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951.
Plasma membranes of cells isolated from higher plant were permeabilizedby a combination of plasmolysis and deplasmolysis in the presenceof EGTA. Permeabilized cells, with intact vacuoles, could beseparated from intact cells by density gradient centrifugation.The evolution of oxygen in permeabilized cells was measuredin the presence of PGA. (Received February 20, 1992; Accepted May 25, 1992) 相似文献
952.
Linkage Disequilibrium and Haplotype Studies of Chromosome 8p 11.1-21.1 Markers and Werner Syndrome 总被引:2,自引:2,他引:0 下载免费PDF全文
Chang-En Yu Junko Oshima Katrina A. B. Goddard Tetsuro Miki Jun Nakura Toshio Ogihara Martin Poot Holger Hoehn Marco Fraccaro Charles Piussan George M. Martin Gerard D. Schellenberg Ellen M. Wijsman 《American journal of human genetics》1994,55(2):356-364
Werner syndrome (WS) is an autosomal recessive disorder, characterized as a progeroid syndrome, previously mapped to the 8p 11.1-21.1 region. Because WS is so rare, and because many patients are from consanguineous marriages, fine localization of the gene by traditional meiotic mapping methods is unlikely to succeed. Here we present the results of a search for a region that exhibits linkage disequilibrium with the disorder, under the assumption that identification of such a region may provide an alternative method of narrowing down the location of WRN, the gene responsible for WS. We present allele frequencies in Japanese and Caucasian cases and controls for D8S137, D8S131, D8S87, D8S278, D8S259, D8S283, fibroblast growth factor receptor 1, ankyrin 1, D8S339, and two polymorphisms in glutathione reductase (GSR), covering ~16.5 cM in total. We show that three of the markers examined—D8S339 and both polymorphisms in the GSR locus—show strong statistically significant evidence of disequilibrium with WRN in the Japanese population but not in the Caucasian population. In addition, we show that a limited number of haplotypes are associated with the disease in both populations and that these haplotypes define clusters of apparently related haplotypes that may identify as many as eight or nine independent WRN mutations in these two populations. 相似文献
953.
The effect of the culture media on the composition of the outer membrane protein of Vibrio vulnificus strain 393 from human blood was examined. Only one major outer membrane protein, with an apparent molecular weight of 37,000 (37K protein) and 34,000 (34K protein), was formed in the cells grown in 3% NaCl-BHI broth and chemically defined medium, respectively. The production of one major outer membrane protein was also observed in other isolates from humans and asari clam when they were grown in 3% NaCl-BHI broth. On the other hand, three major outer membrane proteins, with apparent molecular weights of 48,000 (48K protein), 37,000 (37K protein), and 34,000 (34K protein), were produced in the cells grown in 3% NaCl-nutrient broth. Three proteins, 48K, 37K, and 34K from strain 393, were purified and the amino acid compositions were determined. Although there was a little difference in the composition of amino acid among three proteins, the amino acid compositions of the three porin-like proteins showed characteristic properties of the porins of Escherichia coli and Salmonella typhimurium. Immunoblot analysis of the outer membrane proteins from four vibrios, E. coli, and S. typhimurium using monospecific antisera against these three porin-like proteins showed that only the antiserum against 37K protein cross-reacted with the outer membrane proteins from all the strains tested. 相似文献
954.
Shikama H Miyata K Sakae N Kuroda K Nishimura K Yotsuya S Kato M 《Mediators of inflammation》1994,3(2):111-116
The effects of human tumour necrosis factor-alpha (TNFalpha), or its mutein (F4168) having the cell adhesive Arg-Gly-Asp sequence at the N-terminus, on intestinal injury, were examined. Histopathological examination revealed that an intravenous injection of TNFalpha resulted in marked haemorrhage or oedema in the caecum of rats, whereas F4168 showed no such effects even at the same therapeutic dose. Moreover, the number of neutrophils that adhered to endothelial cells or infiltrated the mucosal tissue was much higher after TNFalpha injection compared with F4168 in vivo. The enhanced adhesion of neutrophils on to human umbilical vein endothelial cells also occurred when the latter were pre-stimulated with TNFalpha but not with F4168 in vitro. The expression of the cell adhesion molecules including endothelial leukocyte adhesion molecule-1 or intercellular adhesion molecule-1 on F4168- stimulated human umbilical vein endothelial ceils was significantly lower than that stimulated with TNFalpha. These results suggest that the Arg-Gly-Asp sequence introduced into the TNFalpha molecule abrogates the side effect of this cytokine such as tissue injury or shock, and that F4168 could be useful for systemic therapy. 相似文献
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958.
Structural comparison of bovine erythrocyte, brain, and liver NADH-cytochrome b5 reductase by HPLC mapping 总被引:3,自引:0,他引:3
M Tamura T Yubisui M Takeshita S Kawabata T Miyata S Iwanaga 《Journal of biochemistry》1987,101(5):1147-1159
NADH-cytochrome b5 reductases purified from bovine erythrocytes and from bovine brain and liver microsomes solubilized with lysosomal protease were subjected to structural analysis by using HPLC mapping, amino acid analysis of the resulting peptides, and NH2-terminal sequence analysis of apoproteins. HPLC maps of the tryptic peptides derived from these enzymes were very similar to each other, and amino acid analysis of the HPLC-separated peptides indicated that the structures of these enzymes are identical except for the NH2-terminal region. The NH2-terminal sequence of the brain enzyme determined by automated Edman degradation was as follows: NH2-Phe-Gln-Arg-Ser-Thr-Pro-Ala-Ile-Thr-Leu-Glu-Asn-Pro-Asp- Ile-Lys-Tyr-Pro-Leu-Arg-Leu-Ile-Asp-Lys-Glu-Val-Ile- This sequence is identical to that of liver enzyme except that the liver enzyme started at the 3rd Arg or 4th Ser. The NH2-terminal amino acid residue of the soluble erythrocyte enzyme was not detected by automated Edman degradation. The sequence analysis of a tryptic peptide from the erythrocyte enzyme indicated that Leu is present before the NH2-terminal Phe of the brain enzyme. The recently reported sequence of the apparently identical protein (Ozols et al. (1985) J. Biol. Chem. 260, 11953-11961) differs in two amino acid assignments from our sequence. 相似文献
959.
Summary Reflecting chromatophores in the dermis of the skin of a freshwater goby, Odontobutis obscura, are of an iridophore type. These chromatophores contain numerous reflecting platelets, which are similar to those in iridophores of other fish and amphibian species. It was found that these iridophores are motile, i.e., these cells respond to certain stimuli with translocation of the platelets within the cells. K+ ions induced dispersion of the platelets in excised scale preparations, but not in excised scales from chemically denervated fish. Norepinephrine and melatonin also induced dispersion of the platelets. Alpha-MSH was effective in aggregating these organelles into the centrospheres of the cells. The conclusions reached are: (1) iridophores of O. obscura are motile; (2) the movement of the iridophores is under nervous and hormonal control. 相似文献
960.