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利用地下流体观测井水位预测海南及邻区中强震发生时间 预览
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作者 解晓静 孙三健 +1 位作者 张慧 苏荣托雅 《地震地磁观测与研究》 2019年第3期120-130,共11页
利用海南地下流体观测井水位资料,选择适合长期、中短期地震异常提取方法,对海南及邻区M 4.0以上地震发生前水位异常进行分析,依据统计资料,提出预测海南及邻区中强震发生时间的指标与方法。
关键词 海南 井水位 地球物理异常 长期 中短期 地震预测
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The detrimental effects of lipopolysaccharideinduced neuroinflammation on adult hippocampal neurogenesis depend on the duration of the pro-inflammatory response 预览
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作者 Martha Pérez-Domínguez Evangelina Aila-Munz +1 位作者 Eduardo Domínguez-Rivas Angélica Zepeda 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第5期817-825,共9页
Adult hippocampal neurogenesis is a finely tuned process regulated by extrinsic factors.Neuroinflammation is a hallmark of several pathological conditions underlying dysregulation of neurogenesis.In animal models,lipo... Adult hippocampal neurogenesis is a finely tuned process regulated by extrinsic factors.Neuroinflammation is a hallmark of several pathological conditions underlying dysregulation of neurogenesis.In animal models,lipopolysaccharide(LPS)-induced neuroinflammation leads to a neurogenic decrease mainly associated to the early inflammatory response.However,it is not well understood how the neuroinflammatory response progresses over time and if neurogenesis continues to be diminished during the late neuroinflammatory response.Moreover,it is unknown if repeated intermittent administration of LPS along time induces a greater reduction in neurogenesis.We administered one single intraperitoneal injection of LPS or saline or four repeated injections(one per week)of LPS or saline to young-adult mice.A cohort of new cells was labeled with three 5-bromo-2-deoxyuridine injections(one per day)4 days after the last LPS injection.We evaluated systemic and neuroinflammation-associated parameters and compared the effects of the late neuroinflammatory response on neurogenesis induced by each protocol.Our results show that 1)a single LPS injection leads to a late pro-inflammatory response characterized by microglial activation,moderate astrocytic reaction and increased interleukin-6 levels.This response correlates in time with decreased neurogenesis and 2)a repeated intermittent injection of LPS does not elicit a late pro-inflammatory response although activated microglia persists.The latter profile is not accompanied by a continued longterm hippocampal neurogenic decrease.Hereby,we provide evidence that the neuroinflammatory response is a dynamic process that progresses in a milieu-dependent manner and does not necessarily lead to a neurogenic decrease,highlighting the complex interaction between the immune system and neurogenesis. 展开更多
关键词 DENTATE GYRUS subgranular zone inflammation microglia astrocytes IL-6 cytokines cell proliferation neural PROGENITOR cells IMMATURE neurons long-term short-term adult hippocampal NEUROGENESIS
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额颞蛛网膜囊肿认知功能障碍及其在神经内镜术后近期和远期的情况比较 预览
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作者 王金伟 欧益金 +3 位作者 穆林森 覃洁 胡凤兴 彭玉平 《广东医学》 CAS 2019年第11期1563-1567,共5页
