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排序方式: 共有497条查询结果,搜索用时 15 毫秒
91.
92.
Zixiang Wen Yanlai Ding Tuanjie Zhao Junyi Gai 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(2):371-381
Annual wild soybean (Glycine soja Sieb. et Zucc.) is believed to be a potential gene source for future soybean improvement in coping with the world climate
change for food security. To evaluate the wild soybean genetic diversity and differentiation, we analyzed allelic profiles
at 60 simple-sequence repeat (SSR) loci and variation of eight morph-biological traits of a representative sample with 196
accessions from the natural growing area in China. For comparison, a representative sample with 200 landraces of Chinese cultivated
soybean was included in this study. The SSR loci produced 1,067 alleles (17.8 per locus) with a mean gene diversity of 0.857
in the wild sample, which indicated the genetic diversity of G. soja was much higher than that of its cultivated counterpart (total 826 alleles, 13.7 per locus, mean gene diversity 0.727). After
domestication, the genetic diversity of the cultigens decreased, with its 65.5% alleles inherited from the wild soybean, while
34.5% alleles newly emerged. AMOVA analysis showed that significant variance did exist among Northeast China, Huang-Huai-Hai
Valleys and Southern China subpopulations. UPGMA cluster analysis indicated very significant association between the geographic
grouping and genetic clustering, which demonstrated the geographic differentiation of the wild population had its relevant
genetic bases. In comparison with the other two subpopulations, the Southern China subpopulation showed the highest allelic
richness, diversity index and largest number of specific-present alleles, which suggests Southern China should be the major
center of diversity for annual wild soybean.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
93.
Mulberry dwarf (MD) is a serious infectious disease of mulberry caused by phytoplasma. Infection with MD phytoplasma results in stress phenotypes of yellowing, phyllody, stunting, proliferation, and witches' broom. Physiological and biochemical analysis has shown that infection with MD phytoplasma causes an increase in soluble carbohydrate and starch content, and a decrease in the net photosynthesis rate, carboxylation efficiency, and pigment content of leaves. Furthermore, damage to the chloroplast ultrastructure was detected in infected leaves. To better understand the pathogen‐stress response of mulberry (Morus alba L.) to MD phytoplasma, we conducted a comparative proteomic analysis using 2‐DE of infected and healthy leaves. Among 500 protein spots that were reproducibly detected, 20 were down‐regulated and 17 were up‐regulated. MS identified 16 differentially expressed proteins. The photosynthetic proteins rubisco large subunit, rubisco activase, and sedoheptulose‐1,7‐bisphosphatase showed enhanced degradation in infected leaves. Based these results, a model for the occurrence mechanism of MD is proposed. In conclusion, this study provides new insights into the mulberry response to MD phytoplasma infection. 相似文献
94.
Souza AC Acker CI Gai BM dos Santos Neto JS Nogueira CW 《Neurochemistry international》2012,60(4):409-414
The present study was conducted to evaluate the effect of 2-phenylethynyl-butyltellurium (PEBT), an organotellurium compound, at doses of 5 and 10 mg/kg on memory, employing the step-down inhibitory avoidance task in mice. Moreover, the involvement of glutamate uptake and release in cerebral cortex and hippocampus of mice was investigated. A single oral administration (p.o.) of PEBT at the dose of 10 mg/kg 1h before training (acquisition), immediately after training (consolidation) or 1 h before the test session (retrieval) of the step-down inhibitory avoidance task increased the step-through latency time in comparison to the control mice. In the open-field test, no significant differences in the number of crossings and rearings were observed among groups. The [(3)H]glutamate uptake by cerebral cortex and hippocampal slices of mice was significantly inhibited after 1h of treatment with PEBT. After 24h of PEBT exposure, only the hippocampal [(3)H]glutamate uptake was inhibited. The [(3)H]glutamate release by cerebral cortex and hippocampal synaptosomes of mice was not altered. These results suggest that PEBT improved memory stages (acquisition, consolidation and retrieval) in the step-down inhibitory avoidance task in mice. The improvement of memory by PEBT seems most likely to be mediated through an interaction with the amino acid transporters of the glutamatergic system. 相似文献
95.
