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排序方式: 共有346条查询结果,搜索用时 15 毫秒
91.
The public understanding of science 总被引:9,自引:0,他引:9
92.
Using Mn(OH)2 as precursor, LiOH as lithiating agent and (NH4)2S2O8 as oxidant, layeredo-LiMnO2 was obtained by a novel method—in situ oxidation-intercalation under mild conditions (80 °C). The product was characterized by XRD, ICP, TEM and7Li-NMR. The results reveal that orthorhombic LiMnO2 with high purity and good crystallinity can be obtained by this method. During electrochemical tests, a LiMnO2/Li cell shows an initial reversible capacity of 208 mAh · g−1 and a reversible capacity of 180 mAh · g−1 after 30 cycles at room temperature. 相似文献
93.
Treatment-specific changes in gene expression discriminate in vivo drug response in human leukemia cells 总被引:14,自引:0,他引:14
Cheok MH Yang W Pui CH Downing JR Cheng C Naeve CW Relling MV Evans WE 《Nature genetics》2003,34(1):85-90
To elucidate the genomics of cellular responses to cancer treatment, we analyzed the expression of over 9,600 human genes in acute lymphoblastic leukemia cells before and after in vivo treatment with methotrexate and mercaptopurine given alone or in combination. Based on changes in gene expression, we identified 124 genes that accurately discriminated among the four treatments. Discriminating genes included those involved in apoptosis, mismatch repair, cell cycle control and stress response. Only 14% of genes that changed when these medications were given as single agents also changed when they were given together. These data indicate that lymphoid leukemia cells of different molecular subtypes share common pathways of genomic response to the same treatment, that changes in gene expression are treatment-specific and that gene expression can illuminate differences in cellular response to drug combinations versus single agents. 相似文献
94.
Evolution of the MHC class I genes of a New World primate from ancestral homologues of human non-classical genes 总被引:7,自引:0,他引:7
The products of the classical human major histocompatibility complex (MHC) class I genes (HLA-A, -B, -C) are highly polymorphic molecules that bind peptides and present them to T lymphocytes. The non-polymorphic, non-classical MHC class I gene products (HLA-E, -F, -G) are not restricting elements for the majority of T lymphocytes. The evolutionary relationship of the non-classical and classical MHC class I genes is unclear. Here we present the cloning and sequencing of the MHC class I genes of a New World primate, the cotton-top tamarin (Saguinus oedipus). The expressed MHC class I genes of this species are more closely related to the human non-classical HLA-G gene than they are to genes of the human classical HLA-A, -B, and -C loci. These observations imply that classical and non-classical genes do not necessarily constitute mutually exclusive groups over evolutionary time. 相似文献
95.
Recent work suggests that an autosomal dominant gene for schizophrenia may be located on the 5q11-q13 region of chromosome 5 (refs 1 and 2): a report of schizophrenia associated with trisomy 5q11-q13 in two members of a family of Chinese origin prompted the discovery of linkage with markers p105-599Ha and p105-153Ra in five Icelandic and two English schizophrenic families. The strongest linkage was observed when the phenotype was broadly defined to include minor psychiatric diagnoses not traditionally considered part of the schizophrenia spectrum. By contrast, no evidence was found of linkage in a single multiplex Swedish schizophrenic pedigree. To determine whether these conflicting results arise from genetic and/or uncertainties in defining the schizophrenic phenotype, we examined fifteen Scottish schizophrenic families with restriction fragment length polymorphisms that span this region. We found no evidence for linkage, regardless of how broadly or narrowly the schizophrenic phenotype is defined, and conclude that a susceptibility locus, whose presence awaits confirmation, on the proximal portion of the long arm of chromosome 5 can be responsible for only a minority of cases of familial schizophrenia. 相似文献
96.
A. M. Rizk F. M. Hammouda S. E. Ismail M. M. El-Missiry F. J. Evans 《Cellular and molecular life sciences : CMLS》1984,40(8):808-809
Summary Two new aromatic derivatives of 5, 12-dihydroxy-6, 7-epoxy-resiniferonol were isolated from the leaves and twigs ofThymelea hirsuta L. (fam. Thymelaeaceae). These compounds were assigned the structures 12-O-cinnamoyl-5-hydroxy-6, 7-epoxyresiniferonol-9, 13, 14-ortho benzoate 1 and 12-O-heptadecenoyl-5-hydroxy-6, 7,-epoxy-resiniferonol-9, 13, 14-ortho benzoate 2. Both compounds induced erythema of mouse ears in a dose of 0.1 g per ear.Acknowledgments. S. Ismail and M. El-Missiry are grateful to the Royal Society for a travel and support grant. 相似文献
97.