目的探讨额颞蛛网膜囊肿(FTAC)认知功能障碍及其神经内镜术后近期和远期的改善情况。方法纳入29例FTAC手术(Ⅰ组)、16例FTAC非手术(Ⅱ组)、10例健康人(Ⅲ组)分别在术前2周(T1)、术后3个月(T2)、术后1年(T3)或相等的时间段间隔点进行认... 目的探讨额颞蛛网膜囊肿(FTAC)认知功能障碍及其神经内镜术后近期和远期的改善情况。方法纳入29例FTAC手术(Ⅰ组)、16例FTAC非手术(Ⅱ组)、10例健康人(Ⅲ组)分别在术前2周(T1)、术后3个月(T2)、术后1年(T3)或相等的时间段间隔点进行认知功能测验,采用重复测量方差分析比较评分;T1时3组量表评分行效度、信度检验,Ⅰ组和Ⅱ组额颞间、左右间评分均行t检验,颞叶囊肿不同Galassi分型间评分行方差分析。结果3组间评分差异有统计学意义(P<0.05),不同时间点间差异有统计学意义(P<0.05),存在交互作用(P<0.05):T1时Ⅰ组和Ⅱ组差异无统计学意义(P>0.05),但均差于Ⅲ组(P<0.05);T2或T3时Ⅰ组评分较T1改善(P<0.05)。T1时,效度检验因子载荷均>0.80,克朗巴赫系数0.70,额颞间评分差异无统计学意义(P>0.05),左侧抑制/转换测验评分差于右侧(P<0.05),不同Galassi分型间评分差异无统计学意义(P>0.05)。结论FTAC可引起基本和高级认知功能障碍;神经内镜术后认知功能改善,疗效长久稳定;认知功能障碍可作为术前考虑的手术适应证;左侧囊肿可能影响言语应变;囊肿大小与认知功能障碍缺少相关性。 展开更多
关键词 额颞蛛网膜囊肿 认知功能障碍 神经内镜 近期 远期
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医养结合在老年肺炎并支气管哮喘中的应用 预览
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作者 王艳 尹莉 《中国继续医学教育》 2019年第11期186-188,共3页
目的探讨长期医疗专护医养结合新模式在老年肺炎并发支气管哮喘患者中应用的效果。方法选取2015年1月—2017年1月我院收治的老年肺炎并发支气管哮喘患者86例为研究对象,将其随机分为两组。观察组(n=43)给予长期医疗专护医养结合新模式,... 目的探讨长期医疗专护医养结合新模式在老年肺炎并发支气管哮喘患者中应用的效果。方法选取2015年1月—2017年1月我院收治的老年肺炎并发支气管哮喘患者86例为研究对象,将其随机分为两组。观察组(n=43)给予长期医疗专护医养结合新模式,对照组(n=43)给予常规护理,对比两组患者护理前后两组患者用药依从性和哮喘控制情况以及护理满意度。结果护理后1个月、3个月,两组患者用药依从性均有所提高,且观察组患者提升更为明显,差异具有统计学意义(P<0.05)。治疗护理后1个月、3个月,两组患者哮喘控制评分均有所提高,但观察组患者提升更为明显,差异具有统计学意义(P<0.05)。观察组、对照组患者护理满意度分别为97.67%(42/43)、86.05%(37/43),组间比较,差异具有统计学意义(P<0.05)。结论长期医疗专护医养结合新模式可有效提高老年肺炎并发支气管哮喘患者的治疗依从性,有效控制哮喘情况。 展开更多
关键词 长期 医疗专护 医养结合 新模式 老年 肺炎并发支气管哮喘
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Development and validation of a model to determine risk of refractory benign esophageal strictures 预览
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作者 Qing Lu Tian-Tian Lei +5 位作者 Yi-Lan Wang Hai-Lin Yan Bo Lin Lin-Lin Zhu Hong-Sheng Ma Jin-Lin Yang 《世界临床病例杂志》 2019年第13期1623-1633,共11页
BACKGROUND Current research has identified several risk factors for refractory benign esophageal strictures (RBES), but research is scarce on the prediction of RBES in benign esophageal strictures patients. Meanwhile,... BACKGROUND Current research has identified several risk factors for refractory benign esophageal strictures (RBES), but research is scarce on the prediction of RBES in benign esophageal strictures patients. Meanwhile, the long-term outcomes of RBES remain unclear. The aim of this study was to develop and validate a model to determine the progression of RBES in patients with benign esophageal strictures. And we also explored the long-term outcomes and safety in patients with RBES. AIM To develop and validate a model to determine the progression of RBES in patients with benign esophageal strictures, based on the demographic data and endoscopic findings. METHODS A total of 507 benign esophageal stricture patients treated by dilation alone or in combination with stenting were retrospectively enrolled between January 2009 and February 2018. The primary outcome was to establish a risk-scoring model predicting RBES in benign esophageal strictures. The secondary outcome was to explore the clinical effectiveness and adverse events in patients with RBES. RESULTS In the study, age, etiology, and number and length of strictures were the independent risk factors for the refractory performance of benign esophageal strictures. According to risk factors of benign esophageal strictures, a risk-scoring model for predicting RBES in benign esophageal strictures was established: The risk score ranged from 0 to 8 points, and the risk scores were divided into low risk (0-2 points), intermediate risk (3-5 