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设施番茄产量品质及土壤有效养分的影响——基于不同节水灌溉方案 预览
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作者 王琴 张星星 +3 位作者 王洁 林志远 谢修会 侯毛毛 《农机化研究》 北大核心 2020年第7期186-190,共5页
为明晰不同节水灌溉措施和灌溉量对土壤-作物系统的影响,以设施番茄为植物材料,设计不同灌水模式(喷灌、滴灌和浇灌)及不同灌溉定额(140、180、220 m~3/hm~2),观测不同处理下番茄总产量、叶面积指数(LAI)、果实品质、土壤盐分及有效养... 为明晰不同节水灌溉措施和灌溉量对土壤-作物系统的影响,以设施番茄为植物材料,设计不同灌水模式(喷灌、滴灌和浇灌)及不同灌溉定额(140、180、220 m~3/hm~2),观测不同处理下番茄总产量、叶面积指数(LAI)、果实品质、土壤盐分及有效养分等指标。结果表明:相比浇灌处理,滴灌和喷灌增产效果明显,在相同灌水量条件下滴灌优于喷灌,滴灌处理番茄总产量达到118.3~138.7t/hm~2;相同灌水模式下,较低的灌水量有利于番茄可溶性固形物、总糖和Vc含量的增加。高灌水量有利于耕层土壤盐分的去除,不同灌水模式以滴灌效果最佳。此外,滴灌、喷灌等节水灌溉措施形成的土壤干湿交替的状态有利于肥料元素的矿化,可提高耕层土壤有效养分水平。 展开更多
关键词 节水灌溉 灌溉量 土壤 番茄 产量
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Inhibiting endogenous tissue plasminogen activator enhanced neuronal apoptosis and axonal injury after traumatic brain injury 预览
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作者 Jun-Jie Zhao Zun-Wei Liu +4 位作者 Bo Wang Ting-Qin Huang Dan Guo Yong-Lin Zhao Jin-Ning Song 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期667-675,共9页
Tissue plasminogen activator is usually used for the treatment of acute ischemic stroke,but the role of endogenous tissue plasminogen activator in traumatic brain injury has been rarely reported.A rat model of traumat... Tissue plasminogen activator is usually used for the treatment of acute ischemic stroke,but the role of endogenous tissue plasminogen activator in traumatic brain injury has been rarely reported.A rat model of traumatic brain injury was established by weight-drop method.The tissue plasminogen activator inhibitor neuroserpin(5μL,0.25 mg/mL)was injected into the lateral ventricle.Neurological function was assessed by neurological severity score.Neuronal and axonal injuries were assessed by hematoxylin-eosin staining and Bielschowsky silver staining.Protein level of endogenous tissue plasminogen activator was analyzed by western blot assay.Apoptotic marker cleaved caspase-3,neuronal marker neurofilament light chain,astrocyte marker glial fibrillary acidic protein and microglial marker Iba-1 were analyzed by immunohistochemical staining.Apoptotic cell types were detected by immunofluorescence double labeling.Apoptotic cells in the damaged cortex were detected by terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP-biotin nick-end labeling staining.Degenerating neurons in the damaged cortex were detected by Fluoro-Jade B staining.Expression of tissue plasminogen activator was increased at 6 hours,and peaked at 3 days after traumatic brain injury.Neuronal apoptosis and axonal injury were detected after traumatic brain injury.Moreover,neuroserpin enhanced neuronal apoptosis,neuronal injury and axonal injury,and activated microglia and astrocytes.Neuroserpin further deteriorated neurobehavioral function in rats with traumatic brain injury.Our findings confirm that inhibition of endogenous tissue plasminogen activator aggravates neuronal apoptosis and axonal injury after traumatic brain injury,and activates microglia and astrocytes.This study was approved by the Biomedical Ethics Committee of Animal Experiments of Shaanxi Province of China in June 2015. 展开更多
关键词 apoptosis ASTROCYTES AXONAL INJURY inflammation microglia nerve REGENERATION neural REGENERATION neuronal INJURY neurons NEUROSERPIN tissue PLASMINOGEN activator traumatic brain INJURY
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脊柱矫形后发生近端交界性后凸危险因素的荟萃分析 预览
