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Changes in neurological and pathological outcomes in a modified rat spinal cord injury model with closed canal 预览
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作者 Xin Sun Xing-Zhen Liu +4 位作者 Jia Wang Hai-Rong Tao Tong Zhu Wen-Jie Jin Kang-Ping Shen 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期697-704,共8页
Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively c... Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively complete spinal canal.Thus,open spinal cord injury models often do not simulate real injuries,and few previous studies have investigated whether having a closed spinal canal after a primary spinal cord injury may influence secondary processes.Therefore,we aimed to assess the differences in neurological dysfunction and pathological changes between rat spinal cord injury models with closed and open spinal canals.Sprague-Dawley rats were randomly divided into three groups.In the sham group,the tunnel was expanded only,without inserting a screw into the spinal canal.In the spinal cord injury with open canal group,a screw was inserted into the spinal canal to cause spinal cord injury for 5 minutes,and then the screw was pulled out,leaving a hole in the vertebral plate.In the spinal cord injury with closed canal group,after inserting a screw into the spinal canal for 5 minutes,the screw was pulled out by approximately 1.5 mm and the flat end of the screw remained in the hole in the vertebral plate so that the spinal canal remained closed;this group was the modified model,which used a screw both to compress the spinal cord and to seal the spinal canal.At 7 days post-operation,the Basso-Beattie-Bresnahan scale was used to measure changes in neurological outcomes.Hematoxylin-eosin staining was used to assess histopathology.To evaluate the degree of local secondary hypoxia,immunohistochemical staining and western blot assays were applied to detect the expression of hypoxia-inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF).Compared with the spinal cord injury with open canal group,in the closed canal group the Basso-Beattie-Bresnahan scores were lower,cell morphology was more irregular,the percentage of morphologically normal neurons was lower,the percentages of HIF-1α-and VEGF-immunorea 展开更多
关键词 Basso-Beattie-Bresnahan scores CLOSED SPINAL CANAL HIF-1α hypoxia MODEL nerve regeneration open SPINAL CANAL rat secondary INJURY SPINAL cord INJURY VEGF
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CLS-Miner: efficient and effective closed high-utility itemset mining
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作者 Thu-Lan DAM Kenli LI +1 位作者 Philippe FOURNIER-VIGER Quang-Huy DUONG 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第2期357-381,共25页
High-utility itemset mining (HUIM) is a popular data mining task with applications in numerous domains. However, traditional HUIM algorithms often produce a very large set of high-utility itemsets (HUIs). As a result,... High-utility itemset mining (HUIM) is a popular data mining task with applications in numerous domains. However, traditional HUIM algorithms often produce a very large set of high-utility itemsets (HUIs). As a result, analyzing HUIs can be very time consuming for users. Moreover, a large set of HUIs also