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排序方式: 共有394条查询结果,搜索用时 187 毫秒
91.
Prickett TD Wei X Cardenas-Navia I Teer JK Lin JC Walia V Gartner J Jiang J Cherukuri PF Molinolo A Davies MA Gershenwald JE Stemke-Hale K Rosenberg SA Margulies EH Samuels Y 《Nature genetics》2011,43(11):1119-1126
G protein-coupled receptors (GPCRs), the largest human gene family, are important regulators of signaling pathways. However, knowledge of their genetic alterations is limited. In this study, we used exon capture and massively parallel sequencing methods to analyze the mutational status of 734 GPCRs in melanoma. This investigation revealed that one family member, GRM3, was frequently mutated and that one of its mutations clustered within one position. Biochemical analysis of GRM3 alterations revealed that mutant GRM3 selectively regulated the phosphorylation of MEK, leading to increased anchorage-independent growth and migration. Melanoma cells expressing mutant GRM3 had reduced cell growth and cellular migration after short hairpin RNA-mediated knockdown of GRM3 or treatment with a selective MEK inhibitor, AZD-6244, which is currently being used in phase 2 clinical trials. Our study yields the most comprehensive map of genetic alterations in the GPCR gene family. 相似文献
92.
DNA polymerase γ (pol γ), encoded by POLG, is responsible for replicating human mitochondrial DNA. About 150 mutations in the human POLG have been identified in patients with mitochondrial diseases such as Alpers syndrome, progressive external ophthalmoplegia,
and ataxia-neuropathy syndromes. Because many of the mutations are described in single citations with no genotypic family
history, it is important to ascertain which mutations cause or contribute to mitochondrial disease. The vast majority of data
about POLG mutations has been generated from biochemical characterizations of recombinant pol γ. However, recently, the study of mitochondrial
dysfunction in Saccharomyces cerevisiae and mouse models provides important in vivo evidence for the role of POLG mutations in disease. Also, the published 3D-structure of the human pol γ assists in explaining some of the biochemical and
genetic properties of the mutants. This review summarizes the current evidence that identifies and explains disease-causing
POLG mutations. 相似文献
93.
Zhu P Liu J Bess J Chertova E Lifson JD Grisé H Ofek GA Taylor KA Roux KH 《Nature》2006,441(7095):847-852
Envelope glycoprotein (Env) spikes on AIDS retroviruses initiate infection of host cells and are therefore targets for vaccine development. Though crystal structures for partial Env subunits are known, the structure and distribution of native Env spikes on virions is obscure. We applied cryoelectron microscopy tomography to define ultrastructural details of spikes. Virions of wild-type human immunodeficiency virus 1 (HIV-1) and a mutant simian immunodeficiency virus (SIV) had approximately 14 and approximately 73 spikes per particle, respectively, with some clustering of HIV-1 spikes. Three-dimensional averaging showed that the surface glycoprotein (gp120) 'head' of each subunit of the trimeric SIV spike contains a primary mass, with two secondary lobes. The transmembrane glycoprotein 'stalk' of each trimer is composed of three independent legs that project obliquely from the trimer head, tripod-like. Reconciling available atomic structures with the three-dimensional whole spike density map yields insights into the orientation of Env spike structural elements and possible structural bases of their functions. 相似文献
94.
Long-range hydrophobic interactions operating underwater are important in the mediation of many natural and synthetic phenomena, such as protein folding, adhesion and colloid stability. Here we show that rough hydrophobic surfaces can experience attractive forces over distances more than 30 times greater than any reported previously, owing to the spontaneous evaporation of the intervening, confined water. Our finding highlights the importance of surface roughness in the interaction of extended structures in water, which has so far been largely overlooked. 相似文献
95.
Zhang J Grindley JC Yin T Jayasinghe S He XC Ross JT Haug JS Rupp D Porter-Westpfahl KS Wiedemann LM Wu H Li L 《Nature》2006,441(7092):518-522
Haematopoietic stem cells (HSCs) must achieve a balance between quiescence and activation that fulfils immediate demands for haematopoiesis without compromising long-term stem cell maintenance, yet little is known about the molecular events governing this balance. Phosphatase and tensin homologue (PTEN) functions as a negative regulator of the phosphatidylinositol-3-OH kinase (PI(3)K)-Akt pathway, which has crucial roles in cell proliferation, survival, differentiation and migration. Here we show that inactivation of PTEN in bone marrow HSCs causes their short-term expansion, but long-term decline, primarily owing to an enhanced level of HSC activation. PTEN-deficient HSCs engraft normally in recipient mice, but have an impaired ability to sustain haematopoietic reconstitution, reflecting the dysregulation of their cell cycle and decreased retention in the bone marrow niche. Mice with PTEN-mutant bone marrow also have an increased representation of myeloid and T-lymphoid lineages and develop myeloproliferative disorder (MPD). Notably, the cell populations that expand in PTEN mutants match those that become dominant in the acute myeloid/lymphoid leukaemia that develops in the later stages of MPD. Thus, PTEN has essential roles in restricting the activation of HSCs, in lineage fate determination, and in the prevention of leukaemogenesis. 相似文献
96.
