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51.
Critical discussions among some in Palestinian studies describe foreign involvement in NGO development in the Occupied Territories since the 1990s as having been detrimental to Palestinian collective aspirations, and even a tool of imperialism. In the 1970s and 1980s, Palestinians in the West Bank and Gaza Strip mobilized their own civilian organizations to build an infrastructure of resistance to the Israeli Occupation that gave birth to the Intifada Uprising in December 1987. Foreign governments and organizations were drawn to their struggle and in the 1990s billions of dollars of foreign aid from more than 40 nations and over two dozen multilateral organizations flowed through hundreds of local and foreign NGOs. But this investment in the “peace process” did not stop a worsening occupation, and a second al Aqsa Intifada began in the fall 2000. Palestinian civil society suffered crippling blows and foreign actors were reduced to disaster relief and harm reduction. This article presents three ethnographic portraits from 1992, 1995 and 2002, that examine these changes in Palestinian civil society and the scholarly criticisms of foreign involvement. This article argues that such involvement could put Palestinian participants in a dangerous in-between social position, but that these positions of contradiction are often preferable to the destruction of militarism.  相似文献   
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Proteomic profiling with SELDI-TOF MS has facilitated the discovery of disease-specific protein profiles. However, multicenter studies are often hindered by the logistics required for prompt deep-freezing of samples in liquid nitrogen or dry ice within the clinic setting prior to shipping. We report high concordance between MS profiles within sets of quadruplicate split urine and serum samples deep-frozen at 0, 2, 6, and 24 h after sample collection. Gage R&R results confirm that deep-freezing times are not a statistically significant source of SELDI-TOF MS variability for either blood or urine.  相似文献   
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Protein kinase C (PKC) encodes a family of enzymes implicated in cellular differentiation, growth control, and tumor promotion. However, very little is known with respect to the molecular mechanisms that link protein kinase C to cell cycle control. Here we report that PKCeta associates with the cyclin E/Cdk2 complex. This is shown for the ectopically overexpressed PKCeta in NIH-3T3 cells, the inducibly expressed PKCeta in MCF-7 cells (under control of the tetracycline-responsive promoter), and the endogenously expressed PKCeta in mouse mammary epithelial HC11 cells. Subcellular cell fractionation experiments revealed that the complex with cyclin E is formed mostly in the nuclear fractions, although in these cells PKCeta is predominantly expressed in the cytosolic fractions. The complex of PKCeta and cyclin E was studied at various phases of the cell cycle, in serum-starved quiescent cells and in cells stimulated with serum to reenter the cell cycle. Interestingly, the interaction between PKCeta and cyclin E was most prominent in serum-starved cells and was disintegrated when cells entered the cells cycle. Immunofluorescence staining demonstrated that in serum-starved cells PKCeta is concentrated at the perinuclear zone, which is also the site of its colocalization with cyclin E. Colocalization of PKCeta and cyclin E in the perinuclear region was observed in serum-starved cells, and less in proliferating cells. These experiments suggest that the interaction between PKCeta and cyclin E is carefully regulated, and is correlated with the inactivated form of the cyclin E/Cdk2 complex. Thus, our studies support an important link between PKC and cell cycle control.  相似文献   
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Membrane proteins and water-soluble proteins share a similar core. This similarity suggests that it should be possible to water-solubilize membrane proteins by mutating only their lipid-exposed residues. We have developed computational tools to design water-soluble variants of helical membrane proteins, using the pentameric phospholamban (PLB) as our test case. To water-solublize PLB, the membrane-exposed positions were changed to polar or charged amino acids, while the putative core was left unaltered. We generated water-soluble phospholamban (WSPLB), and compared its properties to its predecessor PLB. In aqueous solution, WSPLB mimics all of the reported properties of PLB including oligomerization state, helical structure, and stabilization upon phosphorylation. We also characterized the truncated mutant WSPLB (21-52) comprising only the former transmembrane segment of PLB. This peptide shows a decreased specificity for forming a pentameric oligomerization state.  相似文献   
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In recent studies, induction of the heat shock response increased IL-6 production in gut mucosa in vivo and in cultured Caco-2 cells in vitro. The heat shock response is associated with increased survival of cells exposed to otherwise lethal hyperthermia, so called thermotolerance, but the role of IL-6 in the induction of thermotolerance is not known. We tested the hypothesis that treatment of cultured Caco-2 cells with IL-6 results in the development of thermotolerance. Cells were treated with human recombinant IL-6 for 1h followed by 3 h recovery in cytokine-free medium whereafter cells were exposed to heat stress (48 degrees C for 2 h). In untreated cells, the heat stress resulted in an approximately 80% cell death. In cells treated with IL-6, cell viability after heat stress was significantly improved and was doubled at an IL-6 concentration of 20 ng/ml. Treatment of the cells with other cytokines (IL-4, IL-10, IL-1beta, or TNFalpha) did not induce thermotolerance, suggesting that the effect of IL-6 may be specific for this cytokine. The induction of thermotolerance by IL-6 was blocked by an IL-6 receptor antibody, suggesting that the development of thermotolerance was receptor-mediated. Treatment of cells with IL-6 did not induce an heat shock response as suggested by unaltered heat shock protein 70 and 90 levels and unaffected heat shock factor DNA binding activity. In addition, the IL-6-induced thermotolerance was not inhibited by quercetin. The present study provides the first evidence of IL-6-induced thermotolerance and suggests that this effect of IL-6 is independent of the heat shock response.  相似文献   
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D G Cornell  E Avram  N Filipescu 《Steroids》1979,33(5):485-494
Irradiation of testosterone, 4-androstene-3,17-dione, or their "half-molecule" 4,4a,5,6,7,8-hexahydro-4a-methyl-2(3H)-naphthalenone in dilute aqueous solutions with ultraviolet light of 254 nm wavelength caused rapid addition of water across the olefinic bond with formation of 5,17 beta-dihydroxy-5 alpha-androstan-3-one, 5-hydroxy-5 alpha-androstane-3-17-dione, and 9-hydroxy-10-methyl-2-decalone, respectively. Time-lapse spectrometry in the ultraviolet region showed that the photohydration of the androgenic steroids was extremely efficient and virtually free of the side reactions. Preparative photolytic reactions carried out in water-methanol solutions allowed isolation and characterization of photoproducts.  相似文献   
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