points), and high risk (6-8 points). The proportions of RBES in the corresponding risk categories were 1.0%, 12.2%, and 76.0%, respectively. Among 507 patients, 57 had RBES (39 males;median age, 60 years). The success rate of dilation treatment (51.2%, 21/41) was higher than that of stent placement (37.5%, 6/16). CONCLUSION In this study, 11.3%(57/507) patients had RBES at our hospital. The risk-scoring model predicting RBES in benign esophageal strictures could predict the longterm outcome of patients with strictures ahead. 展开更多
关键词 REFRACTORY BENIGN ESOPHAGEAL STRICTURES ESOPHAGEAL DILATION ESOPHAGEAL STENTS Long-term outcomes Retrospective analysis
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Diplomats On the Future of China-ASEAN Relations 预览
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《中国东盟报道》 2019年第2期40-43,共4页
In 2018, China and ASEAN celebrated the 15th anniversary of the China-ASEAN strategic partnership. Over the last 15 years, the two sides have cemented bilateral relations and stood shoulder-to-shoulder through thick a... In 2018, China and ASEAN celebrated the 15th anniversary of the China-ASEAN strategic partnership. Over the last 15 years, the two sides have cemented bilateral relations and stood shoulder-to-shoulder through thick and thin. The China-ASEAN Strategic Partnership Vision 2030 adopted by the 21st China-ASEAN Summit in November 2018 presented a new blueprint for the long-term growth of China-ASEAN relations in the new era. A goal has been set to build a closer community with a shared future. 展开更多
关键词 CHINA-ASEAN RELATIONS The BILATERAL RELATIONSHIP LONG-TERM growth
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Comparison of carbon sequestration efficiency in soil aggregates between upland and paddy soils in a red soil region of China 预览
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作者 LIU Kai-lou HUANG Jing +6 位作者 LI Da-ming YU Xi-chu YE Hui-cai HU Hui-wen HU Zhi-hua HUANG Qing-hai ZHANG Hui-min 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1348-1359,共12页
There is limited information on carbon sequestration efficiency(CSE)of soil aggregates in upland and paddy soils under long-term fertilization regimes.In a red soil region of southern China,an upland soil experiment s... There is limited information on carbon sequestration efficiency(CSE)of soil aggregates in upland and paddy soils under long-term fertilization regimes.In a red soil region of southern China,an upland soil experiment started in 1986 and a paddy soil experiment commenced in 1981.These experiments were conducted using different fertilization treatments.After 30 years,soil organic carbon(SOC)content and stock of different aggregate components were analyzed.The results showed that the SOC contents and stocks in upland soil were lower than in paddy soil.In both upland and paddy soils,the SOC contents and stocks of all aggregate components in NPKM(combined treatment with chemical nitrogen(N),phosphorus(P),potassium(K)fertilizers and manure)were the highest among all treatments.Compared with CK(no fertilizer),SOC content of all aggregate components in NPKM was increased by 13.21–63.11%and 19.13–73.33%in upland and paddy soils,respectively.Meanwhile,the change rates in SOC stock of all aggregate components in upland soil were lower than in paddy soil,although the change rate of SOC stock