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带滤芯顶驱方保接头在海上油田的使用 被引量:1
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作者 林俊文 张飞 +2 位作者 王昆剑 王晓琪 丁晓洁 《石化技术》 CAS 2016年第12期116-117,共2页
本文介绍了一种带滤芯顶驱方保接头在海上油田的应用情况,并对应用效果进行了分析。结果表明,对于方保接头的悬挂结构及滤芯的性能可以实现双台阶密封钻杆钻井液过滤的现场要求,同时也提出了改进措施,为在海洋钻井工程领域中广泛应用奠... 本文介绍了一种带滤芯顶驱方保接头在海上油田的应用情况,并对应用效果进行了分析。结果表明,对于方保接头的悬挂结构及滤芯的性能可以实现双台阶密封钻杆钻井液过滤的现场要求,同时也提出了改进措施,为在海洋钻井工程领域中广泛应用奠定了基础。 展开更多
关键词 带滤芯 顶驱方保接头 双台阶密封钻杆 钻杆钻井液过滤 改进措施
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一种顶部驱动系统方保接头滤网装置的改造设计
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作者 黄祯 李文拓 《广东化工》 CAS 2019年第1期125-125,129,共2页
由于井下仪器精密度高,通常在钻杆内部放置滤网,过滤钻井液中较大杂质,保证随钻工具正常运行。但钻井现场作业越来越多的使用无内台阶的钻杆,从而无法在钻杆内部放置滤网控制钻井液杂质,从而导致随钻工具出现故障。通过对顶驱方保接头... 由于井下仪器精密度高,通常在钻杆内部放置滤网,过滤钻井液中较大杂质,保证随钻工具正常运行。但钻井现场作业越来越多的使用无内台阶的钻杆,从而无法在钻杆内部放置滤网控制钻井液杂质,从而导致随钻工具出现故障。通过对顶驱方保接头进行改进,内部加工能够安置滤网装置的键槽,创新性解决了无内台阶钻杆钻井液过滤问题。改进后的装置结构简单,加工方便,投资成本低;应用前景良好,可以实现无内台阶钻杆钻井液过滤问题;经济效益显著,可在海洋和陆地油气田工程领域中广泛应用。 展开更多
关键词 钻井 顶驱 滤网 方保接头 改进
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保肺化纤方调控TGF-β1/smad2/3、Wnt1/β-catenin信号通路对BLM/PM2.5诱导的特发性肺纤维化大鼠肺组织胶原沉积的影响
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作者 马宁怡 千孟丹 +5 位作者 何慧慧 刘学芳 冯素香 刘素晓 林珊珊 李亚 《辽宁中医杂志》 CAS 北大核心 2024年第9期191-195,I0005,共6页
目的探讨保肺化纤方经转化生长因子(transforming growth factor,TGF)-β1/smad2/3、Wnt1/β-连环蛋白(catenin)信号通路减轻博来霉素(bleomycin,BLM)/PM2.5暴露诱导的特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)大鼠肺组织胶... 目的探讨保肺化纤方经转化生长因子(transforming growth factor,TGF)-β1/smad2/3、Wnt1/β-连环蛋白(catenin)信号通路减轻博来霉素(bleomycin,BLM)/PM2.5暴露诱导的特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)大鼠肺组织胶原沉积的作用机制。方法SD大鼠随机分为对照(Control)组、BLM+PM2.5(Model)组、保肺化纤方(BHF)组、吡非尼酮(pirfenidone,PFD)组、XAV-939组、BHF+PFD组、BHF+XAV-939组。采用一次性气管内雾化BLM法制备IPF大鼠模型,大气PM2.5实时浓缩全身暴露和给予相应药物干预。检测大鼠肺功能,观察肺组织病理和胶原沉积;采用免疫组化技术检测肺组织Ⅰ、Ⅳ型胶原(collagen,COL)、TGF-β1、smad2/3、β-catenin蛋白水平;采用qPCR技术检测肺组织TGF-β1、smad2/3、Wnt1、β-catenin mRNA水平。结果与Control组比较,Model组大鼠肺功能显著降低(P<0.01),肺组织可见大量炎症细胞浸润,肺泡壁断裂、增厚,胶原沉积等肺纤维化特征性病理改变,肺组织胶原容积分数(collagen volume fraction,CVF)、COLⅠ、COLⅣ蛋白及TGF-β1、smad2/3、β-catenin基因与蛋白表达均显著升高(P<0.01);与Model组比较,各治疗组均有效改善大鼠肺组织病理改变,显著降低肺组织CVF及COLⅠ、COLⅣ、TGF-β1、smad2/3、β-catenin蛋白表达水平(P<0.05,P<0.01),同时BHF组、BHF+PFD组、BHF+XAV-939组均能显著提高大鼠肺功能(P<0.05,P<0.01),明显下调肺组织TGF-β1、smad2/3、β-catenin基因表达水平(P<0.01);与PFD组比较,BHF+PFD组大鼠肺组织COLⅠ、TGF-β1蛋白及smad2、β-catenin基因表达均显著降低(P<0.05,P<0.01);与XAV-939组比较,BHF+XAV-939组smad3基因表达显著降低(P<0.01)。结论保肺化纤方可改善BLM/PM2.5诱导的IPF大鼠肺组织病理损伤,减少胶原沉积,提高肺功能,改善肺纤维化,其机制可能与下调TGF-β1/smad2/3、Wnt1/β-catenin通路有关。 展开更多
关键词 特发性肺纤维化 保肺化纤方 胶原沉积 TGF-β1/smad2/3 Wnt1/β-catenin PM2.5
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自拟方新贝保肝降脂汤治疗非酒精性脂肪肝的疗效观察 被引量:4
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作者 孙维华 甘霞 赵新芳 《中国中医基础医学杂志》 CAS CSCD 北大核心 2014年第10期1435-1437,共3页
目的:探讨自拟方新疆贝母保肝降脂汤治疗非酒精性脂肪肝的疗效。方法:100例NAFL患者随机分为观察组与对照组每组各50例。对照组患者给予血脂康胶囊,观察组给予自拟方保肝降脂汤,3个月后比较2组血脂、肝功能、血液流变学、B超分度积分并... 目的:探讨自拟方新疆贝母保肝降脂汤治疗非酒精性脂肪肝的疗效。方法:100例NAFL患者随机分为观察组与对照组每组各50例。对照组患者给予血脂康胶囊,观察组给予自拟方保肝降脂汤,3个月后比较2组血脂、肝功能、血液流变学、B超分度积分并评价疗效。结果:观察组总有效率88.0%(44/50),对照组68.0%(34/50),差异有统计学意义(χ2=5.47,P<0.05)。2组治疗后肝功能及血脂水平均较治疗前显著改善(P<0.05),观察组改善显著优于对照组(P<0.05)。观察组治疗后红细胞压积、全血比黏度、血浆比黏度、纤维蛋白原均较治疗前显著降低(P<0.05),对照组治疗前后各指标无明显变化(P>0.05),2组治疗后各指标比较差异均有统计学意义(P<0.05)。结论:自拟方新疆贝母保肝降脂汤治疗非酒精性脂肪肝可显著降低血脂,改善血液流变性及肝功能且无不良反应,值得临床推广应用。 展开更多
关键词 自拟方保肝降脂汤 非酒精性脂肪肝 血脂康胶囊
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卢浮宫或隔离墙 方言存废之我见 被引量:2
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作者 毛翰 《渤海大学学报(哲学社会科学版)》 2012年第1期23-26,154,共5页