makes HUIM algorithms less efficient in terms of execution time and memory consumption. To address this problem, closed high-utility itemsets (CHUIs), concise and lossless representations of all HUIs, were proposed recently. Although mining CHUIs is useful and desirable, it remains a computationally expensive task. This is because current algorithms often generate a huge number of candidate itemsets and are unable to prune the search space effectively. In this paper, we address these issues by proposing a novel algorithm called CLS-Miner. The proposed algorithm utilizes the utility-list structure to directly compute the utilities of itemsets without producing candidates. It also introduces three novel strategies to reduce the search space, namely chain-estimated utility co-occurrence pruning, lower branch pruning, and pruning by coverage. Moreover, an effective method for checking whether an itemset is a subset of another itemset is introduced to further reduce the time required for discovering CHUIs. To evaluate the performance of the proposed algorithm and its novel strategies, extensive experiments have been conducted on six benchmark datasets having various characteristics. Results show that the proposed strategies are highly efficient and effective, that the proposed CLS-Miner algorithm outperforms the current state-ofthe- art CHUD and CHUI-Miner algorithms, and that CLSMiner scales linearly. 展开更多
关键词 UTILITY MINING high-utility ITEMSET MINING CLOSED ITEMSET MINING CLOSED high-utility ITEMSET MINING
鼻内镜下早期手术治疗鼻骨骨折伴鼻中隔骨折31例 预览
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作者 杨勇 程学仕 黄学勤 《安徽医药》 CAS 2019年第8期1632-1634,共3页
目的探讨早期行鼻内镜下手术治疗鼻骨骨折伴鼻中隔骨折的疗效和实用性。方法选取2014年1月至2017年12月合肥市第三人民医院收治的31例外伤性鼻骨骨折伴鼻中隔骨折的病人作为治疗组,行早期鼻内镜下鼻中隔成形术+骨折闭合性复位术;选取同... 目的探讨早期行鼻内镜下手术治疗鼻骨骨折伴鼻中隔骨折的疗效和实用性。方法选取2014年1月至2017年12月合肥市第三人民医院收治的31例外伤性鼻骨骨折伴鼻中隔骨折的病人作为治疗组,行早期鼻内镜下鼻中隔成形术+骨折闭合性复位术;选取同期该院31例不愿意行鼻内镜手术的外伤性鼻骨骨折伴鼻中隔骨折病人作为对照组,行骨折闭合性复位术。对病人术前及术后鼻腔通气及鼻腔外观进行视觉模拟评分(VAS),并观察两组病人术后鼻中隔穿孔、血肿、鼻腔粘连等并发症的发生情况。结果治疗组术后鼻腔外观(2.35±0.66)分及鼻腔通气(2.26±0.51)分VAS评分均优于对照组(3.06±1.24)分、(3.19±1.90)分,均差异有统计学意义(t=2.819、2.640,P=0.007、0.011)。治疗组与对照组比较,手术方法不增加手术风险。结论鼻骨骨折伴鼻中隔骨折的病人采取鼻内镜下鼻中隔成形术+骨折闭合性复位术治疗效果优于单纯骨折复位术,可同时解决鼻中隔骨折和鼻骨复位,减少手术危险性,避免了鼻中隔的二次手术,具有可行性、实用性、经济性。 展开更多
关键词 鼻骨 鼻中隔 骨折 闭合性 自然腔道内镜手术 鼻中隔成形术 闭合性复位术
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Epidemiological Pattern of Closed Femoral Shaft Fractures in a Regional Tertiary Hospital in Enugu, Nigeria 预览
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作者 E. C. Iyidobi R. T. Ekwunife +3 位作者 U. M. Enweani C. U. Nwadinigwe I. C. Okwesili H. C. Ekwedigwe 《生物科学与医学(英文)》 2019年第5期180-188,共9页
Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point o... Background: The femur is the longest and strongest tubular bone in the human body. The femoral shaft is the portion of the bone between 5 cm distal to the lesser trochanter and 6 cm proximal to the most distal point of the medial femoral condyle. Femoral shaft fractures often result from high energy forces. These fractures occur mostly among young adults. Objective: This was to determine the epidemiological pattern of closed femoral shaft fractures in a regional tertiary hospital in Enugu, Nigeria. Method: The study was a prospective study over a 12 month period (June 2015-May 2016) at National Orthopaedic