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排序方式: 共有105条查询结果,搜索用时 0 毫秒
91.
A PGC1-α-dependent myokine that drives brown-fat-like development of white fat and thermogenesis 总被引:1,自引:0,他引:1
Boström P Wu J Jedrychowski MP Korde A Ye L Lo JC Rasbach KA Boström EA Choi JH Long JZ Kajimura S Zingaretti MC Vind BF Tu H Cinti S Højlund K Gygi SP Spiegelman BM 《Nature》2012,481(7382):463-468
92.
Gontan C Achame EM Demmers J Barakat TS Rentmeester E van IJcken W Grootegoed JA Gribnau J 《Nature》2012,485(7398):386-390
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96.
Genetics: junk DNA as an evolutionary force 总被引:2,自引:0,他引:2
97.
Parallel evolution of similar traits in independent populations that inhabit ecologically similar environments strongly implicates natural selection as the cause of evolution. Parallel speciation is a special form of parallel evolution where traits that determine reproductive isolation evolve repeatedly, in closely related populations, as by-products of adaptation to ecological conditions. The outcome of such parallel evolution is that ecologically divergent pairs of populations exhibit greater levels of reproductive isolation than ecologically similar pairs of populations of a similar or younger age. The parallel evolution of reproductive isolation provides strong evidence for natural selection in the process of speciation, but only one conclusive example from nature is known. Populations of the walking-stick insect Timema cristinae that use different host-plant species have diverged in body size and shape, host preference, behaviour and the relative frequency of two highly cryptic colour-pattern morphs. Here we report that divergent selection for host adaptation, and not genetic drift, has promoted the parallel evolution of sexual isolation in this species. Our findings represent a clear demonstration that host-plant adaptation can play a crucial and repeatable role in the early stages of speciation. 相似文献
98.
FACL4, encoding fatty acid-CoA ligase 4, is mutated in nonspecific X-linked mental retardation 总被引:1,自引:0,他引:1
Meloni I Muscettola M Raynaud M Longo I Bruttini M Moizard MP Gomot M Chelly J des Portes V Fryns JP Ropers HH Magi B Bellan C Volpi N Yntema HG Lewis SE Schaffer JE Renieri A 《Nature genetics》2002,30(4):436-440
X-linked mental retardation (XLMR) is an inherited condition that causes failure to develop cognitive abilities, owing to mutations in a gene on the X chromosome. The latest XLMR update lists up to 136 conditions leading to 'syndromic', or 'specific', mental retardation (MRXS) and 66 entries leading to 'nonspecific' mental retardation (MRX). For 9 of the 66 MRX entries, the causative gene has been identified. Our recent discovery of the contiguous gene deletion syndrome ATS-MR (previously known as Alport syndrome, mental retardation, midface hypoplasia, elliptocytosis, OMIM #300194), characterized by Alport syndrome (ATS) and mental retardation (MR), indicated Xq22.3 as a region containing one mental retardation gene. Comparing the extent of deletion between individuals with ATS-MR and individuals with ATS alone allowed us to define a critical region for mental retardation of approximately 380 kb, containing four genes. Here we report the identification of two point mutations, one missense and one splice-site change, in the gene FACL4 in two families with nonspecific mental retardation. Analysis of enzymatic activity in lymphoblastoid cell lines from affected individuals of both families revealed low levels compared with normal cells, indicating that both mutations are null mutations. All carrier females with either point mutations or genomic deletions in FACL4 showed a completely skewed X-inactivation, suggesting that the gene influences survival advantage. FACL4 is the first gene shown to be involved in nonspecific mental retardation and fatty-acid metabolism. 相似文献
99.
Human chromosome 21 gene expression atlas in the mouse 总被引:19,自引:0,他引:19
Reymond A Marigo V Yaylaoglu MB Leoni A Ucla C Scamuffa N Caccioppoli C Dermitzakis ET Lyle R Banfi S Eichele G Antonarakis SE Ballabio A 《Nature》2002,420(6915):582-586
100.
Ueda H Howson JM Esposito L Heward J Snook H Chamberlain G Rainbow DB Hunter KM Smith AN Di Genova G Herr MH Dahlman I Payne F Smyth D Lowe C Twells RC Howlett S Healy B Nutland S Rance HE Everett V Smink LJ Lam AC Cordell HJ Walker NM Bordin C Hulme J Motzo C Cucca F Hess JF Metzker ML Rogers J Gregory S Allahabadia A Nithiyananthan R Tuomilehto-Wolf E Tuomilehto J Bingley P Gillespie KM Undlien DE Rønningen KS Guja C Ionescu-Tîrgovişte C Savage DA Maxwell AP Carson DJ Patterson CC Franklyn JA 《Nature》2003,423(6939):506-511
Genes and mechanisms involved in common complex diseases, such as the autoimmune disorders that affect approximately 5% of the population, remain obscure. Here we identify polymorphisms of the cytotoxic T lymphocyte antigen 4 gene (CTLA4)--which encodes a vital negative regulatory molecule of the immune system--as candidates for primary determinants of risk of the common autoimmune disorders Graves' disease, autoimmune hypothyroidism and type 1 diabetes. In humans, disease susceptibility was mapped to a non-coding 6.1 kb 3' region of CTLA4, the common allelic variation of which was correlated with lower messenger RNA levels of the soluble alternative splice form of CTLA4. In the mouse model of type 1 diabetes, susceptibility was also associated with variation in CTLA-4 gene splicing with reduced production of a splice form encoding a molecule lacking the CD80/CD86 ligand-binding domain. Genetic mapping of variants conferring a small disease risk can identify pathways in complex disorders, as exemplified by our discovery of inherited, quantitative alterations of CTLA4 contributing to autoimmune tissue destruction. 相似文献