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101.
Effective small interfering RNAs and phosphorothioate antisense DNAs have different preferences for target sites in the luciferase mRNAs 总被引:7,自引:0,他引:7
Xu Y Zhang HY Thormeyer D Larsson O Du Q Elmén J Wahlestedt C Liang Z 《Biochemical and biophysical research communications》2003,306(3):712-717
Antisense DNA target sites can be selected by the accessibility of the mRNA target. It remains unknown whether a mRNA site that is accessible to an antisense DNA is also a good candidate target site for a siRNA. Here, we reported a parallel analysis of 12 pairs of antisense DNAs and siRNA duplexes for their potency to inhibit reporter luciferase activity in mammalian cells, both of the antisense DNA and siRNA agents in a pair being directed to same site in the mRNA. Five siRNAs and two antisense DNAs turned out to be effective, but the sites targeted by those effective siRNAs and antisense DNAs did not overlap. Our results indicated that effective antisense DNAs and siRNAs have different preferences for target sites in the mRNA. 相似文献
102.
MLC_2-糜酶融合基因克隆及转基因小鼠的产生 总被引:2,自引:0,他引:2
为研究糜酶基因在体内的结构与功能以及与心肌肥厚的关系,并提高糜酶基因在小鼠心脏中的表达,构建肌球蛋白轻链-2启动子(myosinlightchain-2promoter,MLC2)-糜酶融合基因并产生转基因小鼠.通过删除糜酶基因启动子序列,构建结构基因克隆,然后与大鼠心脏肌球蛋白轻链-2启动子序列相拼接,构建MLC2-糜酶融合基因克隆,回收并纯化融合基因片段,显微注射入小鼠受精卵产生转基因小鼠,经PCR扩增、Southern印迹杂交和PCR扩增产物的测序,筛选和确定转基因鼠.在新出生的46只小鼠中有2只为转基因阳性鼠,且外源基因能稳定遗传给后代,从而获得了可用于研究糜酶基因在体内的结构与功能以及与心肌肥厚的关系的转基因小鼠模型. 相似文献
103.
CD3ε和PMA对fas基因转录调控作用的研究 总被引:2,自引:0,他引:2
研究了CD3ε和PMA对细胞凋亡基因fas的转录调控作用.根据已知的人fas基因5'上游序列设计引物,用PCR法从人胸腺细胞基因组DNA中扩增出fas5'上游长为446bp的启动子片段.将此片段定向克隆到以虫荧光素酶为报告基因的真核细胞表达载体pXP2中.经限制性内切酶酶切鉴定及序列测定分析表明此重组表达质粒DNA的结构和序列正确.用此质粒(pXP2-fasup)瞬时转染人JurkatT淋巴细胞,分析报告基因的表达水平.结果表明fas基因上游-506到-60的区域有弱启动子活性,约是阴性对照的1.5倍.抗CD3ε抗体和PMA处理均可增强fas启动子的活性,促进报告基因的表达,其虫荧光素酶活性分别是未经处理的pXP2-fasup转染细胞的1.7倍和3.3倍,但二者没有协同作用.PKC的抑制剂staurosporine和PTK的抑制剂herbimycinA可抑制PMA诱导的fas基因转录,使虫荧光素酶基因的表达降至未用PMA处理的水平.但PTK的另一种抑制剂genistein可与PMA发挥协同作用,上调fas基因的转录,使虫荧光素酶活性增加到5倍.这些结果为阐明CD3ε及PMA介导T淋巴细胞激活和凋亡的分子机制 相似文献
104.
Stoesser G Baker W van den Broek A Garcia-Pastor M Kanz C Kulikova T Leinonen R Lin Q Lombard V Lopez R Mancuso R Nardone F Stoehr P Tuli MA Tzouvara K Vaughan R 《Nucleic acids research》2003,31(1):17-22
The EMBL Nucleotide Sequence Database (http://www.ebi.ac.uk/embl/) incorporates, organizes and distributes nucleotide sequences from all available public sources. The database is located and maintained at the European Bioinformatics Institute (EBI) near Cambridge, UK. In an international collaboration with DDBJ (Japan) and GenBank (USA), data are exchanged amongst the collaborating databases on a daily basis to achieve optimal synchronization. Webin is the preferred web-based submission system for individual submitters, while automatic procedures allow incorporation of sequence data from large-scale genome sequencing centres and from the European Patent Office (EPO). Database releases are produced quarterly. Network services allow free access to the most up-to-date data collection via FTP, Email and World Wide Web interfaces. EBI's Sequence Retrieval System (SRS) integrates and links the main nucleotide and protein databases plus many other specialized molecular biology databases. For sequence similarity searching, a variety of tools (e.g. Fasta, BLAST) are available which allow external users to compare their own sequences against the latest data in the EMBL Nucleotide Sequence Database and SWISS-PROT. All resources can be accessed via the EBI home page at http://www.ebi.ac.uk. 相似文献
105.
