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“1+X”群文阅读教学及议题设置策略 被引量:1
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作者 马红 田园 《大连教育学院学报》 2023年第2期34-36,共3页
群文阅读是近年来广受关注的新型阅读教学模式。“1+X”群文阅读教学有三种模式:一篇课文带动多篇课文、一篇课文带动多篇课外文章、一个单元带动多篇课外文章。结合已有理论及课例和自身教学实践,“1+X”群文阅读教学议题设置应指向人... 群文阅读是近年来广受关注的新型阅读教学模式。“1+X”群文阅读教学有三种模式:一篇课文带动多篇课文、一篇课文带动多篇课外文章、一个单元带动多篇课外文章。结合已有理论及课例和自身教学实践,“1+X”群文阅读教学议题设置应指向人文主题、本体知识、阅读策略和思维认知。 展开更多
关键词 小学 群文阅读 议题
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龙血竭对辐射诱导的神经炎症的保护作用 被引量:2
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作者 张鹏 王海龙 +6 位作者 马宏 沈乾伟 孙飞一 陈钰 蓝钰 戴荣继 邓玉林 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2020年第8期762-767,共6页
深空探测的不断发展,潜在的战争威胁以及核事故的发生增加了人类辐射暴露的风险.神经炎症是人体在辐射暴露后重要生理反应之一.神经炎症的发生与神经退行性疾病如阿尔茨海默病(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease... 深空探测的不断发展,潜在的战争威胁以及核事故的发生增加了人类辐射暴露的风险.神经炎症是人体在辐射暴露后重要生理反应之一.神经炎症的发生与神经退行性疾病如阿尔茨海默病(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease,PD)密切相关.开发具有抗氧化和抗炎作用的中药对辐射引起的中枢神经系统损伤有积极意义.中药龙血竭对辐射诱导的神经炎症具有良好的治疗作用.本文总结了龙血竭在降低氧化应激水平,相关炎症因子表达和线粒体损伤中的作用.同时提出,内源性神经毒素可能加重辐射诱导的神经炎症的进程,而龙血竭可缓解这种神经炎症. 展开更多
关键词 龙血竭 辐射 活性氧 神经炎症 线粒体 内源性神经毒素
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Optoelectronic Detecting System for Inner Walls of Pipes 被引量:1
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作者 BAIBaoxing mahong 《Semiconductor Photonics and Technology》 CAS 1998年第2期104-108,共5页
This paper is concerned with a high characteristic image processing and recognition system that is used for inspecting real-time blemishes, streaks and cracks on the inner walls of high accuracy pipes. As a regular de... This paper is concerned with a high characteristic image processing and recognition system that is used for inspecting real-time blemishes, streaks and cracks on the inner walls of high accuracy pipes. As a regular detector, the BP neural network is used for extracting features of the image inspected and classifying these images, it takes fully advantage of the function of artificial neural network, such as the information distributed memory, large scale self-adapting parallel processing, high fault-tolerant ability and so forth. Besides, an improved BP algorithm is used in the system for training the network, and making the learning procedure of the net converges to the minimum of overall situation at high rate. 展开更多
关键词 光电子探测 抽运特性 图形识别 神经网络
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基于组合模型的区间模糊数时间序列预测模型 被引量:2
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作者 谢小军 马虹 +1 位作者 杨付贵 邱云兰 《阜阳师范大学学报(自然科学版)》 2020年第3期9-13,18,共6页
为对区间模糊数进行研究分析,本文首先将区间模糊数转换为等量信息的精确数序列,结合ARIMA模型和BP神经网络的优点,对转换后的精确数序列分别建立以ARIMA模型与BP神经网络的组合模型,最后区间模糊数序列的拟合值和预测值可利用还原公式... 为对区间模糊数进行研究分析,本文首先将区间模糊数转换为等量信息的精确数序列,结合ARIMA模型和BP神经网络的优点,对转换后的精确数序列分别建立以ARIMA模型与BP神经网络的组合模型,最后区间模糊数序列的拟合值和预测值可利用还原公式得到。文章以二元区间模糊数为研究对象,建立了以ARIMA模型与BP神经网络的组合模型。数值实验表明,该方法有效可行,预测精度要优于ARIMA模型。 展开更多
关键词 时间序列 区间模糊数 预测 组合模型
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涎腺恶性肿瘤中血管生成拟态的表达及临床意义
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作者 高琼 冯红超 +3 位作者 唐正龙 马洪 段晓峰 毛本源 《癌症进展》 2020年第1期51-54,79,共5页
目的探讨涎腺恶性肿瘤中血管生成拟态(VM)是否存在及其临床意义。方法采用CD31和PAS双重染色技术对43例涎腺恶性肿瘤组织及5例正常涎腺腺体组织进行CD31和PAS双重染色,探讨涎腺恶性肿瘤VM的结构形态,分析VM与腺样囊性癌临床分型的关系... 目的探讨涎腺恶性肿瘤中血管生成拟态(VM)是否存在及其临床意义。方法采用CD31和PAS双重染色技术对43例涎腺恶性肿瘤组织及5例正常涎腺腺体组织进行CD31和PAS双重染色,探讨涎腺恶性肿瘤VM的结构形态,分析VM与腺样囊性癌临床分型的关系。结果涎腺恶性肿瘤组织中存在VM结构,正常涎腺腺体组织中未见VM结构。43例涎腺恶性肿瘤组织中,8例(18.6%)存在VM结构,其中5例腺样囊性癌VM阳性,1例黏液表皮样癌VM阳性,1例多形性腺瘤VM阳性,1例肌上皮癌VM阳性;在光镜下观察可见VM结构为由肿瘤细胞围成的无内皮细胞衬附的管道样结构和PAS染色阳性的网络样VM结构,在肿瘤细胞和管腔间被一层PAS染色阳性物质间隔或被PAS阳性物质填充,部分病例中可见VM结构与相邻的CD31及PAS阳性血管相通,可在管腔中发现红细胞;涎腺恶性肿瘤组织中VM的数量与血管数量呈正相关(r=0.548,P﹤0.01);实质型腺样囊性癌组织中VM阳性率高于腺样-管状型腺样囊性癌组织,差异有统计学意义(P﹤0.05)。结论涎腺恶性肿瘤中存在VM,可为抗血管治疗提供新的靶点。 展开更多