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作者 张健 王小健 +4 位作者 秦德安 赵中涛 梁庆元 安奇君 宋洁富 《中国组织工程研究》 CAS 北大核心 2020年第3期460-468,共9页
背景:对于实施脊柱畸形矫形的患者,近端交界性后凸是术后常见的并发症,可导致成年人和青少年脊柱畸形患者多种不良临床预后。因此,有必要对可能导致矫形术后患者发生近端交界性后凸的危险因素进行分析,以扩大对近端交界性后凸的认识并... 背景:对于实施脊柱畸形矫形的患者,近端交界性后凸是术后常见的并发症,可导致成年人和青少年脊柱畸形患者多种不良临床预后。因此,有必要对可能导致矫形术后患者发生近端交界性后凸的危险因素进行分析,以扩大对近端交界性后凸的认识并为预防其发生提供指导。目的:通过荟萃分析评价影响脊柱畸形矫形术后发生近端交界性后凸畸形的危险因素。方法:在PubMed、EMbase、Cochrane、中国知网和万方医学检索截止至2019年5月发表的公开文献,严格评价文献质量,根据纳入标准和排除标准选择文献,收集相关数据,使用Rev Man5.3软件统计分析相关数据,评估荟萃分析结果。结果与结论:①共纳入26篇文献,总计4498例患者,其中921例患者术后发生近端交界性后凸,经分析后显示脊柱矫形术后近端交界性后凸发生率为25%;②年龄,体质量指数,骨质疏松,手术椎体数量,最上端固定椎体至胸腰段(T10-L1),最下端固定椎体固定至骶骨/骨盆/髂骨,术后近端交界区后凸角、腰椎前凸角和矢状面垂直偏移,术前术后近端交界区后凸角变化、腰椎前凸角变化和矢状面垂直偏移变化,以上指标在近端交界性后凸患者和非近端交界性后凸患者之间差异有显著性意义(P <0.05);③而性别、截骨、前后联合手术、术前近端交界区后凸角、术前腰椎前凸角在近端交界性后凸患者和非近端交界性后凸患者之间差异无显著性意义(P> 0.05);④该荟萃分析显示,非手术因素中高龄、体质量指数、骨质疏松;手术因素中固定节段> 5个椎体,最上端固定内固定至胸腰段,最下端固定至骶骨/骨盆/髂骨,术后近端交界区后凸角、腰椎前凸角、矢状面垂直偏移,术前术后近端交界区后凸角、腰椎前凸角、矢状面垂直偏移变化较大是近端交界性后凸发生的主要危险因素。可通过干预高危人群及手术方案的制定,降低近端� 展开更多
关键词 脊柱矫形 近端交界性后凸 畸形 危险因素 荟萃分析 国家自然科学基金
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1,25(OH)2D3干预糖尿病肾病模型大鼠肾脏组织MicroRNA-130b及 转化生长因子β1的变化 预览
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作者 刘玥彤 王琴 +2 位作者 杨烨 朱筠 阿布力克木·吐尔地 《中国组织工程研究》 CAS 北大核心 2020年第2期248-253,共6页
背景:1,25(OH)2D3在糖尿病肾病的发展过程中发挥着重要调节作用。目的:探索1,25(OH)2D3对糖尿病肾病大鼠肾脏组织MicroRNA-130b及转化生长因子β1表达的影响作用。方法:实验方案经新疆医科大学动物实验中心动物实验伦理委员会批准。将2... 背景:1,25(OH)2D3在糖尿病肾病的发展过程中发挥着重要调节作用。目的:探索1,25(OH)2D3对糖尿病肾病大鼠肾脏组织MicroRNA-130b及转化生长因子β1表达的影响作用。方法:实验方案经新疆医科大学动物实验中心动物实验伦理委员会批准。将25只清洁级SD大鼠随机分为正常对照组、糖尿病肾病+1,25(OH)2D3组、糖尿病肾病+花生油组,后2组分别给予骨化三醇(即1,25(OH)2D3,活性维生素D3)0.03μg/(kg?d)治疗、花生油对照处理。37 d后采集标本,以实时聚合酶链式反应(RT-PCR)、Western blot及免疫组织化学方法检测大鼠肾脏组织转化生长因子β1的表达;RT-PCR检测MicroRNA-130b的表达;采用苏木精-伊红及Masson染色对大鼠肾脏形态结构及纤维化程度进行分析。结果与结论:①RT-PCR结果显示,糖尿病肾病+1,25(OH)2D3组及糖尿病肾病+花生油组MicroRNA-130b的表达明显低于正常对照组(P<0.01),糖尿病肾病+1,25(OH)2D3组明显高于糖尿病肾病+花生油组(P<0.01);②RT-PCR、Western blot、免疫组织化学及病理结果显示,糖尿病肾病+1,25(OH)2D3组及糖尿病肾病+花生油组转化生长因子β1 mRNA和蛋白的表达、大鼠肾脏组织结构紊乱及纤维化程度明显高于正常对照组(P<0.01),糖尿病肾病+1,25(OH)2D3组明显低于糖尿病肾病+花生油组(P<0.01);③结果说明,糖尿病肾病大鼠肾脏MicroRNA-130b表达水平下降,转化生长因子β1 mRNA及蛋白表达水平升高,肾脏组织结构紊乱及纤维化程度严重;1,25(OH)2D3可上调糖尿病肾病大鼠肾脏MicroRNA-130b的表达水平,同时还可下调糖尿病肾病大鼠肾脏转化生长因子β1的表达水平,改善肾脏组织结构紊乱及纤维化程度。 展开更多
关键词 糖尿病肾病 SPF级SD大鼠 链脲佐菌素 肾脏纤维化 1 25(OH)2D3 MicroRNA-130b 转化生长因子Β1
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Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Evidence for the decays of ∧c^+→∑^+η and ∑^+η’
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作者 麦迪娜 M.N.Achasov +146 位作者 S.Ahmed M.Albrecht M.Aleksee A.Amoroso 安芬芬 安琪 白羽 O.Bakina R. Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 O.Cakir A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈平亮 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 段鹏飞 范荆州 方建 房双世 方易 R.Farinelli L.Fava S.Fegan F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 T.Hussain N.Hu sken W.Ikegami Andersson M.Irshad 纪全 姬清平 季晓斌 季筱璐 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson A.Julin N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kornicer M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kuhn J.S.Lange P.Larin L.La 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期15-23,共9页
