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Identification of a novel coronavirus causing severe pneumonia in human:a descriptive study 被引量:113
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作者 Li-Li Ren Ye-Ming Wang +33 位作者 Zhi-Qiang Wu Zi-Chun Xiang Li Guo teng Xu Yong-Zhong Jiang Yan Xiong Yong-Jun Li Xing-Wang Li hui Li Guo-hui Fan Xiao-Ying Gu Yan Xiao Hong Gao Jiu-Yang Xu Fan Yang Xin-Ming Wang Chao Wu Lan Chen Yi-Wei Liu Bo Liu Jian Yang Xiao-Rui Wang Jie Dong Li Li Chao-Lin Huang Jian-Ping Zhao Yi Hu Zhen-Shun Cheng Un-Lin Liu Zhao-hui Qian Chuan Qin Qi Jin Bin Cao Jian-Wei Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第9期1015-1024,共10页
Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,... Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,we report a novel batorigin CoV causing severe and fatal pneumonia in humans.Methods:We collected clinical data and bronchoalveolar lavage(BAL)specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital,Hubei province,China.Nucleic acids of the BAL were extracted and subjected to next-generation sequencing.Virus isolation was carried out,and maximum-likelihood phylogenetic trees were constructed.Results:Five patients hospitalized from December 18 to December 29,2019 presented with fever,cough,and dyspnea accompanied by complications of acute respiratory distress syndrome.Chest radiography revealed diffuse opacities and consolidation.One of these patients died.Sequence results revealed the presence of a previously unknownβ-CoV strain in all five patients,with 99.8%to 99.9%nucleotide identities among the isolates.These isolates showed 79.0%nucleotide identity with the sequence of SARS-CoV(GenBank NC_004718)and 51.8%identity with the sequence of MERS-CoV(GenBank NC_019843).The virus is phylogenetically closest to a bat SARS-like CoV(SL-ZC45,GenBank MG772933)with 87.6%to 87.7%nucleotide identity,but is in a separate clade.Moreover,these viruses have a single intact open reading frame gene 8,as a further indicator of bat-origin CoVs.However,the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV,indicating that these viruses might use the same receptor.Conclusion:A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans. 展开更多
关键词 Bat-origin CORONAVIRUS Zoonotic transmission PNEUMONIA ETIOLOGY Next-generation sequencing
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注射用醋酸亮丙瑞林微球联合腹腔镜对子宫内膜异位症患者血清TIMP-1 MMP-9水平及受孕率的影响 被引量:47
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作者 章琼 滕慧 +3 位作者 胡玉利 嵇晓红 吴元赭 郝群 《河北医学》 CAS 2019年第5期726-732,共7页
目的:探讨注射用醋酸亮丙瑞林微球联合腹腔镜对子宫内膜异位症患者血清基质金属蛋白酶-9(MMP-9)及基质金属蛋白酶抑制剂-1(TIMP-1)水平、受孕率的影响。方法:选取我院子宫内膜异位症患者98例(2014年12月至2017年3月),根据治疗方案分为... 目的:探讨注射用醋酸亮丙瑞林微球联合腹腔镜对子宫内膜异位症患者血清基质金属蛋白酶-9(MMP-9)及基质金属蛋白酶抑制剂-1(TIMP-1)水平、受孕率的影响。方法:选取我院子宫内膜异位症患者98例(2014年12月至2017年3月),根据治疗方案分为对照组(n=49)与研究组(n=49)。对照组采取腹腔镜保守手术,研究组于对照组基础上加用醋酸亮丙瑞林微球(1次/4周,共注射6次)。统计两组临床疗效、治疗前后性激素指标[黄体生成素(LH)、孕激素(P)、卵泡刺激素(FSH)、雌二醇(E2)]水平、血清MMP-9及TIMP-1水平、MMP-9/TIMP-1、治疗前及治疗后1个月雌激素状态所致绝经症状评分(Kupperman)及盆腔疼痛程度分值(VAS),并随访9~12个月,统计两组受孕率。结果:①临床疗效:研究组总有效率93.88%(46/49)高于对照组79.59%(39/49)(P<0.05);②性激素指标:两组治疗后血清LH、P、FSH、E2水平低于治疗前,且研究组低于对照组(P<0.05);③血清MMP-9及TIMP-1:两组治疗后血清MMP-9及TIMP-1水平及MMP-9/TIMP-1较治疗前降低,且研究组低于对照组(P<0.05);④Kupperman及VAS分值:两组治疗后1个月Kupperman及VAS分值较治疗前降低,且研究组低于对照组(P<0.05);⑤受孕率:治疗后9个月、12个月研究组受孕率(36.73%、51.02%)高于对照组(18.37%、28.57%)(P<0.05)(P<0.05)。结论:采取注射用醋酸亮丙瑞林微球联合腹腔镜治疗子宫内膜异位症,可有效改善其血清性激素含量,降低血清MMP-9及TIMP-1水平,调节MMP-9/TIMP-1平衡,缓解临床症状及疼痛感,改善疾病整体治疗效果,且利于提高受孕率,对改善患者预后效果具有一定积极意义。 展开更多
关键词 醋酸亮丙瑞林微球 腹腔镜 子宫内膜异位症 TIMP-1 MMP-9 受孕率
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Engineering a New Chloroplastic Photorespiratory Bypass to In crease Photosynthetic Efficiency and Productivity in Rice 被引量:44
