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71.
As a critical stage of pregnancy, the implantation of blastocysts into the endometrium is a progressive, excessively regulated local tissue remodeling step involving a complex sequence of genetic and cellular interplay executed within an optimal time frame. For better understanding the causes of infertility and, more importantly, for developing powerful strategies for successful implantations and combating infertility, an increasing number of recent studies have been focused on the identification and study of newly described substances in the reproductive tree. The endothelins (ET), a 21-aminoacidic family of genes, have been reported to be responsible for the contraction of vascular and nonvascular smooth muscles, including the smooth muscles of the uterus. Therefore, this review aims to comprehensively discuss the physiological role of endothelins and signaling through their receptors, as well as their probable involvement in the implantation process.  相似文献   
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73.
Molecular Biology Reports - Cardiovascular diseases (CVDs) are the most common and the first cause of death worldwide. While some studies have investigated the association of the Adenosine...  相似文献   
74.
Oxidized l-alpha-1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (OxPAPC), a component of minimally modified LDL, induces production of proinflammatory cytokines and development of atherosclerotic lesions. We tested the hypothesis that OxPAPC alters expression, phosphorylation, and localization of tight junction (TJ) proteins, particularly occludin, a transmembrane TJ protein. OxPAPC reduced total occludin protein and increased occludin phosphorylation dose dependently (10-50 microg/ml) and time dependently in bovine aortic endothelial cells. OxPAPC decreased occludin mRNA and reduced the immunoreactivity of zonula occludens-1 at the cell-cell contacts. Furthermore, OxPAPC increased the diffusive flux of 10-kDa dextran in a dose-dependent manner. O2-* production by bovine aortic endothelial cells increased nearly twofold after exposure to OxPAPC. Also, enzymatic generation of O2-* by xanthine oxidase-lumazine and H2O2 by glucose oxidase-glucose increased occludin phosphorylation, implicating reactive oxygen species as modulators of the OxPAPC effects on occludin phosphorylation. Superoxide dismutase and/or catalase blocked the effects of OxPAPC on occludin protein content and phosphorylation, occludin mRNA, zonula occludens-1 immunoreactivity, and diffusive flux of 10-kDa dextran. These findings suggest that changes in TJ proteins are potential mechanisms by which OxPAPC compromises the barrier properties of the vascular endothelium. OxPAPC-induced disruption of TJs, which likely facilitates transmigration of LDL and inflammatory cells into the subendothelial layers, may be mediated by reactive oxygen species.  相似文献   
75.
Within arterial bifurcations or branching points, oscillatory shear stress (OSS) induces oxidative stress mainly via the reduced nicotinamide adenine dinucleodtide phosphate (NADPH) oxidase system. It is unknown whether 17beta-estradiol (E(2)) can regulate OSS-mediated low-density lipoprotein (LDL) modifications. Bovine aortic endothelial cells were pretreated with E(2) at 5 nmol/L, followed by exposure to OSS (0 +/- 3.0 dynes/cm(2) s and 60 cycles/min) in a flow system. E(2) decreased OSS-mediated NADPH oxidase mRNA expression, and E(2)-mediated (.-)NO production was mitigated by the NO synthase inhibitor N(G)-nitro-l-argenine methyl ester. The rates of O(2)(-.) production in response to OSS increased steadily as determined by superoxide-dismutase-inhibited ferricytochrome c reduction; whereas, pretreatment with E(2) decreased OSS-mediated O(2)(-.) production (n = 4, p < 0.05). In the presence of native LDL (50 microg/mL), E(2) also significantly reversed OSS-mediated LDL oxidation as determined by high-performance liquid chromatography. In the presence of O(2)(-.) donor, xanthine oxidase (XO), E(2) further reversed XO-induced LDL lipid peroxidation (n = 3, p < 0.001). Mass spectra acquired in the m/z 400-1800 range, revealed XO-mediated LDL protein nitration involving tyrosine 2535 in the alpha-2 domains, whereas pretreatment with E(2) reversed nitration, as supported by the changes in nitrotyrosine intensities. Thus, E(2) plays an indirect antioxidative role. In addition to upregulation of endothelial (.-)NO synthase and downregulation of Nox4 expression, E(2) influences LDL modifications via lipid peroxidation and protein nitration.  相似文献   
76.
Vascular factors beside metabolic problems are involved in both etiopathogenesis of diabetic neuropathy, and more remarkably, later in “repair” phase, that governs the net balance between neuro-regenerative/degenerative reactions. Regarding ischemic nature of diabetic neuropathy that highlights necessity of blood vessels re-establishment during tissue healing, VEGF (vascular endothelial growth factor) has been recently the subject of extensive investigations in diabetic neuropathy (DNU). This growth factor possesses angiogenic potentials in addition to the hemodynamic functions. The distribution of VEGF gene polymorphisms at positions −7*C/T, −1001*G/C, −1154*G/A and −2578*C/A were analysed by ARMS–PCR in 248 type 1 diabetic British-Caucasian subjects (81 DNU+, 167 DNU−). We have found that distribution of a VEGF gene polymorphism at promoter region (−7*C/T) was significantly different between diabetic subjects with vs. without neuropathy and the allele (C) conferred susceptibility to DNU (P = 0.02; OR = 1.78, 95% CI 1.0–3.1). The present study indicates that polymorphism of the VEGF gene at position −7*C/T might be implicated in the pathogenesis of diabetic neuropathy as it may harbour some functional/regulatory potential in VEGF gene expression. However, this requires further studies in order to better understand its phenotypic impact and to investigate the prognostic value of this polymorphism in diabetic neuropathy as a chronic complication of diabetes.  相似文献   
77.
Physiology and Molecular Biology of Plants - To study the possibility of increasing the drought tolerance of common bean with the exogenous application of 24-epibrassinolide (EBL), an experiment...  相似文献   
78.
Key message