We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII col... We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays ∧^+→∑^+η and ∑^+η' and with statistical significance of and , respectively. Normalizing to the reference decays ∧^+→∑^+π^0 and ∑^+ω, we obtain the ratios of the branching fractions B(∧C^+→∑^+η)/V(∧^→∑^+π^0)and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)to be and , respectively. The upper limits at the 90% confidence level are set to be B(∧C^→∑^+η)/V(∧^+→∑^+π^0)<0.58 and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)<1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(∧C^+→∑^+η)=(0.41±019±0.05)%(<0.68%) and B(∧C^+→∑^+η)=(1.34+0.53+0.19)%(<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of ∧C^+→∑^+η is consistent with the previous measurement, and the branching fraction of ∧C^+→∑^+η is measured for the first time. 展开更多
关键词 charmed BARYON ∧c^+ DECAYS branching FRACTIONS
临床试验机构能力评估系列标准
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作者 洪明晃 王少华 +47 位作者 程金莲 王海英 赵秀丽 黄建英 吴建才 王敏 王豪 张黎 方翼 王洪允 所伟 曲恒燕 刘利军 丁雪鹰 丁倩 阎昭 王焕玲 林阳 周焕 郝晓花 吴伟 余勤 白桦 汪秀琴 曹国英 王美霞 王晓霞 梁雁 曹玉 元唯安 张弛 孙浩 沈瑛 付海鸿 薛华丹 郭韶洁 张洋 黄琳 武峰 金娟 杨柳 朱卫国 刘真 陈锐 王瓅珏 刘巧 韩冕 曹彩 《药物评价研究》 CAS 2019年第6期1041-1060,共20页
临床试验机构能力评估系列标准包括临床试验机构能力评估标准、伦理委员会审查能力评估标准、临床试验专业组能力评估标准、Ⅰ期临床试验能力评估标准、生物样本分析检测能力评估标准。既可以综合对临床试验机构进行整体评估,也可以独... 临床试验机构能力评估系列标准包括临床试验机构能力评估标准、伦理委员会审查能力评估标准、临床试验专业组能力评估标准、Ⅰ期临床试验能力评估标准、生物样本分析检测能力评估标准。既可以综合对临床试验机构进行整体评估,也可以独立进行单项评估。标准中同时规定了评估结果判定方式。以期能够切实促进临床试验机构的规范化运行与监管,促进临床试验机构及临床试验从业人员自律,加速我国临床试验研究国际化进程,提升临床试验研究与管理水平。 展开更多
关键词 临床试验 能力评估 标准
Intravitreal conbercept injection for neovascular agerelated macular degeneration
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作者 Bing-Hui Wu Bing Wang +2 位作者 Hui-Qin Wu Qin Chang Hui-Qin Lu 《国际眼科杂志:英文版》 SCIE CAS 2019年第2期252-257,共6页
AIM:To evaluate the efficacy and safety of intravitreal injection of conbercept in patients with neovascular agerelated macular degeneration(AMD). METHODS:Retrospective review of 66 eyes of 63 patients with neovascula... AIM:To evaluate the efficacy and safety of intravitreal injection of conbercept in patients with neovascular agerelated macular degeneration(AMD). METHODS:Retrospective review of 66 eyes of 63 patients with neovascular AMD. All patients received 0.5 mg intravitreal injections of conbercept monthly for 3 consecutive months, and then pro re nata treatment was performed. The changes of best-corrected visual acuity(BCVA) and central macular thickness(CMT) were observed before and after treatments. Minimum follow-up time was 12 mo. SPSS 22.0 statistical software was used for statistical analysis. RESULTS:The mean BCVA and CMT of 66 eyes(63 patients) were 1.11±0.60, 533.20±219.95 μm at baseline, and were 0.68±0.38, 310.28±125.60 μm at 3 mo. No subjects were lost during the first three months, the improvements were all significantly(P<0.05). During the whole follow-up time of 12 mo, 15 subjects(18 eyes) were lost. The mean BCVA and CMT of the rest 48 eyes with the follow-up time at least 1 y were 0.83±0.46 and 547.59±196.77 μm at baseline, after 3 mo and 12 mo of conbercept injections became 0.55±0.41, 318.24±141.29 μm and 0.55±0.51, 333.87±173.25 μm. The differences were significant(P<0.05). No serious complications were observed. CONCLUSION:Intravitreal injection of conbercept appears to significantly improve visual acuity and anatomical outcomes in patients with neovascular AMD, no serious adverse reactions and complications are observed. 展开更多
关键词 AGE-RELATED MACULAR DEGENERATION INTRAVITREAL INJECTION conbercept
Climate Trends of Temperature, Precipitation and River Discharge in the Abbay River Basin in Ethiopia 预览
