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971.
B. Persson J. Hedlund H. Jörnvall 《Cellular and molecular life sciences : CMLS》2008,65(24):3879-3894
The MDR superfamily with ~350-residue subunits contains the classical liver alcohol dehydrogenase (ADH), quinone reductase,
leukotriene B4 dehydrogenase and many more forms. ADH is a dimeric zinc metalloprotein and occurs as five different classes
in humans, resulting from gene duplications during vertebrate evolution, the first one traced to ~500 MYA (million years ago)
from an ancestral formaldehyde dehydrogenase line. Like many duplications at that time, it correlates with enzymogenesis of
new activities, contributing to conditions for emergence of vertebrate land life from osseous fish. The speed of changes correlates
with function, as do differential evolutionary patterns in separate segments. Subsequent recognitions now define at least
40 human MDR members in the Uniprot database (corresponding to 25 genes when excluding close homologues), and in all species
at least 10888 entries. Overall, variability is large, but like for many dehydrogenases, subdivided into constant and variable
forms, corresponding to household and emerging enzyme activities, respectively. This review covers basic facts and describes
eight large MDR families and nine smaller families. Combined, they have specific substrates in metabolic pathways, some with
wide substrate specificity, and several with little known functions. 相似文献
972.
Pasternack SM von Kügelgen I Al Aboud K Lee YA Rüschendorf F Voss K Hillmer AM Molderings GJ Franz T Ramirez A Nürnberg P Nöthen MM Betz RC 《Nature genetics》2008,40(3):329-334
Hypotrichosis simplex is a group of nonsyndromic human alopecias. We mapped an autosomal recessive form of this disorder to chromosome 13q14.11-13q21.33, and identified homozygous truncating mutations in P2RY5, which encodes an orphan G protein-coupled receptor. Furthermore, we identified oleoyl-L-alpha-lysophosphatidic acid (LPA), a bioactive lipid, as a ligand for P2Y5 in reporter gene and radioligand binding experiments. Homology and studies of signaling transduction pathways suggest that P2Y5 is a member of a subgroup of LPA receptors, which also includes LPA4 and LPA5. Our study is the first to implicate a G protein-coupled receptor as essential for and specific to the maintenance of human hair growth. This finding may provide opportunities for new therapeutic approaches to the treatment of hair loss in humans. 相似文献
973.
Benzinou M Creemers JW Choquet H Lobbens S Dina C Durand E Guerardel A Boutin P Jouret B Heude B Balkau B Tichet J Marre M Potoczna N Horber F Le Stunff C Czernichow S Sandbaek A Lauritzen T Borch-Johnsen K Andersen G Kiess W Körner A Kovacs P Jacobson P Carlsson LM Walley AJ Jørgensen T Hansen T Pedersen O Meyre D Froguel P 《Nature genetics》2008,40(8):943-945
Mutations in PCSK1 cause monogenic obesity. To assess the contribution of PCSK1 to polygenic obesity risk, we genotyped tag SNPs in a total of 13,659 individuals of European ancestry from eight independent case-control or family-based cohorts. The nonsynonymous variants rs6232, encoding N221D, and rs6234-rs6235, encoding the Q665E-S690T pair, were consistently associated with obesity in adults and children (P = 7.27 x 10(-8) and P = 2.31 x 10(-12), respectively). Functional analysis showed a significant impairment of the N221D-mutant PC1/3 protein catalytic activity. 相似文献
974.
Sulem P Gudbjartsson DF Stacey SN Helgason A Rafnar T Jakobsdottir M Steinberg S Gudjonsson SA Palsson A Thorleifsson G Pálsson S Sigurgeirsson B Thorisdottir K Ragnarsson R Benediktsdottir KR Aben KK Vermeulen SH Goldstein AM Tucker MA Kiemeney LA Olafsson JH Gulcher J Kong A Thorsteinsdottir U Stefansson K 《Nature genetics》2008,40(7):835-837
We present results from a genome-wide association study for variants associated with human pigmentation characteristics among 5,130 Icelanders, with follow-up analyses in 2,116 Icelanders and 1,214 Dutch individuals. Two coding variants in TPCN2 are associated with hair color, and a variant at the ASIP locus shows strong association with skin sensitivity to sun, freckling and red hair, phenotypic characteristics similar to those affected by well-known mutations in MC1R. 相似文献
975.
976.
