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71.
刘忠 张玉虎 马英君 Y.Sasaki K.Yamada H.Oshima H.Yokose M.Ishizuka T.Komatsubara K.Furuno 《中国科学(G辑)》2003,33(1):27-33
利用在束γ谱学方法, 通过124Sn (7Li, α2n)反应研究了125Sb的激发态, 首次建立了125Sb的高自旋能级纲图, 其中包括21条新 γ 跃迁和14个新能级. 发现1970, 2110和2470 keV 3个能级为同质异能态, 基于延迟符合测量确定了它们的寿命范围, 并确定其自旋、宇称分别为15/2-, 19/2-和23/2+. 根据粒子-核芯耦合图像和经验壳模型计算解释了125Sb的能级结构, 3个同质异能态的组态分别被指定为πg7/2 Äv(h11/2s1/2)5- , πg7/2 Ä v(h11/2d3/2)7-, 和πg7/2 Äv(h211/2)10+ 相似文献
72.
Meta-analysis identifies nine new loci associated with rheumatoid arthritis in the Japanese population 总被引:1,自引:0,他引:1
Okada Y Terao C Ikari K Kochi Y Ohmura K Suzuki A Kawaguchi T Stahl EA Kurreeman FA Nishida N Ohmiya H Myouzen K Takahashi M Sawada T Nishioka Y Yukioka M Matsubara T Wakitani S Teshima R Tohma S Takasugi K Shimada K Murasawa A Honjo S Matsuo K Tanaka H Tajima K Suzuki T Iwamoto T Kawamura Y Tanii H Okazaki Y Sasaki T Gregersen PK Padyukov L Worthington J Siminovitch KA Lathrop M Taniguchi A Takahashi A Tokunaga K Kubo M Nakamura Y Kamatani N Mimori T Plenge RM Yamanaka H Momohara S Yamada R 《Nature genetics》2012,44(5):511-516
Rheumatoid arthritis is a common autoimmune disease characterized by chronic inflammation. We report a meta-analysis of genome-wide association studies (GWAS) in a Japanese population including 4,074 individuals with rheumatoid arthritis (cases) and 16,891 controls, followed by a replication in 5,277 rheumatoid arthritis cases and 21,684 controls. Our study identified nine loci newly associated with rheumatoid arthritis at a threshold of P < 5.0 × 10(-8), including B3GNT2, ANXA3, CSF2, CD83, NFKBIE, ARID5B, PDE2A-ARAP1, PLD4 and PTPN2. ANXA3 was also associated with susceptibility to systemic lupus erythematosus (P = 0.0040), and B3GNT2 and ARID5B were associated with Graves' disease (P = 3.5 × 10(-4) and 2.9 × 10(-4), respectively). We conducted a multi-ancestry comparative analysis with a previous meta-analysis in individuals of European descent (5,539 rheumatoid arthritis cases and 20,169 controls). This provided evidence of shared genetic risks of rheumatoid arthritis between the populations. 相似文献
73.
74.
Perceptual learning without perception. 总被引:7,自引:0,他引:7
The brain is able to adapt rapidly and continually to the surrounding environment, becoming increasingly sensitive to important and frequently encountered stimuli. It is often claimed that this adaptive learning is highly task-specific, that is, we become more sensitive to the critical signals in the tasks we attend to. Here, we show a new type of perceptual learning, which occurs without attention, without awareness and without any task relevance. Subjects were repeatedly presented with a background motion signal so weak that its direction was not visible; the invisible motion was an irrelevant background to the central task that engaged the subject's attention. Despite being below the threshold of visibility and being irrelevant to the central task, the repetitive exposure improved performance specifically for the direction of the exposed motion when tested in a subsequent suprathreshold test. These results suggest that a frequently presented feature sensitizes the visual system merely owing to its frequency, not its relevance or salience. 相似文献
75.
76.
Thomas RK Baker AC Debiasi RM Winckler W Laframboise T Lin WM Wang M Feng W Zander T MacConaill L Macconnaill LE Lee JC Nicoletti R Hatton C Goyette M Girard L Majmudar K Ziaugra L Wong KK Gabriel S Beroukhim R Peyton M Barretina J Dutt A Emery C Greulich H Shah K Sasaki H Gazdar A Minna J Armstrong SA Mellinghoff IK Hodi FS Dranoff G Mischel PS Cloughesy TF Nelson SF Liau LM Mertz K Rubin MA Moch H Loda M Catalona W Fletcher J Signoretti S Kaye F Anderson KC Demetri GD Dummer R Wagner S 《Nature genetics》2007,39(3):347-351
Systematic efforts are underway to decipher the genetic changes associated with tumor initiation and progression. However, widespread clinical application of this information is hampered by an inability to identify critical genetic events across the spectrum of human tumors with adequate sensitivity and scalability. Here, we have adapted high-throughput genotyping to query 238 known oncogene mutations across 1,000 human tumor samples. This approach established robust mutation distributions spanning 17 cancer types. Of 17 oncogenes analyzed, we found 14 to be mutated at least once, and 298 (30%) samples carried at least one mutation. Moreover, we identified previously unrecognized oncogene mutations in several tumor types and observed an unexpectedly high number of co-occurring mutations. These results offer a new dimension in tumor genetics, where mutations involving multiple cancer genes may be interrogated simultaneously and in 'real time' to guide cancer classification and rational therapeutic intervention. 相似文献
77.
X-ray analysis of the pancreatic hormone glucagon shows that in crystals the polypeptide adopts a mainly helical conformation, which is stabilised by hydrophobic interactions between molecules related by threefold symmetry. A model is presented in which the glucagon molecule exists in dilute solutions as an equilibrium population of conformers with little retention of conformers with little retention of structure, and in which the helical conformation is stablised by hydrophobic interactions either as an oligomer or as a complex with the receptor. 相似文献
78.
79.
Imprinted genes are epigenetically marked during gametogenesis so that they are exclusively expressed from either the paternal or the maternal allele in offspring. Imprinting prevents parthenogenesis in mammals and is often disrupted in congenital malformation syndromes, tumours and cloned animals. Although de novo DNA methyltransferases of the Dnmt3 family are implicated in maternal imprinting, the lethality of Dnmt3a and Dnmt3b knockout mice has precluded further studies. We here report the disruption of Dnmt3a and Dnmt3b in germ cells, with their preservation in somatic cells, by conditional knockout technology. Offspring from Dnmt3a conditional mutant females die in utero and lack methylation and allele-specific expression at all maternally imprinted loci examined. Dnmt3a conditional mutant males show impaired spermatogenesis and lack methylation at two of three paternally imprinted loci examined in spermatogonia. By contrast, Dnmt3b conditional mutants and their offspring show no apparent phenotype. The phenotype of Dnmt3a conditional mutants is indistinguishable from that of Dnmt3L knockout mice, except for the discrepancy in methylation at one locus. These results indicate that both Dnmt3a and Dnmt3L are required for methylation of most imprinted loci in germ cells, but also suggest the involvement of other factors. 相似文献
80.