of all aggregate components in NPKM was higher than in other treatments.Furthermore,a linear equation could fit the relationships between carbon(C)input and change rate of SOC stock(P<0.05).Results indicated that the sum of CSE from all aggregate components in upland soil(16.02%)was higher than that of paddy soil(15.12%)in the same climatic condition and from the same parent material.However,the CSEs from all aggregates were higher than that of bulk soil,although the result from bulk soil also showed that the CSE of upland soil was higher than that of paddy soil. 展开更多
关键词 CSE SOC STOCK soil AGGREGATE C input long-term FERTILIZATION
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Using geophysical logs to identify Milankovitch cycles and to calculate net primary productivity(NPP) of the Late Permian coals,western Guizhou,China
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作者 Zhi-Ming Yan Long-Yi Shao +2 位作者 David Large Hao Wang Baruch Spiro 《古地理学报:英文版》 CSCD 2019年第1期31-42,共12页
Milankovitch periodicities of 123 kyr(eccentricity), 35.6 kyr(obliquity), and 21.2 kyr(precession) were identified in geophysical logs of three Late Permian coals: 17#, 18#, and 17 + 18#, from the Songhe mining area i... Milankovitch periodicities of 123 kyr(eccentricity), 35.6 kyr(obliquity), and 21.2 kyr(precession) were identified in geophysical logs of three Late Permian coals: 17#, 18#, and 17 + 18#, from the Songhe mining area in western Guizhou Province. Based on the astronomic temporal framework, the periods of deposition of the 17#(5.6 m), 18#(6.4 m), and 17 + 18#(5.4 m) coals were constrained to 140.8–119.8 kyr, 160–136.2 kyr, and 135–114.9 kyr,respectively. The overall depositional period of the 18# coal of 160–136.2 kyr was further subdivided using the wavelet analysis method, into short and precise periods corresponding to the Milankovitch periodicities. It includes one eccentricity periodicity(123 kyr), three obliquity periodicities(35.6 kyr), and five precession periodicities(21.2 kyr). Different thicknesses of the subdivided coal sections, equivalent to the same time span of deposition, indicate different rates of coal deposition, i.e., thicker sections imply higher rates while the thinner sections represent lower rates. The combination of the measured average carbon concentration with the density of the coals gave rise to long-term average values of carbon accumulation rates for the Late Permian coals, in the range of 42.4–50.6 g·C·m^-2·a^-1. This range corresponds to the long-term average carbon accumulation rates for the initial peat in the range of 60.6–72.3 g·C·m^-2·a^-1. Based on the known quantitative relation between net primary productivity(NPP)values and long-term average carbon accumulation rates for the Holocene tropical peatlands, the range of NPP values for the Late Permian tropical peatlands was estimated as 242.4–433.8 g·C·m^-2·a^-1.A comparison of existing information about peatland NPP levels of various ages and latitudes indicated that when conditions of high rain and high humidity prevail in the palaeo-peatland at given latitude, the NPP rates will vary with changes in atmospheric concentration of CO2 and O2. This relationship may lead to the use of coals as an indicator 展开更多
关键词 MILANKOVITCH cycle Coal deposition PEATLAND Long-term average carbon accumulation rate Net primary productivity Late PERMIAN GUIZHOU Province