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作者 Asaminew Abiyu Cherinet Denghua Yan +8 位作者 Hao Wang Xinshan Song Tianlin Qin Mulualem T. Kassa Abel Girma Batsuren Dorjsuren Mohammed Gedefaw Hejia Wang Otgonbayar Yadamjav 《水资源与保护(英文)》 2019年第10期1292-1311,共20页
Projecting future changes of streamflow in the Abby River Basin (ARB) is important for planning and proper management of the basin system. The current study conducted in five stations of the Abbay river basin, and inv... Projecting future changes of streamflow in the Abby River Basin (ARB) is important for planning and proper management of the basin system. The current study conducted in five stations of the Abbay river basin, and investigated the annual temperature, precipitation, and river discharge variability using the Innovative trend analysis method, Mann-Kendall, and Sen’s slope test estimator. The result showed a slightly increasing trend of annual precipitation in Assoa (Z = 0.71), Bahir Dar (Z = 0.13), and Gonder (Z = 0.26) stations, while a significant increasing trend was observed in Nedgo (Z = 2.45) and Motta (Z = 1.06) stations. Interestingly, the trend of annual temperature in Assosa (Z = 5.88), Bahir Dar (Z = 3.87), Gonder (Z = 4.38), Nedgo (Z = 4.77), and Motta (Z = 2.85) was abruptly increased. The average mean temperature has increased by 0.2°C in the past 36 years (1980 to 2016). The extreme high temperature was observed in the semi-dry zone of northern Ethiopia. During the study period, a significant declining trend of the river discharge was recorded, and the river discharge was sharply decreased from 1992 onwards. The results of the current study showed annual variability of river discharge, precipitation, and temperature of the study area of the basin that could be used as a basis for future studies. 展开更多
关键词 Abbay RIVER BASIN Climate Change Ethiopia PRECIPITATION RIVER DISCHARGE TEMPERATURE
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Effect of Adding Walnut Powder on Physical and Chemical Properties of Wheat Flour and Preventing Hyperlipidemia in Mice 预览
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作者 Gill Ali Abrar Fanrui Zhao +3 位作者 Hanxiong Qin Ji Wang Chunlei Liu Weihong Min 《食品与营养科学(英文)》 2019年第7期776-792,共17页
Walnuts (Juglans regia L.) are naturally rich source of many important nutrients which could be helpful in different food processing. Walnut mainly containing polyunsaturated fatty acids (PUFA), especially alpha linol... Walnuts (Juglans regia L.) are naturally rich source of many important nutrients which could be helpful in different food processing. Walnut mainly containing polyunsaturated fatty acids (PUFA), especially alpha linoleic acid (18:3n-3;9 g) and linoleic acid (18:3n-;38 g). Walnuts powder was fortified with commercial high gluten wheat flour (WF) into 4 composites flour from 10% to 40%. Walnut flour improves the nutritional value due to high protein and fat content, but affects the technological properties. Parameters such as functional, pasting and rheological properties demonstrated the influence of walnut reincorporation into gluten network. The interaction of walnut flour with wheat flour is a key factor which effects on the dough quality, causing thinning and weakening the gluten structure. Flour with 30% to 40% walnut substitution was more nutritious especially in relation to protein and monounsaturated fatty acid (MUFA), but responsible for more changes in technological characteristics of dough. Present study was also directed to examine the