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排序方式: 共有4676条查询结果,搜索用时 438 毫秒
1.
新的、高密度树木种植正在给林业生物技术带来迅速的变化。但是如果不能克服生态风险和经济障碍.这些新的方法或许永远也无法使用—— 相似文献
2.
The Shwachman-Bodian-Diamond syndrome protein mediates translational activation of ribosomes in yeast 总被引:1,自引:0,他引:1
Menne TF Goyenechea B Sánchez-Puig N Wong CC Tonkin LM Ancliff PJ Brost RL Costanzo M Boone C Warren AJ 《Nature genetics》2007,39(4):486-495
The autosomal recessive disorder Shwachman-Diamond syndrome, characterized by bone marrow failure and leukemia predisposition, is caused by deficiency of the highly conserved Shwachman-Bodian-Diamond syndrome (SBDS) protein. Here, we identify the function of the yeast SBDS ortholog Sdo1, showing that it is critical for the release and recycling of the nucleolar shuttling factor Tif6 from pre-60S ribosomes, a key step in 60S maturation and translational activation of ribosomes. Using genome-wide synthetic genetic array mapping, we identified multiple TIF6 gain-of-function alleles that suppressed the pre-60S nuclear export defects and cytoplasmic mislocalization of Tif6 observed in sdo1Delta cells. Sdo1 appears to function within a pathway containing elongation factor-like 1, and together they control translational activation of ribosomes. Thus, our data link defective late 60S ribosomal subunit maturation to an inherited bone marrow failure syndrome associated with leukemia predisposition. 相似文献
3.
Houlden H Johnson J Gardner-Thorpe C Lashley T Hernandez D Worth P Singleton AB Hilton DA Holton J Revesz T Davis MB Giunti P Giunti P Wood NW 《Nature genetics》2007,39(12):1434-1436
The microtubule-associated protein tau (encoded by MAPT) and several tau kinases have been implicated in neurodegeneration, but only MAPT has a proven role in disease. We identified mutations in the gene encoding tau tubulin kinase 2 (TTBK2) as the cause of spinocerebellar ataxia type 11. Affected brain tissue showed substantial cerebellar degeneration and tau deposition. These data suggest that TTBK2 is important in the tau cascade and in spinocerebellar degeneration. 相似文献
4.
Tissue-specific and reversible RNA interference in transgenic mice 总被引:11,自引:0,他引:11
Dickins RA McJunkin K Hernando E Premsrirut PK Krizhanovsky V Burgess DJ Kim SY Cordon-Cardo C Zender L Hannon GJ Lowe SW 《Nature genetics》2007,39(7):914-921
Genetically engineered mice provide powerful tools for understanding mammalian gene function. These models traditionally rely on gene overexpression from transgenes or targeted, irreversible gene mutation. By adapting the tetracycline (tet)-responsive system previously used for gene overexpression, we have developed a simple transgenic system to reversibly control endogenous gene expression using RNA interference (RNAi) in mice. Transgenic mice harboring a tet-responsive RNA polymerase II promoter driving a microRNA-based short hairpin RNA targeting the tumor suppressor Trp53 reversibly express short hairpin RNA when crossed with existing mouse strains expressing general or tissue-specific 'tet-on' or 'tet-off' transactivators. Reversible Trp53 knockdown can be achieved in several tissues, and restoring Trp53 expression in lymphomas whose development is promoted by Trp53 knockdown leads to tumor regression. By leaving the target gene unaltered, this approach permits tissue-specific, reversible regulation of endogenous gene expression in vivo, with potential broad application in basic biology and drug target validation. 相似文献
5.
Recombination and linkage disequilibrium in Arabidopsis thaliana 总被引:4,自引:0,他引:4
Kim S Plagnol V Hu TT Toomajian C Clark RM Ossowski S Ecker JR Weigel D Nordborg M 《Nature genetics》2007,39(9):1151-1155
Linkage disequilibrium (LD) is a major aspect of the organization of genetic variation in natural populations. Here we describe the genome-wide pattern of LD in a sample of 19 Arabidopsis thaliana accessions using 341,602 non-singleton SNPs. LD decays within 10 kb on average, considerably faster than previously estimated. Tag SNP selection algorithms and 'hide-the-SNP' simulations suggest that genome-wide association mapping will require only 40%-50% of the observed SNPs, a reduction similar to estimates in a sample of African Americans. An Affymetrix genotyping array containing 250,000 SNPs has been designed based on these results; we demonstrate that it should have more than adequate coverage for genome-wide association mapping. The extent of LD is highly variable, and we find clear evidence of recombination hotspots, which seem to occur preferentially in intergenic regions. LD also reflects the action of selection, and it is more extensive between nonsynonymous polymorphisms than between synonymous polymorphisms. 相似文献
6.
