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101.
D. H. Schlesinger J. D. Capra I. L. Schwartz R. Walter 《Cellular and molecular life sciences : CMLS》1971,27(2):213-213
Zusammenfassung Durch Spaltung mit CNBr wurde gezeigt, dass Neurophysin II aus Rinderhypophyse nur eine Methionin-Einheit enthält und dass die N-terminale Sequenz Ala-Met ist.
This work was supported by NIH Grants No. AM-13567, No. AM-10080, by NSF Grant No. GB-17046 and by the City University of New York. The authors are indebted to Dr.L. Abrash for helpful discussion and MissM. Wahrenburg and Mr.V. S. Sapirstein for the assays.
Predoctoral fellow of the Department of Physiology. 相似文献
This work was supported by NIH Grants No. AM-13567, No. AM-10080, by NSF Grant No. GB-17046 and by the City University of New York. The authors are indebted to Dr.L. Abrash for helpful discussion and MissM. Wahrenburg and Mr.V. S. Sapirstein for the assays.
Predoctoral fellow of the Department of Physiology. 相似文献
102.
103.
Stromatolite reef from the Early Archaean era of Australia 总被引:3,自引:0,他引:3
The 3,430-million-year-old Strelley Pool Chert (SPC) (Pilbara Craton, Australia) is a sedimentary rock formation containing laminated structures of probable biological origin (stromatolites). Determining the biogenicity of such ancient fossils is the subject of ongoing debate. However, many obstacles to interpretation of the fossils are overcome in the SPC because of the broad extent, excellent preservation and morphological variety of its stromatolitic outcrops--which provide comprehensive palaeontological information on a scale exceeding other rocks of such age. Here we present a multi-kilometre-scale palaeontological and palaeoenvironmental study of the SPC, in which we identify seven stromatolite morphotypes--many previously undiscovered--in different parts of a peritidal carbonate platform. We undertake the first morphotype-specific analysis of the structures within their palaeoenvironment and refute contemporary abiogenic hypotheses for their formation. Finally, we argue that the diversity, complexity and environmental associations of the stromatolites describe patterns that--in similar settings throughout Earth's history--reflect the presence of organisms. 相似文献
104.
Rapid X-ray flaring from the direction of the supermassive black hole at the Galactic Centre. 总被引:2,自引:0,他引:2
F K Baganoff M W Bautz W N Brandt G Chartas E D Feigelson G P Garmire Y Maeda M Morris G R Ricker L K Townsley F Walter 《Nature》2001,413(6851):45-48
The nuclei of most galaxies are now believed to harbour supermassive black holes. The motions of stars in the central few light years of our Milky Way Galaxy indicate the presence of a dark object with a mass of about 2.6 x 106 solar masses (refs 2, 3). This object is spatially coincident with the compact radio source Sagittarius A* (Sgr A*) at the dynamical centre of the Galaxy, and the radio emission is thought to be powered by the gravitational potential energy released by matter as it accretes onto a supermassive black hole. Sgr A* is, however, much fainter than expected at all wavelengths, especially in X-rays, which has cast some doubt on this model. The first strong evidence for X-ray emission was found only recently. Here we report the discovery of rapid X-ray flaring from the direction of Sgr A*, which, together with the previously reported steady X-ray emission, provides compelling evidence that the emission is coming from the accretion of gas onto a supermassive black hole at the Galactic Centre. 相似文献
105.
本书提供了一个对解析的电子结构的说明,以便与计算的电子结构相互区分。这两者都是建立在单电子近似、局部密度理论和量子机理电子态确定的基础之上的。这两种方法都是以这些状态为基础。寻求合成的固体或者分子性质的预测。本书是1999年出版的教课书《固体的电子结构与性质》一书的修订版。书中增加了有关玻璃的一章,并且重新撰写了有关旋转轨道耦合、磁合金与锕系元素的章节。 相似文献
106.
107.