Hospital, Enugu. Following ethical approval and written informed consent, patients were consecutively recruited. The patients were clinically and radiographically evaluated at presentation. The diagnosis of closed femoral shaft fractures were made from the physical examination finding of absent open wound communicating with the fracture hematoma in the thigh and anteroposterior (AP) and lateral x-rays of the affected thigh confirming the fracture pattern. The data collected included patients’ demographics, the cause of injury, the side of injury and anatomic site of the injury among other parameters. The data were collected using well designed and structured proforma. Results: A total of 52 femoral shaft fractures in 50 patients were included and analyzed using SPSS version 20.0. The age range of the patients is 18 - 85 years with a median age of 39.1 ± 14.9 years. The most commonly affected age group is 21 - 30 years. There was male preponderance with a male to female ratio of 2.3:1. Majority of the fractures (76.9%) resulted from road traffic crashes most commonly following motor vehicular accident (36.5%). Majority of the fractures (92.3%) are unilateral with right side to left side ratio of 1.2:1. Majority of the patients (51.9%) had Winquist Hansen grade III type of fracture. The most common associated injury is fractures of tibia/fibula followed by fracture of the neck of the ipsilateral femur. All the 展开更多
关键词 Epidemiology CLOSED FEMORAL SHAFT Fracture
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一种处理化工废水用封闭式中心传动浓缩机 预览
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作者 陈庆来 王春乔 《矿产综合利用》 CAS 北大核心 2019年第3期131-132,共2页
针对传统中心传动浓缩机在化工废水处理中的实际应用缺陷,设计了一种封闭式中心传动浓缩机,该封闭式中心传动浓缩机能够实现废水的回用和废气的回收,以满足化工行业废水处理固液分离的需要,并为同类工业废水用浓缩机的技术革新和技术改... 针对传统中心传动浓缩机在化工废水处理中的实际应用缺陷,设计了一种封闭式中心传动浓缩机,该封闭式中心传动浓缩机能够实现废水的回用和废气的回收,以满足化工行业废水处理固液分离的需要,并为同类工业废水用浓缩机的技术革新和技术改造提供借鉴。 展开更多
关键词 浓缩机 封闭式 高温易燃 环形密封 化工废水
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循环风量对串联辅助冷凝器的闭式热泵烘干系统的影响 预览 被引量:1
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作者 王浩 武卫东 +1 位作者 吕婉豆 胡锟 《制冷技术》 2019年第1期55-60,共6页
本文设计了一种带有串联式辅助冷凝器的闭式热泵烘干系统,并搭建了性能测试实验台,研究了冷凝器出风温度、系统能效比(COP)、单位时间除湿量和单位能耗除湿量等性能参数随循环风量的变化规律。结果表明:在一定范围内,随着循环风量的增大... 本文设计了一种带有串联式辅助冷凝器的闭式热泵烘干系统,并搭建了性能测试实验台,研究了冷凝器出风温度、系统能效比(COP)、单位时间除湿量和单位能耗除湿量等性能参数随循环风量的变化规律。结果表明:在一定范围内,随着循环风量的增大,冷凝器出风温度降低,系统能效比 COP升高,系统的单位时间除湿量先增大后减少,单位能耗除湿量减小;当循环风量为 683.1m^3/h时,系统获得最大单位时间除湿量,为3.59kg/h;当循环风量为642.6m^3/h,系统的单位能耗除湿量最大,为0.5170kg/(kWh)。研究结果可为闭式热泵烘干系统在工业方面的开发及应用提供一定参考。 展开更多
关键词 热泵 烘干系统 闭式 串联式辅助冷凝器 循环风量 系统性能
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Modelling and development of recycled water conditioning of copper-molybdenum ores processing 预览
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作者 Irina Pestriak Valery Morozov Erdenetuya Otchir 《矿业科学技术学报:英文版》 CSCD 2019年第2期313-317,共5页