多一种语言存在,就等于人间多了一堵隔离墙。汉语内部,方言已没有继续存在的必要。北方话作为胜出的一方应该谦卑,南方话也不必过于自恋。方言的割据还是民族分裂的隐患。不妨像当年推行"书同文"、"车同轨"一样,理... 多一种语言存在,就等于人间多了一堵隔离墙。汉语内部,方言已没有继续存在的必要。北方话作为胜出的一方应该谦卑,南方话也不必过于自恋。方言的割据还是民族分裂的隐患。不妨像当年推行"书同文"、"车同轨"一样,理直气壮地推行"语同音"。实行普通话与方言的双语政策,其弊远大于利,完全不可行。 展开更多
关键词 方言 方保 书同文 语同音
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降糖保肾方对早期糖尿病大鼠肾脏氧化应激与超微结构的影响 被引量:3
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作者 谢辉 汪华林 +2 位作者 黄霖 刘长波 杨热电 《中国中医急症》 2006年第10期1133-1135,共3页
目的探讨早期糖尿病大鼠肾脏氧化应激与超微结构的变化及中药方剂降糖保肾方对其影响。方法用链脲佐菌素(STZ)诱导糖尿病大鼠模型,将实验动物分为正常对照组(C组)、糖尿病组(D组)和中药组(Z组),5周末检测三组大鼠血糖(BG)、糖化血红蛋白... 目的探讨早期糖尿病大鼠肾脏氧化应激与超微结构的变化及中药方剂降糖保肾方对其影响。方法用链脲佐菌素(STZ)诱导糖尿病大鼠模型,将实验动物分为正常对照组(C组)、糖尿病组(D组)和中药组(Z组),5周末检测三组大鼠血糖(BG)、糖化血红蛋白(HbAlc)、总胆固醇(TC)、甘油三酯(TG)、血尿素氮(BUN)、肌酐(SCr)、肌酐清除率(CCr)、肾重/体重(S/T)、尿白蛋白排泄率(UAER)等指标的变化以及肾皮质总超氧化物歧化酶(TSOD)、过氧化氢酶(CAT)的活性、丙二醛(MDA)的水平;利用透射电子显微镜观察肾脏足细胞超微结构。结果Z组与C组间各指标无显著性差异;D组与Z组或C组比较,BG、HbA1c、TC、TG、S/T明显升高;BUN、SCr水平无显著性差异,但CCr显著下降;抗氧化酶中,TSOD、CAT活性明显下降,MDA水平明显升高;UAER增高,足细胞部分足突融合。结论早期糖尿病大鼠肾脏即存在氧化应激反应及肾小球滤过屏障足细胞的损害,降糖保肾方能显著改善早期糖尿病大鼠肾脏的氧化应激状态及超微结构变化。 展开更多
关键词 糖尿病 糖尿病肾病 降糖保肾方 氧化应激 足细胞 大鼠
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Neuroprotective Effects of Bushen Decoction Against Glutamate-Induced Neurotoxicity in PC12 Cells 被引量:1
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作者 贺文彬 张俊龙 +2 位作者 陈乃宏 张岭 朱海波 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期119-124,共6页
Aim The enhanced effect of Bushen (Kidney-tonifying) decoction (BS) oncultured PC12 cell proliferation and its antagonistic action on neurotoxicity induced by glutamatewere investigated by serum pharmacological method... Aim The enhanced effect of Bushen (Kidney-tonifying) decoction (BS) oncultured PC12 cell proliferation and its antagonistic action on neurotoxicity induced by glutamatewere investigated by serum pharmacological method of the Chinese material medica (CMM) in vitro.Methods The effect of BS on cultured PC12 cell activity and its antagonistic action on neurotoxicityinduced by glutamate was observed by MTT method. Flow cytometry and fluorescence microscopetechniques were employed to observe the antagonistic effect of BS on early period apoptosis of PC12cells induced by glutamate. Results The serum with BS was able to enhance activity of PC12 cells andexert antagonistic effect on glutamate-induced neurotoxicity. Meanwhile, these beneficial effectsproduced by BS were found to be the strongest in 20% concentration of in serum BS. Moreover, it caninhibit apoptosis of PC12 cells induced by glutamate , which occurs in the early period. ConclusionBS may exert a potential neuroprotective effect. 展开更多
关键词 bushen decoction neuroprotective effect APOPTOSIS pharmacology chinesematerial medica PC12 cells
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NEW PRINCIPLE FOR DIRECTIONAL COMPARISON CARRIER PROTECTION OF EHV TRANSMISSION LINES 被引量:1
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作者 王钢 李遥 +2 位作者 余晓丹 刘众仆 贺家李 《Transactions of Tianjin University》 EI CAS 1998年第2期6-10,共5页
The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave ch... The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave channels is the most suitable protection scheme for long distance EHV transmission lines and is widely used in power systems.The key element of such protection is a directional relay used to discriminate the fault direction.In order to overcome the disadvantages of conventional directional relays,the authors of this paper put forward the directional comparison carrier protection based on the artificial neural network(ANN).The protection is extensively tested using electromagnetic transient program (EMTP) under various electric power system operating and fault conditions.It is proved that the directional comparison carrier protection based on ANN,which can recognize various fault patterns of the protected transmission line(such as fault direction,fault phases etc.)correctly in any kind of operating and fault conditions and the whole process,is satisfactory for EHV transmission line protection. 展开更多
