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Submersible direct-drive progressing cavity pump rodless lifting technology 预览
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作者 HAO Zhongxian ZHU Shijia +4 位作者 PEI Xiaohan HUANG Peng TONG Zheng WANG Benyuan LI Deyin 《石油勘探与开发:英文版》 2019年第3期621-628,共8页
Submersible electrical motor direct-drive progressing cavity pump (PCP) rodless lifting was studied to solve the traditional rod-drive pump problems, such as rod-tubing wearing, low efficiency and short running time. ... Submersible electrical motor direct-drive progressing cavity pump (PCP) rodless lifting was studied to solve the traditional rod-drive pump problems, such as rod-tubing wearing, low efficiency and short running time. The theoretical researches and laboratory experiments of key tools such as submersible motor and the construction technology of lifting system were introduced. The field application and economic benefit were analyzed and compared with the traditional rod pumping unit. A new low speed and large torque permanent magnet synchronous motor was developed. This motor was used to drive PCP without gear reducer, which improved the reliability and feasibility. It can run at the speed from 50 to 500 r/min with stepless speed regulation, and it can perform high efficiency and large torque. Besides, other key supporting tools, such as motor protector and flex shaft, were developed. The submersible electrical motor direct- drive PCP technology can be used in a 139.7 mm (5.5 in) casing well, with daily output ranging from 5 to 50 m3. Until now, the technology has been deployed more than 100 wells. The field application results show that it eliminates the rod-tubing wearing and saves electric energy by more than 30% compared with the traditional rod pumping unit. And it also makes the oil produced in a safe and environmental friendly way. 展开更多
关键词 rodless artificial LIFT SUBMERSIBLE MOTOR DIRECT-DRIVE progressing CAVITY PUMP SUBMERSIBLE MOTOR artificial LIFT
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Heating frequency optimization for artificial feld-aligned scattering
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作者 吕立斌 吴振森 +4 位作者 李清亮 郝书吉 丁建 马广林 陈靓 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第9期52-57,共6页
In this study, we present a simulation study of artificial field-aligned irregularities(AFAI) to calculate the scattering coefficient considering a Gaussian autocorrelation function for the wave number spectrum of the... In this study, we present a simulation study of artificial field-aligned irregularities(AFAI) to calculate the scattering coefficient considering a Gaussian autocorrelation function for the wave number spectrum of the density fluctuation. By analyzing variations in the scattering coefficient under different ionospheric backgrounds, the optimal range of the heating frequency was found,which is about 0.9–1 times the critical frequency of the F2 layer. This is especially noticeable as when the heating frequency varies from 0.5 times to 0.9 times of the critical frequency, the scattering coefficient increases by 6.8–16.2 d B. These results should be useful for optimizing the heating frequency in the future artificial field-aligned scattering(AFAS) transmission applications at middle and low latitudes. 展开更多
关键词 artificial field-aligned SCATTERING artificial field-aligned IRREGULARITIES SCATTERING COEFFICIENT HEATING FREQUENCY
三通接头在人工气道患者气囊压力监测中的应用
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作者 余晶 李尊柱 +2 位作者 任美玲 孙巍 支琳琳 《中华现代护理杂志》 2019年第16期2011-2014,共4页
目的探讨三通接头在人工气道气囊压力监测中的应用.方法采用便利抽样法,选择2016年8月-2017年7月入住沈阳市第四人民医院重症医学科建立人工气道进行机械通气的患者85例,均采用最小压力封闭技术向气囊注气封闭气道.随机分成两组.观察组(... 目的探讨三通接头在人工气道气囊压力监测中的应用.方法采用便利抽样法,选择2016年8月-2017年7月入住沈阳市第四人民医院重症医学科建立人工气道进行机械通气的患者85例,均采用最小压力封闭技术向气囊注气封闭气道.随机分成两组.观察组(n=43)人工气道气囊连接三通接头,再连接气囊压力表监测气囊压力;对照组(n=42)人工气道直接连接气囊压力表监测气囊压力.监测两组患者充气后4、8、24、48 h气囊压力变化△P(△P=最小封闭压力-监测压力),观察患者返流误吸、气道黏膜损伤、肺部感染发生情况.结果两组充气4 h气囊压力变化差异无统计学意义[△P 4 h:(3.76±1.47)vs.(3.82±1.36)cmH2O,P>0.05],充气8、24、48 h观察组气囊压力变化较对照组小,差异均有统计学意义[△P 8 h:(5.76±2.58)vs.(7.29±2.42)cmH2O,24 h:(6.32±3.08)vs.(9.38±3.32)cmH2O,48 h:(8.79±5.26)vs.(15.32±5.87)cmH2O;P<0.01).观察组患者返流误吸发生率为9.3%,低于对照组的11.9%,差异有统计学意义(P<0.05);气道黏膜损伤及肺部感染发生率两组比较差异无统计学意义(P>0.05).结论使用三通接头可以有效减少人工气道气囊漏气现象,减少返流误吸的发生率. 展开更多