Current use of enrichment and processing technologies of ores requires the introduction of closed circuits of water treatment.A decrease in technological properties is caused by accumulations of ion-molecular componen... Current use of enrichment and processing technologies of ores requires the introduction of closed circuits of water treatment.A decrease in technological properties is caused by accumulations of ion-molecular components in the circulating water.The objective of the simulation is to determine the maximum allowable concentrations of ions and molecules as well as the choice of conditions for deposition or adsorption.First of all,our examinations decrease the concentration of copper ions and fatty acids in the circulating water.By pre-mixing water with the highest concentration of these ions,a reduction of copper ion and fatty acid concentrations in the recycled water occurs.The results do not only ensure the achievement of the maximum permitted concentration(MPC)of copper and iron,significantly reducing the amount of oxidized copper,they also make it possible to use the united sewage as current water for the flotation process.Mixing and adding filtrate of tailings,discharges of urban wastewater treatment and effluent of ash pit of thermal power stations(TPS)to recycled water causes an increase in the capacity of the enrichment plant by 15-17%. 展开更多
关键词 TAILINGS RECYCLING WATER Closed cycle Urban waste WATER CONDITIONING FLOTATION of ORE Natural WATER
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急性闭合性软组织运动损伤的临床治疗研究进展 预览
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作者 陈晓琳 范蕊 +3 位作者 邹佐强 牟春明 李斌 吴宗辉 《医学信息》 2019年第3期34-36,41共4页
急性闭合性软组织运动损伤在体育运动中很常见,可能会引起关节、韧带、软组织撕裂等损伤。损伤发生后处理不恰当,会引起患者运动功能障碍,降低患者生活质量。现对闭合性软组织运动损伤的治疗方法进行综述,以期对闭合性软组织运动损伤的... 急性闭合性软组织运动损伤在体育运动中很常见,可能会引起关节、韧带、软组织撕裂等损伤。损伤发生后处理不恰当,会引起患者运动功能障碍,降低患者生活质量。现对闭合性软组织运动损伤的治疗方法进行综述,以期对闭合性软组织运动损伤的治疗有一个全面的认识,为临床闭合性软组织损伤的治疗提供一定的参考。 展开更多
关键词 损伤 闭合性 治疗 软组织
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On the Cegrell Classes Associated to a Positive Closed Current
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作者 Mohamed ZAWAY 《数学年刊:B辑英文版》 SCIE CSCD 2019年第4期567-584,共18页
The aim of this paper is to study the operatoron■ on some classes of plurisubharmonic (psh) functions, which are not necessary bounded, where T is a positive closed current of bidimension (q, q) on an open set ? of C... The aim of this paper is to study the operatoron■ on some classes of plurisubharmonic (psh) functions, which are not necessary bounded, where T is a positive closed current of bidimension (q, q) on an open set ? of C~n. The author introduces two classes F_p~T (?) and■ and shows first that they belong to the domain of definition of the operator■. Then the author proves that all functions that belong to these classes are C_T-quasi-continuous and that the comparison principle is valid for them. 展开更多
关键词 POSITIVE CLOSED CURRENT Plurisubharmonic function Capacity Monge-Ampère OPERATOR
快速康复外科理念在闭合性跟骨骨折患者护理中的临床应用 预览
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作者 邹丹 林家丽 +2 位作者 杨娜 谢青梅 张成娟 《岭南现代临床外科》 2019年第3期372-375,共4页
目的探究快速康复外科理念(ERAS)在闭合性跟骨骨折患者护理中的应用效果。方法选取本院2017年7月~2018年12月的全部闭合性跟骨骨折患者27名纳入ERAS系统的为ERAS组;2015年3月~2016年12月的全部30名闭合性跟骨骨折患者未进行ERAS管理的... 目的探究快速康复外科理念(ERAS)在闭合性跟骨骨折患者护理中的应用效果。方法选取本院2017年7月~2018年12月的全部闭合性跟骨骨折患者27名纳入ERAS系统的为ERAS组;2015年3月~2016年12月的全部30名闭合性跟骨骨折患者未进行ERAS管理的为传统组。其中传统组应用常规的围手术期护理,ERAS组应用ERAS快速外科理念对其进行干预护理。57例跟骨骨折患者均行手术治疗,其Sanders分型为Ⅱ型12例、Ⅲ型27例、Ⅳ型18例。对这57例闭合性跟骨骨折患者从术后疼痛评分、术后康复训练耐受时间、术后伤口肿胀消退时间、住院天数、住院费用、患者满意度等方面进行对比研究分析。结果ERAS组术后1d、3d、1w的疼痛评分均低于与传统组(P<0.05);术后康复训练时间上ERAS组优于传统组(P<0.05);术后肿胀消退时间ERAS组与传统组比较明显缩短(P<0.05),住院天数上ERAS组短于传统组(P<0.05),患者对护理满意度调查ERAS组评分高于传统组(P<0.01)。结论ERAS快速康复外科理念在治疗闭合性跟骨骨折患者中能够降低住院天数,提高患者对护理治疗的满意度。 展开更多
关键词 快速康复外科 闭合性 跟骨骨折 护理
