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311.
An inflammatory response followed by vascular injury plays an important role in neointima formation and development of atherosclerotic lesions, which are in part mediated by proinflammatory cytokines. Using a cuff injury model, we examined the effects of adenovirus-mediated overexpression of phosphatase and tensin homology deleted on chromosome 10 (PTEN) on neointima formation and the proinflammatory response. A cuff was placed around the femoral artery, and adenovirus expressing human PTEN type 1 (AdPTEN) or Escherichia coli beta-galactosidase (AdLacZ) was injected between the cuff and the adventitia. After 14 days, the arteries were examined histopathologically and by Western blotting. The significant reduction of neointima formation by AdPTEN compared with AdLacZ was accompanied by reduced cell proliferation and increased adventitial cell apoptosis. AdPTEN also reduced expression of phosphorylated I kappa B-alpha, but not nonphosphorylated I kappa B-alpha. Western blotting revealed that AdPTEN reduced the cuff injury-induced expression levels of monocyte chemoattractant protein-1, TNF-alpha, and IL-1 beta and their expression in all layers of the arterial wall. In contrast, cuff-induced macrophage invasion, which was also inhibited by AdPTEN, was detected only at the intimal surface and in the adventitia. In cultured vascular smooth muscle cells, PTEN directly inhibited ANG II-induced monocyte chemoattractant protein-1 expression as quantified by real-time PCR and Western blotting. Our results suggest that overexpression of PTEN reduces neointima formation, possibly in part through inhibition of the inflammatory response by macrophage invasion and proinflammatory cytokine expression.  相似文献   
312.
PCR amplifications using primers for the clustered regularly interspaced short palindromic repeats (CRISPRs)-associated gene 1 (cas1), cas2, putative (p)-cas and CRISPRs genes generated cas1, cas2, p-cas and CRISPRs genes segments with 9–28 of 28 urease-positive thermophilic Campylobacter (UPTC) isolates, respectively. The p-cas and CRISPRs genes segments were amplified with 10 of 11 and 0 of 11 urease-negative (UN) Campylobacter lari isolates, respectively. When the nucleotide sequences of the CRISPRs consensus sequence repeats of each 33–37 base pairs from the 18 Campylobacter jejuni isolates were aligned, as well as from the four C. jejuni reference and UPTC CF89-12 strains, the repeats were identified as being almost identical. Although a total of all 18 C. jejuni isolates examined gave PCR-positive signals for the CRISPRs genes, it was, interestingly, suggested that many numbers of C. lari and C. jejuni isolates may possibly carry cas but not CRISPRs genes within their CRISPRs loci. In addition, PCR amplification by using a novel primer pair of f-ClCRISPR-ladder and ClCRISPRs-R, which were novel to this study, with the UPTC CF89-12 strain was shown to be useful for the detection of the putative CRISPRs separated by the non-repetitive unique spacer regions, with the electrophoretic ladder DNA profile following 5.0 % polyacrylamide gel electrophoresis. Secondary structure models of the CRISPRs repeats were predicted with UPTC CF89-12 and two C. jejuni strains.  相似文献   
313.
The environmental impact of agricultural waste from the processing of food and feed crops is an increasing concern worldwide. Concerted efforts are underway to develop sustainable practices for the disposal of residues from the processing of such crops as coffee, sugarcane, or corn. Coffee is crucial to the economies of many countries because its cultivation, processing, trading, and marketing provide employment for millions of people. In coffee-producing countries, improved technology for treatment of the significant amounts of coffee waste is critical to prevent ecological damage. This mini-review discusses a multi-stage biorefinery concept with the potential to convert waste produced at crop processing operations, such as coffee pulping stations, to valuable biofuels and bioproducts using biochemical and thermochemical conversion technologies. The initial bioconversion stage uses a mutant Kluyveromyces marxianus yeast strain to produce bioethanol from sugars. The resulting sugar-depleted solids (mostly protein) can be used in a second stage by the oleaginous yeast Yarrowia lipolytica to produce bio-based ammonia for fertilizer and are further degraded by Y. lipolytica proteases to peptides and free amino acids for animal feed. The lignocellulosic fraction can be ground and treated to release sugars for fermentation in a third stage by a recombinant cellulosic Saccharomyces cerevisiae, which can also be engineered to express valuable peptide products. The residual protein and lignin solids can be jet cooked and passed to a fourth-stage fermenter where Rhodotorula glutinis converts methane into isoprenoid intermediates. The residues can be combined and transferred into pyrocracking and hydroformylation reactions to convert ammonia, protein, isoprenes, lignins, and oils into renewable gas. Any remaining waste can be thermoconverted to biochar as a humus soil enhancer. The integration of multiple technologies for treatment of coffee waste has the potential to contribute to economic and environmental sustainability.  相似文献   
314.