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作者 Bo-Ran Shen Li-Min Wang +9 位作者 Xiu-Ling Lin Zhen Yao Hua-Wei Xu Cheng-Hua Zhu Hai-Yan teng Li-Li Cui E.-E. Liu Jian-Jun Zhang Zheng-hui He Xin-Xiang Peng 《Molecular Plant》 SCIE CAS CSCD 2019年第2期199-214,共16页
Over the past few years, three photorespiratory bypasses have been introduced into plants, two of which led to observable in creases in photos yn thesis and biomass yield. However, most of the experiments were carried... Over the past few years, three photorespiratory bypasses have been introduced into plants, two of which led to observable in creases in photos yn thesis and biomass yield. However, most of the experiments were carried out using Arabidopsis under controlled environmental conditions, and the increases were only observed under low-light and short-day conditions. In this study, we designed a new photorespiratory bypass (called GOC bypass), characterized by no reducing equivalents being produced during a complete oxidation of glycolate into CO2 catalyzed by three rice-self-originating enzymes, i.e., glycolate oxidase, oxalate oxidase, and catalase. We successfully established this bypass in rice chloroplasts using a multi-gene assembly and transformation system. Transgenic rice plants carrying GOC bypass (GOC plants) showed significant increases in photosynthesis efficiency, biomass yield, and nitrogen content, as well as several other CO2-enriched phe no types under both greenhouse and field conditions .Grain yield of GOC plants varied depending on seeding season and was increased significantly in the spring. We further demonstrated that GOC plants had significant advantages under high-light conditions and that the improvements in GOC plants resulted primarily from a photosynthetic CO2-concentrating effect rather than from improved energy balance. Taken together, our results reveal that engineering a newly designed chloroplastic photorespiratory bypass could increase photosynthetic efficiency and yield of rice plants grown in field conditions, particularly under high light. 展开更多
关键词 photorespiratory BYPASS PHOTOSYNTHETIC EFFICIENCY PRODUCTIVITY RICE
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Multi-energy Storage System Model Based on Electricity Heat and Hydrogen Coordinated Optimization for Power Grid Flexibility 被引量:44
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作者 Yun teng Zedi Wang +3 位作者 Yan Li Qian Ma Qian hui Shubin Li 《CSEE Journal of Power and Energy Systems》 SCIE CSCD 2019年第2期266-274,共9页
Based on decreasing the flexibility of the power grid through the integration of large-scale renewable energy,a multi-energy storage system architectural model and its coor-dination operational strategy with the same ... Based on decreasing the flexibility of the power grid through the integration of large-scale renewable energy,a multi-energy storage system architectural model and its coor-dination operational strategy with the same flexibility as in the pumped storage power station and battery energy storage system(BESS)are studied.According to the new energy fluctuation characteristics and the different peak valley parameters in the power grid,this paper proposes a electricity heat hydrogen multi-energy storage system(EHH-MESS)and its coordination and optimization operational model to reduce the curtailment of wind power and photovoltaic(PV)to the power grid and improve the flexibility of the power grid.Finally,this paper studied the simulation model of an energy storage optimization control strategy after the multi-energy storage system is connected to the distribution networks,and analyzed three operational modes of the multi-energy storage system.The simulation results show that the EHH-MESS proposed in this paper has a better power grid regulation flexibility and economy,and can be used to replace the battery energy storage system based on MATLAB. 展开更多