采用双向凝胶电泳对水稻红莲型细胞质雄性不育的不育系小孢子发育单核期和二核期花药总蛋白进行了分离,通过银染显色,获得了分辨率和重复性较好的双向电泳图谱,且单核期和二核期花药总蛋白质在双向电泳胶上分布的图谱十分相似。PDQuest 2DE图像分析软件在等电点(pI)3.0~10.0、分子量(M.W.)9.0~98.0 kD之间可识别约1 800个蛋白质点。比较分析发现单核期和二核期花药中共有241个差异表达的蛋白质点,其中仅在单核期中表达的点数为125,仅在二核期中表达的为13点;表现为表达量差异的105点,其中在二核期表达下调的点数为70点,表达上调的为33点。还对蛋白质点集中的区域(pI 4.5~8.0,M.W.25.0~70.0 kD)中的41个差异蛋白质点进行了分子量和等电点分析。 相似文献
96.
97.
98.
采用定点克隆与随机克隆相结合的实验设计,用α~(35)S-dATP标记,以末端终止法测定了adr亚型乙型肝炎病毒DNA核心抗原基因的全顺序,包括终止密码子在内基因全长552核苷酸,编码由183氨基酸组成的多肽,计算分子量21000dlt。与日本及上海等实验室报道的adr亚型HBcAg基因比较,核苷酸点突变1.3—1.8%,由点突变导致的错义氨基酸突变有一处,占全部编码氨基酸的0.5%。与adw及ayw亚型比较,核苷酸点突变占全部核苷酸的9.8—10.9%,导致的错义突变占全部编码氨基酸的3.3—4.4%,并对eAg基因的定位进行了讨论。 相似文献
99.
Gai Liu Han Tian Yun-Qing Huang Jun Hu Yan-Xiao Ji Shao-Qing Li Yu-Qi Feng Lin Guo Ying-Guo Zhu 《The Journal of biological chemistry》2012,287(47):40051-40060
It has been suggested that the mitochondrial chimeric gene orfH79 is the cause for abortion of microspores in Honglian cytoplasmic male sterile rice, yet little is known regarding its mechanism of action. In this study, we used a mass spectrometry-based quantitative proteomics strategy to compare the mitochondrial proteome between the sterile line Yuetai A and its fertile near-isogenic line Yuetai B. We discovered a reduced quantity of specific proteins in mitochondrial complexes in Yuetai A compared with Yuetai B, indicating a defect in mitochondrial complex assembly in the sterile line. Western blotting showed that ORFH79 protein and ATP1 protein, an F1 sector component of complex V, are both associated with large protein complexes of similar size. Respiratory complex activity assays and transmission electron microscopy revealed functional and morphological defects in the mitochondria of Yuetai A when compared with Yuetai B. In addition, we identified one sex determination TASSELSEED2-like protein increased in Yuetai A, leading to the discovery of an aberrant variation of the jasmonic acid pathway during the development of microspores. 相似文献
100.
We present the first parsimony analysis of the agnathan subclass Galeaspida based on the analysis of 53 morphological characters.Three most parsimonious cladograms (126 steps in length;CI=0.508;RI=0.801)were discovered.An amended classification of the Galeaspida is proposed corresponding to the present analysis.Our results suggest that hanyangaspids,xiushuiaspids and dayongaspids from the Llandovery-Wenlock of Silurian are basal galeaspids.Within the remaining galeaspids,three major monophyletic groups (the Eugaleaspidiformes,the Polybranchiaspidiformes and the Huananaspidiformes)are well supported.It is shown that the dorsal fenestrae of the headshield evolved twice within the Galeaspida,one in the polybranchiaspidiform lineage,and the other in the huananaspidiform lineage (nested within the Huananaspidae).The chronological distribution of galeaspids highlights two radiations of the group,one for basal galeaspids and eugaleaspids in the Telychian (Llandovery)of Silurian,and the other for polybranchiaspidiforms and huananaspidiforms in the Lochkovian of Early Devonian. 相似文献