GM2 gangliosidoses are autosomal recessive lysosomal storage diseases (LSDs) caused by mutations in the HEXA, HEXB and GM2A genes, which encode the human lysosomal β-hexosaminidase (Hex) α- and β-subunits, and GM2 activator protein (GM2A), respectively. These diseases are associated with excessive accumulation of GM2 ganglioside (GM2) in the brains of patients with neurological symptoms. Here we established a CHO cell line overexpressing human GM2A, and purified GM2A from the conditioned medium, which was taken up by fibroblasts derived from a patient with GM2A deficiency, and had the therapeutic effects of reducing the GM2 accumulated in fibroblasts when added to the culture medium. We also demonstrated for the first time that recombinant GM2A could enhance the replacement effect of human modified HexB (modB) with GM2-degrading activity, which is composed of homodimeric altered β-subunits containing a partial amino acid sequence of the α-subunit, including the GSEP loop necessary for binding to GM2A, on reduction of the GM2 accumulated in fibroblasts derived from a patient with Tay-Sachs disease, a HexA (αβ heterodimer) deficiency, caused by HEXA mutations. We predicted the same manner of binding of GM2A to the GSEP loop located in the modified HexB β-subunit to that in the native HexA α-subunit on the basis of the x-ray crystal structures. These findings suggest the effectiveness of combinational replacement therapy involving the human modified HexB and GM2A for GM2 gangliosidoses.  相似文献   
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316.
By using a pyroelectric detector constructed with a polyvinylidene fluoride film, a rapid rise in the temperature of the dark-adapted bullfrog retina induced by light was demonstrated. In the bullfrog retina, as in the squid retina examined previously, the heat generated in response to a brief light pulse was found to be far greater than the amount produced by conversion of the entire radiant energy of the stimulus into heat. The thermal responses consist of the heat generated by the photoreceptor and the postsynaptic elements in the retina, preceded by a small signal reflecting conversion of a portion of the radiant energy of the stimulus into heat. The dependence of the thermal responses on the light intensity, on the wavelength and on a variety of physical and chemical agents was examined. The exothermic process underlying the production of heat by the photoreceptor was found to precede the electrophysiological response of the retina.  相似文献   
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319.
Proteins in the squid giant axon were labeled with 32P by in vitro incubation of isolated axoplasm with radioactive [γ-32P]adenosine triphosphate (ATP) and separated by polyacrylamide sodium dodecyl sulfate gel electrophoresis. The two major phosphorylated regions on the gel had molecular weights of 400 000 and 200 000. These two peaks appear to be neurofilament proteins of squid axoplasm. The same set of proteins was phosphorylated in the axoplasm regardless of whether the [γ-32P]ATP was applied in situ intracellularly or extracelarly. These results suggest that ATP in the extracellular space is, by some ATP-translocation mechanism, utilized in the process of intracellular phosphorylation. Measurements of the apparent influx of ATP across the squid axon membrane yielded results consistent with the view that ATP in the extracellular fluid could be transported into the axoplasm.  相似文献   
320.
Journal of Plant Research - Seed and root hair protective protein (SRPP) is expressed in seeds and root hairs, localized in the cell wall, and involved in cell wall integrity. We analyzed a...  相似文献   
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