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941.
Stearoyl-CoA Desaturase (SCD) Gene Polymorphism in Goat Breeds 总被引:1,自引:0,他引:1
Chun-Lei Zhang Xue-Yuan Gao Ru-Ying Shao Yan-Hong Wang Xing-Tang Fang Hong Chen 《Biochemical genetics》2010,48(9-10):822-828
942.
Somatic embryogenesis (SE) was successfully induced from mature zygotic embryos of seven families of Picea likiangensis (Franch.) Pritz after 20 weeks culture on initiation medium. Three basal media (one-half strength LM medium, one-half strength
LP medium and improved LP medium) with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine
(6-BA) were tested but only one-half strength LM medium supplemented with 2,4-D and 6-BA was successful for the embryogenic
cultures (EC) initiation. The initiation frequencies of EC varied greatly from different families when culturing on the same
initiation medium. The highest frequency (41.3%) was induced from one of the families on one-half strength LM medium supplemented
with 3 mg L−1 2,4-D and 1.5 mg L−1 6-BA and 16.83% on average for seven families. EC were subcultured and proliferated on the same medium as the initiation
one every 10 days. 3 lines of EC induced from the same family were applied in maturation experiment. Cotyledonary somatic
embryos were observed after EC were transferred to maturation media of one-half strength LM medium containing 20-80 mg L−1 abscisic acid and 7.5% polyethylene glycol (PEG-4000). However, one-half strength LM medium supplemented with 40 mg L−1 or 60 mg L−1 ABA and 7.5% PEG gave the best maturation and the 3 lines showed different ability in maturation. Over 80% cotyledonary somatic
embryos germinated normally on DCR medium containing 0.2% activated carbon. The success on SE induction of the species has
provided an effective clonal propagation method for this important tree’s genetic improvement. 相似文献
943.
Linsheng Liu Jiye Aa Guangji Wang Bei Yan Xinwen Wang Bei Cao Mengjie Li Yuanting Zheng Fang Zhou Zimei Wu 《Analytical biochemistry》2010,406(2):105-6697
In metabolomic research, blood plasma and serum have been considered to possess similar compositions and properties. Their perceived equivalence has resulted in researchers choosing arbitrarily between serum and plasma for analysis. Here, routine serum and plasma were prepared and their low-molecular-weight compounds were determined using gas chromatography/time-of-flight mass spectrometry. Principal components analysis was applied to process the acquired data, and marked differences in metabolite profiles were observed between serum and plasma. Of the 72 identified compounds, 36 (50%) discriminate serum from plasma, with 29 and 7 metabolites showing a significantly higher abundance (t test, P < 0.05) in serum and plasma, respectively. Incubation of blood had distinct effects on the analyte peak areas, with the effects being more pronounced for plasma than for serum and more pronounced for a shorter incubation than for a longer incubation. These results highlight the importance in choosing serum or plasma as the analytical sample and in stipulating the incubation time. Because incubation affected the analyte peak areas less in serum than in plasma, we recommend serum as the sample of choice in metabolomic studies. 相似文献
944.
Chia-Cheng Hung Shee-Uan Chen Shin-Yu Lin Mei-Ya Fang Yi-Yi Tsai Yu-Shih Yang Yi-Ning Su 《Analytical biochemistry》2010,400(1):69-77
Preimplantation genetic diagnosis (PGD) is employed increasingly to allow transfer of embryos to the uterus in assisted reproduction procedures. There are three stages of biopsy: polar bodies, one or two blastomeres from the cleavage-stage embryos, and trophectoderm cells (∼5 cells) from the blastocyst-stage embryos. Validation of polymerase chain reaction (PCR)-based assays are challenging because only limited genetic material can be obtained for PGD. In the current study, we modified a valid single-cell PCR protocol for PGD using real-time PCR assay with fluorescence resonance energy transfer (FRET) hybridization probes followed by melting curve analysis. We optimized and clinically applied the protocol, permitting molecular genetic analysis to amplify a specific region on the beta-globin (HBB) gene for a couple, carriers of two mutations: c.-78A>G and c.52A>T. Among a total of eight embryos obtained after ovarian stimulation, a single blastomere per embryo at the six- to eight-cell stage was biopsied. This PGD method showed that four embryos were unaffected, two embryos were selected for transfer, and one pregnancy was achieved. Finally, a healthy male baby was delivered at 38 weeks’ gestation. The results obtained using the new method, FRET hybridization probes, were compared with findings using an existing method, primer extension minisequencing. 相似文献
945.
