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861.
The population variability ofOrchis israelitica, O. caspia, and their intermediates, from two localities in Israel, was analyzed and illustrated by scatter diagram and hybrid index.
It is suggested that the hybrids are a result of introgression and are closer toO. caspia. Aspects of isolating barriers between these two species are discussed. 相似文献
862.
Varietal identification and assessment of genetic relationships in Hippeastrum using RAPD markers 总被引:2,自引:0,他引:2
The National Botanical Research Institute (NBRI) in Lucknow, India, maintains germplasm of Hippeastrum, a beautiful summer blooming ornamental. Germplasm collections comprise NBRI hybrids developed through selective breeding,
hybrids with unknown parentage, local species, and Dutch hybrids for research purposes. Considering the importance of protecting
plant breeders’ rights for commercial exploitation of hybrids, a PCR-based technique (random amplified polymorphic DNA—RAPD)
was used to correctly identify known and unknown hybrids and to determine cultivar relatedness. RAPD profiles were used very
successfully to trace and confirm the parentage of all the hybrids tested and to determine clear molecular relationships among
varieties. 相似文献
863.
Koei Kawakami Yoshiaki Matsui Tsutomu Ono Hiroyuki Ijima 《Biocatalysis and Biotransformation》2013,31(1):49-52
Proteases originating from Aspergillus melleus (Protease P) and Bacillus subtillis (Prolether FG-F) were entrapped into organic-inorganic hybrid silicates on Celite 545 by the sol-gel method, and their activities measured at 35°C for transesterification of chiral glycidol with vinyl n-butyrate in isooctane. n-Butyl- and dimethyl-substituted silicates provided 12.6 times higher activities with Protease P and 5.5 times with Prolether FG-F, respectively, than those deposited on Celite 545. Although pretreatment of those immobilized proteases with the chiral glycidol affected transesterification activities of both enantiomers, the ratio of the initial transesterification rate of (S)-(?)-glycidol to that of (R)-(+)-glycidol, remained unchanged. 相似文献
864.
DNA测序是生物信息学研究的重要内容之一,对测序序列的从头拼接是其中非常基础而重要的步骤.随着测序技术的不断更新,新的第三代测序数据拥有更长的序列长度、高错误率等性质,针对这些性质,同时使用二代、三代测序数据进行混合拼接是获得更好的拼接结果一种重要方式.本文介绍了现有的混合拼接软件的基本原理,并比较了不同软件拼接结果.... 相似文献
865.
866.
F. S. Nathoo 《Biometrics》2010,66(2):336-346
Summary In this article, we present a new statistical methodology for longitudinal studies in forestry, where trees are subject to recurrent infection, and the hazard of infection depends on tree growth over time. Understanding the nature of this dependence has important implications for reforestation and breeding programs. Challenges arise for statistical analysis in this setting with sampling schemes leading to panel data, exhibiting dynamic spatial variability, and incomplete covariate histories for hazard regression. In addition, data are collected at a large number of locations, which poses computational difficulties for spatiotemporal modeling. A joint model for infection and growth is developed wherein a mixed nonhomogeneous Poisson process, governing recurring infection, is linked with a spatially dynamic nonlinear model representing the underlying height growth trajectories. These trajectories are based on the von Bertalanffy growth model and a spatially varying parameterization is employed. Spatial variability in growth parameters is modeled through a multivariate spatial process derived through kernel convolution. Inference is conducted in a Bayesian framework with implementation based on hybrid Monte Carlo. Our methodology is applied for analysis in an 11‐year study of recurrent weevil infestation of white spruce in British Columbia. 相似文献
867.
868.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):520-530
Most non-steroidal anti-inflammatory drugs (NSAIDs) suffer from the deadlier gastrointestinal (GI) toxicities. The free -COOH group is responsible for the GI toxicity associated with all traditional NSAIDs. In the present research work, the main objective was to develop new chemical entities as potential anti-inflammatory agents with no GI toxicities. The results of synthesis and pharmacological screening of a series of hybrid molecules having general formula 2-(5-(5-(substituted phenyl)-2-oxo-ethylthio)-1,3,4-oxadiazole-2-yl)-2-phenyl-1H-indol-1-yl)-2-oxoethyl nitrate are described. These compounds were tested in vivo for their anti-inflammatory, analgesic, and ulcerogenic properties, and subjected to histopathological studies. Compound 7c, 2-(5-(5-(3-hydroxyphenyl)-2-oxo-ethylthio)-1,3,4-oxadiazole-2-yl)-2-phenyl-1H-indol-1-yl)-2-oxoethyl nitrate, was the most potent in this series. The compounds that showed significantly reduced GI ulcerogenicity also showed promising results in histopathological studies, and they were found to cause no mucosal injury. All the synthesized compounds were found to exhibit significant nitric oxide releasing activity in an in vitro method. In conclusion, the designed hybrid molecules were found to be significantly promising. 相似文献
869.
J.K. Deb Sundeep Malik V.K. Ghosh S. Mathai Renu Sethi 《FEMS microbiology letters》1990,71(3):287-292
Hybrids between a strain of Bacillus subtilis isolated in our laboratory and having the ability to degrade xylan and other complex polysaccharides and Corynebacterium acetoacidophilum, a lysine producer, were prepared by protoplast fusion. Based on distinctive parental biochemical characteristics the fusants were grouped into 9 categories, viz. BC1 through BC9. Three of the hybrids, BC5, BC7a and BC7b, were tested for their ability to produce xylanase and lysine. Both BC7a and BC7b produced xylanase but BC5 did not, however all of them produced lysine albeit to different degrees. These results demonstrate that intergeneric gene transfer takes place through protoplast fusion between these 2 important genera of bacteria and some of the fusants inherit the useful traits of both the parents. 相似文献
870.
R. K. BUTLIN G. M. HEWITT 《Biological journal of the Linnean Society. Linnean Society of London》1988,33(3):233-248
The grasshoppers Chorthippus parallelus parallelus and C. p. erythropus form a narrow hybrid zone in the Pyrenees. They differ in several characters of the pattern and structure of male stridulation and in the morphology of the stridulatory file. These characters are considered to be involved in the species' mate recognition system.
Crosses have been made between a Pyrenean C. p. erythropus population and two C. p. parallelus populations, one in the Pyrenees and one in the Massif Central. Reciprocal Fls and backcrosses have been examined for a set of stridulation and associated morphological characters. The crosses confirm that the subspecific differences have a genetic basis and suggest that they are polygenically determined. However the mode of inheritance is not simple. There is evidence for dominance and epistatic effects and for sex-linkage or maternal effects. Genetic correlations exist between some pairs of characters in the backcrosses.
These results are discussed in the context of the hybrid zone and in relation to the general problem of the evolutionary divergence of mate recognition systems. 相似文献
Crosses have been made between a Pyrenean C. p. erythropus population and two C. p. parallelus populations, one in the Pyrenees and one in the Massif Central. Reciprocal Fls and backcrosses have been examined for a set of stridulation and associated morphological characters. The crosses confirm that the subspecific differences have a genetic basis and suggest that they are polygenically determined. However the mode of inheritance is not simple. There is evidence for dominance and epistatic effects and for sex-linkage or maternal effects. Genetic correlations exist between some pairs of characters in the backcrosses.
These results are discussed in the context of the hybrid zone and in relation to the general problem of the evolutionary divergence of mate recognition systems. 相似文献