从有效到长效:居民物业自主治理发展的逻辑转换 预览
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作者 王栋 《兰州学刊》 CSSCI 2019年第3期127-139,共13页
居民小区业主物业自治是对我国基层民主潜在的行政干预与行政载体体制下城乡社区自治范畴的颠覆。这种深刻而全新的变革模式对于未经过训练和洗礼的居民小区自治组织及业主带来了前所未有的挑战。面对挑战,消极对待的小区陷入治理困境,... 居民小区业主物业自治是对我国基层民主潜在的行政干预与行政载体体制下城乡社区自治范畴的颠覆。这种深刻而全新的变革模式对于未经过训练和洗礼的居民小区自治组织及业主带来了前所未有的挑战。面对挑战,消极对待的小区陷入治理困境,境况每况愈下。积极改革创新的小区虽然能够抵挡一时的困难,呈现出新的面貌,但很快又进入另一个二次困境之中。应该认真梳理这种困境循环的怪圈,不仅从内部运作机制,制度结构机制和技术操作机制等方面着手改善,更应该从社会环境、体制背景、文化处境等更为深刻、基础的层面全面协调。物业自治困境的摆脱不应限于当前的突破,而应着眼于未来持续健康发展的逻辑。 展开更多
关键词 居民小区 物业自主治理 有效 长效 发展逻辑
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FD2G催化裂化柴油加氢转化技术工业应用总结 预览
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作者 孙士可 曾榕辉 吴子明 《炼油技术与工程》 CAS 2019年第7期16-19,共4页
中国石油化工股份有限公司抚顺石油化工研究院开发的 FD2G 催化裂化柴油加氢转化技术已成功工业应用,在削减催化裂化柴油的同时,提高了汽油等高附加值产品的收率。开工初期,催化剂初期活性稳定后汽油产品的研究法辛烷值可以达到 90.0,... 中国石油化工股份有限公司抚顺石油化工研究院开发的 FD2G 催化裂化柴油加氢转化技术已成功工业应用,在削减催化裂化柴油的同时,提高了汽油等高附加值产品的收率。开工初期,催化剂初期活性稳定后汽油产品的研究法辛烷值可以达到 90.0,随着运行时间的延长,汽油产品的研究法辛烷值继续升高。通过工业应用结果分析了 FD2G 装置掺炼直馏柴油、重整重芳烃等原料的可行性,以及掺炼不同原料对汽油产品性质的影响。通过工艺条件的优化,在运行中末期逐渐提高反应压力可以有效延缓催化剂失活速率,精制反应器最高点温度提温速率为 0.004 0 ~ 0.008 5 ℃/d,转化反应器最高点温度提温速率为 0. 003 2 ~ 0. 004 4 ℃/d,实现了工业装置的长周期运行,运行周期不低于 36 个月。 展开更多
关键词 FD2G 工业应用 催化裂化柴油 高辛烷值汽油 长周期
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Paired associative stimulation improves synaptic plasticity and functional outcomes after cerebral ischemia 预览
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作者 Yan Hu Tie-Cheng Guo +2 位作者 Xiang-Yu Zhang Jun Tian Yin-Shan Lu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第11期1968-1976,共9页
Paired associative stimulation is a relatively new non-invasive brain stimulation technique that combines transcranial magnetic stimulation and peripheral nerve stimulation. The effects of paired associative stimulati... Paired associative stimulation is a relatively new non-invasive brain stimulation technique that combines transcranial magnetic stimulation and peripheral nerve stimulation. The effects of paired associative stimulation on the excitability of the cerebral cortex can vary according to the time interval between the transcranial magnetic stimulation and peripheral nerve stimulation. We established a model of cerebral ischemia in rats via transient middle cerebral artery occlusion. We administered paired associative stimulation with a frequency of 0.05 Hz 90 times over 4 weeks. We then evaluated spatial learning and memory using the Morris water maze. Changes in the cerebral ultra-structure and synaptic plasticity were assessed via transmission electron microscopy and a 64-channel multi-electrode array. We measured mRNA and protein expression levels of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1 in the hippocampus using a real-time polymerase chain reaction and western blot assay. Paired associative stimulation treatment significantly improved learning and memory in rats subjected to cerebral ischemia. The ultra-structures of synapses in the CA1 area of the hippocampus in rats subjected to cerebral ischemia were restored by paired associative stimulation. Long-term potentiation at synapses in the CA3 and CA1 regions of the hippocampus was enhanced as well. The protein and mRNA expression of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1 increased after paired associative stimulation treatment. These data indicate that paired associative stimulation can protect cog-nition after cerebral ischemia. The observed effect may be mediated by increases in the mRNA and protein expression of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1, and by enhanced synaptic plasticity in the CA1 area of the hippocampus. The animal experiments were approved by the Animal Ethics Committee of Tongji Medical College, Huazhong University of Science & Technology, China(appr 展开更多
