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991.
AIM:To investigate the effect of berberine on IL-1 or tumour necrosis factor (TNF) induced polymorphonuclear leucocyte(PMN)-endothelium adhesion and adhesion molecules.METHODS:Based on the model of human umbilical vein endothelial cell (HUVEC), this study adopted Rose Bengal Stain, cell ELISA, immunocyto-chemical techniques to investigate the effect of berberine on PMN-endothelium adhesion and the expression of cell adhesion molecules (CAMs).RESULTS:Berberine inhibited IL-1, TNF-induced HUVEC adhesion for PMN when pretreated HUVEC and antagonised IL-1, TNF-induced upregulation of ICAM-1 on HUVEC. Meanwhile, TNF-stimulated PMN adhesion for HUVEC and CD18 upexpression on PMN was diminished in the presence of berberine.CONCLUSION: Inhibite PMN-endothelium adhesion by downregulating the CAMs expression to inhibite PMN migration across endothelium is one of the mechanisms of antiinflammation of berberine.  相似文献   
992.
AIM:To explore the relationship between change of serum melatonin (MT) and pathogenesis of hepatic encephalopathy (HE). METHODS: Changes of MT level in sera of cirrhosic patients with HE and without HE were determined by ELISA, normal serum served as control. The change of serum MT level in exacerbation and remission in HE was also determined.RESULTS:MT level in patients with HE was higher than that withour HE (P<0.01). MT levels of both groups were higher than that of normal group (P<0.01). They were (308.53±59.07) ng/L, (139.85±34.59)ng/L,(77.73±28.41)ng/L, respectively. Serum MT level in exacerbation was higher than that in remission (P<0.01), they were (301.52±66.42)ng/L and (147.81±23.31) ng/L, respectively. CONCLUSION: The elevation of MT content in sera may be closely related to the onset of hepatic coma.  相似文献   
993.
Neurovascular unit (NVU) is composed of neurons, endothelial cells, pericytes, astrocytes, macrophages/microglia, smooth muscle cells, extracellular matrix, etc, and plays vital roles in maintenance of the normal brain tissue function and cellular homeostasis. Cerebral ischemia caused by stroke can harm various components of NVU. Repairing damaged NVU and maintaining its structural and functional integrity are an effective way to improve stroke treatment. Resent research has found that rapamycin not only enhances autophagy of neurons but also effectively repairs the injuried components of NVU , thereby reducing neural damage after stroke. In this paper, the mechanisms of rapamycin underlying the repair of injured NVU after ischemic stroke is reviewed to provide guidance for its application in the treatment of stroke.  相似文献   
994.
AIM To investigate the mechanism of long noncoding RNA (lncRNA) FEZF1-AS1 regulating microRNA-363-3p (miR-363-3p) on the viability and apoptosis of lipopolysaocharide (LPS)-induced vascular endothelial cells. METHODS Human umbilical vein endothelial cells (HUVECs) were cultured in vitro. pcDNA-NC, pcDNA-FEZF1-AS1, anti-miR-NC, anti-miR-363-3p, miR-NC and miR-363-3p mimics were transfected into the HUVECs and LPS stimulation was applied for 24 h. RT-qPCR was used to detect the expression of FEZF1-AS1 and miR-363-3p. The cell viability was measured by MTT assay. The apoptotic rate was analyzed by flow cytometry. The dual-luciferase reporter experiment was used to verify the targeted regulation of FEZF1-AS1 and miR-363-3p. Western blot was used to determined the expression of cyclin D1, Ki67 and cleaved caspase-3. RESULTS Compared with control group, the expression level of FEZF1-AS1 in LPS group was significantly reduced (P<0.05), and the expression level of miR-363-3p was significantly increased (P<0.05). Compared with pcDNA-NC+LPS group, the cell viability in pcDNA-FEZF1-AS1+LPS group was significantly increased (P<0.05), the apoptotic rate was significantly reduced (P<0.05), the protein levels of cyclin D1 and Ki67 were significantly increased (P<0.05), and the protein level of cleaved caspase-3 was significantly reduced (P<0.05). Compared with anti-miR-NC+LPS group, the cell viability in anti-miR-363-3p+LPS group was significantly increased (P<0.05), the apoptotic rate was significantly reduced (P<0.05), the protein levels of cyclin D1 and Ki67 were significantly increased (P<0.05), and the protein level of cleaved caspase-3 was significantly reduced (P<0.05). Dual-luciferase reporter experiment confirmed that FEZF1-AS1 targeted miR-363-3p. Compared with miR-NC+pcDNA-FEZF1-AS1+LPS group, the cell viability in miR-363-3p+pcDNA-FEZF1-AS1+LPS group was significantly reduced (P<0.05), the apoptotic rate was significantly increased (P<0.05), the protein levels of cyclin D1 and Ki67 were significantly reduced (P<0.05), and the protein level of cleaved caspase-3 was significantly increased (P<0.05). CONCLUSION Over-expression of FEZF1-AS1 promotes the viability and inhibits apoptosis of LPS induced vascular endothelial cells by inhibiting the expression of miR-363-3p.  相似文献   
995.