关键词 Electricity heat and hydrogen conversion flexibility of power grid multi-energy storage new energy curtailment
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“无废”电–氢充能服务区多源微网优化运行模型 被引量:39
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作者 滕云 闫佳佳 +1 位作者 回茜 陈哲 《中国电机工程学报》 EI CSCD 北大核心 2021年第6期2074-2087,共14页
针对具有电、氢充能需求的高速公路服务区内的多能源负荷需求及服务区与周边生活垃圾处理需求,提出一种全可再生能源供能的"无废"电-氢充能服务区多源微网模型。首先,在电制氢、燃料电池、热解炉等多能源转换与存储设备的能... 针对具有电、氢充能需求的高速公路服务区内的多能源负荷需求及服务区与周边生活垃圾处理需求,提出一种全可再生能源供能的"无废"电-氢充能服务区多源微网模型。首先,在电制氢、燃料电池、热解炉等多能源转换与存储设备的能量输入输出特性模型基础上,建立无废充能服务区多源微网(zero-waste charging service area multi-energy microgrid,ZWSA-MEMG)模型;其次,研究ZWSA-MEMG中多种能源转换、存储特性及多能流协调关系,建立基于高速公路充能服务区多源微网功率平衡、充能时间、多源负荷供能可靠性、可提供的电网调节性能等约束下的运行成本优化模型及其求解方法。最后,以我国西北某高速服务区实际多能源运行数据为基础,建立"无废"电-氢充能服务区多源微网优化运行仿真模型,算例仿真结果表明,该文提出的ZWSA-MEMG优化运行模型可有效提升具有垃圾处理能力的电-氢充能多能源系统的经济性,并可为电网提供较好的调节特性。 展开更多
关键词 充能服务区 氢能汽车 多能源微网 无废化 全可再生能源
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考虑区域多能源系统集群协同优化的联合需求侧响应模型 被引量:38
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作者 滕云 刘硕 +1 位作者 回茜 陈哲 《中国电机工程学报》 EI CSCD 北大核心 2020年第22期7282-7295,共14页
风电、光伏发电等波动电源接入比例不断提高,使得区域多能源系统中能量转化和协调能力减弱。基于此,该文提出一种多个区域级多能源系统互联后多目标协同优化的联合需求侧响应模型及响应策略求解算法。首先提出联合需求侧响应概念及模型... 风电、光伏发电等波动电源接入比例不断提高,使得区域多能源系统中能量转化和协调能力减弱。基于此,该文提出一种多个区域级多能源系统互联后多目标协同优化的联合需求侧响应模型及响应策略求解算法。首先提出联合需求侧响应概念及模型,并在此基础上研究多区域电气热(冷)互联系统中的多种能源形式间的能量转化模型;以多个区域多能源系统运行总成本最小、碳排放最小为目标,建立多区域电气热(冷)互联系统多目标优化模型;然后,研究多区域电气热(冷)互联系统多目标运行优化调度策略,建立基于NSGA-Ⅱ算法的多区域能源互联系统协同优化算法。最后,基于东北3个地区电热气多能源系统,建立联合需求侧响应及其优化运行仿真模型。仿真结果表明,提出的联合需求侧响应模及其优化运行策略,能够有效提高多个区域能源系统间的能量协调能力,增强多能源互联系统总体需求侧响应能力,并降低需求侧响应成本。 展开更多
关键词 联合需求侧响应 多区域能源互联系统 互联系统集群 多目标协调优化 NSGA-Ⅱ算法
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Clinical application of three-dimensional printing in the personalized treatment of complex spinal disorders 被引量:34
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作者 Yi-Tian Wang xin-Jian Yang +3 位作者 Bin yan teng-hui Zeng Yi-Yan Qiu si-Jin Chen 《Chinese Journal of Traumatology》 CAS CSCD 2016年第1期31-34,共4页
Purpose: To investigate the usefulness of three-dimensional (3D) printing in complex spinal surgery. Methods: The study was conducted from October 2014 to March 2015 in Shenzhen Second Peoples' Hospital and 4 cas... Purpose: To investigate the usefulness of three-dimensional (3D) printing in complex spinal surgery. Methods: The study was conducted from October 2014 to March 2015 in Shenzhen Second Peoples' Hospital and 4 cases of complex severe spinal disorders were selected from our department. Among them one patient combined with congenital scoliosis, one with atlas neoplasm, one with atlantoaxial dislocation, and the rest one with atlantoaxial fracture-dislocation. The data of the diseased region was collected from computerized tomography scans for 3D digital reconstruction and rapid prototyping to prepare photosensitive resin models, which were applied in the treatment of these cases. Results: The use of 3D models reduced operating time and intraoperative blood loss as well as the risk of postoperative complications. Furthermore, no pedicle penetrations or screw misplacement occurred according to the postoperative planar radiographic images. Conclusion: The tactile models from 3D printing allow direct observation and measurement, helping the orthopedists to have accurate morphometric information to provide personalized surgical planning and better communication with the patient and coworkers. Moreover, the photosensitive resin models can also guide the actual surgery with the drilling of pedicle screws and safe resection of tumor. 展开更多
