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101.
Summary Estrogen secretion during infancy may selectively enhance the phosphogluconate oxidative pathway in the rat uterus, for altered estrogen-stimulated glucose oxidation prepubertally is correlated (+0.91) with impaired ovarian development and not uterine estrogen receptor content.This work was supported in part by NSF Research Grant PCM-8409586. 相似文献
102.
Estrogen secretion during infancy may selectively enhance the phosphogluconate oxidative pathway in the rat uterus, for altered estrogen-stimulated glucose oxidation prepubertally is correlated (+0.91) with impaired ovarian development and not uterine estrogen receptor content. 相似文献
103.
104.
105.
Transgenic plant aequorin reports the effects of touch and cold-shock and elicitors on cytoplasmic calcium 总被引:91,自引:0,他引:91
Methods for measuring plant cytoplasmic calcium using microelectrodes or microinjected fluorescent dyes are associated with extensive technical problems, so measurements have been limited to single or small groups of cells in tissue strips or protoplasts. Aequorin is a calcium-sensitive luminescent protein from the coelenterate Aequorea victoria (A. forskalea) which is formed from apoaequorin, a polypeptide of relative molecular mass approximately 22,000, and coelenterazine, a hydrophobic luminophore. Microinjected aequorin has been widely used for intracellular calcium measurement in animal cells, but its use in plants has been limited to exceptionally large cells. We show here that aequorin can be reconstituted in transformed plants and that it reports calcium changes induced by touch, cold-shock and fungal elicitors. Reconstituted aequorin is cytoplasmic and nonperturbing; measurements can be made on whole plants and a calcium indicator can be constituted in every viable cell. Now that apoaequorin can be targeted to specific organelles, cells and tissues, with the range of coelenterazines with differing calcium sensitivities and properties available, this new method could be valuable for determining the role of calcium in intracellular signalling processes in plants. 相似文献
106.
A. Campbell M. K. Martin K. J. Farrington A. Erdelyi R. Johnston P. Sorby H. V. Whitlock I. G. Pearson R. C. Jones J. A. Haigh C. P. DeGoosh 《Cellular and molecular life sciences : CMLS》1967,23(12):992-993
Zusammenfassung 2-Acetoxy-4-chlor-3,5-dijodbenzanilid zeigte eine hohe Wirksamkeit gegen junge und gereifteF. hepatica andH. controtus in Schaften bei einer oralen Dosis von 25 und 40 mg/kg. Die gute Verträglichkeit der Verbindung in Schafen ergab sich aus Feldversuchen in Australien. 相似文献
107.
A. A. Adekunle T. C. Campbell S. C. Campbell 《Cellular and molecular life sciences : CMLS》1979,35(2):241-242
Summary Rat liver microsomes and homogenized mucosal linings prepared from vitamin A-supplemented and deficient male rats were used in metabolic studies of 7-3H-styrene oxide. The colon tissue in deficient animals exhibits a significantly higher value of Vmax than the same tissue from vitamin-supplemented animals. The implications of this finding in addition to our earlier observation10 is discussed in relation to colon carcinoma.Acknowledgments. This work was supported by USPHS (NIEHS) Grant RO1 ES 00336 and RO1 CA 00270 and funds from Hoffman-La Roche Foundation Research Corporation. 相似文献
108.
D. Campbell 《Cellular and molecular life sciences : CMLS》1957,13(8):327-328
Résumé Huit diurétiques mercuriels ont été étudiés selon la technique deSperber utilisant la circulation porte rénale de la poule. Six d'entre eux ont montrés clairement leur élimination par secrétion
tubulaire. Une diurèse acqueuse peut être obtenue avec tous les diuretiques étudiés, dans la plupart des cas elle est unilatérale
du c?té injecté. Une diurèse Na et Cl la suit. On peut supprimer la diurèse unilatérale par la probenécide et le vert de bromocrésol.
Les composés étudiés sont éliminés à des vitesses très différentes. Ceux qui présentent l'élimination la plus lente, montrent
également l'activité diurétique la plus grande et de plus longue durée.
相似文献
109.
Defective membrane repair in dysferlin-deficient muscular dystrophy 总被引:35,自引:0,他引:35
Bansal D Miyake K Vogel SS Groh S Chen CC Williamson R McNeil PL Campbell KP 《Nature》2003,423(6936):168-172
Muscular dystrophy includes a diverse group of inherited muscle diseases characterized by wasting and weakness of skeletal muscle. Mutations in dysferlin are linked to two clinically distinct muscle diseases, limb-girdle muscular dystrophy type 2B and Miyoshi myopathy, but the mechanism that leads to muscle degeneration is unknown. Dysferlin is a homologue of the Caenorhabditis elegans fer-1 gene, which mediates vesicle fusion to the plasma membrane in spermatids. Here we show that dysferlin-null mice maintain a functional dystrophin-glycoprotein complex but nevertheless develop a progressive muscular dystrophy. In normal muscle, membrane patches enriched in dysferlin can be detected in response to sarcolemma injuries. In contrast, there are sub-sarcolemmal accumulations of vesicles in dysferlin-null muscle. Membrane repair assays with a two-photon laser-scanning microscope demonstrated that wild-type muscle fibres efficiently reseal their sarcolemma in the presence of Ca2+. Interestingly, dysferlin-deficient muscle fibres are defective in Ca2+-dependent sarcolemma resealing. Membrane repair is therefore an active process in skeletal muscle fibres, and dysferlin has an essential role in this process. Our findings show that disruption of the muscle membrane repair machinery is responsible for dysferlin-deficient muscle degeneration, and highlight the importance of this basic cellular mechanism of membrane resealing in human disease. 相似文献
110.
Campbell G 《Nature》2002,418(6899):781-785
Arthropods and higher vertebrates both possess appendages, but these are morphologically distinct and the molecular mechanisms regulating patterning along their proximodistal axis (base to tip) are thought to be quite different. In Drosophila, gene expression along this axis is thought to be controlled primarily by a combination of transforming growth factor-beta (TGF-beta) and Wnt signalling from sources of ligands, Decapentaplegic (Dpp) and Wingless (Wg), in dorsal and ventral stripes, respectively. In vertebrates, however, proximodistal patterning is regulated by receptor tyrosine kinase (RTK) activity from a source of ligands, fibroblast growth factors (FGFs), at the tip of the limb bud. Here I revise our understanding of limb development in flies and show that the distal region is actually patterned by a distal-to-proximal gradient of RTK activity, established by a source of epidermal growth factor (EGF)-related ligands at the presumptive tip. This similarity between proximodistal patterning in vertebrates and flies supports previous suggestions of an evolutionary relationship between appendages/body-wall outgrowths in animals. 相似文献