为明确海水胁迫对火龙果生长生理的影响,以不同品种火龙果(‘帝龙’、‘红龙’、‘紫蜜龙’和‘白龙’)为研究对象,研究了海水(浓度为0、10%、20%和30%)浇灌下不同品种火龙果生长指标和生理特征的变化。结果表明:(1)海水浇灌下4个品种火龙果地上部鲜重均表现为减小趋势,但10%海水浇灌可显著增加‘帝龙’的株高增加量。(2)与淡水相比,海水浇灌下4个品种火龙果地上部和根部K+/Na+均呈不同程度下降趋势,当海水浓度为30%时,与其他3个品种相比,‘帝龙’地上部和根部K+/Na+下降幅度最小。(3)4个品种火龙果地上部可溶性糖含量、脯氨酸含量、CAT活性和SOD活性随海水浓度增加均呈先上升后下降趋势。其中,20%海水处理下,‘帝龙’可溶性糖含量、脯氨酸含量和CAT活性上升幅度均高于其他品种。可见,低浓度海水胁迫下,火龙果表现出一定耐盐性,且‘帝龙’耐盐性相对较好。  相似文献   
996.
从生产毒死蜱农药厂采集的活性污泥中分离筛选得到2株降解效率较高的毒死蜱降解菌,命名为D1、D3,根据表型特征、生理生化特性和16 S rRNA基因序列相似性分析,将其鉴定为苍白杆菌属(Ochrobactrum sp.)和副球菌属(Paracoccus sp.)细菌。2株菌以最佳配比(1∶1.25)混合施用时,与单菌相比,毒死蜱降解效率可提高12%~26%;以混合菌株为研究对象,发现其对毒死蜱最适降解温度为30℃,最适降解pH值为7.0,最适NaCl浓度为0.5%;混合菌株施入土壤后,可保持较高的定殖能力和降解效率。  相似文献   
997.
武夷岩茶种质资源遗传多样性与亲缘关系的SRAP分析   总被引:1,自引:0,他引:1  
本研究利用SRAP-PCR反应体系,从88对SRAP引物组合中筛选出43对引物组合,对武夷岩茶主要的30份种质资源进行SRAP分析,共扩增出385条带,其中具有多态性的有236条带,占总数的61.30%,表明30份武夷岩茶种质呈现一定的遗传多样性。武夷岩茶种质资源间遗传距离变幅在0.31~0.98之间,平均为0.63,基于SRAP标记利用系统聚类法把武夷岩茶分为三大类,为武夷岩茶遗传研究、品种选育与资源保护提供参考。  相似文献   
998.
为研究菠萝蜜果肉类胡萝卜素分析方法、分析呈色组分,本研究基于高效液相色谱法检测果肉中类胡萝卜素组分,通过比较不同色泽果肉中类胡萝卜素物质差异,鉴定呈色组分。结果表明,用含0.01%BHT的正己烷∶丙酮∶无水乙醇(2∶1∶1,V/V/V)作为提取液,结合超声震荡、皂化脱脂等步骤,能有效提取菠萝蜜果肉中总类胡萝卜素。组分分析采用YMC carotenoid column C30(4.6×250 mm)色谱柱,二极管阵列检测器(photodiode array,PDA)在450 nm波长下,检测出16种不同的类胡萝卜素组分。定量结果表明,β-柠乌素是红色果肉的呈色组分,紫黄质是黄肉果肉主要的呈色组分。差异组分之间存在一定的代谢关联,即紫黄质合成前体的裂解反应及下游异构化反应是造成果肉色泽差异的潜在原因。  相似文献   
999.
大豆是我国重要的油料作物和高蛋白粮饲兼用作物,具有与根瘤菌共生固氮的能力。近十几年来,我国大豆品种更新快,导致大豆根瘤菌株与新品种匹配能力差、接种效果不明显。筛选与主栽大豆品种匹配性好、固氮效率高的广谱性优良菌株,可为针对性的施用大豆根瘤菌接种剂提供菌种资源和方案。选取本实验室前期分离保存的6个优良快生型大豆根瘤菌株和2个慢生型大豆根瘤菌株,在砂培盆栽条件下与不同地区的27个大豆主栽品种进行匹配试验。测定分析了植株地上部分生物量、高度、根瘤数量、根瘤生物量和根瘤固氮酶活指标。结果表明:不同大豆根瘤菌之间结瘤固氮能力存在极显著的差异;供试根瘤菌均能够与国内24个大豆品种结瘤,广谱性较好;植株地上部分高度、根瘤数量、根瘤生物量和根瘤固氮酶活与地上部分生物量呈显著相关;大部分接种根瘤菌后的植物生物量显著高于CK;HN01、GR3、HH29、HH103匹配性和固氮效率均不逊色于USDA110,具有在东北地区、黄淮海地区、长江流域、东南地区推广的潜能;从品种来看,中豆39、BD2、天隆1号与8株供试大豆根瘤菌的匹配接种表现出高生物量特点。此外,本文还筛选出大豆-大豆根瘤菌的表型最佳匹配组合中豆39-GR3,适合长江流域地区;同样筛选到东北地区、黄淮海地区、东南地区最佳匹配组合,分别是HN01-辽豆14、HN01-徐豆14、HN01-BD2。本文初步建立了优良根瘤菌与大豆主栽品种的匹配关系,为在田间试验中进一步筛选和应用这些优良菌株提供了材料和指导。  相似文献   
1000.
为探讨昆虫为杂交大豆授粉的行为,提高授粉效率,以大豆细胞质雄性不育系JLCMS34A和保持系JLCMS34B为材料,研究父母本3种行距配置(T1、T2、T3)对昆虫授粉行为及产量构成的影响。结果表明:行距配置T2条件下昆虫授粉效率最高,母本单株粒数最多,为45.98个(2011年),与T1、T3差异达到显著水平,T3配置授粉效率最差,单株粒数最少,为32.06个(2012年),与T1、T2差异达到极显著水平。在吉林省洮南地区适当缩小父母本行距,增加母本间行距可有效促进昆虫授粉效率,提高结实率。  相似文献   
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