关键词 Complex spinal disordersThree-dimensional printingPersonalized treatment
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Main controlling factors and enrichment area evaluation of shale gas of the Lower Paleozoic marine strata in south China 被引量:32
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作者 Xian-Ming Xiao Qiang Wei +5 位作者 Hai-Feng Gai teng-Fei Li Mao-Lin Wang Lei Pan Ji Chen hui Tian 《Petroleum Science》 SCIE CAS CSCD 2015年第4期573-586,共14页
The Lower Paleozoic shale in south China has a very high maturity and experienced strong tectonic defor- mation. This character is quite different from the North America shale and has inhibited the shale gas evaluatio... The Lower Paleozoic shale in south China has a very high maturity and experienced strong tectonic defor- mation. This character is quite different from the North America shale and has inhibited the shale gas evaluation and exploration in this area. The present paper reports a com- prehensive investigation of maturity, reservoir properties, fluid pressure, gas content, preservation conditions, and other relevant aspects of the Lower Paleozoic shale from the Sichuan Basin and its surrounding areas. It is found that within the main maturity range (2.5 % 〈 EqRo 〈 3.5 %) of the shale, its porosity develops well, having a positive cor- relation with the TOC content, and its gas content is con- trolled mainly by the preservation conditions related to the tectonic deformation, but shale with a super high maturity (EqRo 〉 3.5 %) is considered a high risk for shale gas exploration. Taking the southern area of the Sichuan Basin and the southeastern area of Chongqing as examples of uplifted/folded and faulted/folded areas, respectively, geo- logical models of shale gas content and loss were proposed. For the uplifted/folded area with a simple tectonic defor- mation, the shale system (with a depth 〉 2000 m) has lar- gely retained overpressure during uplifting without a great loss of gas, and an industrial shale gas potential is generally possible. However, for the faulted/folded area with a strong tectonic deformation, the sealing condition of the shale system was usually destroyed to a certain degree with a great loss of free gas, which decreased the pressure coefficient and resulted in a low production capacity. It is predicted that the deeply buried shale (〉3000 m) has a greater gas potential and will become the focus for further exploration and development in most of the south China region (outside the Sichuan Basin). 展开更多
关键词 Lower Paleozoic shale gas MATURITY Maincontrolling factors Tectonic deformation
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混合同步网络课堂有效性的实证研究 被引量:30
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作者 杨俊锋 崔丽霞 +2 位作者 吴滕 潘慧 洪河条 《电化教育研究》 CSSCI 北大核心 2018年第12期50-56,77,共8页
互联网时代,课堂的形式包括物理课堂、同步网络课堂和异步网络课堂。混合同步网络课堂(BSCC)通常使用具有教学功能的视频会议系统连接不同地区的两个班级,实现网络课堂和物理课堂的混合,可以用来连接城市和农村的班级。BSCC的规模化应... 互联网时代,课堂的形式包括物理课堂、同步网络课堂和异步网络课堂。混合同步网络课堂(BSCC)通常使用具有教学功能的视频会议系统连接不同地区的两个班级,实现网络课堂和物理课堂的混合,可以用来连接城市和农村的班级。BSCC的规模化应用可以促进教育均衡和公平,研究其有效性及影响因素具有重要的现实意义。本研究以宁波市两所小学作为实验学校,开展了两个学年的混合同步网络教学,通过前后测成绩的比较分析、问卷调查、课堂观察等方法探讨了BSCC的有效性。研究发现:(1)混合同步网络课堂开展后,薄弱学校学生的成绩有了较大幅度的提升;(2)近远两端的学生对混合同步网络课堂的效率、交互、环境、教师支持、任务取向和课件设计等几个方面的感知差异不大;(3)教师对近远两端课堂学生的关注基本相同,并没有顾此失彼,这是BSCC有效性的重要保障。 展开更多