关键词 呼吸 人工 人工气道 气囊压力 测压法 三通接头
Best time for progesterone supplementation in aid ovulation induction cycles by letrozole
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作者 Xue-Mei Wang Hua Lou +3 位作者 Yuan-Rong Cui Xia Zhang Bo Dong Cai-Hong Chang 《海南医科大学学报(英文版)》 2019年第5期22-25,共4页
Objective:To explore the best time for progesterone supplementation in AID ovulation induction cycles by Letrozole.Methods: The data analysed in this study were collected from 509 patients who were performed AID (Arti... Objective:To explore the best time for progesterone supplementation in AID ovulation induction cycles by Letrozole.Methods: The data analysed in this study were collected from 509 patients who were performed AID (Artificial Insemination by Donor) administrated letrozole (LE) between 2014.8-2015.7. All patients were randomly divided into 4 groups by the time of progesterone administrated, including experimental group and the control group. The experimental group was divided into group 1-72 h after ovulation, group 2-48 h after ovulation, group 3-24 h after ovulation and control group—without administrated LE. The gestation and live birth rate were evaluated by monitoring vaginal ultrasound and HCG blood value 14 d after AID.Results: The pregnancy rate with administrated progesterone added 72 h after ovulation was 31.9%, which was significantly higher than those of other groups, the same situation as groups added progesterone was significantly higher than the control group. However, there was no significant difference in the numbers of abortions among the four groups. The LBR of group 4 was significantly lower than that of group 1.Conclutions: Progesterone administrated 72 h after ovulation can promoted the gestation rate, but did not affect the rate of miscarrage . 展开更多
关键词 PROGESTERONE LETROZOLE Artificial INSEMINATION DYDROGESTERONE CLOMIPHENE Citrate Artificial INSEMINATION by Donor(AID)
Artificial intelligence system of faster region-based convolutional neural network surpassing senior radiologists in evaluation of metastatic lymph nodes of rectal cancer
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作者 Lei Ding Guang-Wei Liu +11 位作者 Bao-Chun Zhao Yun-Peng Zhou Shuai Li Zheng-Dong Zhang Yu-Ting Guo Ai-Qin Li Yun Lu Hong-Wei Yao Wei-Tang Yuan Gui-Ying Wang Dian-Liang Zhang Lei Wang 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第4期379-387,共9页
Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primar... Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primary objective of this study was to comprehensively verify its accuracy in clinical use. Methods: Four hundred fourteen patients with rectal cancer discharged between January 2013 and March 2015 were collected from 6 clinical centers, and the magnetic resonance imaging data for pelvic metastatic LNs of each patient was identified by Faster R-CNN. Faster R-CNN based diagnoses were compared with radiologist based diagnoses and pathologist based diagnoses for methodological verification, using correlation analyses and consistency check. For clinical verification, the patients were retrospectively followed up by telephone for 36 months, with post-operative recurrence of rectal cancer as a clinical outcome;recurrence-free survivals of the patients were compared among different diagnostic groups, by methods of Kaplan-Meier and Cox hazards regression model. Results: Significant correlations were observed between any 2 factors among the numbers of metastatic LNs separately diagnosed by radiologists, Faster R-CNN and pathologists, as evidenced by rradiologist-Faster R-CNN of 0.912, rPathologist-radiologist of 0.134, and rPathologist-Faster R-CNN of 0.448 respectively. The value of kappa coefficient in N staging between Faster R-CNN and pathologists was 0.573, and this value between radiologists and pathologists was 0.473. The 3 groups of Faster R-CNN, radiologists and pathologists showed no significant differences in the recurrence-free survival time for stage N0 and N1 patients, but significant differences were found for stage N2 patients. Conclusion: Faster R-CNN surpasses radiologists in the evaluation of pelvic metastatic LNs of rectal cancer, but is not on par with pathologists. 展开更多