Mills RE Walter K Stewart C Handsaker RE Chen K Alkan C Abyzov A Yoon SC Ye K Cheetham RK Chinwalla A Conrad DF Fu Y Grubert F Hajirasouliha I Hormozdiari F Iakoucheva LM Iqbal Z Kang S Kidd JM Konkel MK Korn J Khurana E Kural D Lam HY Leng J Li R Li Y Lin CY Luo R Mu XJ Nemesh J Peckham HE Rausch T Scally A Shi X Stromberg MP Stütz AM Urban AE Walker JA Wu J Zhang Y Zhang ZD Batzer MA Ding L Marth GT McVean G Sebat J Snyder M Wang J Ye K Eichler EE Gerstein MB Hurles ME Lee C McCarroll SA 《Nature》2011,470(7332):59-65
Genomic structural variants (SVs) are abundant in humans, differing from other forms of variation in extent, origin and functional impact. Despite progress in SV characterization, the nucleotide resolution architecture of most SVs remains unknown. We constructed a map of unbalanced SVs (that is, copy number variants) based on whole genome DNA sequencing data from 185 human genomes, integrating evidence from complementary SV discovery approaches with extensive experimental validations. Our map encompassed 22,025 deletions and 6,000 additional SVs, including insertions and tandem duplications. Most SVs (53%) were mapped to nucleotide resolution, which facilitated analysing their origin and functional impact. We examined numerous whole and partial gene deletions with a genotyping approach and observed a depletion of gene disruptions amongst high frequency deletions. Furthermore, we observed differences in the size spectra of SVs originating from distinct formation mechanisms, and constructed a map of SV hotspots formed by common mechanisms. Our analytical framework and SV map serves as a resource for sequencing-based association studies. 相似文献
108.
Dorner M Horwitz JA Robbins JB Barry WT Feng Q Mu K Jones CT Schoggins JW Catanese MT Burton DR Law M Rice CM Ploss A 《Nature》2011,474(7350):208-211
Hepatitis C virus (HCV) remains a major medical problem. Antiviral treatment is only partially effective and a vaccine does not exist. Development of more effective therapies has been hampered by the lack of a suitable small animal model. Although xenotransplantation of immunodeficient mice with human hepatocytes has shown promise, these models are subject to important challenges. Building on the previous observation that CD81 and occludin comprise the minimal human factors required to render mouse cells permissive to HCV entry in vitro, we attempted murine humanization via a genetic approach. Here we show that expression of two human genes is sufficient to allow HCV infection of fully immunocompetent inbred mice. We establish a precedent for applying mouse genetics to dissect viral entry and validate the role of scavenger receptor type B class I for HCV uptake. We demonstrate that HCV can be blocked by passive immunization, as well as showing that a recombinant vaccinia virus vector induces humoral immunity and confers partial protection against heterologous challenge. This system recapitulates a portion of the HCV life cycle in an immunocompetent rodent for the first time, opening opportunities for studying viral pathogenesis and immunity and comprising an effective platform for testing HCV entry inhibitors in vivo. 相似文献
109.
Walter Riofrio 《Foundations of Science》2012,17(3):277-289
Lately there has been a growing interest in evolutionary studies concerning how the regularities and patterns found in the living cell could have emerged spontaneously by way of self-assembly and self-organization. It is reasonable to postulate that the chemical compounds found in the primitive Earth would have mostly been very simple in nature, and would have been immersed in the natural dynamics of the physical world, some of which would have involved self-organization. It seems likely that some molecular processes self-organized spontaneously into a hierarchy of complex behaviours. Our conceptual search herein reaches back to the time when prebiotic phenomena began to take shape. This was before the origin of life, so in this paper we hope to shed new light on some of the theoretical issues that surround the ways in which cellular organization might have evolved without the aid of replicated information. 相似文献
110.
我们对柏拉图之前的希腊情况知之甚少,然而公元前6世纪出现的一种特殊文学样式留下了宝贵的历史资料。在这个时期曾经有一些视野较为宽阔的关于宇宙及其起源的书籍问世,它们在特殊的环境中获得繁荣。这些书籍主要由两条支流——思想和文学汇集而成,它们超越了狭小的地域边界,广为流传的是:智慧的宣言和宇宙开创的神话。到目前为止,我们没有理由将希腊人——荷马,赫西俄德或俄耳甫斯神话的宇宙发生论从其东方副本(极相似的人或物)中分离出来。很明显,它们出自同一个家庭,而且有不少证据显示出前苏格拉底的哲学家们依然在步东方宇宙发生论的后尘。 相似文献