关键词 混合同步网络课堂 有效性 实证研究
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考虑热惯性不确定性的多能源系统两阶段鲁棒优化调度模型 被引量:27
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作者 孙鹏 滕云 +1 位作者 回茜 陈哲 《中国电机工程学报》 EI CSCD 北大核心 2021年第21期7249-7260,共12页
该文提出考虑供热系统热惯性不确定性的多能源系统协调优化方法。首先,基于多能源系统能量输运网络,分析热网热能传递延迟模型和等效储能模型;其次,研究热网管线输运能力描述参数,建立供热管道传输准动态方程。分析热网运行状态监测数... 该文提出考虑供热系统热惯性不确定性的多能源系统协调优化方法。首先,基于多能源系统能量输运网络,分析热网热能传递延迟模型和等效储能模型;其次,研究热网管线输运能力描述参数,建立供热管道传输准动态方程。分析热网运行状态监测数据与热能流模型间差异的量化方法,建立热惯性不确定性模型。然后,以电-热-气多能源系统运行成本最低为目标函数,构建考虑热惯性不确定性的多能源系统两阶段鲁棒优化调度模型,并引入列约束生成算法、强对偶理论对于模型进行求解。最后,以东北某地多能源系统实际运行数据为基础建立仿真模型,算例结果表明基于热惯性不确定性的多能源系统鲁棒优化调度模型能够较好地兼顾系统调度成本和可靠性。 展开更多
关键词 多能源系统 热惯性 储能 不确定性 鲁棒优化
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考虑垃圾处理与调峰需求的可持续化城市多能源系统规划 被引量:25
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作者 王泽镝 滕云 +1 位作者 回茜 陈哲 《中国电机工程学报》 EI CSCD 北大核心 2021年第11期3781-3796,共16页
随着"垃圾围城"的日益加剧及城市能源体系中多种能源形式间相互融合的不断深入,垃圾处理设施供能与多能源系统间的相互影响和作用越来越成为城市能源系统规划所需考虑的重点问题之一。针对计及能源化利用型废物处理设施的城... 随着"垃圾围城"的日益加剧及城市能源体系中多种能源形式间相互融合的不断深入,垃圾处理设施供能与多能源系统间的相互影响和作用越来越成为城市能源系统规划所需考虑的重点问题之一。针对计及能源化利用型废物处理设施的城市多能源系统规划问题,该文研究废物处理设施的能源供需特性及其调峰潜力,提出垃圾焚烧电厂和污水制气设施参与电网气网调峰策略,构建可持续性多能源系统规划模型。最后参考东北某市的实际能源与垃圾堆存量数据,建立可持续化城市多能源系统规划仿真模型,仿真结果及分析表明,该文提出的多能源系统规划模型可有效降低城市多能源系统规划成本,实现垃圾处理能力、垃圾供能与调峰需求间的高效协调。 展开更多
关键词 垃圾处理 负荷调峰 多能源耦合 系统规划 可持续性
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塔里木盆地克拉苏构造带超深复杂气田井全生命周期地质工程一体化实践 被引量:24
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作者 田军 刘洪涛 +3 位作者 滕学清 蔡振忠 张辉 曹立虎 《中国石油勘探》 CAS CSCD 北大核心 2019年第2期165-173,共9页
克拉苏构造带天然气总资源量丰富,是塔里木盆地天然气增储上产的主力区块。受强烈造山运动的影响,克拉苏构造带地质工程条件极为复杂,呈现出"一深(垂深7000~8000m)、三高(高温130~190℃、高压116~136MPa、高地应力130~180MPa)、两... 克拉苏构造带天然气总资源量丰富,是塔里木盆地天然气增储上产的主力区块。受强烈造山运动的影响,克拉苏构造带地质工程条件极为复杂,呈现出"一深(垂深7000~8000m)、三高(高温130~190℃、高压116~136MPa、高地应力130~180MPa)、两低(孔隙度4%~8%、渗透率0.01~0.1mD)、两厚(巨厚砾石层5500m、巨厚盐膏层4500m)、一陡(地层倾角87°)"的特征,导致安全、效益勘探开发难度巨大。为了实现克拉苏构造带的优快钻井与改造上产,立足于实践地质工程一体化,建设多学科一体化研究团队,创新一体化工作模式,开展了超深复杂气田提速、提产、提质攻关研究。采用关键层段精准预测、个性化钻头设计、油基钻井液体系研发等手段相结合的方法,实现了全井段安全快速钻井;根据甜点预测、裂缝评价与分类,建立了基于天然裂缝可压裂性的改造提产优选策略;结合地层特点、流体性质、工况条件等因素进行系统屏障设计,确保了井筒质量。经过地质工程一体化实践的不断发展完善,超深井钻井周期从"十二五"期间的336天降至2017年的277天,单井平均增产4~5倍、井完整性完好率不断提升,为克拉苏超深复杂气田井安全效益开发提供了有力的技术保障。 展开更多
关键词 克拉苏构造带 超深复杂气田 地质工程一体化 组织模式 实践 提速 提产 提质
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A Model of Electro-thermal Hybrid Energy Storage System for Autonomous Control Capability Enhancement of Multi-energy Microgrid 被引量:22
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作者 Yun teng Peng Sun +2 位作者 Qian hui Yan Li Zhe Chen 《CSEE Journal of Power and Energy Systems》 SCIE CSCD 2019年第4期489-497,共9页
In view of the problem of low self-service capability of the microgrid due to the high operating cost and low capacity of the traditional battery energy storage system.In this paper,an electrothermal hybrid energy sto... In view of the problem of low self-service capability of the microgrid due to the high operating cost and low capacity of the traditional battery energy storage system.In this paper,an electrothermal hybrid energy storage model based on electricity,hydrogen and thermal energy conversion and storage is introduced,and a microgrid autonomous operational strategy is proposed.First,the addition of the power to hydrogen transfer equipment in the traditional combined heat and power(TCHP)system without battery energy storage is studied,and a micro gas turbine,electric to hydrogen transfer equipment and electric boiler based electrothermal energy storage system(ETSS)model is established.Aiming at the lowest comprehen-sive operating cost of multiple energy sources in a microgrid and maximizing