关键词 artificial neural network EHV transmission line directional comparison carrier protection
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Discussion on Feasibility of Adjustment Program for Jiangmen Chinese White Dolphin Provincial Nature Reserve 被引量:1
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作者 吴洽儿 李纯厚 +3 位作者 孙典荣 Qia-er Chun-hou Dian-rong 《Agricultural Science & Technology》 CAS 2010年第5期144-147,共4页
From the protection of Chinese white dolphin and living environment,and considering the industrial development in coastal areas,we put forward adjustment program for Jiangmen Chinese White Dolphin Provincial Nature Re... From the protection of Chinese white dolphin and living environment,and considering the industrial development in coastal areas,we put forward adjustment program for Jiangmen Chinese White Dolphin Provincial Nature Reserve. Meanwhile we analyzed the feasibility of this program by systematically focusing the effect of adjusted functional regions on Chinese white dolphin. 展开更多
关键词 Chinese white dolphin Reserve Adjustment Feasibility
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电力市场中计算输电电价的一种新方法 被引量:28
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作者 任震 吴国玥 黄雯莹 《中国电机工程学报》 EI CSCD 北大核心 2003年第1期37-40,170,共5页
该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合... 该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合理、完善。经IEEE6节点系统算例证明,该文所提的模型和算法是正确而有效的,具有重要的理论意义和工程实际价值,特别是对于在厂网分开后电网建设以及维护电网稳定的资金筹措有相当的指导价值。 展开更多
关键词 电网 无功功率 边际成本理论 潮流计算 电力市场 输电电价
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个性化护理干预联合保肾通络方对慢性肾病综合征患者的治疗及肾功能指标的影响 被引量:5
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作者 王莹莹 王素萍 葛亚辉 《实用中医内科杂志》 2022年第2期55-57,共3页
目的研究个性化护理干预联合保肾通络方对慢性肾病综合征患者的治疗及肾功能指标的影响。方法选取2018年5月—2020年5月医院收治的104例慢性肾病综合征患者,随机分为两组,各52例。对照组给予保肾通络方治疗,并给予常规护理干预,观察组... 目的研究个性化护理干预联合保肾通络方对慢性肾病综合征患者的治疗及肾功能指标的影响。方法选取2018年5月—2020年5月医院收治的104例慢性肾病综合征患者,随机分为两组,各52例。对照组给予保肾通络方治疗,并给予常规护理干预,观察组在对照组基础上增加个性化护理干预。对两组患者的临床疗效、肾功能指标、生活质量、护理满意度等进行评估比较。结果观察组总有效率90.38%(47/52),高于对照组患者75.00%(39/52)(P<0.05)。治疗后观察组患者的24 h尿蛋白定量(24 hpro)、血清尿素氮(BUN)、血肌酐(Scr)水平均低于对照组(P<0.05)。观察组生活质量各项评分均高于对照组(P<0.05)。观察组护理满意度为92.31%(48/52),高于对照组患者为76.92%(40/52)(P<0.05)。结论个性化护理干预联合保肾通络方对慢性肾病综合征患者的治疗效果显著,改善患者的肾功能指标和生活质量,改善患者的护理满意度。 展开更多
关键词 慢性肾病综合征 保肾通络方 个性化护理 临床疗效 肾功能指标
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Study on Preservative Formula and Shelf Life of Cantonese Style Moon Cakes 被引量:3
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作者 林真 张温玲 陈健 《Agricultural Science & Technology》 CAS 2017年第11期2171-2174,共4页
To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moo... To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moon cake were studied. Through single and compound formula preservative test, the results showed that potassium sorbate and sodium dehydroacetate could inhibit the microorganisms in the moon cake, but the inhibitory effect of sodium dehydroacetate was stronger than that of potassium sorbate; and the combination of potassium sorbate and sodium dehydroacetate had a synergistic effect, and the best formula is 'potassium sorbate 0.44 g/kg mixed with sodium dehydroacetate 0.38 g/kg. A batch of