Over-expression of CAX3 encoding a cation/proton exchanger enhances Cd tolerance by decreasing ROS (Reactive Oxygen Species) through activating anti-oxidative enzymes via elevation of Ca level in Arabidopsis

Abstract

CAXs (cation/proton exchangers) are involved in the sequestration of cations such as Mn, Li, and Cd, as well as Ca, from cytosol into the vacuole using proton gradients. In addition, it has been reported that CAX1, 2 and 4 are involved in Cd tolerance. Interestingly, it has been reported that CAX3 expressions were enhanced by Cd in Cd-tolerant transgenic plants expressing Hb1 (hemoglobin 1) or UBC1 (Ub-conjugating enzyme 1). Therefore, to investigate whether CAX3 plays a role in increasing Cd tolerance, CAX3 of Arabidopsis and tobacco were over-expressed in Arabidopsis thaliana. Compared to control plants, both transgenic plants displayed an increase in Cd tolerance, no change in Cd accumulation, and enhanced Ca levels. In support of these, AtCAX3-Arabidopsis showed no change in expressions of Cd transporters, but reduced expressions of Ca exporters and lower rate of Ca efflux. By contrast, atcax3 knockout Arabidopsis exhibited a reduced Cd tolerance, while the Cd level was not altered. The expression of Δ90-AtCAX3 (deletion of autoinhibitory domain) increased Cd and Ca tolerance in yeast, while AtCAX3 expression did not. Interestingly, less accumulation of ROS (H2O2 and O2?) was observed in CAX3-expressing transgenic plants and was accompanied with higher antioxidant enzyme activities (SOD, CAT, GR). Taken together, CAX3 over-expression may enhance Cd tolerance by decreasing Cd-induced ROS production by activating antioxidant enzymes and by intervening the positive feedback circuit between ROS generation and Cd-induced spikes of cytoplasmic Ca.

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79.

Isocyanide-based consecutive Bargellini/Ugi multicomponent reactions as a combinatorial strategy have been developed for the synthesis of new class of pseudo-peptides. Via Bargellini reaction 3-carboxamido-isobutyric acids are prepared using acetone, chloroform, sodium hydroxide, and isocyanides. Then, using Ugi multicomponent reaction strategy, pseudo-peptides containing three amide bonds are synthesized using the Bargellini reaction product, aldehydes, amines, and isocyanides. This is an efficient and eco-friendly approach for easy access to wide variety of structurally diverse, drug-like pseudo-peptides from cheap and readily available precursors in high yields.

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80.
Plant Molecular Biology Reporter - The aim of this study was to investigate the effects of drought stress on oxidative damage and efficiency of PSII photochemistry in barley and compare the...  相似文献   
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