effect of moderate walnut consumption on lipids profile, enzymatic anti-oxidant (superoxide dismutase SOD and glutathione peroxidase GSH-Px) and lipid peroxidation (Melondialdehyde MDA) in rats fed with high-fat food. The Sprague Dawley rats were housed for five weeks and assembled into normal, high fat, high fat (HF) + 10% walnut, HF + 20% walnut, HF + 30% walnut and HF + 40% walnut. The lipid profile significantly improved especially by lowering the low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) level increased in the group of HF + 40% walnut. The total anti-oxidant, SOD and GSH-Px activity were increased by supplementation of walnut and significantly higher in HF + 40% compared to the normal group. The Melondialdehyde (MDA) or lipid peroxidation status was increased in HF + 20% walnut to HF + 30% walnut as compared to normal and HF-fed diet but reduced by HF + 40% walnut. These results suggest that walnut intake could be e 展开更多
关键词 WALNUT PASTING PROPERTIES Rheological PROPERTIES LIPIDS Enzymatic ANTI-OXIDANT LIPIDS Peroxidation
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Quantitative Characterization and Dynamic Law of Interlayer Interference for Multilayer Commingled Production in Heavy Oil Reservoirs by Numerical Simulation 预览
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作者 Dong Liu Fengyi Zhang +2 位作者 Qin Zhu Xinran Wang Jing Fan 《世界工程和技术(英文)》 2019年第3期379-395,共17页
This paper moves one step forward to build?a?numerical model to research quantitative characterization and dynamic law for interlayer interference factor (IIF) in the multilayer reservoir which was heavy oil reservoir... This paper moves one step forward to build?a?numerical model to research quantitative characterization and dynamic law for interlayer interference factor (IIF) in the multilayer reservoir which was heavy oil reservoirs and produced by directional wells. There are mainly four contributions of this paper to the existing body of literature. Firstly, an equivalent simulation method of the pseudo start pressure gradient (PSPG) is developed to quantitatively predict the value of?IIF?under different geological reservoir conditions. Secondly, the interlayer interference is extended in time, and the time period of the study extends from a water cut stage to the whole process from the oil well open to produce?a?high water cut. Thirdly, besides the conventional productivity interlayer interference factor (PIIF), a new parameter, that is, the oil recovery interlayer interference factor (RIIF) is put forward.?RIIF?can be used to evaluate the technical indexes of stratified development and multilayer co-production effectively. Fourthly,?the?effectsof various geological reservoir parameters such as reservoir permeability and crude oil viscosity, etc. on the?PIIF?and?RIIF’s?type curves?are?discussed in detail and the typical plate?is?plotted. The research results provide a foundation for the effective development of multilayer heavy oil reservoirs. 展开更多
关键词 Heavy Oil INTERLAYER Interference MULTILAYER Commingled PRODUCTION PSEUDO START Pressure Gradient Water FLOODING
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凝固速度对超高铬高碳双相钢组织及性能的影响
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作者 王琴 王桂芹 +2 位作者 车宏龙 李亚军 雷明凯 《材料保护》 CAS CSCD 北大核心 2019年第9期1-10,共10页