关键词 cerebral ischemia paired ASSOCIATIVE stimulation cognitive function long-term POTENTIATION SYNAPTIC plasticity Morris water maze SYNAPTIC structure N-methyl-D-aspartic acid receptor BRAIN-DERIVED NEUROTROPHIC factor MULTI-ELECTRODE array neural regeneration
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长期小剂量罗红霉素与阿奇霉素治疗稳定期COPD的临床对比研究 预览
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作者 王蓓 刘冬 许西琳 《中国现代医药杂志》 2019年第6期34-37,共4页
目的研究长期应用小剂量罗红霉素与小剂量阿奇霉素在稳定期COPD患者维持治疗中的疗效。方法 60例COPD患者随机分为罗红霉素组20例,阿奇霉素组20例和对照组20例。在常规治疗基础上,罗红霉素组每天口服一次小剂量罗红霉素150mg,阿奇霉素... 目的研究长期应用小剂量罗红霉素与小剂量阿奇霉素在稳定期COPD患者维持治疗中的疗效。方法 60例COPD患者随机分为罗红霉素组20例,阿奇霉素组20例和对照组20例。在常规治疗基础上,罗红霉素组每天口服一次小剂量罗红霉素150mg,阿奇霉素组每天口服一次小剂量阿奇霉素125mg,对照组仅给予常规治疗,疗程为1年。各组患者均允许吸氧,常规治疗吸入糖皮质激素、支气管扩张剂和长效β受体激动剂。同时比较三组FEV1、FEV1/FVC、6min步行距离、呼吸困难评分、生活质量评分、加重发作频率(人/年)和用药不良反应情况。结果罗红霉素组累计急性发作频率为3个月7次,6个月10次,12个月14次;阿奇霉素组累计急性加重频率为3个月5次,6个月8次,12个月10次;对照组累计急性发作频率3个月10次,6个月15次,12个月24次,三组间对比差异无统计学意义(P>0.05)。罗红霉素组与阿奇霉素组患者在FEV1/FVC(%)、6min步行距离、呼吸困难评分、PaO2、PaCO2和痰量上均较对照组有较明显改善。结论长期口服小剂量阿奇霉素和罗红霉素效果安全有效,可改善肺功能、缓解呼吸困难、延缓气道重塑,改善COPD患者生活质量。 展开更多
关键词 罗红霉素 阿奇霉素 COPD 小剂量 长期
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基于长时间序列遥感数据的鄱阳湖水面面积监测分析 预览
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作者 张文 崔长露 +2 位作者 李林宜 贾祎琳 孟令奎 《水文》 CSCD 北大核心 2019年第3期29-35,21共8页
国产高分辨率卫星的快速发展可有效弥补遥感湖泊监测中影像分辨率不足的问题,更加及时、准确地实现湖泊动态监测。利用1996~2012年155景Landsat影像和2013~2016年34景GF影像为数据源,结合湖口站水位监测数据,分别选用改进的归一化差异... 国产高分辨率卫星的快速发展可有效弥补遥感湖泊监测中影像分辨率不足的问题,更加及时、准确地实现湖泊动态监测。利用1996~2012年155景Landsat影像和2013~2016年34景GF影像为数据源,结合湖口站水位监测数据,分别选用改进的归一化差异水体指数MNDWI和归一化差异水体指数NDWI方法提取卫星遥感影像的水体信息,同时采用统计分析的方法建立了4个时间段的鄱阳湖水体面积-水位关系模型。结果表明:在空间上,鄱阳湖水体面积整体呈现缓慢缩小的趋势;在时间上,除秋季鄱阳湖面积有明显下降趋势外,其他季节整体趋势变化不大;经验证,鄱阳湖四季水体面积-水位呈现二次函数关系。 展开更多
关键词 遥感 长时间序列 水位 水体面积 鄱阳湖
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二甲双胍改善长期体外培养骨髓间充干细胞的增殖和分化功能 预览
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作者 章淑艳 倪德胜 王维戚 《实用口腔医学杂志》 CAS CSCD 北大核心 2019年第3期345-350,共6页
目的:观察二甲双胍(metfomin, Met)能否改善体外长期培养小鼠骨髓间充质干细胞(BMMSCs)的增殖和成骨分化功能。方法:分离小鼠BMMSCs进行体外培养,选取P1代和P6代细胞,P6代细胞用Met处理,检测细胞增殖,克隆形成,ALP活性、矿化结节和成骨... 目的:观察二甲双胍(metfomin, Met)能否改善体外长期培养小鼠骨髓间充质干细胞(BMMSCs)的增殖和成骨分化功能。方法:分离小鼠BMMSCs进行体外培养,选取P1代和P6代细胞,P6代细胞用Met处理,检测细胞增殖,克隆形成,ALP活性、矿化结节和成骨基因mRNA表达水平。使用试剂盒检测细胞ROS水平,并检测抗氧化、干细胞属性(干性)及衰老相关基因的mRNA表达情况。结果:小鼠P6代BMMSCs的增殖和成骨分化功能明显低于P1代细胞,Met可以显著提高P6代细胞的增殖和成骨分化能力,并提高细胞的抗氧化功能和干性,降低衰老相关基因表达。结论:Met能够增强体外长期培养的小鼠BMMSCs的增殖和分化功能,这种作用可能是通过改善氧化应激和提高干性实现的。 展开更多
关键词 骨髓间充质干细胞(BMMSCs) 长期培养 二甲双胍 增殖 成骨分化
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农村订单定向医学生基层执业意愿及影响因素分析——以云南省为例 预览
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作者 李伟明 黄兴黎 +5 位作者 袁丹 张永光 姜润生 黄巧云 孙美娜 自蓉 《中国卫生政策研究》 CSCD 北大核心 2019年第5期76-81,共6页