St Onge RP Mani R Oh J Proctor M Fung E Davis RW Nislow C Roth FP Giaever G 《Nature genetics》2007,39(2):199-206
Systematic genetic interaction studies have illuminated many cellular processes. Here we quantitatively examine genetic interactions among 26 Saccharomyces cerevisiae genes conferring resistance to the DNA-damaging agent methyl methanesulfonate (MMS), as determined by chemogenomic fitness profiling of pooled deletion strains. We constructed 650 double-deletion strains, corresponding to all pairings of these 26 deletions. The fitness of single- and double-deletion strains were measured in the presence and absence of MMS. Genetic interactions were defined by combining principles from both statistical and classical genetics. The resulting network predicts that the Mph1 helicase has a role in resolving homologous recombination-derived DNA intermediates that is similar to (but distinct from) that of the Sgs1 helicase. Our results emphasize the utility of small molecules and multifactorial deletion mutants in uncovering functional relationships and pathway order. 相似文献
7.
A genome-wide association study for celiac disease identifies risk variants in the region harboring IL2 and IL21 总被引:14,自引:0,他引:14
van Heel DA Franke L Hunt KA Gwilliam R Zhernakova A Inouye M Wapenaar MC Barnardo MC Bethel G Holmes GK Feighery C Jewell D Kelleher D Kumar P Travis S Walters JR Sanders DS Howdle P Swift J Playford RJ McLaren WM Mearin ML Mulder CJ McManus R McGinnis R Cardon LR Deloukas P Wijmenga C 《Nature genetics》2007,39(7):827-829
We tested 310,605 SNPs for association in 778 individuals with celiac disease and 1,422 controls. Outside the HLA region, the most significant finding (rs13119723; P = 2.0 x 10(-7)) was in the KIAA1109-TENR-IL2-IL21 linkage disequilibrium block. We independently confirmed association in two further collections (strongest association at rs6822844, 24 kb 5' of IL21; meta-analysis P = 1.3 x 10(-14), odds ratio = 0.63), suggesting that genetic variation in this region predisposes to celiac disease. 相似文献
8.
The study of candidate genes over the past three decades has yielded notable successes in common-disease genetics. During
this time, however, interpretation of genetic association studies has been hampered by the use of clinical cohorts of inadequate
power and insufficient information on genetic variation in candidate genes. The unavailability of highthroughput and low-cost
genotyping technologies has also limited the scope of complex-disease genetic studies. More recently, however, the sequencing
and characterization of variation within the human genome has revolutionized genetic studies and enabled full genome-wide
scans for genes associated with disease. The identification of disease-associated (causative) genes has illuminated disease
mechanisms. The translation of this knowledge into direct clinical benefit in diagnosis, prognosis and therapy for an individual’s
disease still remains a challenge.
Received 11 September 2006; received after revision 17 December 2006; accepted 18 January 2007 相似文献
9.
Strell C Lang K Niggemann B Zaenker KS Entschladen F 《Cellular and molecular life sciences : CMLS》2007,64(24):3306-3316
The extravasation of leukocytes and tumor cells is a multi-step process with the involvement of various adhesion molecules
depending on the three steps rolling, adhesion, and diapedesis. We have developed an in vitro model, by which we investigated the rolling and adhesion of neutrophil granulocytes and MDA-MB-468 human breast carcinoma
cells to lung endothelial cells under physiological flow-conditions. We found that norepinephrine had an inhibitory function
on the fMLP-promoted adhesion of neutrophil granulocytes due to a down-regulation of β2-integrin. Furthermore, neutrophil
granulocytes serve as linking cells for the interaction of the MDA-MB-468 cells with the endothelium, which are both β2-integrin
negative, but express the β2-integrin ligand ICAM-1. In addition, we show here that N-cadherin is up-regulated on the endothelial
cells and on neutrophil granulocytes in response to fMLP. This up-regulation resulted in a significant increase of adherent
MDA-MB-468 cells, which are also N-cadherin positive.
Received 3 September 2007; received after revision 17 October 2007; accepted 22 October 2007 相似文献
10.