关键词 AI (Artificial Intelligence) Magnetic resonance imaging PATHOLOGY LYMPH NODES RECTAL cancer
Artificial intelligence on diabetic retinopathy diagnosis: an automatic classification method based on grey level co-occurrence matrix and naive Bayesian model
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作者 Kai Cao Jie Xu Wei-Qi Zhao 《国际眼科杂志:英文版》 SCIE CAS 2019年第7期1158-1162,共5页
AIM: To develop an automatic tool on screening diabetic retinopathy(DR) from diabetic patients.METHODS: We extracted textures from eye fundus images of each diabetes subject using grey level co-occurrence matrix metho... AIM: To develop an automatic tool on screening diabetic retinopathy(DR) from diabetic patients.METHODS: We extracted textures from eye fundus images of each diabetes subject using grey level co-occurrence matrix method and trained a Bayesian model based on these textures. The receiver operating characteristic(ROC) curve was used to estimate the sensitivity and specificity of the Bayesian model.RESULTS: A total of 1000 eyes fundus images from diabetic patients in which 298 eyes were diagnosed as DR by two ophthalmologists. The Bayesian model was trained using four extracted textures including contrast, entropy, angular second moment and correlation using a training dataset. The Bayesian model achieved a sensitivity of 0.949 and a specificity of 0.928 in the validation dataset. The area under the ROC curve was 0.938, and the 10-fold cross validation method showed that the average accuracy rate is 93.5%.CONCLUSION: Textures extracted by grey level cooccurrence can be useful information for DR diagnosis, and a trained Bayesian model based on these textures can be an effective tool for DR screening among diabetic patients. 展开更多
关键词 GREY level CO-OCCURRENCE matrix BAYESIAN textures artificial intelligence receiver operating characteristiccurve DIABETIC RETINOPATHY
A stable artificial protective layer for high capacity dendrite-free lithium metal anode
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作者 Zhipeng Wen Yueying Peng +5 位作者 Jianlong Cong Haiming Hua Yingxin Lin Jian Xiong Jing Zeng Jinbao Zhao 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第10期2535-2542,共8页
The metallic lithium(Li)is considered as the most promising anode material for high-e nergy batteries.Nevertheless,the uncon trollable growth of Li den drite and un stable electrolyte/electrode in terface still hin de... The metallic lithium(Li)is considered as the most promising anode material for high-e nergy batteries.Nevertheless,the uncon trollable growth of Li den drite and un stable electrolyte/electrode in terface still hin der the developme nt of Li-based battery.In this work,a no vel strategy has been proposed to stabilize Li anode by in-situ polymerizing polypyrrole(PPy)layer on Ni foam(PPy@Ni foam)as an artificial protective layer.The PPy protective layer can effectively decrease the contact between Li metal and electrolyte during cycling.In addition,the morphology characterization shows that the PPy layer can help the even Li deposition undemeath the layer,leading to a dendrite-free Li anode.As a result,when deposited 2 mAh-cm-2 Li metal,the PPy@Ni foam can keep stable Coulombic efficiency(99%)during nearly 250 cycles,much better than the pure Ni foam(100 cycles).Even in the case of the Li capacity of 10 mAh-cm-2,the stable cycling performance for 60 cycles can still be achieved.Furthermore,when assembled with LiFePO4 material as the cathode for a full cell,the PPy@Ni foam can keep high capacity retention of 85.5%at 500 cycles.In our work,we provide a simple and effective method to enhanee the electrochemical performances of Li metal-based batteries,and reveal a new avenue to design three-dimensional(3D)metallic curre nt collector for protecting the Li metal ano de. 展开更多