moon cake was prepared with the best preservative formula, then the total number of colonies, molds and coliform group in the samples were detected by random sampling at irregular intervals. The total number of molds exceeded the limit on the 187^th d, and it indicated that the shelf life of the product was 187 d. Compared with the conventional 15-day shelf life, this research greatly prolongs the sheff life of cantonese style moon cake, and cut down the cost of moon cake enterprises. It is worthy of popularization and application. 展开更多
关键词 Cantonese style moon cakes Potassium sorbate Sodium dehydroacetate Formula optimization Shelf life
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Preservation of non-heart-beating donor livers in extracorporeal liver perfusion and histidine-trytophan-ketoglutarate solution 被引量:4
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作者 Jin Gong Xue-Jun Lao +3 位作者 Xi-Mo Wang Gang Long Tao Jiang Shi Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第15期2338-2342,共5页
AIM: To compare the preservation of non-heart- beating donor (NHBD) livers in cold histidine-trytophan- ketoglutarate (HTK) solution and extracorporeal liver perfusion (ECLP). METHODS: Livers harvested from health pig... AIM: To compare the preservation of non-heart- beating donor (NHBD) livers in cold histidine-trytophan- ketoglutarate (HTK) solution and extracorporeal liver perfusion (ECLP). METHODS: Livers harvested from health pigs were stored for 10 h in cold HTK solution (group A, n = 4) or perfused with oxygenated autologous blood at body temperature (group B, n = 4). Both groups were then tested on the circuit for 4 h. Bile production, hemodynamic parameters, hepatocyte markers and reperfusion injury of extracorporeal livers were tested in each group. Liver tissues from each group were examined at the end of reperfusion. RESULTS: At 1, 2, 3 and 4 h after reperfusion, bile production, hemodynamic parameters, hepatocyte markers and reperfusion injury of livers in group A were statistically different from those in group B (P < 0.05 or P < 0.01). CONCLUSION: ECLP is better than HTK solution to preserve NHBD livers. ECLP can assess the graft viabilitybefore liver transplantation. 展开更多
关键词 Extracorporeal liver perfusion HistidineTrytophan-Ketoglutarate solution Non-heart-beatingdonor PRESERVATION
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Different known guard intervals for single/multi-carrier transceiver
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作者 李玮 程时昕 陈明 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期11-15,共5页
To enhance the bandwidth efficiency of the guard interval (GI) assisted wireless communication system, an attractive scheme is proposed, which combines the functions of pilots and the GI together, so that the pilot ... To enhance the bandwidth efficiency of the guard interval (GI) assisted wireless communication system, an attractive scheme is proposed, which combines the functions of pilots and the GI together, so that the pilot resource used for estimating channel state is saved. Based on the proposed different known guard intervals (DKGI), the time-domain channel estimation can be simply applied on the receiver side. After channel estimation, the receiver can employ the cyclic convolution restoring (CCR) function to reconstruct the cyclical convolution relationship between the signal and the channel, by which the receiver can also achieve good performance through the conventional 1-tap frequency domain equalization (FDE). 展开更多