目前对超高铬高碳双相钢的凝固过程及凝固组织研究较少。采用化学分析法、金相和扫描电镜观察、电子探针显微分析、X射线衍射分析对熔模和金属模铸造1.5%C-40%Cr超高铬高碳双相不锈钢的成分、铸态及热处理态的组织和结构进行了研究。结... 目前对超高铬高碳双相钢的凝固过程及凝固组织研究较少。采用化学分析法、金相和扫描电镜观察、电子探针显微分析、X射线衍射分析对熔模和金属模铸造1.5%C-40%Cr超高铬高碳双相不锈钢的成分、铸态及热处理态的组织和结构进行了研究。结果显示:熔模铸造超高铬高碳钢的凝固过程为先析出δ铁素体枝晶,随后是(δ+M23C6)共晶,再在δ枝晶周围形成包晶γ,最后形成菊花状(γ+M23C6)共晶,其中δ铁素体在后续冷却中转变为(γ2+σ)共析。金属模铸造时,先析出δ铁素体枝晶和少量(δ+M23C6)共晶,再析出δ枝晶周围的包晶γ和网状(γ+M23C6)共晶。熔模、金属模铸造双相钢的固溶处理组织均由铁素体-奥氏体基体和M23C6碳化物组成。与金属模相比,熔模铸造时,超高铬高碳双相钢固溶处理态的硬度略微降低,抗拉强度、断裂韧性、耐磨和耐蚀性能都略有提高。 展开更多
关键词 凝固速度 超高铬高碳双相钢 显微组织 力学性能 耐磨抗蚀性能
低强度超声辐照对人宫颈癌HeLa细胞凋亡及Casepase-12蛋白表达的影响 预览
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作者 秦娟 宋国林 +4 位作者 王建三 林虹 刘卿 陈锦云 王嫣 《贵州医科大学学报》 CAS 2019年第10期1161-1166,共6页
目的:探讨低强度超声辐照对人宫颈癌HeLa细胞凋亡及半胱氨酸天冬氨酸特异性蛋白酶-12(Casepase-12)蛋白表达的影响。方法:采用低强度超声辐照人子宫颈癌HeLa细胞株,于辐照后6及24h时,AnnexinV/PI双染法检测HeLa细胞的凋亡率,透射电子显... 目的:探讨低强度超声辐照对人宫颈癌HeLa细胞凋亡及半胱氨酸天冬氨酸特异性蛋白酶-12(Casepase-12)蛋白表达的影响。方法:采用低强度超声辐照人子宫颈癌HeLa细胞株,于辐照后6及24h时,AnnexinV/PI双染法检测HeLa细胞的凋亡率,透射电子显微镜观察细胞的结构变化,Westernblot法测定细胞匀浆中Caspase-12蛋白表达水平,免疫组织化学法检测Caspase-12蛋白在HeLa细胞中的阳性表达率。结果:低强度超声辐照后6h时HeLa细胞的凋亡率、细胞Caspase-12蛋白表达水平及Caspase-12蛋白在HeLa细胞中的阳性表达率显著高于对照组,差异有统计学意义(P<0.05);辐照后24h时变化更显著,差异有统计学意义(P<0.01);透射电子显微镜下可见,辐照后6h时HeLa细胞内开始出现凋亡小体,24h时胞浆浓缩、内质网变疏松并与胞膜融合、形成空泡;辐照后6h及24h时,Caspase-12蛋白在HeLa细胞胞浆中表达、呈棕黄色颗粒,但在对照组细胞中无表达。结论:低强度超声辐照可以诱导人宫颈癌HeLa细胞凋亡,并随着辐照后时间延长而增加,其机制可能与相关凋亡蛋白Caspase-12表达水平上调有关。 展开更多
关键词 超声多普勒 低强度 宫颈癌 HeLa细胞 细胞凋亡 凋亡蛋白 半胱氨酸天冬氨酸特异性蛋白酶-12 免疫组织化学法
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Bioinformatics Analysis of the Interaction between Coat Protein and Nuclear Shuttle Protein in <i>Babuvirus</i> 预览
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作者 Naitong Yu Jianhua Wang +3 位作者 Naixin Yu Xiaobao Zheng Qin Zhou Zhixin Liu 《美国植物学期刊(英文)》 2019年第4期622-630,共9页
Protein and protein interactions play important roles in many biological processes and are responsible for carrying out the function of biological regulatory network in living organisms. Previous study indicated that ... Protein and protein interactions play important roles in many biological processes and are responsible for carrying out the function of biological regulatory network in living organisms. Previous study indicated that Banana bunchy top virus (BBTV) coat protein (CP) interacted with BBTV nuclear shuttle protein (NSP). However, the protein and protein interaction and the binding affinity of CP and NSP in Babuvirus are remaining unclear. In this study, the CPs and NSPs proteins of BBTV, Abaca bunchy top virus (ABTV) and Cardamom bushy dwarf virus (CBDV) were used for bioinformatic analysis. The binding free energy and the dissociation constant of the possible interaction proteins were tested in PPA-Pred2, and the results confirmed CP interaction with NSP in Babuvirus. The study will help us to understand the interaction between viral protein and viral protein, and the pathogenesis mechanism of Babuvirus in host plants. 展开更多
关键词 Babuvirus Coatprotein NUCLEAR SHUTTLE PROTEIN Interaction BIOINFORMATICS Analysis
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黄酒对健康大鼠肥胖相关指标的影响 预览
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作者 王丽媛 秦文 +5 位作者 霍军生 卓勤 杨倬 王晶波 沈葹 李岩 《中国酿造》 CAS 北大核心 2019年第5期27-30,共4页
研究黄酒对健康大鼠肥胖指标体质量、血脂及肠道菌群的影响。24只健康雄性SD大鼠,随机分为黄酒组、酒基对照组和空白对照组,分别给予黄酒、15%酒基和蒸馏水,连续灌胃35 d后,测定体质量增量、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白... 研究黄酒对健康大鼠肥胖指标体质量、血脂及肠道菌群的影响。24只健康雄性SD大鼠,随机分为黄酒组、酒基对照组和空白对照组,分别给予黄酒、15%酒基和蒸馏水,连续灌胃35 d后,测定体质量增量、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)含量及肠道菌群多样性。结果表明,黄酒对大鼠体质量增加及血脂指标没有显著影响(P≥0.05)。高通量测序结果显示,黄酒能够上调拟杆菌门并下调厚壁菌门组成比例;能够上调双歧杆菌属(Bifidobacterium)、嗜粘蛋白-艾克曼菌属(Akkermansia muciphila)和拟杆菌属(Bacteroides)组成比例。物种α-多样性分析结果显示,黄酒对大鼠肠道菌群多样性没有显著影响(P≥0.05)。在实验周期内,黄酒有抑制大鼠体质量增加的趋势,可能与能够调节肥胖有关的肠道菌群比例有关。 展开更多