关键词 high capacity polypyrrole layer Li metal artificial protective layer dendrite-free anode
Two-dimensional materials for synaptic electronics and neuromorphic systems
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作者 Shuiyuan Wang David Wei Zhang Peng Zhou 《科学通报:英文版》 SCIE EI CSCD 2019年第15期1056-1066,共11页
Synapses in biology provide a variety of functions for the neural system. Artificial synaptic electronics that mimic the biological neuron functions are basic building blocks and developing novel artificial synapses i... Synapses in biology provide a variety of functions for the neural system. Artificial synaptic electronics that mimic the biological neuron functions are basic building blocks and developing novel artificial synapses is essential for neuromorphic computation. Inspired by the unique features of biological synapses that the basic connection components of the nervous system and the parallelism, low power consumption, fault tolerance, self-learning and robustness of biological neural systems, artificial synaptic electronics and neuromorphic systems have the potential to overcome the traditional von Neumann bottleneck and create a new paradigm for dealing with complex problems such as pattern recognition, image classification, decision making and associative learning. Nowadays, two-dimensional(2 D) materials have drawn great attention in simulating synaptic dynamic plasticity and neuromorphic computing with their unique properties. Here we describe the basic concepts of bio-synaptic plasticity and learning, the 2 D materials library and its preparation. We review recent advances in synaptic electronics and artificial neuromorphic systems based on 2 D materials and provide our perspective in utilizing 2 D materials to implement synaptic electronics and neuromorphic systems in hardware. 展开更多
关键词 Artificial SYNAPTIC ELECTRONICS Neuromorphic COMPUTATION 2D MATERIALS SYNAPTIC PLASTICITY Hebbian learning
Breeding and Reproduction of African Gray in Artificial Captivity 预览
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作者 Wang Jingjing 《动物与饲料科学:英文版》 CAS 2019年第2期77-79,共3页
The breeding process, management norms and reproduction measures of African gray were briefly introduced, and the problems in breed-ing environment and reproduction process were put forward, so as to provide a referen... The breeding process, management norms and reproduction measures of African gray were briefly introduced, and the problems in breed-ing environment and reproduction process were put forward, so as to provide a reference for captive breeding of African gray. 展开更多
关键词 AFRICAN GRAY BREEDING and REPRODUCTION Artificial CAPTIVITY
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桑菊清解汤对大鼠单肺通气肺损伤的影响 预览
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作者 刘小平 朱小兵 吴论 《北方药学》 2019年第1期149-150,共2页
目的:评价桑菊清解汤对大鼠单肺通气肺损伤的影响。方法:健康成年雄性SD大鼠48只,体重300~350g,随机分为4组(n=12):对照组(C组)、双肺通气组(S组)、单肺通气组(D组)和桑菊清解汤组(SJ组)。采用大潮气量通气建立肺损伤模型,D组和SJ组气... 目的:评价桑菊清解汤对大鼠单肺通气肺损伤的影响。方法:健康成年雄性SD大鼠48只,体重300~350g,随机分为4组(n=12):对照组(C组)、双肺通气组(S组)、单肺通气组(D组)和桑菊清解汤组(SJ组)。采用大潮气量通气建立肺损伤模型,D组和SJ组气管插管行右肺通气1h,潮气量5mL/kg,频率80次/min,I∶E 1∶2;C组行气管插管自主呼吸。采用桑菊清解汤300g灌胃,1次/d,于第10次灌胃后2h时开始制备模型;C组、S组及D组给予等容量生理盐水。于机械通气前(T0)、机械通气结束时(T1)、机械通气后30min(T2)时采集动脉血样,检测动脉血气,测定呼吸指数(RI)和氧合指数(OI)后处死大鼠,取肺组织,ELISA法检测肺组织TNF-a、IL-6和IL-10的含量,肺组织湿/干重比(W/D)和HO-1表达,观察肺组织病理学改变。结果:与C组比较,D组和SJ组肺组织TNF-a、IL-6、IL-10含量及W/D比升高,HO-1表达上调(P<0.05),S组各指标差异无统计学意义;与S组比较,D组和SJ组肺组织HO-1表达上调,TNF-a、IL-6、IL-10含量及W/D比升高,RI升高,OI降低(P<0.05)。与D组比较,SJ组肺组织、IL-10含量升高,TNF-a、IL-6含量及W/D比降低,HO-1表达上调,RI降低、OI升高(P<0.05)。结论:桑菊清解汤可通过上调肺组织HO-1的表达进而减轻大鼠单肺通气所致肺损伤。 展开更多
关键词 桑菊清解汤 呼吸 人工 血红素加氧酶-1
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Artificial tiger bone powder for improving the quality of life in elderly patients with fracture 预览
