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排序方式: 共有242条查询结果,搜索用时 15 毫秒
91.
The genomic and transcriptomic architecture of 2,000 breast tumours reveals novel subgroups 总被引:1,自引:0,他引:1
Curtis C Shah SP Chin SF Turashvili G Rueda OM Dunning MJ Speed D Lynch AG Samarajiwa S Yuan Y Gräf S Ha G Haffari G Bashashati A Russell R McKinney S;METABRIC Group Langerød A Green A Provenzano E Wishart G Pinder S Watson P Markowetz F Murphy L Ellis I Purushotham A Børresen-Dale AL Brenton JD Tavaré S Caldas C Aparicio S 《Nature》2012,486(7403):346-352
92.
Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment 总被引:2,自引:0,他引:2
Scherber C Eisenhauer N Weisser WW Schmid B Voigt W Fischer M Schulze ED Roscher C Weigelt A Allan E Bessler H Bonkowski M Buchmann N Buscot F Clement LW Ebeling A Engels C Halle S Kertscher I Klein AM Koller R König S Kowalski E Kummer V Kuu A Lange M Lauterbach D Middelhoff C Migunova VD Milcu A Müller R Partsch S Petermann JS Renker C Rottstock T Sabais A Scheu S Schumacher J Temperton VM Tscharntke T 《Nature》2010,468(7323):553-556
Biodiversity is rapidly declining, and this may negatively affect ecosystem processes, including economically important ecosystem services. Previous studies have shown that biodiversity has positive effects on organisms and processes across trophic levels. However, only a few studies have so far incorporated an explicit food-web perspective. In an eight-year biodiversity experiment, we studied an unprecedented range of above- and below-ground organisms and multitrophic interactions. A multitrophic data set originating from a single long-term experiment allows mechanistic insights that would not be gained from meta-analysis of different experiments. Here we show that plant diversity effects dampen with increasing trophic level and degree of omnivory. This was true both for abundance and species richness of organisms. Furthermore, we present comprehensive above-ground/below-ground biodiversity food webs. Both above ground and below ground, herbivores responded more strongly to changes in plant diversity than did carnivores or omnivores. Density and richness of carnivorous taxa was independent of vegetation structure. Below-ground responses to plant diversity were consistently weaker than above-ground responses. Responses to increasing plant diversity were generally positive, but were negative for biological invasion, pathogen infestation and hyperparasitism. Our results suggest that plant diversity has strong bottom-up effects on multitrophic interaction networks, with particularly strong effects on lower trophic levels. Effects on higher trophic levels are indirectly mediated through bottom-up trophic cascades. 相似文献
93.
Alexandr V. Bazhin Vojtech Tambor Boyan Dikov Pavel P. Philippov Dirk Schadendorf Stefan B. Eichmüller 《Cellular and molecular life sciences : CMLS》2010,67(5):817-828
Malignant melanoma is one of the most aggressive human neoplasms which develop from the malignant transformation of normal
epithelial melanocytes and share the lineage with retinal cells. cGMP-phosphodiesterase 6 (PDE6) is one of the cancer-retina
antigens newly identified in melanoma cells. Normally, PDE6 hydrolyzes the photoreceptor second messenger cGMP allowing the
visual signal transduction in photoreceptor cells. cGMP also play an important signaling role in stimulating melanogenesis
in human melanocytes. Here, we present evidence that PDE6 is a key enzyme regulating the cGMP metabolism in melanoma cells.
Decrease in intracellular cGMP leads to calcium accumulation in melanoma cells. In these cells, cGMP-phosphodiesterase 6 can
be activated by another cancer-retina antigen, transducin, through Wnt5a–Frizzled-2 cascade, which leads to a lowering of
cGMP and an increase in intracellular calcium mobilization. Thus, the aberrant expression of PDE6 may control cGMP metabolism
and calcium homeostasis in melanoma cells. 相似文献
94.
Tommy Baumann Urs Kämpfer Stefan Schürch Johann Schaller Carlo Largiadèr Wolfgang Nentwig Lucia Kuhn-Nentwig 《Cellular and molecular life sciences : CMLS》2010,67(16):2787-2798
Three novel glycine-rich peptides, named ctenidin 1–3, with activity against the Gram-negative bacterium E. coli, were isolated and characterized from hemocytes of the spider Cupiennius salei. Ctenidins have a high glycine content (>70%), similarly to other glycine-rich peptides, the acanthoscurrins, from another spider, Acanthoscurria gomesiana. A combination of mass spectrometry, Edman degradation, and cDNA cloning revealed the presence of three isoforms of ctenidin, at least two of them originating from simple, intronless genes. The full-length sequences of the ctenidins consist of a 19 amino acid residues signal peptide followed by the mature peptides of 109, 119, or 120 amino acid residues. The mature peptides are post-translationally modified by the cleavage of one or two C-terminal cationic amino acid residue(s) and amidation of the newly created mature C-terminus. Tissue expression analysis revealed that ctenidins are constitutively expressed in hemocytes and to a small extent also in the subesophageal nerve mass. 相似文献
95.