关键词 涎腺恶性肿瘤 正常腺体组织 血管生成拟态 血管生成
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耦合最大熵和近邻传播聚类的城市空间多模式扩展元胞自动机模型构建 被引量:1
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作者 李启源 王海军 +2 位作者 周智勇 马红 柴洁 《地球信息科学学报》 EI CSCD 北大核心 2023年第7期1464-1480,共17页
多中心组团发展是优化区域空间结构的重要路径,由此带来的城市空间扩展模式包含邻接型与跳跃式,亟需研究顾及城市空间多模式扩展的模拟技术。既有研究难以较好实现跳跃式斑块的模拟,主要存在无法展现城市增长过程或选取的“扩展种子点... 多中心组团发展是优化区域空间结构的重要路径,由此带来的城市空间扩展模式包含邻接型与跳跃式,亟需研究顾及城市空间多模式扩展的模拟技术。既有研究难以较好实现跳跃式斑块的模拟,主要存在无法展现城市增长过程或选取的“扩展种子点”随机性过大或模型适用尺度较小等问题。本文提出了一种耦合最大熵模型(MaxEnt)与近邻传播聚类(AP)的MaxEnt-AP-CA模型:利用MaxEnt模型寻找跳跃式扩展备选区域并进行筛选,减小了种子点的搜寻范围,降低了随机性和运算数据量,适用于更大尺度;结合AP算法得到种子点,展现跳跃式斑块的增长过程;引入“生长系数”实现多模式扩展的同步模拟。以重庆市主城都市区为研究区,使用MaxEnt-AP-CA模拟了2010—2020年城市用地的扩展情况,研究发现:(1)MaxEnt-AP所求种子点命中实际跳跃式斑块的准确性显著提高;(2)在精度指标上,最优参数下,MaxEnt-AP-CA的FoM峰值达到0.3061,精度相比传统CA模型具有明显提高;景观形态上,MaxEnt-AP-CA在斑块规模、破碎度、聚集度上与实际情况更为接近,且能保留更多的斑块形状特征,最优模拟结果与实际城市的总体相似性为87.04%;局部细节特征上,MaxEnt-AP-CA可精准展现跳跃式增长斑块,能更准确地表达城市的真实扩展情况;(3)MaxEnt-AP-CA可兼顾多模式扩展模拟,契合我国城市发展现状,有助于推动构建新型城镇化格局。 展开更多
关键词 跳跃式扩展 多模式扩展 最大熵 近邻传播聚类 元胞自动机 地理模拟 城市扩展 多中心发展 重庆市
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Microvessel angiogenesis: a possible cardioprotective mechanism of external counterpulsation for canine myocardial infarction 被引量:12
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作者 WUGui-fu DUZhi-min +6 位作者 HUCheng-hen ZHENGZhen-sheng ZHANCheng-yang mahong FANGDian-qiu JohnCKHui WilliamELawson 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第14期1182-1189,共8页
Background Enhanced external counterpulsation (EECP) has been demonstrated to be effective in the treatment of patients with coronary artery disease (CAD). It has been proposed that the beneficial effects of EECP obse... Background Enhanced external counterpulsation (EECP) has been demonstrated to be effective in the treatment of patients with coronary artery disease (CAD). It has been proposed that the beneficial effects of EECP observed in clinical studies may be due to the formation of new blood vessels (angiogenesis) and collateral development. However, there is a relative paucity of basic studies to support the proposed mechanisms. Methods Twelve Beagle dogs were anesthetized with 3% sodium pentobarbital, 1 mg/kg intraperitoneal injection and mechanically ventilated for the development of myocardial infarction. After coronary occlusion, all animals were randomly assigned to either EECP or control. EECP was given one hour per day, 5 days a week, for a total of 28 to 30 hours treatment over a 6-week course. Immunohistochemical studies of alpha-actin and von Willebrand factor (vWF) were used to detect newly developed microvessels. Systemic and local vascular endothelial growth factor (VEGF) were identified by enzyme linked immunosorbent assay 9(ELISA) and reverse-transcriptional polymerase chain reaction (RT-PCR) analysis. Results There was a significant increase in the density of microvessels per mm(2) in the infarcted regions of EECP group compared to control group (vWF, 15.2 +/- 6.3 versus 4.9 +/- 2.1, P < 0.05; alpha-actin, 11.8 +/- 5.3 versus 3.4 +/- 1.2, P < 0.05), along with significant increase of positive vWF and a-actin stained area. Both immunohistochemical staining and RT-PCR analysis documented a significant increase in VEGF expression. These factors associated with angiogenesis corresponded to improved myocardial perfusion by Tc-99m-sestamibi single-photon emission computed tomography. 展开更多
关键词 ANGIOGENESIS collateral circulation growth factors INFARCTION ventricular function
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A test of Snowmelt Runoff Model(SRM)for the Gongnaisi River basin in the western Tianshan Mountains,China 被引量:10
