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21.
Multiple sclerosis is a neurodegenerative disease characterized by the present of leukocytes in the brain tissue and subsequently the formation of sclerotic plaques. Leukocytes penetration into the blood–brain barrier is related to several factors, such as, the conversion of leukocyte gene expression or plasma characteristics. In this frame, we explore alteration of matrix metalloproteinase-2 (MMP-2), transforming growth factor beta (TGF-β) family, and Claudin-11 (as a main myelin structural protein) in leukocytes and blood plasma of multiple sclerosis patients compared to the normal group. Blood samples were collected from thirteen men affected by MS and fifteen healthy men. Leukocyte gene expression was measured using real-time PCR and plasma parameters were examined by ELISA. The results of this study showed that the gene expression of Claudin-11 was significantly higher in MS group compared with normal. Interestingly, the MMP-2 pattern was similar to Claudin-11 and correlated positively with it. It was observed that, although the expressions of TGF-β1 and TGF-β2 are down-regulated in the leukocytes of subjects with MS, they showed higher levels of these cytokines in blood plasma. The plasma level of TGF-β3 in MS patients was higher than normal and correlated with Claudin-11 concentration. In conclusion, the aberrant pattern of Claudin-11, TGF-βs family, and MMP-2 expression in leukocytes of the MS patients was observed in this study. Moreover, the plasma levels of TGF-βs family increased in the MS group. The findings of this study provide clues for further investigations to assay MS pathogenesis.  相似文献   
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The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains.  相似文献   
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Recently many researchers have proposed a protective role for morphine against tumor growth and metastasis, especially through induction of apoptosis in tumoral cells. These findings may lead to underestimation of cytotoxic effects of opioid drugs which are usually expected only at high doses. The present study was conducted to clarify whether repeated morphine administration, which is commonly used for relief from chronic pain, would interfere with liver antioxidant defence and hepatocytes vitality. Morphine was injected repeatedly at doses that have been reported to relieve cancer pain and reduce tumor spread in mice (5 and 10 mg/kg/day for nine consecutive days). The changes in hepatic glutathione concentration, its synthesis pathway and enzymatic antioxidant defense revealed the pro-oxidant effects of chronic morphine treatment on the liver. None of these changes were observed in those mice that were co-treated with naltrexone (opioid antagonist) and same doses of morphine. However induction of liver conjugating enzymes following morphine treatment was not receptor mediated. Moreover, chronic morphine treatment induced hepatocytes apoptosis. Interestingly, the apoptotic changes were antagonized by co-administration of either naltrexone or thiol antioxidant. In conclusion, although hepatotoxic effects of morphine at high doses have been reported previously, our findings propose that repeated morphine administration even at lower doses would induce oxidative stress in the liver, which may contribute to induction of apoptosis in hepatocytes. Since many of the observed adverse effects were mediated by opioid receptors, our results suggest that other opioid analgesics should also be used more cautiously.  相似文献   
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Present study investigates relationships between total and bioaccessibility of trace elements (Cd, Co, Cr, Cu, Mn, NI, Pb, V, and Zn) concentrations in sediment and their bioaccumulation in species in Shadegan wetland in southwest of Iran. Bioavailability factor (BAF) and translocation factor (TF) were calculated in plants and trophic transfer factor (TTF) was determined in bird species. For this purpose, sampling of sediments, aquatic plants including Phragmites australis, Typha australis, Scripus maritimus and two bird species encircling Porphyrio porphyrio and globally threatened Marmaronetta angustirostris were carried out during winter 2009. Result of chemical analysis show that bioaccessibility concentrations of Mn (8.31 mg/kg), V (1.33 mg/kg), and Pb (1.03 mg/kg) are higher than other metals. The uptake trend of trace elements in plant decreases as root > stem > leaf. Accumulation levels of trace elements in different tissues of P. porphyrio and M. angustirostris are almost identical and considerable. Accumulation and toxicity of Cd in birds is more than plants. In addition, BAF of V, Pb, and Cr indicates high accumulation by plants and great pollution rate in the area of study. In S. maritimus TF for Mn, Cu, Pb, and V are high whereas in T. australis, Cu and Pb posses the highest TF. Also Cr, Co, Mn, Ni, and Zn have higher TF from stem to leaf than root to stem in P. australis. Finally, TTFs were compared in various bird species.  相似文献   
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Urmia Lake is one of the most permanent hypersaline lakes in the world which is threatened by hypersalinity and serious dryness. In spite of its importance no paper has been published regarding bacterial community of this lake. Accordingly, the present study aimed to investigate the halophilic bacteria in the aforementioned lake. In so doing, thirty seven strains were isolated on six different culture media. The isolated strains were characterized using phenotypic and genotypic methods. Growth of the strains occurred at 25–35°C, pH 6–9 and 7 to 20% (w/v) NaCl indicating that most of the isolates were moderately halophiles. Catalase, oxidase and urease activities were found to be positive for the majority of the isolates. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolated bacteria belonged to two major taxa: Gammaproteobacteria (92%, including Salicola [46%], Pseudomonas [13.5%], Marinobacter [11%], Idiomarina [11%], and Halomonas [8%]) and Firmicutes (8%, including Bacillus [5%] and Halobacillus [3%]). In addition, a novel bacterium whose 16S rRNA gene sequence showed almost 98% sequence identity with the taxonomically troubled DSM 3050T, Halovibrio denitrificans HGD 3T and Halospina denitriflcans HGD 1–3, each, was isolated. 16S rRNA gene similarity levels along with phenotypic characteristics suggest that some of the isolated strains could be regarded as potential type strain for novel species, on which further studies are recommended.  相似文献   
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Statistics from the NHS Blood and Transplant Annual Review show that total organ transplants have increased to 4213 in 2012, while the number of people waiting to receive an organ rose to 7613 that same year. Human donors as the origin of transplanted organs no longer meet the ever-increasing demand, and so interest has shifted to synthetic organ genesis as a form of supply. This focus has given rise to new generation tissue and organ engineering, in the hope of one day designing 3D organs in vitro. While research in this field has been conducted for several decades, leading to the first synthetic trachea transplant in 2011, scaffold design for optimising complex tissue growth is still underexplored and underdeveloped. This is mostly the result of the complexity required in scaffolds, as they need to mimic the cells’ native extracellular matrix. This is an intricate nanostructured environment that provides cells with physical and chemical stimuli for optimum cell attachment, proliferation and differentiation. Carbon nanotubes are a popular addition to synthetic scaffolds and have already begun to revolutionise regenerative medicine. Discovered in 1991, these are traditionally used in various areas of engineering and technology; however, due to their excellent mechanical, chemical and electrical properties their potential is now being explored in areas of drug delivery, in vivo biosensor application and tissue engineering. The incorporation of CNTs into polymer scaffolds displays a variety of structural and chemical enhancements, some of which include: increased scaffold strength and flexibility, improved biocompatibility, reduction in cancerous cell division, induction of angiogenesis, reduced thrombosis, and manipulation of gene expression in developing cells. Moreover CNTs’ tensile properties open doors for dynamic scaffold design, while their thermal and electrical properties provide opportunities for the development of neural, bone and cardiac tissue constructs.  相似文献   
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Background

