全文获取类型
收费全文 | 601959篇 |
免费 | 58228篇 |
国内免费 | 406篇 |
专业分类
660593篇 |
出版年
2018年 | 5582篇 |
2016年 | 7057篇 |
2015年 | 8384篇 |
2014年 | 10453篇 |
2013年 | 14930篇 |
2012年 | 17036篇 |
2011年 | 17670篇 |
2010年 | 12111篇 |
2009年 | 10928篇 |
2008年 | 15702篇 |
2007年 | 16444篇 |
2006年 | 15657篇 |
2005年 | 14985篇 |
2004年 | 15043篇 |
2003年 | 14351篇 |
2002年 | 14321篇 |
2001年 | 26297篇 |
2000年 | 26543篇 |
1999年 | 20932篇 |
1998年 | 6772篇 |
1997年 | 6873篇 |
1996年 | 6386篇 |
1995年 | 6055篇 |
1994年 | 5966篇 |
1993年 | 5868篇 |
1992年 | 16925篇 |
1991年 | 16797篇 |
1990年 | 16458篇 |
1989年 | 16076篇 |
1988年 | 15132篇 |
1987年 | 14283篇 |
1986年 | 13400篇 |
1985年 | 13727篇 |
1984年 | 11170篇 |
1983年 | 9506篇 |
1982年 | 7143篇 |
1981年 | 6516篇 |
1980年 | 6100篇 |
1979年 | 10710篇 |
1978年 | 8514篇 |
1977年 | 7841篇 |
1976年 | 7468篇 |
1975年 | 8582篇 |
1974年 | 9522篇 |
1973年 | 9424篇 |
1972年 | 8628篇 |
1971年 | 7920篇 |
1970年 | 6836篇 |
1969年 | 6736篇 |
1968年 | 6178篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
T. S. Serchenya A. G. Pryadko O. V. Sviridov 《Applied Biochemistry and Microbiology》2009,45(3):326-333
Four monoclonal antibodies (mAbs), G6, F9, H8, and B2, against human alpha-1-microglobulin (A1M) have been produced and characterized. The parameters of affinity (Kp ~ 109 M?1), epitope specificity (the additively binding G6/F9, G6/H8, G6/B2, F9/H8, and F9/B2 pairs), and the observed effect of reversibility of structural changes induced by chemical agents allow use of these mAbs in biospecific methods of A1M purification and quantitative determination. The application of mAbs to an A1M enzyme immunoassay (analytical sensitivity—0.5 μg/l) and one step isolation of pure A1M by immunoaffinity chromatography was described. 相似文献
992.
The interaction between human plasma lipoproteins and connective tissue glycosaminoglycans 总被引:29,自引:0,他引:29
P H Iverius 《The Journal of biological chemistry》1972,247(8):2607-2613
993.
994.
G V Kolusheva 《Arkhiv anatomii, gistologii i émbriologii》1987,93(7):10-15
The electron microscopic method has revealed early maturation of the protein-synthesizing apparatus of some cells, on the one hand, and underdevelopment of neuroblast volumes, appearance of artificial contacts, axonal degeneration and destruction in large trunks, on the other hand. Compensatory-restorative processes in the cell on the 14th and 21st days of the postnatal development result in a complete restoration of morphological organization of neurons and interneuronal connections in the hypothalamus of offspring of the morphine-dependent rats. 相似文献
995.
996.
M R Kopantseva M Z Liudvig I I Uspenski? N A Tamarina V A Tsatrian L I Korochkin 《Zhurnal obshche? biologii》1990,51(1):125-140
A comparative electrophoretic study or ejaculatory bulb proteins in 29 different Drosophila species has been carried out. In all analyzed species, ejaculatory bulb contains a major component (designated as PEB). It has molecular mass of 61-65 kDa in the species of virilis group, 33-36 kDa in species of obscura group, and 34-56 kDa in species of melanogaster group. Using immunoblotting technique, we have demonstrated that PEB is introduced into organs of female sex tract during mating. The nature and significance of revealed interspecific differences in PEB proteins has been discussed. 相似文献
997.
When the roots of Vicia faba L. beans were subjected to hypoxic stress, the activity of H+-ATPase on the peribacteroid membrane, as well as the transport of dicarboxylates (malate and succinate) mediated by this
enzyme, decreased. Since malate and succinate are the main carbon-containing metabolites involved in the energy supply to
bacteroids, this caused a change of the relation type from mutualism to commensalism, and the domination of the eukaryotes
over the prokaryotes consequently increased. 相似文献
998.
S Ikei M Ogawa T Beppu C Ohara K Sakamoto H Sameshima H Arakawa Y Yamaguchi T Yamanaka S Kudo 《Cytokine》1992,4(6):581-584
In an attempt to investigate the interaction between the changes of cytokines and acute phase reactants after transcatheter arterial chemoembolization therapy (TACE), the levels of interleukin 6 (IL-6), interleukin 8 (IL-8), C-reactive protein (CRP) and pancreatic secretory trypsin inhibitor (PSTI) in the blood of patients with unresectable hepatocellular carcinoma (HCC) were measured. Before the therapy, serum IL-6 and plasma IL-8 levels were detectable in 77.8% and 28.5%, respectively, of patients with HCC. Levels of serum IL-6 and plasma IL-8 increased after TACE and reached a peak on day 3 in all patients (18/18) and in 87.5% of patients (12/14), respectively. Both blood levels of IL-6 and IL-8 reached a peak earlier than those of CRP and PSTI did after the therapy. When the maximal values of IL-6 were compared with those of CRP and PSTI, there were significant positive correlations (r = 0.63, P < 0.01 and r = 0.81, P < 0.01, respectively). Similarly, comparisons of the maximal values of IL-8 with those of CRP and PSTI gave a significant correlation (r = 0.68, P < 0.01 and r = 0.67, P < 0.05, respectively). However, no significant correlation was found between the elevation of IL-6 and IL-8. 相似文献
999.
1000.
P. Cruz C. H. Mejia‐Ruiz R. Perez‐Enriquez A. M. Ibarra 《Molecular ecology resources》2002,2(3):239-241
Five polymorphic microsatellite loci were characterized for Penaeus (Litopenaeus) vannamei. Loci were isolated using a partial Sau3A1 genomic library by the sequencing of randomly selected clones and by a biotinylated (CT)10 and (GT)10 probes screening procedure. The last strategy resulted in the most useful data. About 40% of the clones showed a previously reported satellite/microsatellite (PVS1), reducing the chance of finding new microsatellite regions. Whereas two of the microsatellite loci with more than 10 alleles will be useful for mating analysis in a breeding program, the others might prove useful for population genetic studies. 相似文献