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961.
R. A. de Zeeuw T. B. Vree D. D. Breimer C. A. M. van Ginneken 《Cellular and molecular life sciences : CMLS》1973,29(3):260-261
Zusammenfassung Es wurde ein neuer Vertreter aus der Gruppe der psychotrop wirkenden Inhaltsstoffe im Haschisch indischer Herkunft gefunden. Es handelt sich um Cannabivarichromen, als Homologa mit einer Propyl-Seitenkette des Cannabichromens. 相似文献
962.
G E de Jonge-Strobel J P Veldhuijzen J W Vermeiden F P van de Wijngaert B Prahl-Andersen 《Experientia》1987,43(2):199-200
A technique is described for in vitro culture of the quail embryo from the 1st to the 18th day of development. The embryos are cultured in Teflon hammocks, suspended in glass supports and kept in a humidified atmosphere at 36.5 degrees C. The quail CAM is used as support and cell source for developing non-quail cartilage and bone. The quail cells can be identified histologically and easily recognized by Feulgen-staining which is demonstrated in the presence of quail chondro- or osteoclasts in a mouse long bone rudiment cultured on the CAM. 相似文献
963.
Mutation in mitochondrial tRNA(Leu)(UUR) gene in a large pedigree with maternally transmitted type II diabetes mellitus and deafness. 总被引:23,自引:0,他引:23
J M van den Ouweland H H Lemkes W Ruitenbeek L A Sandkuijl M F de Vijlder P A Struyvenberg J J van de Kamp J A Maassen 《Nature genetics》1992,1(5):368-371
Non-insulin-dependent (type II) diabetes mellitus (NIDDM) is characterized by hyperglycaemia and insulin resistance, and affects nearly 5% of the general population. Inherited factors are important for its development, but the genes involved are unknown. We have identified a large pedigree in which NIDDM, in combination with a sensorineural hearing loss, is maternally inherited. The maternal inheritance and the observed decrease in mitochondrial enzyme activities of the respiratory chain indicate a genetic defect in the mitochondrial DNA. An A to G transition was identified at nucleotide 3,243, a conserved position in the mitochondrial gene for tRNA(Leu)(UUR). This mutation cosegregates with the disease in this family and is absent in controls, and indicates that a point mutation in mitochondrial DNA is a pathogenetic factor for NIDDM. 相似文献
964.
A Meindl W Berger T Meitinger D van de Pol H Achatz C D?rner M Haasemann H Hellebrand A Gal F Cremers 《Nature genetics》1992,2(2):139-143
A candidate gene for Norrie disease, an X-linked disorder characterized by blindness, deafness and mental disturbances, was recently isolated and found to contain microdeletions in numerous patients. No strong homologies were identified. By studying the number and spacing of cysteine residues, we now detect homologies between the Norrie gene product and a C-terminal domain which is common to a group of proteins including mucins. Three newly-characterized missense mutations, replacing evolutionarily conserved cysteines or creating new cysteine codons, emphasize the functional importance of these sites. These findings and the clinical features of this disorder suggest a possible role for the Norrie gene in neuroectodermal cell-cell interaction. 相似文献
965.
Profound block in thymocyte development in mice lacking p56lck. 总被引:66,自引:0,他引:66
T J Molina K Kishihara D P Siderovski W van Ewijk A Narendran E Timms A Wakeham C J Paige K U Hartmann A Veillette 《Nature》1992,357(6374):161-164
The protein Lck (p56lck) has a relative molecular mass of 56,000 and belongs to the Src family of tyrosine kinases. It is expressed exclusively in lymphoid cells, predominantly in thymocytes and peripheral T cells. Lck associates specifically with the cytoplasmic domains of both CD4 and CD8 T-cell surface glycoproteins and interacts with the beta-chain of the interleukin-2 receptor, which implicates Lck activity in signal transduction during thymocyte ontogeny and activation of mature T cells. Here we generate an lck null mutation by homologous recombination in embryonic stem cells to evaluate the role of p56lck in T-cell development and activation. Lck-deficient mice show a pronounced thymic atrophy, with a dramatic reduction in the double-positive (CD4+CD8+) thymocyte population. Mature, single-positive thymocytes are not detectable in these mice and there are only very few peripheral T cells. These results illustrate the crucial role of this T-cell-specific tyrosine kinase in the thymocyte development. 相似文献
966.
F. Haverkate J. de Gier L. L. M. van Deenen 《Cellular and molecular life sciences : CMLS》1964,20(9):511-512
Zusammenfassung Der Gehalt an
3-trans-Hexadecensäure im Phosphatidylglycerol aus grünen Spinatblättern (Spinacea oleracea) erweist sich als auffallend hoch. Die enzymatische Hydrolyse zeigt die C16-Monoensäure mit der-Stelle des Phosphatids verknüpft. 相似文献
967.
H. van Cauwenberge J. Lecomte J. Goblet 《Cellular and molecular life sciences : CMLS》1954,10(1):30-31
Summary (1)—In the rat, total extracts of cortex, cortisone and A.C.T.H. do not retard the fixation of a vital colorant at the level of a cutaneous zone irritated by chloroform.(2)—Phenergan prolongs the delay in the appearance of the blue.(3)—Sodium salicylate selectively inhibits the inflammatory cutaneous action of chloroform, even after adrenalectomy. 相似文献
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