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作者 Li-You Wei Hong-Wei Zhang +1 位作者 Jin-Zeng Zuo Su-Miao Xu 《TMR传统医学研究》 2019年第4期213-221,共9页
Objective: To investigate the application of artificial tiger bone powder on fracture healing time, wrist functional recovery and quality of life (QOL) in elderly patients with distal radius fracture. Methods: The stu... Objective: To investigate the application of artificial tiger bone powder on fracture healing time, wrist functional recovery and quality of life (QOL) in elderly patients with distal radius fracture. Methods: The study was a randomised controlled trials performed from January 2015 to December 2016 in a hospital. Elderly patients with distal radius fracture were divided into the treatment and the control groups by the random sealed envelope method. All patients were given splint or plaster fixation after manipulative reduction, and functional exercise, the treatment group was also given artificial tiger bone powder orally (trade name: Jintiange capsule), the control group was given an oral placebo in their appearance and usage identical with the treatment group. Prior to treatment and 6, 12 months after treatment, the wrist function was assessed by range of motion, including flexion-extension, radial-ulnar and pronation-supination, and the QOL was assessed by the Mos 36-item Short Form Health Survey. Each patient's fracture healing time was recorded. Results: Before treatment, there were no significant differences in wrist function and QOL between the two groups. At 6 and 12 months after treatment, the wrist function and QOL in the treatment group were better than those in the control group, the differences were statistically significant (P < 0.05). The fracture healing time in the treatment group was shorter than that of the control group, and the difference was statistically significant (P < 0.05). Conclusion: The early usage of artificial tiger bone powder for elderly patients with distal radius fracture can promote the healing of fracture, recovery of wrist joint function, and ultimately improve the QOL for elderly patients. 展开更多
关键词 Artificial TIGER bone powder ELDERLY people DISTAL RADIUS FRACTURE WRIST function Quality of life
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有晶状体眼后房型人工晶状体植入术后前房角的改变
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作者 郑方方 王卫群 《中华眼外伤职业眼病杂志》 2019年第5期327-331,共5页
目的观察有晶状体眼后房型人工晶状体(ICL)植入术后前房角的改变。方法回顾性分析2017年12月至2018年9月接受有孔型有晶状体眼后房型人工晶状体(ICLV4c)植入术高度近视22例(41只眼)的临床资料。患者术前、术后1个月、3个月行Visante眼前... 目的观察有晶状体眼后房型人工晶状体(ICL)植入术后前房角的改变。方法回顾性分析2017年12月至2018年9月接受有孔型有晶状体眼后房型人工晶状体(ICLV4c)植入术高度近视22例(41只眼)的临床资料。患者术前、术后1个月、3个月行Visante眼前段OCT检查,观察比较术前、术后鼻侧和颞侧前房角开放度数(ACA),500μm和750μm房角开放距离(AOD500、AOD750),500μm和750μm小梁虹膜面积(TISA500、TISA750)。结果颞侧与鼻侧前房角各参数(ACA、AOD500、AOD750、TISA500、TISA750)相比差异均无统计学意义(P>0.05)。术前与术后前房角各参数相比,术后前房角各参数(ACA、AOD500、AOD750、TISA500、TISA750)较术前相比明显减少,差异有统计学意义(P<0.01)。术后1个月与术后3个月前房角各参数相比,差异无统计学意义(P>0.05)。结论有晶状体眼后房型人工晶状体植入术后前房角明显变窄,但是术后3个月随访期内前房角基本稳定。 展开更多
关键词 晶状体 人工 后房型 有晶状体眼 近视 高度 前房角开放度数 前房角开放距离 小梁虹膜面积
Artificial solid electrolyte interphase based on polyacrylonitrile for homogenous and dendrite-free deposition of lithium metal
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作者 徐航宇 李泉 +4 位作者 潘弘毅 邱纪亮 曹文卓 禹习谦 李泓 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第7期523-528,共6页
High chemical reactivity, large volume changes, and uncontrollable lithium dendrite growth have always been the key problems of lithium metal anodes.Coating has been demonstrated as an effective strategy to protect th... High chemical reactivity, large volume changes, and uncontrollable lithium dendrite growth have always been the key problems of lithium metal anodes.Coating has been demonstrated as an effective strategy to protect the lithium metal.In this work, the effects of polyacrylonitrile(PAN)-based coatings on electrodeposited lithium have been studied.Our results show that a PAN coating layer provides uniform and dendrite-free lithium deposition as well as better cycling performance with carbonate electrolyte.Notably, heat treatment of the PAN coating layer promotes the formation of larger deposit particle size and higher coulombic efficiency(85%).The compact coating layer of heat-treated PAN with a large Young modulus(82.7 GPa) may provide stable protection for the active lithium.Improved homogeneity of morphology and mechanical properties of heat-treated PAN contribute to the larger deposit particles.This work provides new feasibility to optimize the polymer coating through rational modification of polymers. 展开更多
