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991.
992.
Samir Kumar Roy Yasunori Chiba Yoshifumi Jigami 《Biotechnology and Bioprocess Engineering》2000,5(4):219-226
The application of recombinant DNA technology to restructure metabolic networks can change metabolite and protein products
by altering the biosynthetic pathways in an organism. Although some success has been achieved, a more detailed and thorough
investigation of this approach is certainly warranted since it is clear that such methods hold great potential based on the
encouraging results obtained so far. In last decade, there have been tremendous advances in the field of glycobiology and
the stage has been set for the biotechnological production of glycoproteins for therapeutic use. Today glycoproteins are one
of the most important groups of pharmaceutical products. In this study the attempt was made to focus on identifying technologies
that may have general application for modifying glycosylation pathway of the yeast cells in order to produce glycoproteins
of therapeutic use. The carbohydrates of therapeutic recombinant glycoproteins play very important roles in determining their
pharmacokinetic properties. A number of biological interactions and biological functions mediated by glycans are also being
targeted for therapeutic manipulationin vivo. For a commercially viable production of therapeutic glycoproteins a metabolic engineering of a host cell is yet to be established. 相似文献
993.
S Koizumi T Endo K Tabata H Nagano J Ohnishi A Ozaki 《Journal of industrial microbiology & biotechnology》2000,25(4):213-217
A large-scale production system of GDP-fucose (GDP-Fuc) and fucosylated oligosaccharides was established by the combination
of recombinant Escherichia coli cells overexpressing GDP-Fuc biosynthetic genes and Corynebacterium ammoniagenes cells. E. coli cells overexpressed the genes for glucokinase, phosphomannomutase, mannose-1-phosphate guanylyltransferase, GDP-mannose (GDP-Man)
dehydratase, and GDP-4-keto-6-deoxy-mannose (GKDM) epimerase/reductase as well as phosphoglucomutase and phosphofructokinase.
C. ammoniagenes contributed to the formation of GTP from GMP. GDP-Fuc accumulated to 29 mM (18.4 g l−1) after a 22-h reaction starting with GMP and mannose through introducing the two-step reaction to overcome the inhibition
of GDP-Fuc on GDP-Man dehydratase activity. When E. coli cells overexpressing the α1,3-fucosyltransferase gene of Helicobacter pylori were put into the GDP-Fuc production system, Lewis X [Galβ1–4(Fucα1–3)GlcNAc] was produced at an amount of 40 mM (21 g l−1) for 30 h from GMP, mannose, and N-acetyl lactosamine. The production system through bacterial coupling can be applied to the industrial manufacture of fucosylated
oligosaccharides. Journal of Industrial Microbiology & Biotechnology (2000) 25, 213–217.
Received 01 May 2000/ Accepted in revised form 20 July 2000 相似文献
994.
995.
Short of a complete genomic DNA sequence, sequence tagged sites (STSs) have emerged as major genomic reagents for the genetic
analysis of little-studied ecologically and agriculturally important organisms. Here, we report STS developed for the turkey
(Meleagris gallopavo), guinea fowl (Numidea meleagris), Japanese quail (Coturnix coturnix) and pigeon using primers specific for reference DNA sequences of two chicken (Gallus gallus) genes, aggrecan (agc1) and type X collagen (col10). Additional STSs were also developed for turkey, quail and chicken using primers specific for the human apobec-1 gene. The total length of the STSs developed was 5990, 2522, 4127, 1539 and 6600 bp for the turkey, guinea fowl, Japanese
quail, pigeon and chicken, respectively. Based on splice site consensus GT and AG sequences, four of the seven agc1-based chicken STS appear to contain introns. The human gene-based STSs showed no significant sequence identity with the
reference GenBank sequences. Maximum likelihood, maximum parsimony and neighbour-joining analysis of an agc1-based STS that was common to all five species showed phylogenetic relationships consistent with those previously defined
using mitochondria DNA sequences and nuclear gene restriction maps. Additionally, several putative single nucleotide polymorphisms
(SNPs) were detected within the STSs, including eight in the turkey, two in the quail, and two in the chicken when multiple
sequences were evaluated from each species. This report describes new STSs that are resources for genetic and physical mapping
and genome analysis within and among avian species. These resources should further aid in our understanding of the biology
of agriculturally important but little-studied guinea fowl and turkey.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
996.
