various climatic and soil factors suggest
that, as in the case of allozymes, natural selection causes adaptive RAPD ecogeographical differentiation. The results obtained
suggest that RAPD markers are useful for the estimation of genetic diversity in wild material of T. dicoccoides and the identification of suitable parents for the development of mapping populations for the tagging of agronomically important
traits derived from T. dicoccoides.
Received: 13 July 1998 / Accepted: 13 August 1998 相似文献
996.
J. H. Peng T. Fahima M. S. Röder Y. C. Li A. Dahan A. Grama Y. I. Ronin A. B. Korol E. Nevo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):862-872
Stripe rust caused by Puccinia striifomis West. is one of the most devastating diseases relating to wheat production. Wild emmer wheat, Triticum dicoccoides, the tetraploid progenitor of cultivated wheat, has proven to be a valuable source of novel stripe-rust resistance genes
for wheat breeding. For example, T. dicoccoides accessions from Mt. Hermon, Israel, are uniformly and highly resistant to stripe-rust. The main objective of the present
study is to map a stripe-rust resistance gene, derived from the unique Mt. Hermon population of wild emmer, using microsatellite
markers. An F2 mapping population was established by crossing stripe-rust resistant T. dicoccoides accession H52 from Mt. Hermon with the Triticum durum cultivar Langdon. The stripe-rust resistance derived from accession H52 was found to be controlled by a single dominant gene
which was temporarily designated as YrH52. Out of 120 microsatellite markers tested, 109 (91%) showed polymorphism between the parental lines. Among 79 segregating
microsatellite loci generated from 56 microsatellite primer pairs, nine were linked to YrH52 with recombination frequencies of 0.02–0.35, and LOD scores of 3.56–54.22. A genetic map of chromosome 1B, consisting of
ten microsatellite loci and the stripe-rust resistance gene YrH52, was constructed with a total map length of 101.5 cM. YrH52 is also closely linked to RFLP marker Nor1 with a map distance of 1.4 cM and a LOD value of 29.62. Apparent negative crossover interference was observed in chromosome
1B, especially in the region spanning the centromere. Negative crossover interference may be a common characteristic of gene-rich
regions or gene clusters in specific chromosomes.
Received: 30 October 1998 / Accepted: 2 November 1998 相似文献
997.
D. Bartsch N. C. Ellstrand 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(7-8):1120-1130
The genus Beta L. is a morphologically and genetically variable group composed of wild, weedy, and domesticated forms that are used for
sugar production or as vegetables. In this study, we have evaluated genetic variation in 64 germplasm accessions of wild and
domesticated beets and examined the origin of wild beet accessions in California using allozyme analysis. UPGMA analysis showed
overall that domesticated and wild beets form genetically coherent groups. Wild beets in California have two different origins,
from European Beta vulgaris or from Beta macrocarpa. Population-level patterns of allozyme variation for wild California beets related to B. vulgaris suggest that those populations evolved from naturalized populations of the cultivated B. vulgaris ssp. vulgaris which had hybridized to varying degrees with the sea beets B. vulgaris ssp. maritima. Wild California beets related to B. macrocarpa are essentially genetically identical to European accessions. In addition, we found substantial evidence for hybridization
and introgression of B. vulgaris alleles in one B. macrocarpa accession in California. The obligate outcrosser B. vulgaris exhibits more allelic diversity than the self-compatible B. macrocarpa.
Beta vulgaris ssp. maritima exhibits more genetic diversity than domesticated B. vulgaris ssp. vulgaris.
Received: 2 November 1998 / Accepted: 29 April 1999 相似文献
998.
围栏条件下社鼠的食物贮藏行为 总被引:3,自引:0,他引:3
在北京东灵山地区, 用活捕笼从野外捕获社鼠, 并在野外建造围栏, 以山杏种子和辽东栎坚果为备选食物, 对围栏条件下社鼠的食物贮藏行为进行了研究。数据的统计分析采用SPSS for Windows (version 1010) 进行。结果表明: 1) 社鼠主要表现出食物的集中贮藏方式; 2) 贮藏食物被模拟盗窃使社鼠的食物贮藏活动加强; 3)社鼠倾向于选择山杏种子进行贮藏, 而对辽东栎坚果则取食较多。文中还讨论了食物类型、模拟盗窃等因素对社鼠食物贮藏行为的影响。 相似文献
999.
冬季清凉峰山区小麂和野猪的生境选择及差异 总被引:4,自引:3,他引:1
从2005 年11 月5 日至2006 年1 月21 日,为了评估小麂和野猪的生境选择及其差异,我们在浙江清凉峰国家级自然保护区核心区共设置了248 个样方群。研究发现,两者都选择平缓坡的灌丛植被、草本密度小、离住宅较近和离隐蔽物距离适中的生境,表现了它们的生境选择有一定的重叠性。但是它们也表现出生境选择的一些差异,小麂选择乔木密度适中、灌丛密度大和郁闭度适中的生境,而野猪选择乔木密度小的生境,随机地使用各类灌丛密度和郁闭度的生境。小麂还选择北坡、离水源距离较远的生境,野猪只是随机地使用不同的坡向和离水源距离的生境。分析两者共存的机制,我们发现小麂采取隐藏策略而野猪采取逃跑策略来避敌和利用资源,即它们之间存在与反捕食策略相关的生境选择差异。
相似文献
相似文献
1000.
Gastric evacuation experiments were performed on horse mackerel Trachurus trachurus. A nearly full matrix experimental design with respect to the variables predator weight (<10–400 g) meal size (up to 7·8% body weight) and temperature (10–20°) was covered with 0-group smelt Osmerus eperlanus as prey. A general evacuation model without meal size as a variable was fitted to the data on wet weights as well as on dry weights by means of non-linear regression technique. Two methods of data transformation, relative data and square root transformation, were applied to improve variance homogeneity. The most reliable model fit was achieved on dry weight data applying the square root transformation technique: where St =stomach content (g wet weight) at time t after ingestion, S0 =the initial meal size, W =predator (g wet weight), and T =temperature. The estimated coefficient of the exponential temperature function, δ=00·032, corresponds to a Q 10 value of 1·4 which is outstandingly low in comparison with results on other species. However additional experiments to determine maximum daily food rations indicated that appetite in contrast to gastric evacuation is strongly temperature dependent. 相似文献