We present here temporal and 0.2-2 MeV spectral data from two gamma bursts observed on 12 June and 16 August 1976, by detectors on the Solrad 11A and 11B satellites. The 12 June burst showed evidence for structure on time scales down to approximately 10 ms throughout its lifetime, whereas the 16 August burst varied only with characteristic times longer than a few tenths of a second. A search for both slow and fast spectral variability gave negative results. Accurate absolute burst times are, however, not yet available, but since both bursts were also observed by at least one Vela satellite, positions are calculable and will be reported. 相似文献
98.
Tomlinson IP Webb E Carvajal-Carmona L Broderick P Howarth K Pittman AM Spain S Lubbe S Walther A Sullivan K Jaeger E Fielding S Rowan A Vijayakrishnan J Domingo E Chandler I Kemp Z Qureshi M Farrington SM Tenesa A Prendergast JG Barnetson RA Penegar S Barclay E Wood W Martin L Gorman M Thomas H Peto J Bishop DT Gray R Maher ER Lucassen A Kerr D Evans DG;CORGI Consortium Schafmayer C Buch S Völzke H Hampe J Schreiber S John U Koessler T Pharoah P van Wezel T Morreau H Wijnen JT Hopper JL 《Nature genetics》2008,40(5):623-630
To identify colorectal cancer (CRC) susceptibility alleles, we conducted a genome-wide association study. In phase 1, we genotyped 550,163 tagSNPs in 940 familial colorectal tumor cases (627 CRC, 313 high-risk adenoma) and 965 controls. In phase 2, we genotyped 42,708 selected SNPs in 2,873 CRC cases and 2,871 controls. In phase 3, we evaluated 11 SNPs showing association at P < 10(-4) in a joint analysis of phases 1 and 2 in 4,287 CRC cases and 3,743 controls. Two SNPs were taken forward to phase 4 genotyping (10,731 CRC cases and 10,961 controls from eight centers). In addition to the previously reported 8q24, 15q13 and 18q21 CRC risk loci, we identified two previously unreported associations: rs10795668, located at 10p14 (P = 2.5 x 10(-13) overall; P = 6.9 x 10(-12) replication), and rs16892766, at 8q23.3 (P = 3.3 x 10(-18) overall; P = 9.6 x 10(-17) replication), which tags a plausible causative gene, EIF3H. These data provide further evidence for the 'common-disease common-variant' model of CRC predisposition. 相似文献
99.
ATM mutations that cause ataxia-telangiectasia are breast cancer susceptibility alleles 总被引:13,自引:0,他引:13
Renwick A Thompson D Seal S Kelly P Chagtai T Ahmed M North B Jayatilake H Barfoot R Spanova K McGuffog L Evans DG Eccles D;Breast Cancer Susceptibility Collaboration 《Nature genetics》2006,38(8):873-875
We screened individuals from 443 familial breast cancer pedigrees and 521 controls for ATM sequence variants and identified 12 mutations in affected individuals and two in controls (P = 0.0047). The results demonstrate that ATM mutations that cause ataxia-telangiectasia in biallelic carriers are breast cancer susceptibility alleles in monoallelic carriers, with an estimated relative risk of 2.37 (95% confidence interval (c.i.) = 1.51-3.78, P = 0.0003). There was no evidence that other classes of ATM variant confer a risk of breast cancer. 相似文献
100.
It is important that migration is measured accurately, for example to inform population estimates and projections. However, current sources of information make it difficult to produce robust estimates of emigration from Great Britain. Several other countries, including Ireland, make use of household surveys in their estimates of migration. To investigate the feasibility of obtaining information on emigration from those resident in Great Britain, three questions were included in the Omnibus Survey for two months. Respondents were asked whether they had plans to emigrate or whether anyone in their family had recently emigrated or intended to shortly. This article reports on the results of this pilot, providing evidence on response levels, comparison with the International Passenger Survey and feedback from interviewers on the questions asked. 相似文献