Genetic determinants of ulcerative colitis include the ECM1 locus and five loci implicated in Crohn's disease 总被引:1,自引:0,他引:1
Fisher SA Tremelling M Anderson CA Gwilliam R Bumpstead S Prescott NJ Nimmo ER Massey D Berzuini C Johnson C Barrett JC Cummings FR Drummond H Lees CW Onnie CM Hanson CE Blaszczyk K Inouye M Ewels P Ravindrarajah R Keniry A Hunt S Carter M Watkins N Ouwehand W Lewis CM Cardon L;Wellcome Trust Case Control Consortium Lobo A Forbes A Sanderson J Jewell DP Mansfield JC Deloukas P Mathew CG Parkes M Satsangi J 《Nature genetics》2008,40(6):710-712
We report results of a nonsynonymous SNP scan for ulcerative colitis and identify a previously unknown susceptibility locus at ECM1. We also show that several risk loci are common to ulcerative colitis and Crohn's disease (IL23R, IL12B, HLA, NKX2-3 and MST1), whereas autophagy genes ATG16L1 and IRGM, along with NOD2 (also known as CARD15), are specific for Crohn's disease. These data provide the first detailed illustration of the genetic relationship between these common inflammatory bowel diseases. 相似文献
97.
Brown KM Macgregor S Montgomery GW Craig DW Zhao ZZ Iyadurai K Henders AK Homer N Campbell MJ Stark M Thomas S Schmid H Holland EA Gillanders EM Duffy DL Maskiell JA Jetann J Ferguson M Stephan DA Cust AE Whiteman D Green A Olsson H Puig S Ghiorzo P Hansson J Demenais F Goldstein AM Gruis NA Elder DE Bishop JN Kefford RF Giles GG Armstrong BK Aitken JF Hopper JL Martin NG Trent JM Mann GJ Hayward NK 《Nature genetics》2008,40(7):838-840
We conducted a genome-wide association pooling study for cutaneous melanoma and performed validation in samples totaling 2,019 cases and 2,105 controls. Using pooling, we identified a new melanoma risk locus on chromosome 20 (rs910873 and rs1885120), with replication in two further samples (combined P < 1 x 10(-15)). The per allele odds ratio was 1.75 (1.53, 2.01), with evidence for stronger association in early-onset cases. 相似文献
98.
Sun J Zheng SL Wiklund F Isaacs SD Purcell LD Gao Z Hsu FC Kim ST Liu W Zhu Y Stattin P Adami HO Wiley KE Dimitrov L Sun J Li T Turner AR Adams TS Adolfsson J Johansson JE Lowey J Trock BJ Partin AW Walsh PC Trent JM Duggan D Carpten J Chang BL Grönberg H Isaacs WB Xu J 《Nature genetics》2008,40(10):1153-1155
We carried out a fine-mapping study in the HNF1B gene at 17q12 in two study populations and identified a second locus associated with prostate cancer risk, approximately 26 kb centromeric to the first known locus (rs4430796); these loci are separated by a recombination hot spot. We confirmed the association with a SNP in the second locus (rs11649743) in five additional populations, with P = 1.7 x 10(-9) for an allelic test of the seven studies combined. The association at each SNP remained significant after adjustment for the other SNP. 相似文献
99.
Genome-wide association defines more than 30 distinct susceptibility loci for Crohn's disease 总被引:2,自引:0,他引:2
Barrett JC Hansoul S Nicolae DL Cho JH Duerr RH Rioux JD Brant SR Silverberg MS Taylor KD Barmada MM Bitton A Dassopoulos T Datta LW Green T Griffiths AM Kistner EO Murtha MT Regueiro MD Rotter JI Schumm LP Steinhart AH Targan SR Xavier RJ;NIDDK IBD Genetics Consortium Libioulle C Sandor C Lathrop M Belaiche J Dewit O Gut I Heath S Laukens D Mni M Rutgeerts P Van Gossum A Zelenika D Franchimont D Hugot JP de Vos M Vermeire S 《Nature genetics》2008,40(8):955-962
Several risk factors for Crohn's disease have been identified in recent genome-wide association studies. To advance gene discovery further, we combined data from three studies on Crohn's disease (a total of 3,230 cases and 4,829 controls) and carried out replication in 3,664 independent cases with a mixture of population-based and family-based controls. The results strongly confirm 11 previously reported loci and provide genome-wide significant evidence for 21 additional loci, including the regions containing STAT3, JAK2, ICOSLG, CDKAL1 and ITLN1. The expanded molecular understanding of the basis of this disease offers promise for informed therapeutic development. 相似文献
100.
Kopp JB Smith MW Nelson GW Johnson RC Freedman BI Bowden DW Oleksyk T McKenzie LM Kajiyama H Ahuja TS Berns JS Briggs W Cho ME Dart RA Kimmel PL Korbet SM Michel DM Mokrzycki MH Schelling JR Simon E Trachtman H Vlahov D Winkler CA 《Nature genetics》2008,40(10):1175-1184
The increased burden of chronic kidney and end-stage kidney diseases (ESKD) in populations of African ancestry has been largely unexplained. To identify genetic variants predisposing to idiopathic and HIV-1-associated focal segmental glomerulosclerosis (FSGS), we carried out an admixture-mapping linkage-disequilibrium genome scan on 190 African American individuals with FSGS and 222 controls. We identified a chromosome 22 region with a genome-wide logarithm of the odds (lod) score of 9.2 and a peak lod of 12.4 centered on MYH9, a functional candidate gene expressed in kidney podocytes. Multiple MYH9 SNPs and haplotypes were recessively associated with FSGS, most strongly a haplotype spanning exons 14 through 23 (OR = 5.0, 95% CI = 3.5-7.1; P = 4 x 10(-23), n = 852). This association extended to hypertensive ESKD (OR = 2.2, 95% CI = 1.5-3.4; n = 433), but not type 2 diabetic ESKD (n = 476). Genetic variation at the MYH9 locus substantially explains the increased burden of FSGS and hypertensive ESKD among African Americans. 相似文献