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On Grauert–Riemenschneider Type Criteria
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作者 Zhi Wei WANG 《数学学报:英文版》 SCIE CSCD 2019年第5期609-618,共10页
Let (X,ω) be a compact Hermitian manifold of complex dimension n. In this article, we first survey recent progress towards Grauert-Riemenschneider type criteria. Secondly, we give a simplified proof of Boucksom's... Let (X,ω) be a compact Hermitian manifold of complex dimension n. In this article, we first survey recent progress towards Grauert-Riemenschneider type criteria. Secondly, we give a simplified proof of Boucksom's conjecture given by the author under the assumption that the Hermitian metric ω satisfies ■■ω^l=for all l, i.e., if T is a closed positive current on X such that ∫X Tcn/^n>0, then the class {T} is big and X is K?hler. Finally, as an easy observation, we point out that Nguyen's result can be generalized as follows:if ■■ω=0, and T is a closed positive current with analytic singularities, such that ∫X Tcn/^n>0, then the class {T} is big and X is Kahler. 展开更多
关键词 CLOSED POSITIVE CURRENT Demailly-Paun's CONJECTURE Boucksom's CONJECTURE KAHLER CURRENT Fujiki class
Research on optimal drive joints configuration of a rolling robot of closed fivebow-shaped-bar linkage 预览
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作者 Zeng Xiangkuo 《石化技术》 CAS 2019年第6期88-88,256共2页
The relationship between the stability and the configuration of the driving joint was studied as a measure to improve the stability of robot.The Lagrange dynamic equation of the robot was established.According to the ... The relationship between the stability and the configuration of the driving joint was studied as a measure to improve the stability of robot.The Lagrange dynamic equation of the robot was established.According to the principle of virtual work,the least squares solution of each joint torque was obtained.The relationship between the stability of the robot and the configuration of the driving joint is obtained by the sum of the norms of the joint torque.Finally,numerical simulations verify the correctness of the theory. 展开更多
关键词 CLOSED five-bow-shaped-bar parallel mechanism Lagrange equation DRIVE JOINTS CONFIGURATION
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封闭与开放的新闻教育——基于新闻写作课程改革的思考 预览
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作者 郝建国 《山西师大学报:社会科学版》 2019年第6期104-108,共5页
从传统的新闻写作到当下流行的非虚构写作,新闻教育一方面在适应外在环境的变化,另一方面也在坚守自成系统的运行规则。从社会学的视角看,这体现了社会系统的封闭性与开放性特点。新闻教育作为一个功能性的社会系统,既和外在环境有差异... 从传统的新闻写作到当下流行的非虚构写作,新闻教育一方面在适应外在环境的变化,另一方面也在坚守自成系统的运行规则。从社会学的视角看,这体现了社会系统的封闭性与开放性特点。新闻教育作为一个功能性的社会系统,既和外在环境有差异性,也需要外在环境提供运行的基本条件,但本质上是一个封闭运行的系统,自我生产,自我指涉。基于此,新闻教育应始终明确自己的边界,通过新闻文本规则教学与话语传播增强自身信息传播功能。刻意迎合环境变化并改变自身的运行规则,只会消解这种功能,动摇新闻教育的根本。 展开更多
关键词 新闻写作 封闭 开放 教育
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Experimental Study on Performance of a Closed Wet Cooling Tower for Air Wet-Bulb Temperature near 0℃
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作者 ZHOU Yasu ZHANG Pan +2 位作者 ZHAO Jingde YANG Honghai BAI Yufeng 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期1015-1023,共9页