目的:以云南省为例,分析农村订单定向医学生的基层长期执业意愿及影响因素,为促进订单定向医学生基层长期执业提供依据。方法:采取分层整群抽样方法,对云南省3所高等院校的1 673名农村订单定向医学生进行问卷调查,内容包括个人基本情况... 目的:以云南省为例,分析农村订单定向医学生的基层长期执业意愿及影响因素,为促进订单定向医学生基层长期执业提供依据。方法:采取分层整群抽样方法,对云南省3所高等院校的1 673名农村订单定向医学生进行问卷调查,内容包括个人基本情况、政策认知和态度、报考动因、执业意愿等,共收集有效问卷1 613份。采用多重响应、卡方检验、二元Logistic回归等方法进行数据分析。结果:83.51%的医学生了解免费培养政策,87.85%的医学生支持免费培养政策,仅有35.46%的医学生愿意在基层长期执业;就读年级、政策认知、政策态度、为家乡人民服务、想当全科医生、个人职业发展有限、个人婚姻问题、工作待遇低等变量对订单定向医学生基层长期执业意愿有显著影响。结论:订单定向医学生扎根基层的长期执业意愿不强。应基于人才培养定位,强化专业认同培养,重视职业素质培育,创建良好职业发展环境。 展开更多
关键词 订单定向医学生 执业意愿 影响因素 农村 长期
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Numerical simulation of sedimentation process in reservoirs and development of a non-coupled algorithm to improve long-term modeling 预览
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作者 Zeinab Khorrami Mohammad Ali Banihashemi 《国际泥沙研究:英文版》 SCIE 2019年第3期279-294,共16页
This paper investigates the validity of a quasi-steady approximation for sediment transport and presents a new algorithm based on this concept.The developed non-coupled algorithm interacts among hydrodynamic,sediment,... This paper investigates the validity of a quasi-steady approximation for sediment transport and presents a new algorithm based on this concept.The developed non-coupled algorithm interacts among hydrodynamic,sediment,and morphology modules which are based on depth-averaged Navier-Stokes equations for the flow,the three-dimensional equation of conservation of sediment,and the mass balance between the bed and sediment(Exner equation)to simulate the reservoir sedimentation process.The non-coupled algorithm solves both the short-term scale and the relatively long-term scale problems of reservoir sedimentation.The proposed algorithm is verified using field data and by comparison with other accurate algorithms.Based upon the results of this investigation,the developed algorithm can be used to simulate long-term reservoir sedimentation while considerably decreasing the computational costs and preserving computational accuracy.The computational cost of the noncoupled algorithm is about 97% less than the conventional semi-coupled approach whereas the errors(Root Mean Square Error,Average Relative Error,and Maximum Relative Error of bed level)of the developed algorithm are approximately 15% greater than those for the semi-coupled algorithm for the average value. 展开更多
关键词 LONG-TERM simulation RESERVOIR Coupling ALGORITHM SEDIMENT and morphology Non-coupled Semi-coupled
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Long-term adaptive informative path planning for scalar field monitoring using cross-entropy optimization
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作者 Yang LI Rongxin CUI +1 位作者 Weisheng YAN Demin XU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第5期26-28,共3页
Dear editor,Robots are extensively used in various civil and military applications (1, 2)In the last decade, informative path planning (IPP) has been one of the most important research areas in modern robot engineerin... Dear editor,Robots are extensively used in various civil and military applications (1, 2)In the last decade, informative path planning (IPP) has been one of the most important research areas in modern robot engineering [3], especially in long-term monitoring of a particular area of interest. 展开更多
关键词 LONG-TERM ADAPTIVE INFORMATIVE path planning for scalar field MONITORING using CROSS-ENTROPY OPTIMIZATION exp length
Economic Analysis of Port and PICC in Long-term Intravenous Administration for Malignant Tumor Patients in Chinese Oncology Hospital Setting 预览