关键词 黄酒 体质量 血脂 肠道菌群
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Experimental Study on Influencing Factors of Resistance Coefficient and Residual Resistance Coefficient in Oilfield Z 预览
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作者 Xinran Wang Lizhen Ge +2 位作者 Dong Liu Qin Zhu Bin Zheng 《世界工程和技术(英文)》 2019年第2期270-281,共12页
In order to clarify the major influence factors of resistance coefficient and residual resistance coefficient, so as to provide the basis for optimizing the polymer flooding schemes in oilfield Z of Bohai Sea, artific... In order to clarify the major influence factors of resistance coefficient and residual resistance coefficient, so as to provide the basis for optimizing the polymer flooding schemes in oilfield Z of Bohai Sea, artificial cores were made by simulated the characteristic parameters of real reservoir and the spacing of production-injection wells. The main parameters considered include reservoir permeability, polymer solution concentration and polymer injection rate. Core experiment of polymer flooding was taken by considering all the main parameters. The result showed that resistance coefficient and residual resistance coefficient decrease with the increase of core permeability. Resistance coefficient and residual resistance coefficient increase with the increase of concentration of polymer solution. The increment of displacement pressure in low permeability core is higher than in medium and high permeability core. The resistance coefficient increase with higher displacing velocity, and the increment in high permeability core is higher than in low permeability?core. The displacement velocity has little effect on the residual resistance coefficient. The experimental results can effectively guide the formulation of polymer flooding scheme in offshore oilfields, and optimize the appropriate injection rate and concentration of polymer solution for different properties of reservoirs, thus ensuring the effectiveness of polymer flooding in offshore oilfields. 展开更多
关键词 RESISTANCE COEFFICIENT RESIDUAL RESISTANCE COEFFICIENT Polymer FLOODING Laboratory Experiment OFFSHORE OILFIELD
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Research and Application of Water Flooding Timing and Method for Blocky Bottom Water Fractured Buried Hill Reservoir 预览
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作者 Xiaolin Zhu Hui Cai +2 位作者 Xinran Wang Qin Zhu Zhiqiang Meng 《电力能源(英文)》 2019年第9期1-10,共10页
Oilfield A is a fractured buried hill reservoir in Bohai bay of China. In order to solve the difficult problem of water flooding timing and method in oilfield. Considering the characteristics of the buried hill fractu... Oilfield A is a fractured buried hill reservoir in Bohai bay of China. In order to solve the difficult problem of water flooding timing and method in oilfield. Considering the characteristics of the buried hill fractures with stress sensitivity and strong heterogeneity, the ECLIPSE software was used in the research, and a three-dimensional injection-production numerical model for horizontal wells in buried hill reservoirs is established. According to the main research factors in water flooding, a series of water flooding schemes are designed, and the optimization of water flooding timing, oil recovery rate and water