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721.
Regulation of Na,K-pump-mediated transport by prolactin in cultured human prostate epithelial cells.
M J Duran M Chosseler TA Pressley 《Cellular and molecular biology, including cyto-enzymology》2004,50(7):809-814
The prostate gland is unique in its ability to secrete large amounts of zinc and citrate, suggesting that it employs unusual transport mechanisms. Intracellular ionic homeostasis in prostate is likely to be mediated by the Na,K-pump, yet there have been few studies of its regulation in this tissue. Accordingly, we explored the expression of the Na,K-pump in PC3 cells, an established cell line of human prostate epithelial cells. Total RNA from confluent monolayers of PC3 cells was isolated, reverse transcribed, and the resulting complementary DNA was amplified by polymerase chain reaction using primers specific for each of the pump's constituent subunits. The amplification revealed a complex pattern of Na,K-pump expression, with detection of mRNAs encoding the alpha1-, alpha3-, alpha4-, betal-, beta2- and beta3-isoforms. We next examined the effect on pump activity of prolactin, an important mediator of cell proliferation in prostate cancer. Monolayers exposed to 10 nM prolactin for 24 hr revealed an inhibition of 40% in ouabain-sensitive 86Rb+ uptake, a sensitive measure of pump-mediated transport. These experiments suggest that the unique transport properties of prostate may depend, at least in part, on a complicated pattern of Na,K-pump expression and regulation. 相似文献
722.
Nobuaki Ito Shiro Tabata Shingo Kawahara Yoshinari Hirano Katsuko Nakajima Kazuto Uchida Tadaomi Hirota 《The Histochemical journal》1993,25(3):242-249
Summary Using immunostaining with monoclonal antibodies (mAbs) from three different sources as well as anti-B lectin, GSAI-B4 staining and -galactosidase digestion, blood group B antigens were localized and analysed in tissue sections of sublingual glands from blood group B and AB individuals. Quantitative analysis of galactose was simultaneously carried out on the supernatant enzyme solution used for treating tissue sections by high-performance liquid chromatography (HPLC). In addition, galactose liberated from the pancreas tissues of blood group B and AB individuals was also estimated by HPLC analysis in order to compare the content of antigens. mAb-B(H079) and GSAI-B4 reacted uniformly with the mucous cells from blood group B and AB secretors. On the other hand, other mAbs-B(B006 and A582) recognized the antigen in a limited number of cells or was even negative in some cases of blood group AB individuals. Only mAb-B(H079) recognized the B antigens in mucous cells from non-secretors. Digestion with -galactosidase resulted in the consistent appearance of H and Leb antigens in the mucous cells of all the secretors examined, although the reduction of staining intensity with anti-B reagents was not so marked. Ley antigens also appeared in some cases after the enzyme digestion. In non-secretors, Leb and Ley antigens, but not H antigens, appeared in some mucous cells following enzyme digestion. HPLC analysis of galactose revealed that -galactosidase can specifically liberate the terminal galactose residues of B antigens, and no marked difference was present in the content of liberated galactose from mucous cells of sublingual glands among the individuals investigated (8.5–11.7 nmoles cm–2). No galactose was detected in samples from the sublingual glands of non-secretors, and only a trace amount of galactose was detected in the samples from pancreas tissues. These results suggest that the observed difference in the reactivity of different reagents with each tissue site can be ascribed to both quantitative and qualitative heterogeneity of B antigens. 相似文献
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724.
A Physical Map of the Genome of a Unicellular Cyanobacterium Synechocystis sp. Strain PCC6803 总被引:1,自引:0,他引:1
Kotani Hirokazu; Kaneko Takakazu; Matsubayashi Toru; Sato Shusei; Sugiura Masahiro; Tabata Satoshi 《DNA research》1994,1(6):303-307
An accurate physical map of the genome of a cyanobacterium,Synechocystis sp. strain PCC6803, was constructed on the basisof restriction and linking clone analysis. The genome contained6 recognition sites for AscI, 25 sites for MluI, and 31 sitesfor SplI, and the entire genome size was estimated to be 3.6Mb. Sixteen genes or gene clusters, including those involvedin the photosynthetic systems, were localized on the physicalmapof the genome by hybridization. In the course of the above analysis,two extra chromosomal units with approximate sizes of 110 kband 125 kb were identified. 相似文献
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