Y. L. Jiao L. H. Wang B. H. Jiao S. J. Wang Y. W. Fang S. Liu 《Applied Biochemistry and Microbiology》2010,46(2):148-153
The function of a new starter unit acyltransferase (SAT) domain SAT-EF080951 (GenBank accession number) encoded in a new type I polyketide synthase (PKS) gene cluster EF568935 (GenBank accession number) isolated for this study was analyzed by domain replacement with an extender unit AT (EAT) domain of avermectin PKS. It was shown that the SAT-EF080951 incorporated malonyl-CoA specifically in vivo, which contradicted the specificity that we had previously determined by substrate binding test in vitro. The result of this study indicates that type I PKS-SAT can alter its specificity in vivo and functions well in extender units and proved the feasibility of the SAT-EAT domain replacement in type I PKS. We propose that SAT-EAT replacement strategy could be a novel route for increasing the diversity of new polyketides combinatorially biosynthesized. The new type I PKS-SAT-EF080951 studied herein may be further employed for related studies on enzymology or combinatorial biosynthesis of polyketides. 相似文献
946.
目的:研究HLA-DRB1基因多态性与新疆哈萨克族人群结核病(TB)的相关性。方法:采用病例-对照的研究方法,应用聚合酶链反应-序列特异性引物(PCR-SSP)技术对231例新疆哈萨克族肺结核患者和230例新疆哈萨克族健康对照者的13个HLA-DRB1等位基因进行分型,比较其等位基因频率(GF)并计算其比值比(OR)。结果:与新疆哈萨克族人群对照组相比,新疆哈萨克族人群结核病例组中HLA-DRB1*04显著增高(11.72%比6.75%,p0.05,OR=1.889),HLA-DRB1*10也增高(2.86%比1.09%),但统计学上无显著性差异(Pc0.05)。结论:HLA-DRB1*04可能是新疆哈萨克族人群结核病的易感基因。 相似文献
947.
The diploid species Brassica rapa(genome AA)and B.oleracea(genome CC)were compared by fuU-seale proteome analyses of seedling.A total of 28.2% of the proteins was common to both species,indicating the existence of a basal or ubiquitous proteome.How-ever,a number of discriminating proteins(32.0%)and specific proteins(39.8%)of the Brassica A and C genomes,respectively,were identified,which could represent potentially species-specific functions.Based on these A or C genome-specific proteins,a number of PCR-based markers to distinguish B.rapa and B.oleracea species were also developed. 相似文献
948.
葡萄SBP基因家族生物信息学分析 总被引:5,自引:0,他引:5
SBP(squamosa promoter binding protein,SBP)基因家族是植物所特有的一类重要转录因子,广泛参与植物生长、发育以及多种生理生化反应的信号传导。葡萄是继拟南芥、水稻和杨树之后完成全基因组测序的第四种开花植物,因此葡萄逐渐成为分子生物学研究的重点对象,进行葡萄基因组信息挖掘与分析对于葡萄功能基因组学的发展具有重要意义。本文利用生物信息学方法对葡萄家族45条SBP蛋白序列的系统发生和SBP基因组定位进行分析,然后对其氨基酸组成成分、理化性质以及二级和三级结构进行预测和分析,同时还分析了葡萄与拟南芥的SBP基因家族之间的联系。结果显示这45条蛋白序列与拟南芥16个SBP基因蛋白序列一起分成了3个亚族,说明拟南芥与葡萄SBP基因间具有较高的保守性;进一步的基因组定位结果发现其分布在14条染色体上,较拟南芥在染色体上的分布更为分散。研究还发现不同亚家族间氨基酸数目、氨基酸序列间的疏水性存在一定的差异;而二级结构预测结果发现,41条氨基酸序列以随机卷曲为主要组成部分,这与拟南芥相似,且45条氨基酸序列三维结构十分相似。本文实验结果均为葡萄SBP基因家族的进一步功能分析提供了重要研究基础。 相似文献
949.
Huang Huang Na Wei Yingfei Xiong Feng Yang Huaqiang Fang Wenjun Xie Zhuan Zhou Heping Cheng Zicai Liang Quan Du 《生物学前沿》2010,5(3):272-281
To modulate gene expression in research studies or in potential clinical therapies, transfection of exogenous nucleic acids
including plasmid DNA and small interference RNA (siRNA) are generally performed. However, the cellular processing and the
fate of these nucleic acids remain elusive. By investigating the cellular behavior of transfected nucleic acids using confocal
imaging, here we show that when siRNA was co-transfected into cultured cells with other nucleic acids, including single-stranded
RNA oligonucleotides, single and double-stranded DNA oligonucleotides, as well as long double-stranded plasmid DNA, they all
aggregate in the same cytoplasmic granules. Interestingly, the amount of siRNA aggregating in granules was found not to correlate
with the gene silencing activity, suggesting that assembly of cytoplasmic granules triggered by siRNA transfection may be
separable from the siRNA silencing event. Our results argue against the claim that the siRNA-aggregating granules are the
functional site of RNA interference (RNAi). Taken together, our studies suggest that, independent of their types or forms,
extraneously transfected nucleic acids are processed through a common cytoplasmic pathway and trigger the formation of a new
type of cytoplasmic granules “transfection granules”. 相似文献