Tolerance to the analgesic effect of opioids is a pharmacological phenomenon that occurs after their prolonged administration. It has been shown that morphine-induced tolerance is associated with apoptosis in the central nervous system and neuroprotective agents which prevented apoptosis signaling could attenuate tolerance to the analgesic effects. On the other hand donepezil, an acetylcholinesterase inhibitor, has been reported to have neuroprotective effects. Therefore in this study, the effect of systemic administration of donepezil on morphine-induced tolerance and apoptosis in the rat cerebral cortex and lumbar spinal cord was evaluated. Various groups of rats received morphine (ip) and different doses of donepezil (0, 0.5, 1, 1.5 mg/kg/day). Nociception was assessed using tail flick apparatus. Tail flick latency was recorded when the rat shook its tail. For apoptosis assay other groups of rats received the above treatment and apoptosis was evaluated by in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method.

Results

The results showed that administration of donepezil (0.5, 1, 1.5 mg/kg, ip) delayed the morphine tolerance for 9, 12 and 17 days, respectively. Furthermore pretreatment injection of donepezil attenuated the number of apoptotic cells in the cerebral cortex and lumbar spinal cord compared to the control group.

Conclusion

In conclusion, we found that systemic administration of donepezil attenuated morphine-induced tolerance and apoptosis in the rat cerebral cortex and lumbar spinal cord.  相似文献   
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