Müller T Hess MW Schiefermeier N Pfaller K Ebner HL Heinz-Erian P Ponstingl H Partsch J Röllinghoff B Köhler H Berger T Lenhartz H Schlenck B Houwen RJ Taylor CJ Zoller H Lechner S Goulet O Utermann G Ruemmele FM Huber LA Janecke AR 《Nature genetics》2008,40(10):1163-1165
Following homozygosity mapping in a single kindred, we identified nonsense and missense mutations in MYO5B, encoding type Vb myosin motor protein, in individuals with microvillus inclusion disease (MVID). MVID is characterized by lack of microvilli on the surface of enterocytes and occurrence of intracellular vacuolar structures containing microvilli. In addition, mislocalization of transferrin receptor in MVID enterocytes suggests that MYO5B deficiency causes defective trafficking of apical and basolateral proteins in MVID. 相似文献
977.
Deficiency of PORCN, a regulator of Wnt signaling, is associated with focal dermal hypoplasia 总被引:1,自引:0,他引:1
Grzeschik KH Bornholdt D Oeffner F König A del Carmen Boente M Enders H Fritz B Hertl M Grasshoff U Höfling K Oji V Paradisi M Schuchardt C Szalai Z Tadini G Traupe H Happle R 《Nature genetics》2007,39(7):833-835
Focal dermal hypoplasia (FDH) is an X-linked dominant multisystem birth defect affecting tissues of ectodermal and mesodermal origin. Using a stepwise approach of (i) genetic mapping of FDH, (ii) high-resolution comparative genome hybridization to seek deletions in candidate chromosome areas and (iii) point mutation analysis in candidate genes, we identified PORCN, encoding a putative O-acyltransferase and potentially crucial for cellular export of Wnt signaling proteins, as the gene mutated in FDH. The findings implicate FDH as a developmental disorder caused by a deficiency in PORCN. 相似文献
978.
979.
Sulem P Gudbjartsson DF Stacey SN Helgason A Rafnar T Magnusson KP Manolescu A Karason A Palsson A Thorleifsson G Jakobsdottir M Steinberg S Pálsson S Jonasson F Sigurgeirsson B Thorisdottir K Ragnarsson R Benediktsdottir KR Aben KK Kiemeney LA Olafsson JH Gulcher J Kong A Thorsteinsdottir U Stefansson K 《Nature genetics》2007,39(12):1443-1452
Hair, skin and eye colors are highly heritable and visible traits in humans. We carried out a genome-wide association scan for variants associated with hair and eye pigmentation, skin sensitivity to sun and freckling among 2,986 Icelanders. We then tested the most closely associated SNPs from six regions--four not previously implicated in the normal variation of human pigmentation--and replicated their association in a second sample of 2,718 Icelanders and a sample of 1,214 Dutch. The SNPs from all six regions met the criteria for genome-wide significance. A variant in SLC24A4 is associated with eye and hair color, a variant near KITLG is associated with hair color, two coding variants in TYR are associated with eye color and freckles, and a variant on 6p25.3 is associated with freckles. The fifth region provided refinements to a previously reported association in OCA2, and the sixth encompasses previously described variants in MC1R. 相似文献
980.
Variation in interleukin 7 receptor alpha chain (IL7R) influences risk of multiple sclerosis 总被引:12,自引:0,他引:12
Lundmark F Duvefelt K Iacobaeus E Kockum I Wallström E Khademi M Oturai A Ryder LP Saarela J Harbo HF Celius EG Salter H Olsson T Hillert J 《Nature genetics》2007,39(9):1108-1113
Multiple sclerosis is a chronic, often disabling, disease of the central nervous system affecting more than 1 in 1,000 people in most western countries. The inflammatory lesions typical of multiple sclerosis show autoimmune features and depend partly on genetic factors. Of these genetic factors, only the HLA gene complex has been repeatedly confirmed to be associated with multiple sclerosis, despite considerable efforts. Polymorphisms in a number of non-HLA genes have been reported to be associated with multiple sclerosis, but so far confirmation has been difficult. Here, we report compelling evidence that polymorphisms in IL7R, which encodes the interleukin 7 receptor alpha chain (IL7Ralpha), indeed contribute to the non-HLA genetic risk in multiple sclerosis, demonstrating a role for this pathway in the pathophysiology of this disease. In addition, we report altered expression of the genes encoding IL7Ralpha and its ligand, IL7, in the cerebrospinal fluid compartment of individuals with multiple sclerosis. 相似文献