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51.
中药博落回的药理实验研究 总被引:1,自引:0,他引:1
博落回对四氯化碳、半乳糖胺所致急性肝损伤模型,均有显著改善肝脏功能作用;对四氯化碳所致慢性肝损伤大鼠模型,博落回可显著降低血清LDH水平。降低动物死亡率。提高血清A/G比值,有效保护肝细胞胰。抑制肝脏纤维化;博落回还可显著增强T和B淋巴细胞功能。 相似文献
52.
T Kohl N Gehrke A Schad M Nagel M A W?rns M F Sprinzl T Zimmermann Y-W He P R Galle M Schuchmann J M Schattenberg 《Cell death & disease》2013,4(7):e712
The endemic occurrence of obesity and the associated risk factors that constitute the metabolic syndrome have been predicted to lead to a dramatic increase in chronic liver disease. Non-alcoholic steatohepatitis (NASH) has become the most frequent liver disease in countries with a high prevalence of obesity. In addition, hepatic steatosis and insulin resistance have been implicated in disease progression of other liver diseases, including chronic viral hepatitis and hepatocellular carcinoma. The molecular mechanisms underlying the link between insulin signaling and hepatocellular injury are only partly understood. We have explored the role of the antiapoptotic caspase-8 homolog cellular FLICE-inhibitory protein (cFLIP) on liver cell survival in a diabetic model with hypoinsulinemic diabetes in order to delineate the role of insulin signaling on hepatocellular survival. cFLIP regulates cellular injury from apoptosis signaling pathways, and loss of cFLIP was previously shown to promote injury from activated TNF and CD95/Apo-1 receptors. In mice lacking cFLIP in hepatocytes (flip−/−), loss of insulin following streptozotocin treatment resulted in caspase- and c-Jun N-terminal kinase (JNK)-dependent liver injury after 21 days. Substitution of insulin, inhibition of JNK using the SP600125 compound in vivo or genetic deletion of the mitogen-activated protein kinase (MAPK)9 (JNK2) in all tissues abolished the injurious effect. Strikingly, the difference in injury between wild-type and cFLIP-deficient mice occurred only in vivo and was accompanied by liver-infiltrating inflammatory cells with a trend toward increased amounts of NK1.1-positive cells and secretion of proinflammatory cytokines. Transfer of bone marrow from rag-1-deficient mice that are depleted from B and T lymphocytes prevented liver injury in flip−/− mice. These findings support a direct role of insulin on cellular survival by alternating the activation of injurious MAPK, caspases and the recruitment of inflammatory cells to the liver. Thus, increasing resistance to insulin signaling pathways in hepatocytes appears to be an important factor in the initiation and progression of chronic liver disease. 相似文献
53.
Zhang LX Tong XJ Sun XH Tong L Gao J Jia H Li ZH 《Cellular and molecular neurobiology》2008,28(4):501-509
Objectives To observe the effect of ultrashortwave (USW) therapy on nerve regeneration after acellular nerve allografts(ANA) repairing
the sciatic nerve gap of rats and discuss its acting mechanisms. Methods Sixteen Wistar rats weighing 180–220 g were randomly divided into four groups with four rats in each group: normal control
group; acellular group (ANA, treated by hypotonic-chemical detergent, was applied for bridging a 10 mm-long sciatic nerve
defect); USW group (After 24 h of ANA repairing the sciatic nerve gap, low dose USW was administrated for 7 min, once a day,
20 times a course of treatment, three courses of treatment in all); and autografts group. 12 weeks after operation, a series
of examinations was performed, including electrophysiological methods, the restoring rate of tibialis anterior muscle wet
weight, histopathological observation (myelinated nerve number, myelin sheath thickness, and axon diameter), vascular endothelial
growth factor (VEGF) mRNA expression of spinal cord, and muscle at injury site, and analyzed statistically. Results Compared to acellular nerve allografts alone, USW therapy can increase nerve conductive velocity, the restoring rate of tibialis
anterior muscle wet weight, myelinated nerve number, axon diameter, VEGF mRNA expression of spinal cord, and muscle at injury
site, the difference is significant. There were no differences between USW group and autografts group except myelin sheath
thickness. Conclusions USW therapy can promote nerve axon regeneration and Schwann cells proliferation after ANA repairing the sciatic nerve gap
of rats, the upregulation of VEGF mRNA expression of spinal cord and muscle may play an important role. 相似文献
54.
