全文获取类型
收费全文 | 1155篇 |
免费 | 0篇 |
专业分类
系统科学 | 13篇 |
教育与普及 | 2篇 |
理论与方法论 | 18篇 |
现状及发展 | 444篇 |
研究方法 | 174篇 |
综合类 | 498篇 |
自然研究 | 6篇 |
出版年
2018年 | 10篇 |
2017年 | 12篇 |
2016年 | 11篇 |
2014年 | 14篇 |
2013年 | 10篇 |
2012年 | 61篇 |
2011年 | 76篇 |
2010年 | 26篇 |
2009年 | 7篇 |
2008年 | 45篇 |
2007年 | 56篇 |
2006年 | 59篇 |
2005年 | 58篇 |
2004年 | 31篇 |
2003年 | 31篇 |
2002年 | 41篇 |
2001年 | 34篇 |
2000年 | 43篇 |
1999年 | 39篇 |
1992年 | 31篇 |
1991年 | 11篇 |
1990年 | 9篇 |
1989年 | 10篇 |
1988年 | 11篇 |
1987年 | 19篇 |
1986年 | 15篇 |
1985年 | 27篇 |
1984年 | 15篇 |
1983年 | 13篇 |
1982年 | 8篇 |
1981年 | 9篇 |
1980年 | 11篇 |
1979年 | 23篇 |
1978年 | 18篇 |
1977年 | 13篇 |
1976年 | 11篇 |
1975年 | 13篇 |
1974年 | 12篇 |
1973年 | 14篇 |
1972年 | 21篇 |
1971年 | 19篇 |
1970年 | 15篇 |
1969年 | 14篇 |
1968年 | 18篇 |
1967年 | 15篇 |
1966年 | 10篇 |
1965年 | 9篇 |
1964年 | 12篇 |
1956年 | 6篇 |
1947年 | 4篇 |
排序方式: 共有1155条查询结果,搜索用时 15 毫秒
681.
Steidl C Shah SP Woolcock BW Rui L Kawahara M Farinha P Johnson NA Zhao Y Telenius A Neriah SB McPherson A Meissner B Okoye UC Diepstra A van den Berg A Sun M Leung G Jones SJ Connors JM Huntsman DG Savage KJ Rimsza LM Horsman DE Staudt LM Steidl U Marra MA Gascoyne RD 《Nature》2011,471(7338):377-381
682.
683.
Pascal P. H. Hommelberg Jogchum Plat Lauren M. Sparks Annemie M. W. J. Schols Anon L. M. van Essen Marco C. J. M. Kelders Denis van Beurden Ronald P. Mensink Ramon C. J. Langen 《Cellular and molecular life sciences : CMLS》2011,68(7):1215-1225
Palmitate activates the NF-κB pathway, and induces accumulation of lipid metabolites and insulin resistance in skeletal muscle
cells. Little information is available whether and how these processes are causally related. Therefore, the objectives were
to investigate whether intra-cellular lipid metabolites are involved in FA-induced NF-κB activation and/or insulin resistance
in skeletal muscle and to investigate whether FA-induced insulin resistance and NF-κB activation are causally related. Inhibiting
DGAT or CPT-1 by using, respectively, amidepsine or etomoxir increased DAG accumulation and sensitized myotubes to palmitate-induced
insulin resistance. While co-incubation of palmitate with etomoxir increased NF-κB transactivation, co-incubation with amidepsine
did not, indicating that DAG accumulation is associated with insulin resistance but not with NF-κB activation. Furthermore,
pharmacological or genetic inhibition of the NF-κB pathway could not prevent palmitate-induced insulin resistance. In conclusion,
we have demonstrated that activation of the NF-κB pathway is not required for palmitate-induced insulin resistance in skeletal
muscle cells. 相似文献
684.
Summary A method is described that allows blood samples to be taken repeatedly from the suprarenal vein, without changing the circulation in the adrenal glands or eliciting reflexes which could interfere with the adrenalin secretion. The vasoconstrictor properties of the blood samples are tested on an isolated blood vessel preparation. 相似文献
685.
Prokaryotic origin of the actin cytoskeleton. 总被引:47,自引:0,他引:47
It was thought until recently that bacteria lack the actin or tubulin filament networks that organize eukaryotic cytoplasm. However, we show here that the bacterial MreB protein assembles into filaments with a subunit repeat similar to that of F-actin-the physiological polymer of eukaryotic actin. By elucidating the MreB crystal structure we demonstrate that MreB and actin are very similar in three dimensions. Moreover, the crystals contain protofilaments, allowing visualization of actin-like strands at atomic resolution. The structure of the MreB protofilament is in remarkably good agreement with the model for F-actin, showing that the proteins assemble in identical orientations. The actin-like properties of MreB explain the finding that MreB forms large fibrous spirals under the cell membrane of rod-shaped cells, where they are involved in cell-shape determination. Thus, prokaryotes are now known to possess homologues both of tubulin, namely FtsZ, and of actin. 相似文献
686.
B. L. van der Waerden 《Archive for History of Exact Sciences》1972,9(3):240-248
Ohne Zusammenfassung 相似文献
687.
W. J. van Ooij D. Zhu M. Stacy A. Seth T. Mugada J. Gandhi P. Puomi 《清华大学学报》2005,10(6):639-664
The aim of this paper is to review the development and state of the art in the application of certain organosilicon compounds known as trialkoxysilanes (or simply silanes) to the problems of the metal finishing industry. The ultimate goal of this work is the replacement of chromate passivation and paint pretreatments, as well as overcoming the shortcomings of organic coatings formulated in the modern environmentally friendly world, thus without chromate or chromated pigments, volatile organic carbon (VOC) containing compounds or harazardous air pollutants (HAPs). 相似文献
688.
689.
L Hendriks C M van Duijn P Cras M Cruts W Van Hul F van Harskamp A Warren M G McInnis S E Antonarakis J J Martin 《Nature genetics》1992,1(3):218-221
Several families with an early-onset form of familial Alzheimer's disease have been found to harbour mutations at a specific codon (717) of the gene for the beta-amyloid precursor protein (APP) on chromosome 21. We now report, a novel base mutation in the same exon of the APP gene which co-segregates in one family with presenile dementia and cerebral haemorrhage due to cerebral amyloid angiopathy. The mutation results in the substitution of alanine into glycine at codon 692. These results suggest that the clinically distinct entities, presenile dementia and cerebral amyloid angiopathy, can be caused by the same mutation in the APP gene. 相似文献
690.