【背景】物种间相互作用是物种进化的重要推动力,然而如何将基因型和表型关联以及确定在物种相互作用过程中起重要作用的基因均面临挑战。【目的】通过系统作图(Systems mapping)得到两种微生物在相互作用过程中起重要作用的SNPs (Single nucleotide polymorphism),以及随着时间的变化,这些SNPs是如何相互联系进而影响大肠埃希菌和金黄色葡萄球菌的相互作用。【方法】分别对45株大肠埃希菌、45株金黄色葡萄球菌进行单独培养和混合共培养,通过实时荧光定量PCR(Real-time quantitative PCR,qPCR)进行绝对定量,得到一定时间内各个菌株的生长量,比较相同菌株在不同培养条件下生长情况,以各个菌株重测序结果为基础,结合系统作图得到在相互作用过程中起重要作用的显著SNPs及其相互联系。【结果】通过系统作图分析,获得具有54对显著SNPs组合的三维曼哈顿图,这些组合中41个显著SNPs来自大肠埃希菌,12个显著SNPs来自金黄色葡萄球菌。在上述SNPs中已有6个SNPs所在的候选基因都可以直接或者间接影响微生物的生长量变化,从而影响两种微生物相互作用方式。它们分别是nhaR(E19056)参与生物膜的形成,rhlE(E832164)与核糖体的组装有关,csiD (E2789300)的表达可以使细胞面对恶劣环境,alk B (E2309274)可以参与DNA的损伤修复,sucA(E759230)和yjjW(E4614704)都参与细胞的代谢过程。【结论】系统作图可以检测到物种在相互作用过程中显著SNPs;物种相互作用过程中不同SNPs遗传效应随着时间变化;细菌的相互作用过程是直接遗传效应、间接遗传效应和上位性效应共同产生的结果。 相似文献
997.
998.
999.
Replication study of 34 common SNPs associated with prostate cancer in the Romanian population 下载免费PDF全文
Viorel Jinga Irma Eva Csiki Andrei Manolescu Paul Iordache Ioan Nicolae Mates Daniel Radavoi Stefan Rascu Daniel Badescu Paula Badea Dana Mates 《Journal of cellular and molecular medicine》2016,20(4):594-600
Prostate cancer is the third‐most common form of cancer in men in Romania. The Romanian unscreened population represents a good sample to study common genetic risk variants. However, a comprehensive analysis has not been conducted yet. Here, we report our replication efforts in a Romanian population of 979 cases and 1027 controls, for potential association of 34 literature‐reported single nucleotide polymorphisms (SNPs) with prostate cancer. We also examined whether any SNP was differentially associated with tumour grade or stage at diagnosis, with disease aggressiveness, and with the levels of PSA (prostate specific antigen). In the allelic analysis, we replicated the previously reported risk for 19 loci on 4q24, 6q25.3, 7p15.2, 8q24.21, 10q11.23, 10q26.13, 11p15.5, 11q13.2, 11q13.3. Statistically significant associations were replicated for other six SNPs only with a particular disease phenotype: low‐grade tumour and low PSA levels (rs1512268), high PSA levels (rs401681 and rs11649743), less aggressive cancers (rs1465618, rs721048, rs17021918). The strongest association of our tested SNP's with PSA in controls was for rs2735839, with 29% increase for each copy of the major allele G, consistent with previous results. Our results suggest that rs4962416, previously associated only with prostate cancer, is also associated with PSA levels, with 12% increase for each copy of the minor allele C. The study enabled the replication of the effect for the majority of previously reported genetic variants in a set of clinically relevant prostate cancers. This is the first replication study on these loci, known to associate with prostate cancer, in a Romanian population. 相似文献
1000.
汉族人群NOS3 A-922G、NOS3 T-786C 与NOS3 G894T SNP的等位基因及其组合分布与高血压的相关性 总被引:5,自引:0,他引:5
为了分析汉族人群一氧化氮合酶基因NOS3 A-922G、NOS3 T-786C 与NOS3 G894T单核苷酸多态性(single nucleotide polymorphism,SNP)的等位基因及其组合分布与高血压病的相关性,选取无亲缘关系的高血压病人192例(男97例,女95例)以及无亲缘关系的健康个体122例(男76例,女46例)为对照组,提取静脉血白细胞基因组DNA,采用等位基因特异性引物PCR技术检测NOS3 A-922G、NOS3 T-786C 与NOS3 G894T 3个位点的基因型。其结果显示:高血压病组与对照组NOS3 G894T、NOS3A-922G及NOS3 T-786C各等位基因型及其基因单倍型频率比较无显著性差异(P>0.05)。男、女性别分层研究:无论男亚组还是女亚组均未发现NOS3 A-922G、NOS3 T-786C 与NOS3 G894T各个位点SNP与高血压病有相关性。等位基因组合分布研究发现NOS3 G894G +A-922G+T-786T组合基因型总体频率分布在高血压病组与正常对照组之间有显著性差异(P<0.05,χ2= 4.5944)。男、女性别分层研究:男亚组上述3个位点SNP的各个组合基因型分布频率在高血压病组与正常对照组之间无显著性差异(P>0.05);女亚组中携带NOS3 G894G+A-922G+T-786C 的组合基因型分布频率在高血压病组与正常对照组之间有显著性差异(P<0.01,χ2=8.502)。研究发现,在中国汉族人群中NOS3A–922 G、NOS3 T-786C 与NOS3 G894T SNP与高血压病无明确的相关性,且无性别差异。组合分布研究发现,NOS3 G894G+A-922G+T-786C 的组合基因型分布频率在高血压病女性亚组较健康女性亚组明显减低,提示携带该组合基因型女性人群可能不易患高血压病。 相似文献