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991.
992.
993.
V V Tertov I A Sobenin Z A Gabbasov E G Popov A N Orekhov 《Biulleten' eksperimental'no? biologii i meditsiny》1990,110(7):34-36
Spontaneous aggregation of glycosylated, desialated, oxidized and malondialdehyde modified low density lipoprotein (LDL) as well as LDL of coronary heart disease patients has been discovered using methods for determination of light transmission fluctuations in suspensions and gel filtration. At the same time; LDL of healthy donors failed to aggregate under conditions of cellular culture. On the other hand, human aortic cells from unaffected intima incubated with modified LDL, but not native LDL of healthy donors, showed a rise in esterified cholesterol levels. There was a strong correlation between the degree of LDL aggregation and intracellular cholesterol ester accumulation (r-0.86, p 0.001, n-21). Removal of aggregates by passing preparations through and 0.1 um filter significantly inhibited the accumulation of cholesterol esters. The obtained data point to the essential, if not decisive, role of LDL aggregation in the processes of lipid accumulation by intimal cells in vitro. 相似文献
994.
We evaluated VER effect on RNA synthesis of quiescent and angiotensin II (AII)- stimulated cultured rat aortic vascular smooth muscle cells (VSMC). In a dose-dependent manner, VER decreased [3H]uridine uptake by quiescent VSMCs (ED50 7 x 10(-6)M), an effect that was shared by other calcium antagonists, but to a variable degree. VER caused a significant effect within 3 hours and attained a maximal effect at 7 hours. In addition VER caused a 22 +/- 2% decrease in [3H]uridine uptake by VSMCs stimulated with 10% fetal bovine serum, while it completely abolished [3H]uridine uptake by VSMCs induced by AII. We conclude that VER decreases basal and inhibits AII-induced increase in mRNA synthesis of VSMCs. These data may explain in part how VER causes a decrease in vascular resistance and alters the vasoconstrictor effect of AII. 相似文献
995.
Xu Zhang Wei Zhang Santosh L. Saraf Mehdi Nouraie Jin Han Michel Gowhari Johara Hassan Galina Miasnikova Adelina Sergueeva Sergei Nekhai Rick Kittles Roberto F. Machado Joe G. N. Garcia Mark T. Gladwin Martin H. Steinberg Paola Sebastiani Donald A. McClain Victor R. Gordeuk 《Human genetics》2015,134(8):895-904
996.
N. Fujii N. Tomaru K. Okuyama T. Koike T. Mikami K. Ueda 《Plant Systematics and Evolution》2002,232(1-2):21-33
CpDNA variation in Japanese beech, Fagus crenata (Fagaceae), was studied in 45 populations distributed throughout the species' range. Two cpDNA regions were sequenced: the
non-coding region between the trnL (UAA) 5′exon and trnF (GAA), and the trnK region (including matK). Thirteen distinct cpDNA haplotypes were recognized and each haplotype was found to be geographically structured. Two major
clades (I and II+III) were revealed in phylogenetic analyses among the haplotypes using F. sylvatica as an outgroup. The haplotypes of Clade I were distributed mainly along the Japan Sea side of the Japanese Archipelago, while
those of Clade II+III occurred chiefly along the Pacific Ocean side. Consequently, the distribution of the two major cpDNA
clades suggests that there were two migration routes in the history of F. crenata; one along the Japan Sea and the other along the Pacific Ocean side of the Japanese Islands.
Received March 19, 2001 Accepted November 22, 2001 相似文献
997.
998.
999.
Corinna Richter Ron L. Dy Rebecca E. McKenzie Bridget N.J. Watson Corinda Taylor James T. Chang Matthew B. McNeil Raymond H.J. Staals Peter C. Fineran 《Nucleic acids research》2014,42(13):8516-8526
Clustered regularly interspaced short palindromic repeats (CRISPR), in combination with CRISPR associated (cas) genes, constitute CRISPR-Cas bacterial adaptive immune systems. To generate immunity, these systems acquire short sequences of nucleic acids from foreign invaders and incorporate these into their CRISPR arrays as spacers. This adaptation process is the least characterized step in CRISPR-Cas immunity. Here, we used Pectobacterium atrosepticum to investigate adaptation in Type I-F CRISPR-Cas systems. Pre-existing spacers that matched plasmids stimulated hyperactive primed acquisition and resulted in the incorporation of up to nine new spacers across all three native CRISPR arrays. Endogenous expression of the cas genes was sufficient, yet required, for priming. The new spacers inhibited conjugation and transformation, and interference was enhanced with increasing numbers of new spacers. We analyzed ∼350 new spacers acquired in priming events and identified a 5′-protospacer-GG-3′ protospacer adjacent motif. In contrast to priming in Type I-E systems, new spacers matched either plasmid strand and a biased distribution, including clustering near the primed protospacer, suggested a bi-directional translocation model for the Cas1:Cas2–3 adaptation machinery. Taken together these results indicate priming adaptation occurs in different CRISPR-Cas systems, that it can be highly active in wild-type strains and that the underlying mechanisms vary. 相似文献
1000.
J T Rogers K R Bridges G P Durmowicz J Glass P E Auron H N Munro 《The Journal of biological chemistry》1990,265(24):14572-14578
Interleukin-1 (IL-1 beta) increases the synthesis of both heavy and light (L)-ferritin subunits when added to human hepatoma cells (HepG2) grown in culture. RNase protection and Northern blot analysis with L-ferritin probes revealed that no changes in L-ferritin mRNA levels occur after cytokine stimulation. However, the induction coincides with an increased association of the L-subunit mRNA with polyribosomes. Since the recruitment of stored ferritin mRNA onto polyribosomes is seen when iron enters the cell, the effect of IL-1 beta on iron uptake was tested and was found to be unaffected by the lymphokine. Neither transferrin receptor mRNA levels nor the number of receptors displayed on the cell surface was affected by IL-1 beta. However, the action of the cytokine on ferritin translation is inhibited by the action of the intracellular iron chelator deferoxamine. These data indicate that IL-1 beta induces ferritin gene expression by translational control of its mRNA. The pathway of induction is different from iron-dependent ferritin gene expression whereas regulation requires the background presence of cellular iron. 相似文献