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601.
KNL1 is an evolutionarily conserved kinetochore-associated protein essential for accurate chromosome segregation in eukaryotic cells. This large scaffold protein, predicted to be almost entirely unstructured, is involved in diverse mitotic processes including kinetochore assembly, chromosome congression, and mitotic checkpoint signaling. How this kinetochore “hub” coordinates protein–protein interactions spatially and temporally during mitosis to orchestrate these processes is an area of active investigation. Here we summarize the current understanding of KNL1 and discuss possible mechanisms by which this protein actively contributes to multiple aspects of mitotic progression. 相似文献
602.
G W Warr D DeLuca D P Anderson 《Comparative biochemistry and physiology. B, Comparative biochemistry》1983,76(3):515-521
Thymic lymphocytes of the rainbow trout, S. gairdneri were disrupted and a plasma membrane containing fraction isolated by differential and buoyant density centrifugation. Radioiodine introduced into the membrane by the lactoperoxidase catalyzed reaction and immunoglobulin (identified by radioimmunoassay with monoclonal antibody) both copurified in the plasma membrane fraction. Rabbit antibody raised to the plasma membrane fraction showed a strong reaction with trout lymphocytes in immunofluorescence, was mitogenic for trout lymphocytes, and recognized lymphocyte membrane heteroantigens of molecular weight greater than 70,000 in the thymus and 45,000-95,000 in the head kidney. 相似文献
603.
1,25-Dihydroxyvitamin D3 stimulated increase of 7,8-didehydrocholesterol levels in rat skin 总被引:1,自引:0,他引:1
R P Esvelt H F DeLuca J K Wichmann S Yoshizawa J Zurcher M Sar W E Stumpf 《Biochemistry》1980,19(26):6158-6161
A convenient, accurate assay was developed for determining skin cholesta-5,7-dien-3 beta-ol (7,8-didehydrocholesterol) concentrations. Ultraviolet spectrophotometry provided quantitation of the sterol from rat skins following saponification and chromatography on Lipidex and high-performance liquid chromatography. Correction for recoveries was accomplished by using 7,8-didehydro[3 alpha-3H]cholesterol as an internal standard. Chronic dosing of vitamin D-deficient rats with 1,25-dihydroxyvitamin D3 caused a 4-fold increase in skin 7-dehydrocholesterol content. This rise was not the result of changes in food consumption, body weight, or plasma calcium. Cholesterol concentrations were not significantly elevated although some of the other nonsaponifiable lipid components found in the high-performance liquid chromatogram appeared to be increased by the treatment. These results suggest that the vitamin D hormone 1,25-(OH)2D3 may exert a positive feedback regulation on the production of vitamin D3 in skin. 相似文献
604.
The regulation of calciferol-25-hydroxylase in the chick 总被引:4,自引:0,他引:4
M H Bhattacharyya H F DeLuca 《Biochemical and biophysical research communications》1974,59(2):734-741
605.
Using differential hybridization techniques to screen a rat intestinal cDNA library we isolated a cDNA whose predicted amino acid sequence exhibits a high degree of homology to the alkaline phosphatases. The predicted cDNA sequence has 79% identity at the amino acid level to the rat intestinal alkaline phosphatase, and shows approx. 70% homology to other human and rat alkaline phosphatases. The corresponding mRNA is markedly increased by 6 h after a single dose of 1,25-dihydroxyvitamin D-3. The mRNA is also increased by 24-homologated analogs of 1,25-dihydroxyvitamin D-3 that do not increase calcium transport. 相似文献
606.
607.
Recent advances in the metabolism and function of vitamin D 总被引:10,自引:0,他引:10
H F DeLuca 《Federation proceedings》1969,28(5):1678-1689
608.
Vitamin D3-3 beta-sulfate has been synthesized using pyridine sulfur trioxide as the sulfate donor. It has been shown to be pure by high performance liquid chromatography and spectral methods. Unlike previous reports, the product has been identified unambiguously as the 3 beta-sulfate ester of vitamin D3 by its ultraviolet, nuclear magnetic resonance, infrared, and mass spectra. The biological activity of vitamin D3-sulfate was then determined in vitamin D-deficient rats. Vitamin D3-sulfate has less than 5% of the activity of vitamin D3 to mobilize calcium from bone and approximately 1% of the ability of vitamin D3 to stimulate calcium transport, elevate serum phosphorus, or support bone calcification. These results disprove previous claims that vitamin D3-sulfate has potent biological activity, and they further do not support the contention that vitamin D-sulfate represents a potent water-soluble form of vitamin D in milk. 相似文献
609.
610.