Speliotes EK Willer CJ Berndt SI Monda KL Thorleifsson G Jackson AU Lango Allen H Lindgren CM Luan J Mägi R Randall JC Vedantam S Winkler TW Qi L Workalemahu T Heid IM Steinthorsdottir V Stringham HM Weedon MN Wheeler E Wood AR Ferreira T Weyant RJ Segrè AV Estrada K Liang L Nemesh J Park JH Gustafsson S Kilpeläinen TO Yang J Bouatia-Naji N Esko T Feitosa MF Kutalik Z Mangino M Raychaudhuri S Scherag A Smith AV Welch R Zhao JH Aben KK Absher DM Amin N Dixon AL Fisher E Glazer NL Goddard ME 《Nature genetics》2010,42(11):937-948
Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ~ 2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10??), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation. 相似文献
96.
Ellinghaus E Ellinghaus D Stuart PE Nair RP Debrus S Raelson JV Belouchi M Fournier H Reinhard C Ding J Li Y Tejasvi T Gudjonsson J Stoll SW Voorhees JJ Lambert S Weidinger S Eberlein B Kunz M Rahman P Gladman DD Gieger C Wichmann HE Karlsen TH Mayr G Albrecht M Kabelitz D Mrowietz U Abecasis GR Elder JT Schreiber S Weichenthal M Franke A 《Nature genetics》2010,42(11):991-995
97.
98.
Müller M Mazur AJ Behrmann E Diensthuber RP Radke MB Qu Z Littwitz C Raunser S Schoenenberger CA Manstein DJ Mannherz HG 《Cellular and molecular life sciences : CMLS》2012,69(20):3457-3479
Inherited cardiomyopathies are caused by point mutations in sarcomeric gene products, including α-cardiac muscle actin (ACTC1). We examined the biochemical and cell biological properties of the α-cardiac actin mutations Y166C and M305L identified in hypertrophic cardiomyopathy (HCM). Untagged wild-type (WT) cardiac actin, and the Y166C and M305L mutants were expressed by the baculovirus/Sf9-cell system and affinity purified by immobilized gelsolin G4-6. Their correct folding was verified by a number of assays. The mutant actins also displayed a disturbed intrinsic ATPase activity and an altered polymerization behavior in the presence of tropomyosin, gelsolin, and Arp2/3 complex. Both mutants stimulated the cardiac β-myosin ATPase to only 50?% of WT cardiac F-actin. Copolymers of WT and increasing amounts of the mutant actins led to a reduced stimulation of the myosin ATPase. Transfection of established cell lines revealed incorporation of EGFP- and hemagglutinin (HA)-tagged WT and both mutant actins into cytoplasmic stress fibers. Adenoviral vectors of HA-tagged WT and Y166C actin were successfully used to infect adult and neonatal rat cardiomyocytes (NRCs). The expressed HA-tagged actins were incorporated into the minus-ends of NRC thin filaments, demonstrating the ability to form hybrid thin filaments with endogenous actin. In NRCs, the Y166C mutant led after 72?h to a shortening of the sarcomere length when compared to NRCs infected with WT actin. Thus our data demonstrate that a mutant actin can be integrated into cardiomyocyte thin filaments and by its reduced mode of myosin interaction might be the basis for the initiation of HCM. 相似文献
99.
Comas I Borrell S Roetzer A Rose G Malla B Kato-Maeda M Galagan J Niemann S Gagneux S 《Nature genetics》2012,44(1):106-110
Epidemics of drug-resistant bacteria emerge worldwide, even as resistant strains frequently have reduced fitness compared to their drug-susceptible counterparts. Data from model systems suggest that the fitness cost of antimicrobial resistance can be reduced by compensatory mutations; however, there is limited evidence that compensatory evolution has any significant role in the success of drug-resistant bacteria in human populations. Here we describe a set of compensatory mutations in the RNA polymerase genes of rifampicin-resistant M. tuberculosis, the etiologic agent of human tuberculosis (TB). M. tuberculosis strains harboring these compensatory mutations showed a high competitive fitness in vitro. Moreover, these mutations were associated with high fitness in vivo, as determined by examining their relative clinical frequency across patient populations. Of note, in countries with the world's highest incidence of multidrug-resistant (MDR) TB, more than 30% of MDR clinical isolates had this form of mutation. Our findings support a role for compensatory evolution in the global epidemics of MDR TB. 相似文献
100.
Holm H Gudbjartsson DF Sulem P Masson G Helgadottir HT Zanon C Magnusson OT Helgason A Saemundsdottir J Gylfason A Stefansdottir H Gretarsdottir S Matthiasson SE Thorgeirsson GM Jonasdottir A Sigurdsson A Stefansson H Werge T Rafnar T Kiemeney LA Parvez B Muhammad R Roden DM Darbar D Thorleifsson G Walters GB Kong A Thorsteinsdottir U Arnar DO Stefansson K 《Nature genetics》2011,43(4):316-320
Through complementary application of SNP genotyping, whole-genome sequencing and imputation in 38,384 Icelanders, we have discovered a previously unidentified sick sinus syndrome susceptibility gene, MYH6, encoding the alpha heavy chain subunit of cardiac myosin. A missense variant in this gene, c.2161C>T, results in the conceptual amino acid substitution p.Arg721Trp, has an allelic frequency of 0.38% in Icelanders and associates with sick sinus syndrome with an odds ratio = 12.53 and P = 1.5 × 10?2?. We show that the lifetime risk of being diagnosed with sick sinus syndrome is around 6% for non-carriers of c.2161C>T but is approximately 50% for carriers of the c.2161C>T variant. 相似文献