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941.
942.
Jeroen Middelbeek Kristopher Clark Hanka Venselaar Martijn A. Huynen Frank N. van Leeuwen 《Cellular and molecular life sciences : CMLS》2010,67(6):875-890
The alpha-kinase family represents a class of atypical protein kinases that display little sequence similarity to conventional
protein kinases. Early studies on myosin heavy chain kinases in Dictyostelium discoideum revealed their unusual propensity to phosphorylate serine and threonine residues in the context of an alpha-helix. Although
recent studies show that some members of this family can also phosphorylate residues in non-helical regions, the name alpha-kinase
has remained. During evolution, the alpha-kinase domains combined with many different functional subdomains such as von Willebrand
factor-like motifs (vWKa) and even cation channels (TRPM6 and TRPM7). As a result, these kinases are implicated in a large
variety of cellular processes such as protein translation, Mg2+ homeostasis, intracellular transport, cell migration, adhesion, and proliferation. Here, we review the current state of knowledge
on different members of this kinase family and discuss the potential use of alpha-kinases as drug targets in diseases such
as cancer. 相似文献
943.
设G是有限简单无向图,使G-S的每个分支都包含至少k个点的边割S称为G的k-限制边割。G的k-限制边连通度λk(G)是G的k-限制边割之中最少的边数。定义ξk(G)=min{[U,U-]:U V(G),|U|=k,G[U]是连通的},若λk(G)=ξk(G),则称G是λk-最优的。若任意最小k-限制边割都孤立一个k阶分支,则称图G是超级-λk的。应用范型条件给出了图是λ3-最优和超级-λ3的充分条件。 相似文献
944.
Albertus H. Olivier Gert C. van Rooyen Berthold Firmenich Karl E. Beucke 《清华大学学报》2008,13(Z1):165-170
Currently, some commercial software applications support users to work in an integrated environment. However, this is limited to the suite of models provided by the software vendor and consequently it forces all the parties to use the same software. In contrast, the research described in this paper investigates ways of using standard software applications, which may be specialized for different professional domains. These are linked for effective transfer of information and a binding mechanism is provided to support consistency. The proposed solution was implemented using a CAD application and an independent finite element application in order to verify the theoretical aspects of this work. 相似文献
945.
Jijun Yuan Jessica C. Zweers Jan Maarten van Dijl Ross E. Dalbey 《Cellular and molecular life sciences : CMLS》2010,67(2):179-199
In the three domains of life, the Sec, YidC/Oxa1, and Tat translocases play important roles in protein translocation across
membranes and membrane protein insertion. While extensive studies have been performed on the endoplasmic reticular and Escherichia coli systems, far fewer studies have been done on archaea, other Gram-negative bacteria, and Gram-positive bacteria. Interestingly,
work carried out to date has shown that there are differences in the protein transport systems in terms of the number of translocase
components and, in some cases, the translocation mechanisms and energy sources that drive translocation. In this review, we
will describe the different systems employed to translocate and insert proteins across or into the cytoplasmic membrane of
archaea and bacteria. 相似文献
946.
L. Massart G. Peeters J. de Ley R. Vercauteren A. van Houcke 《Cellular and molecular life sciences : CMLS》1947,3(7):288-289
Résumé Les acridines forment avec les nucléoprotéides des levures, des complexes électro-adsorptifs. Le pouvoir bactéricide des acridines s'exerce par une compétition entre les ion H+ de ce complexe et l'ion acridine. Différents enzymes activés par des ions métalliques doivent leur activité catalytique au même type de complexes. Les acridines inhibent ces enzymes parce qu'ils déplacent le cathion métallique. 相似文献
947.
O T Njajou N Vaessen M Joosse B Berghuis J W van Dongen M H Breuning P J Snijders W P Rutten L A Sandkuijl B A Oostra C M van Duijn P Heutink 《Nature genetics》2001,28(3):213-214
Hereditary hemochromatosis (HH) is a very common disorder characterized by iron overload and multi-organ damage. Several genes involved in iron metabolism have been implicated in the pathology of HH (refs. 1-4). We report that a mutation in the gene encoding Solute Carrier family 11, member A3 (SLC11A3), also known as ferroportin, is associated with autosomal dominant hemochromatosis. 相似文献
948.
Jacob A. Bikker Laura Spierdijk Roy P. M. M. Hoevenaars Pieter Jelle Van der Sluis 《Journal of forecasting》2008,27(1):21-39
Often, a relatively small group of trades causes the major part of the trading costs on an investment portfolio. Consequently, reducing the trading costs of comparatively few expensive trades would already result in substantial savings on total trading costs. Since trading costs depend to some extent on steering variables, investors can try to lower trading costs by carefully controlling these factors. As a first step in this direction, this paper focuses on the identification of expensive trades before actual trading takes place. However, forecasting market impact costs appears notoriously difficult and traditional methods fail. Therefore, we propose two alternative methods to form expectations about future trading costs. Applied to the equity trades of the world's second largest pension fund, both methods succeed in filtering out a considerable number of trades with high trading costs and substantially outperform no‐skill prediction methods. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
949.
Jeroen van Dongen 《Archive for History of Exact Sciences》2009,63(6):655-663
This article discusses new material, published in volume 12 of the Collected Papers of Albert Einstein, that addresses Einstein’s
knowledge of the Michelson–Morley experiment prior to 1905: in a lecture in Chicago in 1921, Einstein referred to the experiment,
mentioned when he came upon it and hinted at its influence. Arguments are presented to explain the contrast with Einstein’s
later pronouncements on the role of the experiment. 相似文献
950.