关键词 cyclic prefix zero padding fixed symbol padding channel estimation
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XRCC1 and DNA polymerase β in cellular protection against cytotoxic DNA single-strand breaks 被引量:17
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作者 Julie K Horton Mary Watson +3 位作者 Donna F Stefanick Daniel T Shaughnessy Jack A Taylor Samuel H Wilson 《Cell Research》 SCIE CAS CSCD 2008年第1期48-63,共16页
Single-strand breaks (SSBs) can occur in cells either directly, or indirectly following initiation of base excision repair (BER). SSBs generally have blocked termini lacking the conventional 5'-phosphate and 3'-... Single-strand breaks (SSBs) can occur in cells either directly, or indirectly following initiation of base excision repair (BER). SSBs generally have blocked termini lacking the conventional 5'-phosphate and 3'-hydroxyl groups and require further processing prior to DNA synthesis and ligation. XRCC1 is devoid of any known enzymatic activity, but it can physically interact with other proteins involved in all stages of the overlapping SSB repair and BER pathways, including those that conduct the rate-limiting end-tailoring, and in many cases can stimulate their enzymatic activities. XRCC1^-/- mouse fibroblasts are most hypersensitive to agents that produce DNA lesions repaired by monofunctional glycosylase-initiated BER and that result in formation of indirect SSBs. A requirement for the deoxyribose phosphate lyase activity of DNA polymerase β (pol β) is specific to this pathway, whereas pol β is implicated in gap-filling during repair of many types of SSBs. Elevated levels of strand breaks, and diminished repair, have been demonstrated in MMS- treated XRCC1^-/-, and to a lesser extent in pol β^-/- cell lines, compared with wild-type cells. Thus a strong correlation is observed between cellular sensitivity to MMS and the ability of cells to repair MMS-induced damage. Exposure of wild-type and polβ^-/- cells to an inhibitor of PARP activity dramatically potentiates MMS-induced cytotoxicity. XRCC1^-/- cells are also sensitized by PARP inhibition demonstrating that PARP-mediated poly(ADP-ribosyl)ation plays a role in modulation of cytotoxicity beyond recruitment of XRCC 1 to sites of DNA damage. 展开更多
关键词 XRCC1 DNA polymerase β single-strand break repair base excision repair PARP inhibition
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HIGH RESOLUTION POSITIVITY-PRESERVING DIFFERENCE SCHEMES FOR TWO DIMENSIONAL EULER EQUATIONS
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作者 赵宁 张虎 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期163-168,共6页
A class of high resolution positivity preserving Boltzmann type difference schemes for one and two dimensional Euler equations is studied. First, the relation between Boltzmann and Euler equations is analyzed. By usi... A class of high resolution positivity preserving Boltzmann type difference schemes for one and two dimensional Euler equations is studied. First, the relation between Boltzmann and Euler equations is analyzed. By using a kind of special interpolation, the high resolution Boltzmann type difference scheme is constructed. Finally, numerical tests show that the schemes are effective and useful. 展开更多
关键词 Euler equation Boltzmann equation finite difference scheme positivity preserving
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Poverty Reduction,Environmental Protection and Ecosystem Services:A Prospective Theory for Sustainable Development 被引量:9
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作者 ZHEN Nahui FU Bojie +1 位作者 LU Yihe WANG Shuai 《Chinese Geographical Science》 SCIE CSCD 2014年第1期83-92,共10页
