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Recent evidence that excessive lipid accumulation can decrease cellular levels of autophagy and that autophagy regulates immune responsiveness suggested that impaired macrophage autophagy may promote the increased innate immune activation that underlies obesity. Primary bone marrow-derived macrophages (BMDM) and peritoneal macrophages from high-fat diet (HFD)-fed mice had decreased levels of autophagic flux indicating a generalized impairment of macrophage autophagy in obese mice. To assess the effects of decreased macrophage autophagy on inflammation, mice with a Lyz2-Cre-mediated knockout of Atg5 in macrophages were fed a HFD and treated with low-dose lipopolysaccharide (LPS). Knockout mice developed systemic and hepatic inflammation with HFD feeding and LPS. This effect was liver specific as knockout mice did not have increased adipose tissue inflammation. The mechanism by which the loss of autophagy promoted inflammation was through the regulation of macrophage polarization. BMDM and Kupffer cells from knockout mice exhibited abnormalities in polarization with both increased proinflammatory M1 and decreased anti-inflammatory M2 polarization as determined by measures of genes and proteins. The heightened hepatic inflammatory response in HFD-fed, LPS-treated knockout mice led to liver injury without affecting steatosis. These findings demonstrate that autophagy has a critical regulatory function in macrophage polarization that downregulates inflammation. Defects in macrophage autophagy may underlie inflammatory disease states such as the decrease in macrophage autophagy with obesity that leads to hepatic inflammation and the progression to liver injury.  相似文献   
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Paraoxonase (PON), a high-density lipoprotein-associated enzyme, is believed to protect against low-density lipoprotein oxidation and thus affects the risk of coronary artery disease (CAD). Three polymorphisms in the PON1 (Leu55Met and Gln192Arg) and PON2 (Ser311Cys) genes have been shown to be associated with the risk of CAD in several European or European-derived populations. In the present study, we examined the associations between these three markers and the severity of CAD as determined by the number of diseased coronary artery vessels in 711 subjects (589 whites and 122 blacks) from the Women's Ischemia Syndrome Evaluation (WISE) study. WISE is a National Heart, Lung, and Blood Institute-sponsored multicenter study designed to address issues related to ischemic-heart-disease recognition and diagnosis in women. Subjects were classified as having normal/minimal CAD (<20% stenosis), mild CAD (20%-49% stenosis), and significant CAD (>/=50% stenosis). The women who had >/=50% stenosis were further classified into groups with one-, two-, or three-vessel disease if any of the three coronary arteries had diameter stenosis >/=50%. No significant association was found between the PON polymorphisms and stenosis severity in either white or black women. However, among white women, when data were stratified by the number of diseased vessels, the frequency of the PON1 codon 192 Arg/Arg genotype was significantly higher in the group with three-vessel disease than in the other groups (those with one-vessel and two-vessel disease) combined (17.02% vs. 4.58%; P=.0066). Similarly, the frequency of the PON2 codon 311 Cys/Cys genotype was significantly higher in the group with three-vessel disease than in the other groups combined (15.22% vs. 4.61%; P=.018). The adjusted odds ratios for the development of three-vessel disease were 2.80 (95% confidence interval 1.06-7.37; P=.038) for PON1 codon 192 Arg/Arg and 3.68 (95% confidence interval 1.26-10.68; P=.017) for PON2 codon 311 Cys/Cys. Our data indicate that the severity of CAD, in terms of the number of diseased vessels, may be affected by common genetic variation in the PON gene cluster, on chromosome 7.  相似文献   
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An acidic glycolipid antigen that reacts with monoclonal IgM in patients with demyelinating neuropathy and with the mouse monoclonal antibody, HNK-1, was purified from human peripheral nerves. This lipid sharing antigenic determinants with the myelin-associated glycoprotein was shown to be an unusual glucuronic acid-containing sulfated glycosphingolipid with five sugars, but without sialic acid. Mild acid methanolysis converted the GlcUA to its methyl ester, removed the acidic sulfate group and abolished the antigenicity. Results from chemical, enzymatic, infrared, and mass spectral analysis suggested the following structure with a sulfate in a position that remains to be determined: GlcUA beta 1----3Gal beta 1----4GlcNAc beta 1----3Gal beta 1----4Glc beta 1----1 ceramide.  相似文献   
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The 13C-NMR spectra of nine naturally occurring CC linked biflavanoids have been assigned. The signals for the carbon atoms I-6, I-8, II-6, and II-8 appear in the region 90.0 ppm to 105.0 ppm. On the basis of the chemical shifts of these signals and their multiplicities in the off-resonance spectra, it is possible to determine the interflavonoid linkage in biflavanoids, provided that the A ring is involved. The level of oxidation of the ring C can be readily determined by a consideration of the chemical shift value of the carbonyl resonances. The position of the methoxyl substitution can also be inferred.  相似文献   
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Copper nanoparticles have enhanced the germination and wheat development. To explain the effects of copper nanoparticles on shoot of Pakistan-13 and NARC-11, proteomic technique was used. The physiological responses such as weights/lengths of seedling, shoot, and root of wheat varieties were increased on 10-ppm copper nanoparticle exposure. The number of proteins related to protein metabolism was increased in Pakistan-13 while protein metabolism and photosynthesis-related proteins were increased in NARC-11, treated with copper nanoparticles compared to untreated plants. Abundance of proteins related to glycolysis and tricarboxylic acid cycle was increased on copper nanoparticle exposure in Pakistan-13 and NARC-11. However, the abundance of proteins related to photosynthesis and tetrapyrole synthesis was decreased on copper nanoparticle exposure in Pakistan-13 and NARC-11. Chlorophyll content such as chlorophyll a, chlorophyll b, and total chlorophyll was decreased on copper nanoparticle exposure in Pakistan-13 and NARC-11. The rate of photosynthesis and carbon assimilation decreased on copper nanoparticle exposure. These results suggest that copper nanoparticles mend the seedling growth of wheat, which might be concomitant with the enhancement of protein abundance related to glycolysis and tricarboxylic acid cycle in wheat varieties.  相似文献   
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Eight biflavones have been isolated from the leaf extracts of Araucaria excelsa. 7″-O-Methylamento-flavone, 7,7″-di-O-methylamentoflavone, 4′ or 4″', 7-di-O-methylcupressuflavone, 7,7″,4″'-tri-O-methyl agathisflavone and 7,4′,7″-tri-O-methylamentoflavone are new compounds and are being reported for the first time. The others are 7,7″-di-O-methylagathisflavone,7,4′,7″,4″'-tetra-O-methylamentoflavone and 7,4′,7″,4″'-tetra-O-methyl-cupressuflavone. Mass and NMR spectral studies are used for structural elucidation. In addition, the presence of several other biflavones has been indicated by TLC examination of methylated products.  相似文献   
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