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作者 陶立波 靳勇 +3 位作者 蒋理添 陈丽萍 白旭明 王剑 《世界中西医结合杂志(英文)》 2019年第2期52-57,共6页
OBJECTIVE: To calculate and compare the cost of Port and PICC’s application in long-term intravenous administration, and to support the decision making of hospital manager. METHODS: Literature review and patient surv... OBJECTIVE: To calculate and compare the cost of Port and PICC’s application in long-term intravenous administration, and to support the decision making of hospital manager. METHODS: Literature review and patient survey in 2 oncology centers in China were carried out to investigate the cost and impact of Port and PICC for patients. The cost at different time of intravenous administration was calculated and compared. One-way sensitivity analysis was performed and tornado graph was drawn. RESULTS: Direct cost of Port at 0.5, 1, 1.5, and 2 years were7442, 8005, 8553, and 9131 CNY, and 4700, 9399, 14032, 18799 CNY for PICC respectively. Direct & indirect cost at 0.5, 1, 1.5, and 2 years were 9291, 11704, 14101, 16529 CNY for Port and 9697, 19393, 29023, 38787 CNY for PICC. Sensitivity analysis showed that productivity loss and device maintenance cost were the most in?uential factors to the result. CONCLUSION: Port had higher cost in short term and less in long term compared with PICC. Patients expected to get intravenous administration more than 0.5 year should use Port if both direct and indirect costs were included. 展开更多
关键词 LONG-TERM intravenous administration IMPLANTABLE CENTRAL VENOUS PORT Peripherally inserted CENTRAL catheter Cost
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裂解气压缩机长周期运行举措 预览
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作者 李元明 于洋 +3 位作者 张勇 刘国刚 朱景刚 吴恙 《当代化工》 CAS 2019年第2期427-430,共4页
裂解气压缩机作为乙烯装置最关键核心机组,如果出现故障将严重后果。由于裂解气中富含1,3丁二烯、苯乙烯、环戊二烯等多种易结焦组分,将对压缩机的正常运行产生严重危害。对压缩机长周期运行中出现的异常问题进行分析,并提出了相对可行... 裂解气压缩机作为乙烯装置最关键核心机组,如果出现故障将严重后果。由于裂解气中富含1,3丁二烯、苯乙烯、环戊二烯等多种易结焦组分,将对压缩机的正常运行产生严重危害。对压缩机长周期运行中出现的异常问题进行分析,并提出了相对可行的解决建议。 展开更多
关键词 裂解气压缩机 长周期 结焦
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Response of soil Olsen-P to P budget under different long-term fertilization treatments in a fluvo-aquic soil 预览
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作者 ZHANG Wei-wei ZHAN Xiao-ying +2 位作者 ZHANG Shu-xiang Khalid Hamdan Mohamed Ibrahima XU Ming-gang 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第3期667-676,共10页
The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P a... The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, China, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg–1 for every 100 kg ha–1 of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha–1, soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg–1, respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha–1 of P surplus. When P surplus was higher than the range of 729–884 kg ha–1, soil Olsen-P increased by 49.0 and 37.0 mg kg–1 in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha–1 P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the 'storage threshold' of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha–1P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased and that of summer maize could be decreased based 展开更多
关键词 long-term FERTILIZATION fluvo-aquic SOIL OLSEN-P P BUDGET critical SOIL P value
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