Poverty reduction and environmental protection are two global tasks for sustainable development.The study perspective has changed over time,from narrowly focusing on poverty reduction to comprehensively strengthening ... Poverty reduction and environmental protection are two global tasks for sustainable development.The study perspective has changed over time,from narrowly focusing on poverty reduction to comprehensively strengthening human-welfare.We reviewed key references targeting the theoretical content and practical approach relying on poverty,environment protection and ecosystem services.We discussed the contradicting views on the relationship of poverty and environmental degradation,and then illustrated the study progress of a cutting-age topic-ecosystem services which pave a way to address poverty reduction and environmental protection together.At last,we investigated essential factors that affect the development and environmental protection.Considering the evolution of the concept of poverty,we found that the environment has occupied an increasing proportion in the cognizance of poverty.The relationship between poverty and environmental degradation is regional uniqueness.In practical aspect,projects based on the management and valuation assessment of ecosystem services draw researchers′attention all over the world.The appropriate scale,essential economic incentives,morality,law and social equality are key factors affecting individuals′decisions which directly relate to the sustainable development. 展开更多
关键词 POVERTY environmental degradation ecosystem services sustainable development
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Bayesian prestack seismic inversion with a self-adaptive Huber-Markov random-field edge protection scheme 被引量:2
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作者 田玉昆 周辉 +2 位作者 陈汉明 邹雅铭 关守军 《Applied Geophysics》 SCIE CSCD 2013年第4期453-460,512,共9页
Seismic inversion is a highly ill-posed problem, due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling. To obtain a unique solution, some smoothing constraints, e.g., t... Seismic inversion is a highly ill-posed problem, due to many factors such as the limited seismic frequency bandwidth and inappropriate forward modeling. To obtain a unique solution, some smoothing constraints, e.g., the Tikhonov regularization are usually applied. The Tikhonov method can maintain a global smooth solution, but cause a fuzzy structure edge. In this paper we use Huber-Markov random-field edge protection method in the procedure of inverting three parameters, P-velocity, S-velocity and density. The method can avoid blurring the structure edge and resist noise. For the parameter to be inverted, the Huber- Markov random-field constructs a neighborhood system, which further acts as the vertical and lateral constraints. We use a quadratic Huber edge penalty function within the layer to suppress noise and a linear one on the edges to avoid a fuzzy result. The effectiveness of our method is proved by inverting the synthetic data without and with noises. The relationship between the adopted constraints and the inversion results is analyzed as well. 展开更多
关键词 Huber edge punishment function markov random-field bayesian framework prestack inversion
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Science Letters:A novel way of liver preservation improves rat liver viability upon reperfusion 被引量:5