the consumption of curtailed wind,the multi-objective scheduling model of an electrothermal hybrid energy storage system is established,then the multi-energy autonomous operational strategy of a microgrid is proposed.Lastly,the simulation of a multi-energy microgrid in Northeast China is taken as an example.The results of the simulation showed that compared with a combined heat and power microgrid system considering conventiona battery energy storage,a multi-energy microgrid system using electrothermal hybrid energy storage has better flexibility and economy,and can improve wind power accommodation. 展开更多
关键词 Autonomous operation energy storage multi-objective optimization multi-energy microgrid wind power
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红托竹荪多糖对大鼠酒精性肝损伤的保护作用 被引量:21
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作者 颜蜜 滕春丽 +3 位作者 陶会 杨鸿波 孙晓红 谭红 《菌物学报》 CAS CSCD 北大核心 2022年第2期291-302,共12页
研究红托竹荪多糖(Dictyophora rubrovalvata polysaccharide,DRP)对酒精所致大鼠肝损伤的保护作用。采用苯酚-硫酸法测得DRP的含量为74.68%±1.32%,利用傅里叶红外光谱初步分析表明DRP是含有α-糖苷键和β-糖苷键的吡喃环多糖。当... 研究红托竹荪多糖(Dictyophora rubrovalvata polysaccharide,DRP)对酒精所致大鼠肝损伤的保护作用。采用苯酚-硫酸法测得DRP的含量为74.68%±1.32%,利用傅里叶红外光谱初步分析表明DRP是含有α-糖苷键和β-糖苷键的吡喃环多糖。当DRP浓度达到3.0 mg/mL时,DPPH自由基的清除率达到80.12%,其还原力为0.31,对羟基自由基的清除率达到88.07%。雄性SD大鼠被随机分为6组:空白对照组(NC)、模型对照组(MC)、阳性对照组(PC)、红托竹荪多糖低(LDRP)、中(MDRP)、高(HDRP)剂量干预组,连续灌胃28 d后将其安乐死,测定血清中AST、ALT、TG水平以及肝脏SOD、GSH、MDA、TNF-α、IL-6水平,并根据病理切片分析红托竹荪多糖对大鼠酒精性肝损伤的保护程度。与MC组相比,DRP各剂量组血清AST、ALT、TG水平显著降低(P<0.05),肝脏SOD和GSH水平显著上升(P<0.05),MDA、TNF-α、IL-6含量显著下降(P<0.05),肝脏细胞变性和坏死等病理现象明显改善。DRP具有一定的体外抗氧化能力,并且能缓解酒精所致的大鼠肝脏损伤,其缓解作用与抗氧化能力增强、炎症因子表达水平降低有关。 展开更多
关键词 食用菌多糖 红托竹荪 酒精性肝损伤 抗氧化作用 炎症反应
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Genesis of green sandstone/mudstone from Middle Jurassic Zhiluo Formation in the Dongsheng Uranium Orefield, Ordos Basin and its enlightenment for uranium mineralization 被引量:21
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作者 Ruo-shi Jin Xiao-xi Feng +9 位作者 Xue-ming teng Feng-jun Nie Hai-yang Cao hui-qun Hou Hong-xu Liu Pei-sen Miao Hua-lei Zhao Lu-lu Chen Qiang Zhu Xiao-xi Zhou 《China Geology》 2020年第1期52-66,共15页
The middle Jurassic Zhiluo Formation in the Dongsheng is comprised of a big set of green sandstone/mudstone with most of uranium orebodies occurring in close proximity to its footwall.By synthesizing field observation... The middle Jurassic Zhiluo Formation in the Dongsheng is comprised of a big set of green sandstone/mudstone with most of uranium orebodies occurring in close proximity to its footwall.By synthesizing field observations,region analysis,data collected from previous coal and uranium borehole,a regional north-south geological profile across the entire orefield is conducted.Experiments on sandstone/mudstone including rock mineral identification,clastic micromorphology and element geochemistry were carried out.Information from the geological profile indicates that green sandstone/mudstone is widely present in a stable horizon with clear boundaries to the country rock.Microscopic observations and geochemical data on sandstone/mudstone exhibit similar mineral composition with almost identical slightly flat,minor Eu enriched,Ce depleted chondrite-normalized REE patterns.Furthermore,the green clay membrane of the clasts has a complex composition containing chlorite/smectite,green smectite,chlorite,and green kaolinite,with elements including Fe,Mg,Si,and Al.These above results indicate that the green sandstone/mudstone underwent resemble sedimentary diagenetic processes as the country rock without transformation by large-scale regional fluid,while the existence of Fe2+-rich membrane is the main factor to the green sandstone/mudstone.Further concentration of the pre-enrichment uranium during diagenetic process led to the final formation for uranium deposits.The above studies are conducive to enrich the metallogenic mechanism of sandstone type uranium deposits and could provide certain reference for uranium exploration and deployment. 展开更多