106.
Yanhui Liu Guohui Zhang Yulong Guan Xiaoliang Zhao Quan Wang Hua Li Jinhong Qi 《Journal of cellular and molecular medicine》2020,24(18):10615-10620
The case‐control study was designed to investigate the genetic effects of interferon‐gamma (IFN‐γ) rs2069727 and rs1861494 polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese Han population. Blood samples were collected from 108 AS patients and 110 healthy controls. IFN‐γ polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Hardy‐Weinberg equilibrium (HWE) test was performed in control group. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using chi‐square test to evaluate the association between AS susceptibility and IFN‐γ polymorphisms, and the results were adjusted by logistic regressive analysis. The frequency of rs2069727 CC genotype was much higher in cases than that in controls, suggested its significant association with increased AS risk (adjusted OR = 5.899, 95% CI = 1.563‐22.261; P = .009). In addition, C allele also showed close association with increased risk of AS (adjusted OR = 2.052, 95% CI = 1.286‐1.704, P = 0 .003). While the genotype and allele frequencies of IFN‐γ rs1861494 polymorphism were not significantly different between patients and controls (P > 0.05 for all), IFN‐γ rs2069727 polymorphism is significantly associated with increased AS risk in a Chinese Han Population. 相似文献
107.
Xin Li Dawei Li Pengfei Lv Jinyan Hu Quan Feng Qufu Wei 《Engineering in Life Science》2019,19(11):815-824
In this study, 2‐hydroxyethyl methacrylate (HEMA) was used as the monomers for surface grafting on electrospun PU/RC nanofiber membrane via atom transfer radical polymerization (ATRP) method, and the PU/RC‐poly(HEMA) nanofiber membrane was investigated as a carrier for LAC. Free and immobilized LAC was characterized, and efficiency of bisphenol A (BPA) removal was determined. The results indicated that the PU/RC‐poly(HEMA)‐LAC showed relatively higher pH stability, temperature stability, and storage stability than free and PU/RC‐LAC; moreover, more than 60% of the PU/RC‐poly(HEMA)‐LAC activity was retained after 10 cycles of ABTS treatment. Notably, the BPA removal efficiency of PU/RC‐poly(HEMA)‐LAC membrane generally ranged from 87.3 to 75.4% for the five cycles. Therefore, the PU/RC‐poly(HEMA) nanofiber membrane has great potential as a carrier for the LAC immobilization for various industrial applications and bioremediation. 相似文献
108.
Abu Dayyeh BK Quan TK Castro M Ruby SW 《The Journal of biological chemistry》2002,277(23):20221-20233
Pre-mRNA binding to the yeast U2 small nuclear ribonucleoprotein (snRNP) during prespliceosome formation requires ATP hydrolysis, the highly conserved UACUAAC box of the branch point region of the pre-mRNA, and several factors. Here we analyzed the binding of a radiolabeled 2'-O-methyl oligonucleotide complementary to U2 small nuclear RNA to study interactions between the UACUAAC box, U2 snRNP, and Prp5p, a DEAD box protein necessary for prespliceosome formation. Binding of the 2'-O-methyl oligonucleotide to the U2 snRNP in yeast cell extract was assayed by gel electrophoresis. Binding was rapid, enhanced by ATP, and dependent on the integrity and conformation of the U2 snRNP. It was also stimulated by Prp5p that was found to associate physically with U2 snRNP. In vitro heat inactivation of the temperature-sensitive prp5-1 mutant extract decreased oligonucleotide binding to U2 and the ATP enhancement of binding by 3-fold. Furthermore, the temperature-sensitive prp5-1 mutation maps to the ATP-binding motif I within the helicase-like domain. Thus the catalytic activity of Prp5p likely promotes a conformational change in the U2 snRNP. 相似文献
109.
110.