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作者 mahong CHENGGuodong 《Chinese Science Bulletin》 SCIE EI CAS 2003年第20期2253-2259,共7页
The Snowmelt Runoff Model (SRM) is one of a very few models in the world today that requires remote sensing derived snow cover as model input. Owing to its simple data requirements and use of remote sensing to provide... The Snowmelt Runoff Model (SRM) is one of a very few models in the world today that requires remote sensing derived snow cover as model input. Owing to its simple data requirements and use of remote sensing to provide snow cover information, SRM is ideal for use in data sparse regions, particularly in remote and inaccessible high mountain watersheds. In order to verify the applicability of SRM in an environment of continental climate, a test of SRM is performed for the Gongnaisi River basin in the western Tianshan Mountains, the results show that two SRM average goodness-of-fit statistics for simulations, Nash-Sutcliff coefficient (R2) and volume difference (DV), are 0.87 and 0.90%, respectively. As compared with the application results over 80 basins in 25 different countries around the world, SRM performs well in the Gongnaisi River basin. The results also show that SRM can be a validated snowmelt runoff model capable of being applied in the western Tianshan Mountains. On the basis of snowmelt runoff simulation, together with a set of simplified hypothetical climate scenarios, SRM is also used to simulate the effects of climate change on snow cover and the consecutive snowmelt runoff. For a given hypothetical temperature increase of 4℃, the snow coverage and snowmelt season shift towards earlier dates, and the snowmelt runoff, as a result, is changed significantly at the same time. The simulation results show that the snow cover is sensitive to changes of climate, especially to the increase of temperature, the major effect of climate change will be a time shifting of snowmelt runoff to early spring months, resulting in a redistribution of seasonally runoff throughout the whole snowmelt season. 展开更多
关键词 中国 天山西部 融雪径流模型 遥感 积雪层 季节变化
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Genetic analysis and mapping of rice(Oryza sativa L.)male-sterile(OsMS-L)mutant 被引量:6
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作者 LIUHaisheng CHUHuangwei +11 位作者 LIHui WANGHonamei WEIJiali LINa DINGShuyan HUANGHai mahong HUANGChaofeng LUODa YUANGzheng LIUJianhua ZHANGDabing 《Chinese Science Bulletin》 SCIE EI CAS 2005年第2期122-125,共4页
A rice male-sterile mutant OsMS-L of japonica cultivar 9522 background, was obtained in M4 population treated with Co γ-Ray. Genetic analysis indicated that the 60 male-sterile phenotype was controlled by a single re... A rice male-sterile mutant OsMS-L of japonica cultivar 9522 background, was obtained in M4 population treated with Co γ-Ray. Genetic analysis indicated that the 60 male-sterile phenotype was controlled by a single recessive gene. Results of tissue section showed that at microspore stage, OsMS-L tapetum was retarded. Then tapetal cells ex- panded and microspores degenerated. No matured pollens were observed in OsMS-L anther locus. To map OsMS-L lo- cus, an F2 population was constructed from the cross be- tween the OsMS-L (japonica) and LongTeFu B(indica). Firstly, the OsMS-L locus was roughly mapped between two SSR markers, RM109 and RM7562 on chromosome 2. And then eleven polymorphic markers were developed for further fine fine-mapping. At last the OsMS-L locus was mapped between the two InDel markers, Lhs10 and Lhs6 with genetic distance of 0.4 cM, respectively. The region was delimited to 133 kb. All these results were useful for further cloning and functional analysis of OsMS-L. 展开更多
