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991.
AIM: To explore the effect of protein kinase D1 (PKD1) on promoting angiogenesis in vitro and in vivo, and to furnish a new idea on targeting PKD1 for the treatment of ischemic heart disease such as myocardial infarction. METHODS: The culture, isolation and identification of endothelial progenitor cells (EPCs) were performed in vitro. The effects of PKD1 and its specific blocking agent CID755673 on expression levels of vascular endothelial growth factor (VEGF) and kinase insert domain receptor (KDR) in EPCs were determined. The rat model of myocardial infarction was established, the intervention effects of PKD1 and CID755673 on morphology, changes of microvessels and endothelial cells, and the expression of VEGF and KDR in the impaired myocardial tissue were analyzed. RESULTS: PKD1 significantly upregulated the expression of VEGF and KDR in EPCs in vitro. Meanwhile, the structure of myocardial tissue was more regular and clear, the cytomembrane of endothelial cells were more smooth and integrity, the pericytes were visible, and the expression of VEGF and KDR was significantly increased in PKD1 treatment group in vivo.CONCLUSION: PKD1 has the ability of angiogenesis obviously, which might be mediated by VEGF.  相似文献   
992.
AIM: To investigate the behavior of depression in chronic alcoholism and withdrawal model of mice, and to explore the co-mechanism of alcoholism and depression. METHODS: A novel model of chronic alcoholism was constructed in this study. The animals were divided into normal control group, and alcohol 7 d, 14 d, 21 d and 28 d groups. The mice were given alcohol preference test on the 6th, 13th, 20th and 27th days. After the test, alcohol were withdrawn for 1 d, then the next day the mice were given behavior test of depression. After the test, the mice were sacrificed. The contents of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) were detected by HPLC. The expression of cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) was detected by Western blot. RESULTS: The mice showed an obvious drinking phenomenon, and the immobility time of forced swimming test and tail suspension test was significantly increased, with increasing drinking days and withdrawal times. 5-HT level in 7 d group mice only increased in frontal cortex (P < 0.05). However, compared with control group, 5-HT levels in hippocampus and cortex were decreased on the 21th and 28th days (P < 0.01). NE levels in 21 d and 28 d groups were decreased in hippocampus and frontal cortex (P < 0.05), and no significant change was observed in 7 d and 14 d groups. The protein levels of p-CREB and BDNF were significantly decreased in hippocampus and frontal cortex of 12 d and 28 d groups (P < 0.05), and no significant change was observed in 7 d group and 14 d group. CONCLUSION: The co-mechanism of alcoholism, withdrawal and depression is related to 5-HT. 5-HT-cAMP-CREB-BDNF signaling pathway may be a common mechanism for alcoholism and depression.  相似文献   
993.
AIM: To explore the effects of curcumin analogue L6H4 on the myocardial tissue of type 2 diabetic rats and its mechanism. METHODS: Male Sprague-Dawley rats were randomly divided into normal control (NC) group, high-fat (HF) group, high-fat treatment (FT) group, diabetes mellitus (DM) group and diabetes treatment (DT) group.The rats in the latter 4 groups were fed high-fat diet for 4 weeks, then the rats in DM groups and DT groups were intraperitoneally injected with streptozotocin (STZ) to induce type 2 diabetes, while the rats in FT group and DT group were given L6H4. The blood glucose and lipid levels were detected by biochemical method, and serum adiponectin (APN) levels were detected by ELISA. The serum insulin levels were measured by radioimmunoassay and homeostasis model assessment of insulin resistance (HOMA-IR) were calculated. The morphological changes of myocardium were observed by Masson staining and electron microscopy. The protein expression of adiponectin receptor 1 (AdipoR1) and transforming growth factor β1(TGF-β1) in myocardial tissue were determined by immunohistochemistry. The protein expression of adipoR1 was also detected by Western blot for verification. RESULTS: Compared with NC group, the blood glucose, lipids, insulin, HOMA-IR and TGF-β1 were increased in HF and DM group, but they were decreased after treated with L6H4. Compared with NC group, the concentration of serum APN were decreased and the expression of AdipoR1 in the myocardium were weakened in HF group and DM group, and they increased after treated with L6H4. The myocardial fibrosis was obvious in HF group and DM group, the mitochondria in cardiomyocytes expanded, and the cristae disordered, partial disappeared. These lesions were significantly reduced after L6H4 treatment. CONCLUSION: L6H4 exerts a protective effect on the heart in type 2 diabetic rats. The increased concentration of serum APN, the enhanced expression of AdipoR1, and the expression of TGF-β1 inhibited by APN may be involved in the mechanism of protection.  相似文献   
994.