flooding mode in buried hill reservoirs were carried out. The results show that the optimum pressure level of fractured reservoir is about 70% of the original reservoir pressure. The optimal water flooding method is the conventional water flooding in the initial stage, when the water cut reaches 80%, it is converted into periodic water flooding. The oil recovery is the highest when the water injection period is 4 months. Field tests show that conventional water flooding is carried out in the initial stage of the oilfield A when the pressure is reduced to 70% of the original. Periodic water flooding is carried out when water cut is 80%. Good development results had been achieved in the 10 years since oilfield A was put into production. The average productivity of single well reached 300 m3/d in the initial stage, at present, the water cut is 60%, and the recovery degree is 18.5%, which is better than that of similar oilfields. This technology improves the water flooding effect of blocky bottom water fractured dual media reservoirs in metamorphic buried hills, and provides a reference for the development of similar reservoirs. 展开更多
关键词 Fractured BURIED HILL Reservoir WATER FLOODING TIMING WATER FLOODING METHOD Numerical Simulation
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斑点叉尾鮰Cbx基因家族的全基因组鉴定与进化分析
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作者 张世勇 陈校辉 +6 位作者 王明华 钟立强 秦钦 邵俊杰 刘洪岩 王江 边文冀 《基因组学与应用生物学》 CAS CSCD 北大核心 2019年第4期1488-1496,共9页
利用Cbx家族基因高度保守的Chromo结构域氨基酸序列作为种子序列,检索斑点叉尾鮰(Ictalurus punetaus)基因组注释的蛋白数据库,共鉴定分离出14个Cbx基因。并在全基因组水平对斑点叉尾鮰Cbx基因家族进行了保守结构域序列、进化、基因结... 利用Cbx家族基因高度保守的Chromo结构域氨基酸序列作为种子序列,检索斑点叉尾鮰(Ictalurus punetaus)基因组注释的蛋白数据库,共鉴定分离出14个Cbx基因。并在全基因组水平对斑点叉尾鮰Cbx基因家族进行了保守结构域序列、进化、基因结构、染色体定位的系统分析。本研究中鉴定出的斑点叉尾鮰Cbx家族基因蛋白序列与已知的人类、小鼠、鸡、斑马鱼等物种Cbx蛋白序列构建系统进化树。根据系统进化树分析结果,14个斑点叉尾鮰Cbx基因分成两个亚族,5个隶属于Hp1s亚族,9个隶属于PcGs亚族。Cbx基因主要分布于斑点叉尾鮰7条染色体中,且呈不均匀分布。本研究对于后续斑点叉尾鮰Cbx基因家族深入的功能验证及分子作用机制研究具有重要的意义,也为日益丰富的水产基因组资源的挖掘利用提供了参考。 展开更多
关键词 斑点叉尾鮰 Cbx基因 Chromo结构域 基因家族
原子荧光法测汞过程中仪器管路污染清洗方法的研究
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作者 王琴 王新建 +1 位作者 刘妍 秦娜娜 《医学动物防制》 2019年第8期777-779,共3页
目的研究一种能够快速方便地解决原子荧光测汞管路污染问题的清洗液。方法对模拟污染源进行原子荧光检测后,分别用3种不同的清洗液进行清洗效果比较;同时用不同温度、不同浓度的重铬酸钾硝酸溶液进行清洗效果的比较。结果对同一浓度50 n... 目的研究一种能够快速方便地解决原子荧光测汞管路污染问题的清洗液。方法对模拟污染源进行原子荧光检测后,分别用3种不同的清洗液进行清洗效果比较;同时用不同温度、不同浓度的重铬酸钾硝酸溶液进行清洗效果的比较。结果对同一浓度50 ng/ml的模拟污染源进行检测,用10%硝酸溶液和50℃的热浓硝酸溶液各清洗5次,空白荧光强度下降不是很明显;而用0. 05%重铬酸钾-硝酸溶液冲洗两次后,空白荧光强度由10 965. 32下降至147. 76,清洗效果显著。用20℃、30℃、40℃和50℃的0. 05%重铬酸钾-硝酸溶液清洗,50℃重铬酸钾硝酸溶液空白荧光强度下降更快。用0. 2 g/L、0. 5 g/L、1. 0 g/L、1. 5 g/L、2. 0 g/L重铬酸钾硝酸溶液进行清洗,随着浓度的增大,空白荧光强度变化不大。结论 0. 05%重铬酸钾-硝酸溶液能够快速降低标准空白荧光强度,有效地解决了原子荧光汞管路污染的问题。 展开更多
关键词 原子荧光法 管路污染 清洗方法
新型病毒衣壳结合剂哌嗪新衍生物抑制肠道病毒71型的复制
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作者 杨倬 王晶波 +3 位作者 秦文 王丽媛 卓勤 田波 《中国微生态学杂志》 CAS CSCD 2019年第7期776-780,共5页
目的研究哌嗪新衍生物体外对肠道病毒71型(EV71)的抑制作用。方法培养EV71感染的人横纹肌肉瘤RD细胞,建立体外病毒感染模型,将哌嗪新衍生物作用于RD细胞,通过Western blot、Real-time PCR和病毒滴度检测细胞内EV71病毒蛋白和mRNA的表达... 目的研究哌嗪新衍生物体外对肠道病毒71型(EV71)的抑制作用。方法培养EV71感染的人横纹肌肉瘤RD细胞,建立体外病毒感染模型,将哌嗪新衍生物作用于RD细胞,通过Western blot、Real-time PCR和病毒滴度检测细胞内EV71病毒蛋白和mRNA的表达水平及培养基上清中子代病毒颗粒的数量;并且观察细胞病变效应(CPE),采用CCK-8法检测哌嗪新衍生物对细胞活性的影响。结果哌嗪新衍生物VP1-4浓度为5μg/mL能够显著抑制RD细胞中EV71 VP1蛋白的表达,EV71 mRNA水平降低了(93.8±3.1)%,IC50约为0.016μg/mL,培养基上清病毒滴度降低了(51.1±0.8)%;而且VP1-4能够减缓EV71病毒感染引起的CPE。此外,化合物VP1-4 CC50>200μg/mL,说明细胞毒性低,安全性较高。结论本研究证实VP1-4能有效抑制EV71的复制,可以作为先导化合物开展进一步研究。 展开更多
关键词 肠道病毒71型 哌嗪新衍生物 RD细胞 抑制
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