黑色素是一种广泛存在于动物、植物、细菌及真菌中的生物色素,具有多种生物功能及良好的生物活性。黑木耳以“黑”出名,其富含的黑色素具有广阔开发应用价值。本研究旨在评价黑木耳黑色素对急性肝损伤的改善作用。首先应用傅里叶红外光谱初步对提取的黑木耳黑色素进行鉴定,再通过DPPH自由基及羟基自由基清除实验证实提取的黑木耳黑色素体外抗氧化能力,并进一步以四氯化碳致小鼠急性肝损伤为模型,通过检测血清酶指标、肝功指标的变化及病理切片情况,来评价黑木耳黑色素体内抗氧化及保肝效果。结果表明,提取的黑木耳黑色素具有黑色素特征的官能团结构和良好的体外抗氧化能力,对DPPH自由基和羟基(OH)自由基清除的EC50分别为0.0887mg/mL、2.2030mg/mL;动物体内实验中,与模型组对比,给药组(黑木耳黑色素)的小鼠血清中ALT、AST含量显著降低(P<0.01),肝脏中MDA含量显著降低(P<0.01)和SOD活性显著升高(P<0.01),并且肝细胞病理状态明显改善。本文报道了黑木耳黑色素在体内能有效改善四氯化碳诱导的小鼠肝损伤,为黑木耳的功能产品开发提供了新思路和研究基础。 相似文献
55.
56.
Ishwar Singh Upendra Kumar S. K. Singh Charu Gupta Madhulika Singh S. R. Kushwaha 《Physiology and Molecular Biology of Plants》2012,18(3):229-236
Germination and early seedling growth are important for establishment of maize because maize is chilling sensitive crop and low temperature during early period of growth can be detrimental to subsequent crop growth and productivity. Therefore, it is important to protect maize seedling from cold stress. A study was conducted on induced cold tolerance by 24-epibrassinoslide (EBR) at the Indian Agricultural Research Institute, New Delhi, India. Maize seedlings were raised in green house condition (25/18 °C day-night temperatures). Ten days old seedlings were treated with EBR (0.0, 0.01, 0.1, 1.0 and 10 μM) and then divided into two sets, one set was kept in greenhouse (25/18 °C day-night temperatures) and another was transferred to net house (cold stress). Data on various morpho-physiological traits was recorded after 7, 14 and 21 days of treatment. Exogenous application of 1.0 μM EBR had significant effect on growth and morpho-physiological traits under both conditions. The maize seedlings treated with EBR were more tolerant to cold stress than the untreated one. Significant increase in plant height, dry matter accumulation, chlorophyll content, total soluble proteins and starch contents was observed under both conditions, however, the results were more pronounced under cold stress. 1.0 μ M concentration being the most effective under both conditions. Maintenance of high tissue water content, reduced membrane injury index, increased total chlorophyll, soluble sugar and protein content were taken as the possible indicators of EBR induced chilling tolerance. 相似文献
57.
