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991.
AIM:To study the effect of VEGF on extracellular H2O2 production in HUVECs and the role of H2O2 in the VEGF-induced proliferation. METHODS:HUVECs was stimulated with 500 μg/L VEGF. Products of extracellular H2O2 was detected by H2DCFDA staining. MTT method was used to value the influences of 3×106 U/L catalase and 5-20 mmol/L H2O2 to VEGF function. RESULTS:After treatment for 15 min with VEGF, HUVECs appeared fluorescence, and continued to become stronger, peaked at 45 min then decreased. HUVECs, which was treated simultaneity with VEGF and 3×106 U/L catalase, only appeared very faint fluorescence. The proliferation of HUVECs by VEGF was restrained when treated with 3×106 U/L catalase. The extrinsic H2O2 at concentration of 5-10 mmol/L promoted the proliferation of HUVECs but inhibited the proliferation effect of VEGF on HUVECs (P<0.01). CONCLUSION:These findings indicate that VEGF induces HUVECs to produce extracellular H2O2 and plays role in proliferation, but extrinsic H2O2 restrains VEGF function.  相似文献   
992.
AIM: To verify and localize the expression of nicotinamide N-methyltransferase (NNMT) in pancreas of streptozotocin(STZ)-induced diabetic monkeys and understand its important role in β-cell destruction in the pathogenesis of diabetes. METHODS: Through an olig-microarray gene chip, NNMT was identified as the most obviously up-regulated genes in pancreas of STZ-induced diabetic monkeys versus controls. Semiquantitative RT-PCR and Western blotting were performed to verify the differential expression at mRNA and protein level respectively. Then the cellular localization of NNMT expression within pancreas was identified by immunohistochemical(IHC) staining.RESULTS: An obvious high expression of NNMT at both mRNA and protein levels was shown in pancreas of STZ-induced diabetic monkeys compared to that of controls. Further localization of the protein by IHC staining in pancreas specimens showed that its altered expression was restricted to central islets, most of which were β cells.CONCLUSION: Expression of NNMT is increased in islets of STZ- induced diabetic monkeys, which infers that NNMT might participate in the process of β cell damage in diabetes probably through the mechanism of energy metabolism disturbance.  相似文献   
993.
AIM: To investigate the effect of Ganoderma lucidum spores powder on the expression of insulin-like growth factor-1 (IGF-1), nuclear factor-κB (NF-κB) and apoptosis of nerve cells in rats with epilepsy established by pentetrazole. METHODS: The sub-eclampsia dosage of pentetrazole (PTZ) was used to make epilepsy model. Ganoderma lucidum spores powder group was given from stomach. The enduring time and latent period were recorded. The immune reactivity of IGF-1, NF-κB/P65 and apoptosis of nerve cells were measured with immunohistochemical staining and TUNEL method. RESULTS: In high power sight (×400), there were much more apoptosis cells in hippocampus and brain cortex of model group (18.80±2.13, 16.87±2.00) than those in control group (0.97±0.52, 0.58±0.25). The expressions of IGF-1, NF-κB in model group were higher than those in control group. Compared with model group, the latent period of Ganoderma lucidum spores powder group at the 17th, 21th, 25th days were longer (P<0.05, P<0.05, P<0.01, respectively).There were less apoptosis cells in hippocampus and brain cortex of Ganoderma lucidum spores powder group (12.30±2.46, 10.48±1.33) than those in model group. The expression of NF-κB/P65 in Ganoderma lucidum spores powder group was lower than that in model group, but the immune reactivity of IGF-1 increased more distinctly in Ganoderma lucidum spores powder group than that in model group. CONCLUSION: IGF-1, NF-κB and apoptosis of nerve cells may have play a role in occurrence and development of PTZ-induced epilepsy. Ganoderma lucidum spores powder can suppress expression of NF-κB strongly, and facilitate the immune reactivity of IGF-1, which may be one of the mechanisms by which Ganoderma lucidum spores powder restrains the apoptosis of nerve cells caused by epilepsy to prevent the damages of nerve cells.  相似文献   
994.