关键词 遗传分析 OsMS-L 突变异种 育种 基因图 分子标记 转基因作物
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Effect of angiotensin converting enzyme inhibitor on the calcium transients and calcium handling proteins in ventricular myocytes from rats with heart failure 被引量:2
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作者 WANGLi-chun mahong +11 位作者 HEJian-gui LIAOXin-xue CHENWen-fang LENGXiu-yu MALi MAIWei-yi TAOJun ZENGWu-tao LIUJun DONGYu-gang TANGAn-li FENGChong 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第9期731-737,共7页
Background Chronic heart failure (CHF) is associated with calcium transients and calcium handling proteins. Angiotensin converting enzyme (ACE) inhibitor has been demonstrated to have beneficial effect on CHF. Yet st... Background Chronic heart failure (CHF) is associated with calcium transients and calcium handling proteins. Angiotensin converting enzyme (ACE) inhibitor has been demonstrated to have beneficial effect on CHF. Yet studies addressed to the relationship between ACE inhibitor and calcium transients in CHF are rare. The aim of this study was to investigate the influence of ACE inhibitor (perindopril) on the contractility and calcium transients and calcium handling proteins in ventricular myocytes from rats with experimental heart failure.Methods Male Wistar rats were randomized to heart failure group treated with perindopril (CHF-T, 3 mg·kg -1 ·d -1 ), heart failure group without treatment (CHF-C) and sham-operated group (PS). Heart failure was induced by abdominal aortic constriction. All groups were further followed up for 12 weeks. Left ventricular myocytes were then isolated. Single cell shortening fraction and [Ca 2+ ]_i were simultaneously measured by laser scanning confocal microscope under the field stimulation (1.0 Hz). Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot were performed to evaluate the changes of mRNA and protein of Na +-Ca 2+ exchanger (NCX_1), sarcoplasmic reticulum Ca 2+ -ATPase (SERCA_2) and phospholamban (PLB).Results The fraction of cell shortening (FS%) and [Ca 2+ ]_ imax (nmol/L) were significantly reduced in group CHF-C compared with group PS (FS%: 7.51±1.15 vs 13.21±1.49;[Ca 2+ ]_ imax :330.85±50.05 vs 498.16±14.07; both P <0.01), and restored at least partially in CHF-T group. In CHF-C group, the left ventricular mRNA of NCX_1 and PLB were significantly upregulated in comparing with PS group (R_ NCX1/β-Actin : 0.51±0.12 vs 0.19±0.06, P <0.01; R_ PLB/β-Actin : 0.26±0.12 vs 0.20±0.08, P <0.05), while SERCA_2 mRNA was downregulated (0.48±0.10 vs 0.80±0.11, P <0.01). The mRNA levels of NCX_1 and SERCA_2 in CHF-T group were between the CHF-C and PS group, and the differences of the latter two groups were significant (all P <0.05). In CHF-C and CHF-T groups, the protein expression of NCX_1 were 1.141±0.047 and 1.074±0.081 times of that in PS group respectively (both P <0.05), and SERCA_2 protein levels were 0.803±0.100 and 0.893±0.084 times of that in PS group respectively (both P <0.05). The protein expression of NCX_1 and SERCA_2 in the CHF-C and CHF-T groups is significantly different (both P <0.05).ConclusionACE inhibitor could improve cardiac function of failing heart through directly enhancing the contractility of single cardiomyocyte, and these effects are probably mediated by its roles in preventing the deleterious changes of calcium transients and calcium handling proteins in CHF. 展开更多
关键词 angiotensin converting enzyme inhibitor · calcium transient · calcium handling protein · chronic heart failure · laser scanning confocal microscope
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