关键词 Sandstone-type uranium deposit Green sandstone/mudstone DIAGENESIS Zhiluo Formation Minerral exploration engineering Ordos Basin Inner Mongolia China
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心肺运动试验定量评估PCI前后心肺功能的临床研究 被引量:20
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作者 邓维 孙兴国 +9 位作者 郭志勇 葛万刚 李浩 张也 董文涛 腾志涛 孙杏芸 于辉 费家玥 谢友红 《重庆医科大学学报》 CAS CSCD 北大核心 2019年第5期668-673,共6页
目的:探讨症状限制的极限心肺运动试验(cardiopulmonary exercise testing,CPET)在定量评估经皮冠状动脉腔内血管成形术(percutaneous coronary intervention,PCI)前后心肺功能中的临床应用价值。方法:利用 CPET 对 12 例正常人及 12 ... 目的:探讨症状限制的极限心肺运动试验(cardiopulmonary exercise testing,CPET)在定量评估经皮冠状动脉腔内血管成形术(percutaneous coronary intervention,PCI)前后心肺功能中的临床应用价值。方法:利用 CPET 对 12 例正常人及 12 例冠脉造影术确诊冠心病拟行 PCI 的患者手术前后心肺功能分别定量评估,利用标准化分析对 CPET 指标进行解读;并在同期测定左室射血分数(left ventricular ejection fraction,LVEF),比较手术前后 CPET 指标的变化及与 LVEF 的相关性。结果:LVEF 术前[(42.83±5.92)%]与术后[(45.08±4.76)%]比较,具有统计学差异(P<0.05);CPET 核心指标峰值摄氧量、无氧阈值、峰值氧脉搏、摄氧效率平台、二氧化碳通气当量斜率、二氧化碳通气当量最低值、峰值负荷功率、递增功率运动时间正常对照组分别为(1.99±0.19) L/min、(1.22±0.19) L/min、(14.18±2.59) mL/次、(47.10±4.44)、(23.01±2.63)、(25.06±2.43)、(162±17.6) W、(6.47±0.80) min,术前组上述指标分别为(1.41±0.46) L/min、(0.87±0.23) L/min、(11.43±3.29) mL/次、(40.13±5.18)、(27.85±4.81)、(29.55±3.90)、(112.00±51.10) W、(5.28±1.81) min,术前组均低于正常对照组(P<0.05);术后组各指标分别为(1.59±0.33) L/min、(1.02±0.20) L/min、(12.37±2.72) mL/次、(39.20±5.60)、(26.93±2.88)、(29.30±2.82)、(132.00±31.70) W、(6.21±1.05) min,与术前比较,峰值摄氧量、无氧阈值、峰值氧脉搏、峰值负荷功率、递增功率运动时间均提高,具有统计学差异(P<0.05);摄氧效率平台、二氧化碳通气当量斜率、二氧化碳通气当量最低值与术前比较无统计学差异(P>0.05);CPET 核心指标与 LVEF 呈高度相关(r 值绝对值为 0.579~0.908,均 P<0.05)。结论:CPET 的核心指标可用于无创定量监测 PCI 术前后心肺功能的变化情况,具有良好的临床应用价值。 展开更多
关键词 心肺运动试验 经皮冠状动脉腔内血管成形术 左室射血分数 定量评估
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紫河车联合寿胎丸加味治疗冷冻胚胎移植术后雌激素低下先兆流产患者临床研究 被引量:19
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作者 刘昱磊 刘新玉 +4 位作者 贝剑宏 宁艳 滕辉 王俊玲 余佩琳 《天津中医药》 CAS 2018年第3期175-178,共4页
[目的]以冷冻胚胎移植(FET)术后雌二醇(E2)低的先兆流产患者为对象,采用紫河车联合寿胎丸加味治疗,观察临床疗效。[方法]选择FET术后14 d,100<E2<200 pg/m L的先兆流产患者160例,随机分配至治疗组和对照组。观察治疗前后中医症状... [目的]以冷冻胚胎移植(FET)术后雌二醇(E2)低的先兆流产患者为对象,采用紫河车联合寿胎丸加味治疗,观察临床疗效。[方法]选择FET术后14 d,100<E2<200 pg/m L的先兆流产患者160例,随机分配至治疗组和对照组。观察治疗前后中医症状评分,E_2、血清绒毛膜促性腺激素(β-HCG)上升情况及妊娠成功率。[结果]两组患者治疗后中医临床症状积分较治疗前显著下降(P<0.01);血清E2、β-HCG水平均显著高于本组治疗前水平(P<0.01)。与对照组相比,治疗组治疗后所有症状积分显著下降(P<0.05);E2、β-HCG水平显著升高(P<0.05)。治疗组和对照组妊娠成功率分别为77.5%、62.5%,差异有统计学意义(P<0.05)。[结论]紫河车联合寿胎丸加味中药可有效改善FET术后雌激素低下先兆流产中医临床症状,显著提升雌激素及β-HCG水平,提高妊娠成功率,值得临床中推广使用。 展开更多
关键词 雌激素 先兆流产 冷冻胚胎移植 临床研究
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不同引发方法对青绿苔草种子发芽的影响 被引量:16
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作者 李慧 滕珂 +6 位作者 岳跃森 滕文军 温海峰 韩朝 张辉 范希峰 武菊英 《草业科学》 CAS CSCD 北大核心 2021年第8期1537-1547,共11页
青绿苔草(Carex leucochlora)作为一种优良的草坪地被植物,在园林绿化建设中具有广泛的应用前景,但由于其种子发芽时间长,限制了其大规模开发利用。本文研究了不同引发剂和引发方法对青绿苔草种子发芽的影响。结果表明:单一引发中,5%KNO... 青绿苔草(Carex leucochlora)作为一种优良的草坪地被植物,在园林绿化建设中具有广泛的应用前景,但由于其种子发芽时间长,限制了其大规模开发利用。本文研究了不同引发剂和引发方法对青绿苔草种子发芽的影响。结果表明:单一引发中,5%KNO3以及480 mg·L^(-1)赤霉素(GA3)对青绿苔草种子的引发效果较佳,经处理后,与未经任何处理的青绿苔草种子(CK)相比,其发芽势分别提高11%和32%,发芽率均提高4%,发芽指数分别提高2.06和2.69,平均发芽时间分别缩短2.11和2.72 d;混合处理中,效果最佳的处理为先将种子用5%KNO3引发,后经10%NaOH溶液浸种20 min,再通过480 mg·L^(-1) GA3进行引发,与CK相比,其发芽势和发芽率分别提高92%和5%,发芽指数提高5.92,平均发芽时间由9.01 d缩短至4.46 d。本研究解决了青绿苔草种子发芽慢的问题,为青绿苔草在园林绿地中规模化应用提供了依据。 展开更多
关键词 青绿苔草 种子 渗调引发 激素引发 水引发 混合处理 萌发特性