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作者 KEBIS Anton KUKAN Marián +1 位作者 GRANI Peter JAKUBOVSK■ Ján 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第5期289-295,共7页
Background/aim: Currently, the liver is cold-preserved at 0-4 ℃ for experimental and clinical purposes. Here, we investigated whether milder hypothermia during the initial phase of the preservation period was benefi... Background/aim: Currently, the liver is cold-preserved at 0-4 ℃ for experimental and clinical purposes. Here, we investigated whether milder hypothermia during the initial phase of the preservation period was beneficial for liver viability upon reperfusion. Methods: In the first set of experiments, rat livers were preserved either conventionally in clinically used histidine-trypthopan-ketoglutarate (HTK) solution (Group A: 45 min and Group B: 24 h) or by slow cooling HTK solution (from 13 ℃ to 3 ℃) during the initial 45 min of preservation (Group C: 24 h). In the second set of experiments, additional groups of livers were evaluated: Group BB-preservation according to Group B and Group CC-preservation according to Group C. Further, some livers were preserved at 13 ℃ for 24 h. Livers were then reperfused using a blood-free perfusion model. Results: Bile production was approximately 2-fold greater in Group C compared to Group B. Alanine transaminase (ALT) and aspartate transaminase (AST) release into perfusate were 2-3-fold higher in Group B compared to Group C. No significant differences were found in ALT and AST release between Group C and Group A. Livers in Group CC compared to Group BB exhibited significantly lower portal resistance, greater oxygen consumption and bromosulfophthalein excretion into bile and lower lactate dehydrogenase (LDH) release into perfusate. Histological evaluation of tissue sections in Group BB showed parenchymal dystrophy of hepatocytes, while dystrophy ofhepatocytes was absent in Group CC. Livers preserved at 13 ℃ for 24 h exhibited severe ischemic injury Conclusion: These results suggest that the conventional way of liver preservation is not suitable at least for rat livers and that slow cooling of HTK solution during the initial phase of cold storage can improve liver viability during reperfusion. 展开更多
关键词 Rat Hepatic graft Cold ischemia Liver protection Histidine-trypthopan-ketoglutarate solution (HTK)
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A systematic review: How to choose appropriate health-related quality of life (HRQOL) measures in routine general practice? 被引量:2
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作者 陈天辉 李鲁 KOCHEN Michael M 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第9期936-940,共5页
In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must... In more recent times, health-related quality of life (HRQOL) measurements have formed an important part of as- sessing the quality of routine care in general practice. For a measure to have clinical usefulness it must not only be valid, appro- priate, reliable, responsive, and capable of being interpreted, but it must also be simple, fast to complete, easy to score, and provide useful clinical data. The Two-step method of choosing appropriate measures is introduced. Then through comparison of generic instruments with disease-specific instruments, we can conclude that sometimes a combination of generic and disease-specific HRQOL measures may be more appropriate for monitoring changes in a patient’s health status due to an intervention. 展开更多
关键词 Health-related quality of life (HRQOL) GENERIC Disease-specific MEASURE General practice
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