Jiyang Xue Hanwei Ge Zhiyong Lin Hanlei Wang Wei Lin Yong Liu Guowei Wu Jie Xia Qifeng Zhao 《Journal of cellular and molecular medicine》2019,23(4):2849-2862
Inflammatory response plays an important role in ischaemia reperfusion injury (IRI) through a variety of inflammatory cells. Apart from neutrophils, macrophages and lymphocytes, the role of dendritic cells (DCs) in IRI has been noticed. The study was aimed at investigating whether the high‐mobility group protein box‐1/toll like receptor 4 (HMGB1/TLR4) signalling pathway regulate the migration, adhesion and aggregation of DCs to the myocardium, induce DCs activation and maturation, stimulate the expression of surface costimulatory molecules and participate in myocardial IRI. In vivo, migration, adhesion, and aggregation of DCs was enhanced; the expression of peripheral blood DCs CD80 and CD86, myocardial adhesion molecules were increased; and the infarct size was increased during myocardial ischaemia reperfusion injury myocardial ischemic/reperfusion injury (MI/RI). These responses induced by MI/RI were significantly inhibited by HMGB1 specific neutralizing antibody treatment. Cellular experiments confirmed that HMGB1 promoted the release of inflammatory cytokines through TLR4/MyD88/NF‐κB, upregulated CD80 and CD86 expression, mediated the damage of cardiomyocytes and accelerated the apoptosis. Our results indicate that DCs activation and maturation, stimulate the expression of surface costimulatory molecules by promoting the release of inflammatory factors through NF‐κB pathway and participate in myocardial IRI. 相似文献
58.
59.
气候变化对黑龙江省水稻障碍型冷害的影响 总被引:3,自引:0,他引:3
明确气候变化对黑龙江省水稻孕穗期和抽穗期障碍型冷害的影响,可为水稻安全生产提供科学依据。基于黑龙江省70个台站1971—2012年的气象资料和10个台站1980—2011年水稻生育期数据,结合水稻障碍型冷害指标,分析了气候变化对黑龙江省水稻障碍型冷害的影响。结果表明:(1)水稻孕穗期障碍型冷害1990s发生频率最低,2000s发生频率最高;抽穗期障碍型冷害1970s和1980s发生频率高,1990s和2000s发生频率低。(2)抽穗期障碍型冷害发生程度大于孕穗期障碍型冷害。(3)不同熟型水稻品种可种植北界逐渐北移东扩,极早熟、早熟和中熟品种可种植范围分别缩小了5、21和11个县(市),中晚熟和晚熟品种可种植范围分别扩大了14和23个县(市)。(4)随着水稻种植格局的变化,不同熟型水稻障碍型冷害均在1990s发生频率最低,2000s发生频率最高。 相似文献
60.
Nicholas Ali Michael Skipper Andersen John Rasmussen D. Gordon E. Robertson Gholamreza Rouhi 《Computer methods in biomechanics and biomedical engineering》2014,17(14):1602-1616
The central tenet of this study was to develop, validate and apply various individualised 3D musculoskeletal models of the human body for application to single-leg landings over increasing vertical heights and horizontal distances. While contributing to an understanding of whether gender differences explain the higher rate of non-contact anterior cruciate ligament (ACL) injuries among females, this study also correlated various musculoskeletal variables significantly impacted by gender, height and/or distance and their interactions with two ACL injury-risk predictor variables; peak vertical ground reaction force (VGRF) and peak proximal tibia anterior shear force (PTASF). Kinematic, kinetic and electromyography data of three male and three female subjects were measured. Results revealed no significant gender differences in the musculoskeletal variables tested except peak VGRF (p = 0.039) and hip axial compressive force (p = 0.032). The quadriceps and the gastrocnemius muscle forces had significant correlations with peak PTASF (r = 0.85, p < 0.05 and r = ? 0.88, p < 0.05, respectively). Furthermore, hamstring muscle force was significantly correlated with peak VGRF (r = ? 0.90, p < 0.05). The ankle flexion angle was significantly correlated with peak PTASF (r = ? 0.82, p < 0.05). Our findings indicate that compared to males, females did not exhibit significantly different muscle forces, or ankle, knee and hip flexion angles during single-leg landings that would explain the gender bias in non-contact ACL injury rate. Our results also suggest that higher quadriceps muscle force increases the risk, while higher hamstring and gastrocnemius muscle forces as well as ankle flexion angle reduce the risk of non-contact ACL injury. 相似文献