Closed wet cooling towers(CWCTs) are used widely because of their better water quality and smaller water consumption. However, the operating parameters shown in the technical documents are only for rated conditions in... Closed wet cooling towers(CWCTs) are used widely because of their better water quality and smaller water consumption. However, the operating parameters shown in the technical documents are only for rated conditions in summer, not for any other conditions, especially in low air wet-bulb temperature areas such as those near 0℃. In addition, CWCTs often fail to achieve the designed cooling effect at low air wet-bulb temperatures. A experiment set of CWCT was built, and the performance of the CWCT at low air wet-bulb temperature near 0℃ was investigated. The impact of the operating parameters(air flow rate, cooling water flow rate, and spray water flow rate) on the heat and mass transfer performance of the CWCT was measured and analyzed. The results show the cooling performance of the CWCT at an air wet-bulb temperature 0℃, 2℃, and 4℃ is about 47%–63% of the rated operating condition;the optimal operating parameters of these conditions for the CWCT are just the same as those of the rated operating condition in summer. According to the experimental results, some operating advices are given. 展开更多
关键词 CLOSED wet COOLING TOWER performance of COOLING TOWER low AIR WET-BULB TEMPERATURE rated operating parameters evaluation index
闭合性胫骨远端关节外骨折的内固定术治疗进展
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作者 李杰辉 林焱斌 +3 位作者 余光书 张寿雄 刘友瑛 许宏滨 《中华外科杂志》 CAS CSCD 北大核心 2019年第3期236-240,共5页
胫骨远端关节外骨折多为高能量损伤,常为粉碎性骨折伴有明显移位和软组织损伤。由于该部位血液供应较差,并发症多,可严重影响患者生活质量。胫骨远端关节外骨折的治疗目标是恢复下肢力线,达到骨折愈合,获得良好的踝关节功能,减少并发症... 胫骨远端关节外骨折多为高能量损伤,常为粉碎性骨折伴有明显移位和软组织损伤。由于该部位血液供应较差,并发症多,可严重影响患者生活质量。胫骨远端关节外骨折的治疗目标是恢复下肢力线,达到骨折愈合,获得良好的踝关节功能,减少并发症发生。目前主张在局部条件允许的情况下行手术治疗,常见方法为钢板固定和髓内钉固定。本文结合国内外文献对闭合性胫骨远端关节外骨折的手术治疗方式进行综述,以期为临床治疗提供参考。 展开更多
关键词 胫骨骨折 骨折 闭合性 关节外骨折 钢板 髓内钉
用掌侧锁定钢板内固定术对老年闭合性不稳定型桡骨远端骨折患者进行治疗的效果探讨 预览
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作者 张峰炜 《当代医药论丛》 2019年第11期14-16,共3页
目的:研究用掌侧锁定钢板内固定术对老年闭合性不稳定型桡骨远端骨折患者进行治疗的效果。方法:选择新津县中医医院2017年4月至2018年4月接诊的80例老年闭合性不稳定型桡骨远端骨折患者作为研究对象。按照手术治疗方式的不同将其分为观... 目的:研究用掌侧锁定钢板内固定术对老年闭合性不稳定型桡骨远端骨折患者进行治疗的效果。方法:选择新津县中医医院2017年4月至2018年4月接诊的80例老年闭合性不稳定型桡骨远端骨折患者作为研究对象。按照手术治疗方式的不同将其分为观察组和对照组(40例/组)。为观察组患者应用掌侧锁定钢板内固定术进行治疗,为对照组患者应用常规的外固定术进行治疗。然后比较两组患者的各项术后恢复相关指标、腕关节的活动度和术后并发症的发生情况。结果:观察组患者治疗的总有效率高于对照组患者,其术后并发症的发生率低于对照组患者,P<0.05。治疗后,观察组患者的桡骨短缩值、关节面骨折块台阶值均小于对照组患者,其桡骨掌倾角及尺偏角、腕关节的背伸活动度、屈曲活动度、旋前活动度及旋后活动度均大于对照组患者,P<0.05。结论:用掌侧锁定钢板内固定术对老年闭合性不稳定型桡骨远端骨折患者进行治疗能够降低其术后并发症的发生率,促进其康复。 展开更多
关键词 老年 桡骨远端骨折 掌侧锁定钢板 闭合性 不稳定型
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An Analysis of Community Security in the New deal of Block system 预览
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作者 于欣宇 《校园英语》 2019年第9期253-254,共2页
"some opinions of the Central Committee of the Communist Party of China and the State Council on further strengthening the Management of Urban Planning and Construction" explicitly requires that new resident... "some opinions of the Central Committee of the Communist Party of China and the State Council on further strengthening the Management of Urban Planning and Construction" explicitly requires that new residential buildings should promote the block system and, in principle, no more closed residential areas should be built. The completed residential district and unit yard should be opened step by step to realize the publicity of the internal roads and to solve the problem of the layout of the traffic network. The community security problems caused by the pattern change of residential district is a brand-new topic in front of us. This article strengthens urban community governance from the aspects of building a government-led and community-centered multi-partner governance model, establishing public safety emergency mechanism under block system, and strengthening public safety education of citizens. 展开更多