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Deep learning applied to two-dimensional color Doppler flow imaging ultrasound images significantly improves diagnostic performance in the classification of breast masses:a multicenter study 被引量:18
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作者 teng-Fei Yu Wen He +19 位作者 Cong-Gui Gan Ming-Chang Zhao Qiang Zhu Wei Zhang hui Wang Yu-Kun Luo Fang Nie Li-Jun Yuan Yong Wang Yan-Li Guo Jian-Jun Yuan Li-Tao Ruan Yi-Cheng Wang Rui-Fang Zhang Hong-Xia Zhang Bin Ning Hai-Man Song Shuai Zheng Yi Li Yang Guang 《Chinese Medical Journal》 SCIE CAS CSCD 2021年第4期415-424,共10页
Background:The current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions.In China,breast masses are divided into four categories according to the treatment m... Background:The current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions.In China,breast masses are divided into four categories according to the treatment method:inflammatory masses,adenosis,benign tumors,and malignant tumors.These categorizations are important for guiding clinical treatment.In this study,we aimed to develop a convolutional neural network(CNN)for classification of these four breast mass types using ultrasound(US)images.Methods:Taking breast biopsy or pathological examinations as the reference standard,CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers.The patients were randomly divided into training and test groups(n=1810 vs.n=1813).Separate models were created for two-dimensional(2D)images only,2D and color Doppler flow imaging(2D-CDFI),and 2D-CDFI and pulsed wave Doppler(2D-CDFI-PW)images.The performance of these three models was compared using sensitivity,specificity,area under receiver operating characteristic curve(AUC),positive(PPV)and negative predictive values(NPV),positive(LR+)and negative likelihood ratios(LR-),and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators,between images from different hospitals with AUC,and with the performance of 37 radiologists.Results:The accuracies of the 2D,2D-CDFI,and 2D-CDFI-PW models on the test set were 87.9%,89.2%,and 88.7%,respectively.The AUCs for classification of benign tumors,malignant tumors,inflammatory masses,and adenosis were 0.90,0.91,0.90,and 0.89,respectively(95%confidence intervals[CIs],0.87-0.91,0.89-0.92,0.87-0.91,and 0.86-0.90).The 2D-CDFI model showed better accuracy(89.2%)on the test set than the 2D(87.9%)and 2D-CDFI-PW(88.7%)models.The 2D model showed accuracy of 81.7%on breast masses≤1 cm and 82.3%on breast masses>1 cm;there was a significant difference between the two groups(P<0.001).The accuracy of the CNN classifications for the test s 展开更多
关键词 Deep learning ULTRASONOGRAPHY Breast diseases DIAGNOSIS
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鳗鱼骨胶原肽钙螯合物的制备及其稳定性和Caco-2吸收特性 被引量:16
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作者 钱跃威 徐瀚麟 +3 位作者 吕奇晏 陈智超 滕慧 陈雷 《食品科学》 EI CAS CSCD 北大核心 2020年第24期1-8,共8页
结合胃蛋白酶、胰蛋白酶和胰凝乳蛋白酶制备具有高钙结合能力的鳗鱼胶原蛋白肽(eel bone collagen peptide,EBCP)。通过优化确定制备EBCP-Ca的最佳条件为40℃、pH 7.5、40 min、多肽与钙质量比5∶1,此条件下钙螯合率达80%以上。荧光光... 结合胃蛋白酶、胰蛋白酶和胰凝乳蛋白酶制备具有高钙结合能力的鳗鱼胶原蛋白肽(eel bone collagen peptide,EBCP)。通过优化确定制备EBCP-Ca的最佳条件为40℃、pH 7.5、40 min、多肽与钙质量比5∶1,此条件下钙螯合率达80%以上。荧光光谱、傅里叶变换红外光谱和扫描电子显微镜检测结果表明,胶原蛋白肽的羧基和氨基氮原子可能会螯合钙,从而形成EBCP-Ca。EBCP-Ca可在不同温度、pH值条件下保持稳定性并进行模拟胃肠道消化,同时EBCP-Ca对Caco-2细胞呈现低毒性作用。另外,使用Caco-2细胞单层模型验证EBCP-Ca在体外的钙摄取率,研究EBCP-Ca浓度和培养时间对Caco-2细胞钙离子质量浓度和碱性磷酸酶(alkaline phosphatase,AKP)活性的影响。结果表明,EBCP-Ca能提高AKP活性,进而有利于促进人体胃肠道中钙的吸收。该研究为开发新的钙补充剂和鳗鱼骨的高价值利用提供了一定科学依据。 展开更多
关键词 鳗鱼骨 骨钙结合肽 稳定性 细胞吸收
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