AIM: To investigate the effect of apyrase on the experimental silicosis. METHODS: C57BL/6 male mice were randomly divided into control group, silica treatment group, silica+apyrase group and silica+NS group. A mouse model of lung fibrosis was induced by crystalline silica particles (50 mg/kg, via oropharyngeal instillation), and were sacrificed at 3 h, 7 d, 14 d and 28 d. Apyrase was delivered by oropharyngeal aspiration at the same time and 4 h after silica challenge. The lung indexes were calculated and the concentration of ATP was detected by bioluminescent assay. The mRNA expression levels of collagen type Ⅰ(Col Ⅰ), collagen type Ⅲ (Col Ⅲ) and transforming growth factor β1 (TGF-β1) were examined by real-time PCR. The protein levels of TGF-β1 in bronchoalveolar lavage fluid were measured by ELISA. RESULTS: The elevated lung index and collagen levels showed that silicosis model was established successfully. Compared with silica group, apyrase treatment significantly alleviated silica-induced inflammation, reduced inflammation score on day 7, and decreased the lung index, collagen volume fraction and the mRNA expression of Col Ⅰand Col Ⅲ on day 28. Treatment with apyrase effectively down-regulated the mRNA levels of TGF-β1 in the lung tissues and TGF-β1 protein levels in bronchoalveolar lavage fluid on day 7.CONCLUSION: Apyrase attenuates the pulmonary inflammation and fibrosis of silicosis, which may be related with down-regulation of ATP and TGF-β1 in the lung tissues.  相似文献   
995.
AIM: To investigate the effects of tumor necrosis factor (TNF) receptor associated factor 3 (TRAF3) on the signaling pathway of NF-κB and the expression of Bax and Bid in renal collecting duct epithelial cells of polycystic kidney disease (PKD), and to observe the tubulogenesis of TRAF3 transgenics for exploring the protective effect of TRAF3 on the cystogenesis and development of PKD. METHODS: The signaling changes of NF-κB and expression of Bax and Bid in PKD renal collecting duct epithelial cells and TRAF3 transgenic PKD renal collecting duct epithelial cells were determined by the Western blot. The percentage of apoptotic cells was measured by flow cytometry with Annexin V staining. The caspase-3 activity was also measured. The 3D Matrigel culture was performed to examine abnormal tubulomorphogenesis in vitro. RESULTS: The over-expression of TRAF3 significantly inhibited the signaling pathway of NF-κB in PKD renal collecting duct epithelial cells and significantly downregulated the expression of Bax and Bid, and also decreased the cell apoptosis. More branch structures were observed in the TRAF3 transgenic PKD renal collecting duct epithelial cells. CONCLUSION: TRAF3 is a negative regulatory inhibitor for Bax and Bid by regulating the NF-κB signaling and may be a new target for inhibiting the cyst formation in PKD.  相似文献   
996.
在西苏旗对蒙古冰草的种子产量及产量构成因子进行了分析得出结果为冰草的实际种子产量与潜在种子产量差别很大,蒙古冰草种子产量的主要限制因子为抽穗率和结实率。  相似文献   
997.
Time series of commercial landings from the Algarve (southern Portugal) from 1982 to 1999 were analyzed using min/max autocorrelation factor analysis (MAFA) and dynamic factor analysis (DFA). These techniques were used to identify trends and explore the relationships between the response variables (annual landings of 12 species) and explanatory variables [sea surface temperature, rainfall, an upwelling index, Guadiana river (south‐east Portugal) flow, the North Atlantic oscillation, the number of licensed fishing vessels and the number of commercial fishermen]. Landings were more highly correlated with non‐lagged environmental variables and in particular with Guadiana river flow. Both techniques gave coherent results, with the most important trend being a steady decline over time. A DFA model with two explanatory variables (Guadiana river flow and number of fishermen) and three common trends (smoothing functions over time) gave good fits to 10 of the 12 species. Results of other models indicated that river flow is the more important explanatory variable in this model. Changes in the mean flow and discharge regime of the Guadiana river resulting from the construction of the Alqueva dam, completed in 2002, are therefore likely to have a significant and deleterious impact on Algarve fisheries landings.  相似文献   
998.
从分析新疆土地利用变化区域差异入手,运用模糊综合评判法对新疆土地利用区域变化影响因素进行定量分析,并在此基础上对新疆各区土地资源合理利用提出相应的建议和对策。  相似文献   
999.
采用实证分析和规范分析相结合的方法来研究影响物流行业上市公司资本结构的内外因素,并提出相应的对策与建议,以期能为物流行业上市公司制定合理的资本结构提供实证数据和参考。  相似文献   
1000.
J172等5个柳树良种育苗试验   总被引:3,自引:0,他引:3  
通过对5个柳树良种在不同类型区的扦插育苗试验,分析苗木生长量、生长季土壤含水量、土壤温度,结果表明:①各参试因素对生长量影响的程度依次为品种(系)>类型区>覆膜>扦插方法,因此在柳树壮苗培育中,应首先考虑优良品种的选择。②在不同类型区内,影响树木生长的主导生态因子亦不同。在高寒湿润区,热量是影响生长量的主导生态因子,故其覆用地膜的效果十分显著,其生长量较对照提高28.6%;在川塬区,土壤水肥是影响生长量的主导生态因子,故其覆用地膜的效果不太显著,应着重加强土壤水肥管理。  相似文献   
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