关键词 block-based COMMUNITY CLOSED RESIDENTIAL DISTRICT COMMUNITY SAFETY
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Comparative analysis of the effects of gunpowder and plasma ignition in closed vessel tests 预览
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作者 Radoslaw Trebinski Zbigniew Leciejewski +1 位作者 Zbigniew Surma Jakub Michalski 《Defence Technology(防务技术)》 CAS CSCD 2019年第5期668-673,共6页
This paper presents the results of a comparative investigation into the effects of the ignition method on the ballistic properties of a single-base gun propellant,as determined via closed vessel tests.Conventional gun... This paper presents the results of a comparative investigation into the effects of the ignition method on the ballistic properties of a single-base gun propellant,as determined via closed vessel tests.Conventional gunpowder ignition and plasma jet ignition methods were used,and differences in the ignition time were analysed.The influence of the ignition method on the dynamic vivacity is discussed.It is shown that this influence is significant in the first phase of the combustion process,and with respect to the low values of the loading density.In the second phase of the combustion process,and for large values of the loading density,the dynamic vivacity plots for the two ignition methods converge.Regarding the burning law,close values of the exponent were obtained for the two ignition methods.The dynamic vivacity plots determined for plasma ignition reveal stronger dependence on the loading density than those determined for gunpowder ignition.The conclusion is that plasma ignition is not a solution to the problems inherent to the process of determining the ballistic properties of propellants,which results in deviation of the burning process from the geometric burning law. 展开更多
关键词 Closed vessel test Gun propellant Gunpowder ignition Plasma ignition
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锂离子电池电解液的密闭取样方法的研究 预览
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作者 桑俊利 韩艳娜 《天津化工》 CAS 2019年第2期14-16,共3页
电解液作为电池的四大关键材料之一,电解液中水,游离酸的含量对电池的品质有很大的影响。而取样方法决定样品检测指标的代表性,本文实验了两种电解液的取样方法,从而选出最优的密闭取样方法。
关键词 电解液 密闭 取样方法
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两种骨牵引针孔护理方法在下肢骨牵引患者中的应用效果
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作者 刘霞 杨丽 郝区平 《双足与保健》 2019年第4期7-8,共2页
目的对两种不同骨牵引针孔护理方法在下肢骨牵引患者中的临床运用情况加以分析与研究。方法按入院前后顺序,将该院2017年3月—2018年2月所收治的76例下肢骨牵引患者均分成甲乙两组,甲组采取开放式针孔护理措施,乙组采取封闭式针孔护理措... 目的对两种不同骨牵引针孔护理方法在下肢骨牵引患者中的临床运用情况加以分析与研究。方法按入院前后顺序,将该院2017年3月—2018年2月所收治的76例下肢骨牵引患者均分成甲乙两组,甲组采取开放式针孔护理措施,乙组采取封闭式针孔护理措施;比较两组患者的护理效果。结果乙组针孔感染率(7.9%)低于甲组(31.6%),差异有统计学意义(χ~2=3.671,P<0.05);就护理满意度而言,乙组(94.7%)高于甲组(78.9%),差异有统计学意义(χ~2=3.824,P<0.05)。结论对下肢骨牵引患者采取封闭式针孔护理方法 ,可减少针孔感染的发生,提升护理满意度,值得在临床上大力推行。 展开更多
关键词 下肢骨牵引 针孔护理 封闭式
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