AIM: To investigate the activation of nuclear factor κB (NF-κB) induced by lipopolysaccharides (LPS) in rat alveolar macrophages (AMs) and its regulatory role in tumor necrosis factor (TNF-α) secretion. METHODS: The dynamic activity changes of NF-κB induced by LPS were determined with electrophoretic mobility shift assay (EMSA). Antisense oligonucleotides of NF-κB subunit (p65) were transfected into AMs prior to LPS stimulation. The effect of antisense oligonucleotide transfection on expressions of p65 and TNF-α in supernatant were measured with Western blotting and enzyme linked immunosorbent assay (ELISA), respectively.RESULTS: NF-κB activity increased markedly and reached its peak level at 4 h after LPS stimulation. After transfected with antisense oligonucleotides of NF-κB subunit (p65), expression of p65 and TNF-α in supernatant decreased markedly.CONCLUSION: NF-κB activity has a positive effect on regulating secretion of TNF-α in AMs induced by LPS.  相似文献   
995.
996.
AIM: To Screen and identify differentially expressed genes that involved in apoptosis model in rat cerebellar granule neurons (CGNs).METHODS: The rat cerebellar granule neurons were isolated and primarily cultured.Fluorescent differential display RT-PCR (FDD RT-PCR) was performed to screen differentially expressed ESTs in the apoptosis model of primarily cultured rat CGNs.ESTs were subcloned into pGEM-T EasyTM vector and then sequenced.Alignment assay in non-redunant database was applied for encoding information.Reverse Northern blotting was used to appraise the results from DDRT-PCR.RESULTS: 164 pieces of differentially expressed ESTs were obtained by FDDRT-PCR.17 of them were subcloned and sequenced.5 ESTs of 17 were confirmed to be positive results by reverse Northern blotting.CONCLUSION: DD-PCR is a rapid,simple-operation and sensitive method for screening differentially expressed genes,which would contribute to the molecular mechanisms of apoptosis/survive of CGNs.  相似文献   
997.
简要介绍了红手球、丰锦、高砂、佐藤锦、月山锦、高阳锦、黑砂糖锦、小夏、佐槛、樱姬、绚瞳、明月、大楼夏、大将锦、南阳、花驹、红清、红秀峰、山形美人、水门、金王、正光锦、六月新娘和香夏锦等24个日本甜樱桃品种的主要经济性状.  相似文献   
998.
落叶果树需冷量及其估算模型研究进展   总被引:2,自引:0,他引:2  
落叶果树的需冷量得到满足,才能顺利完成自然休眠,进行下一个生长发育循环(尤其是正常开花结果),否则其他环境条件再适宜,果树也不萌芽开花,即使萌芽也不整齐,生长结果不良,达不到促成栽培的目的[1].因此,对落叶果树需冷量及其估算的研究至关重要,成为落叶果树设施栽培成败的关键.本文仅就需冷量估算模型进行介绍,以期为设施栽培和更完善的需冷量估算提供理论依据.……  相似文献   
999.
转基因抗病毒病四倍体西瓜的培育   总被引:1,自引:1,他引:1  
利用西瓜花叶病毒2号(WMV-2)外壳蛋白(CP)基因、小西葫芦黄花叶病毒(ZYMV)复制酶(NIb)基因和黄瓜花叶病毒(CMV)复制酶基因构建三价基因的植物表达载体,通过农杆菌介导转化四倍体西瓜植株,经分子检测证明目的基因成功地导入西瓜植株,并在后代中稳定遗传。经温室及大田接种鉴定,T3代转基因西瓜抗病毒性达中抗水平,为抗病毒无籽西瓜新品种的培育提供了可能性。  相似文献   
1000.
阿魏侧耳多糖研究进展   总被引:2,自引:1,他引:2  
闫训友  王玮  赵英 《北方园艺》2007,(12):243-245
阿魏侧耳是一种具有药用价值的名贵珍稀食用菌,具有"天然、营养、保健"于一体功能.现对阿魏侧耳的研究历史及阿魏侧耳多糖的药用价值进行综述.  相似文献   
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