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多功能植物区系名录管理系统   总被引:3,自引:1,他引:2  
薛跃规  潘祥裕  农邦寿  曾云莺   《广西植物》1997,17(2):184-186
本文探讨了计算机技术在植物区系名录管理中的应用,分析该系统的创建与编程原理。植物区系名录管理系统(FloraListManagementSystem)以下简称FLMS。FLMS在IBM及其兼容系列机上通过,它能提供植物区系名录的查询、统计、补充、修改、打印、数据通讯等服务  相似文献   
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Memory decline is characteristic of aging and age-related neurodegenerative disorders. This study was designed to investigate the protective effect of hyperbaric oxygen (HBO) against cognitive impairment induced by d-galactose (d-gal) in mice. d-gal was intraperitoneally injected into mice daily for 8 weeks to establish the aging model. HBO was simultaneously administered once daily. The results indicate that HBO significantly reversed D-gal-induced learning and memory impairments. Studies on the potential mechanisms of this action showed that HBO significantly reduced oxidative stress by increasing superoxide dismutase, glutathione peroxidase, and catalase levels, as well as the total anti-oxidation capability, while decreasing the content of malondialdehyde, nitric oxide, and nitric oxide synthase in the hippocampal CA1 region. HBO also inhibited advanced glycation end-product formation and decreased levels of tumor necrosis factor-α and interleukin-6. Moreover, HBO significantly attenuated d-gal-induced pathological injury in the hippocampus, as well as β-amyloid protein1?42 expression and retained BDNF expression. Furthermore, HBO decreased p16, p21 and p53 gene and protein expression in the hippocampus of d-gal-treated mice. In conclusion, the protective effect of HBO against d-gal-induced cognitive impairment was mainly due to its ability to reduce oxidative damage, suppress inflammatory responses, and regulate aging-related gene expression.  相似文献   
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蛇伤溃疡的外科治疗(附36例分析)   总被引:1,自引:1,他引:1  
农庆文  刘达恩 《蛇志》1996,8(4):45-46
36例蛇伤溃疡总结,结果提示,多发生于青壮年男性,手、足多见,溃疡创面有缺损、面积大,多伴皮下潜行性破坏、深部组织外露及创面感染等特点。均需外科手术处理。强调早期清创。缺损创面修复,可酌情选用刃厚、中厚、全厚等游离皮片移植或远位带蒂皮瓣转移,术后外观及功能的恢复均较满意  相似文献   
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The fungus Magnaporthe oryzae threatens the rice production of Kongyu 131 (KY131), a leading japonica variety in Northeast China. In this study, two rice lines, KP1 and KP2-Hd1, were obtained by introgressing the blast resistance genes Pi1 and Pi2 into KY131, respectively. However, both lines headed later than KY131. RICE60K SNP array analysis showed that Hd1 closely linked to Pi2 was introgressed into KP2-Hd1, and the linkage drag of Hd1 was broken by recombination. On the other hand, no known flowering genes were introgressed into KP1. Gene diagnosis by resequencing six flowering genes showed that KP1 carried functional Hd16 and Ghd8 alleles. Due to its suppression role in heading under long-day conditions, Ghd8 was chosen as the target for gene editing to disrupt its function. Four sgRNAs targeting different sites within Ghd8 were utilized to induce large-deletion mutations, which were easy to detect via agarose gel electrophoresis. All the ghd8-mutated KP1 lines were resistant to rice blast disease and headed earlier than the control KP1, even than KY131, under natural long-day conditions, which ensures its growth in Northeast China. This study confirmed that a combination of gene diagnosis and targeted gene editing is a highly efficient way to quickly eliminate undesired traits in a breeding line.  相似文献   
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Elevated plasma free fatty acid (FFA) levels in obesity may play a pathogenic role in the development of insulin resistance. However, molecular mechanisms linking FFA to insulin resistance remain poorly understood. Oxidative stress acts as a link between FFA and hepatic insulin resistance. NADPH oxidase 3 (NOX3)-derived reactive oxygen species (ROS) may mediate the effect of TNF-α on hepatocytes, in particular the drop in cellular glycogen content. In the present study, we define the critical role of NOX3-derived ROS in insulin resistance in db/db mice and HepG2 cells treated with palmitate. The db/db mice displayed increased serum FFA levels, excess generation of ROS, and up-regulation of NOX3 expression, accompanied by increased lipid accumulation and impaired glycogen content in the liver. Similar results were obtained from palmitate-treated HepG2 cells. The exposure of palmitate elevated ROS production and NOX3 expression and, in turn, increased gluconeogenesis and reduced glycogen content in HepG2 cells. We found that palmitate induced hepatic insulin resistance through JNK and p38MAPK pathways, which are rescued by siRNA-mediated NOX3 reduction. In conclusion, our data demonstrate a critical role of NOX3-derived ROS in palmitate-induced insulin resistance in hepatocytes, indicating that NOX3 is the predominant source of palmitate-induced ROS generation and that NOX3-derived ROS may drive palmitate-induced hepatic insulin resistance through JNK and p38MAPK pathways.  相似文献   
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Carbon-based metal free catalysts (CMFCs) are far away from commercial availability mainly attributed to their poor oxygen reduction reaction (ORR) performance in acidic environment with the causes remaining obscure. By investigating the heteroatoms (N, B, P, S, Se, and Te)-doped reduced graphene oxides, the degradation mechanism of acidic ORR performance of CMFCs is found to be correlated with the oxygen-baring defects in the carbon sp2 lattice, which exhibit overpotentials as low as 0.44 V but weak trapping capabilities for oxygen molecules. These findings not only revise the previously reported strategy of modeling the active sites in the basal plane of CMFCs but also highlight the connections between those active sites and the triple-coordinated VIA group elements (XC3). Further calculations demonstrate that the XC3 dimer can efficiently enhance the acidic ORR performance and the 2D trigonal carbon-chalcogenides C6X (X = S, Se, and Te) are accordingly designed toward acidic ORR, which contain homogeneously distributed basal plane active sites and exhibit low overpotentials but strong trapping capabilities for oxygen molecules. This work will help to cease the debates on the active sites in CMFCs for ORR in both acidic and alkaline solutions and to open a new avenue to design CMFCs independent on doping strategy.  相似文献   
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