关键词 LITHIUM deposition polymer coating artificial solid ELECTROLYTE INTERPHASE POLYACRYLONITRILE
Parallel Planning:A New Motion Planning Framework for Autonomous Driving 预览
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作者 Long Chen Xuemin Hu +3 位作者 Wei Tian Hong Wang Dongpu Cao Fei-Yue Wang 《自动化学报:英文版》 CSCD 2019年第1期236-246,共11页
Motion planning is one of the most significant technologies for autonomous driving. To make motion planning models able to learn from the environment and to deal with emergency situations, a new motion planning framew... Motion planning is one of the most significant technologies for autonomous driving. To make motion planning models able to learn from the environment and to deal with emergency situations, a new motion planning framework called as'parallel planning' is proposed in this paper. In order to generate sufficient and various training samples, artificial traffic scenes are firstly constructed based on the knowledge from the reality.A deep planning model which combines a convolutional neural network(CNN) with the Long Short-Term Memory module(LSTM) is developed to make planning decisions in an end-toend mode. This model can learn from both real and artificial traffic scenes and imitate the driving style of human drivers.Moreover, a parallel deep reinforcement learning approach is also presented to improve the robustness of planning model and reduce the error rate. To handle emergency situations, a hybrid generative model including a variational auto-encoder(VAE) and a generative adversarial network(GAN) is utilized to learn from virtual emergencies generated in artificial traffic scenes. While an autonomous vehicle is moving, the hybrid generative model generates multiple video clips in parallel, which correspond to different potential emergency scenarios. Simultaneously, the deep planning model makes planning decisions for both virtual and current real scenes. The final planning decision is determined by analysis of real observations. Leveraging the parallel planning approach, the planner is able to make rational decisions without heavy calculation burden when an emergency occurs. 展开更多
关键词 AUTONOMOUS driving artificial traffic SCENE deep learning EMERGENCIES motion PLANNING PARALLEL PLANNING
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护理干预用于人工关节置换术后早期康复锻炼的临床价值分析 预览
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作者 温玉虹 《世界最新医学信息文摘(电子版)》 2019年第25期25-26,共2页
目的 探讨护理干预用于人工关节置换术后早期康复锻炼的临床价值。方法 研究选取在2017年10月至2018年10月接诊的30例人工关节置换患者,随机分观察组15例(护理干预措施)、对照组15例(常规护理措施)。护理结束后比较两组人工关节置换患... 目的 探讨护理干预用于人工关节置换术后早期康复锻炼的临床价值。方法 研究选取在2017年10月至2018年10月接诊的30例人工关节置换患者,随机分观察组15例(护理干预措施)、对照组15例(常规护理措施)。护理结束后比较两组人工关节置换患者关节各时间段被、主动活动度及VAS评分指标。结果 观察组在治疗后关节各时间段被、主动活动度及VAS评分各项指标上均优于对照组且两组数据对比差异显著(P<0.05)。结论 应用护理干预措施可有效改善人工关节置换患者预后,疗效较佳。 展开更多
关键词 早期康复锻炼 关节置换术 人工 护理干预 临床价值
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机械通气患者拔管后吞咽障碍发生率及影响因素的Meta分析
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作者 胡英莉 蔡梦歆 史冬雷 《中华现代护理杂志》 2019年第17期2158-2163,共6页
目的系统分析机械通气患者拔管后吞咽障碍(PED)的发生率及影响因素。方法系统检索PubMed、CIHNAL、Cochrane Library、万方数据、CNKI、维普等数据库中关于PED的观察性研究。对所得文献进行筛选、提取资料、评价文献质量,采用Stata 14.... 目的系统分析机械通气患者拔管后吞咽障碍(PED)的发生率及影响因素。方法系统检索PubMed、CIHNAL、Cochrane Library、万方数据、CNKI、维普等数据库中关于PED的观察性研究。对所得文献进行筛选、提取资料、评价文献质量,采用Stata 14.0软件进行Meta分析。结果共检索文献1 356篇,筛选后纳入8项研究,其中队列研究5篇,横断面调查3篇;共包含2 384例研究对象,其中PED 553例。Meta分析结果显示,PED的总发生率为36%(95%CI:23%~50%),插管时间≥48 h患者PED的发生率为46%(95%CI:40%~53%);<48 h者PED的发生率为6%(95%CI:5%~7%)。插管时间和年龄是PED的独立影响因素。亚组分析结果显示插管时间<48 h者,年龄为影响因素(OR=2.18,95%CI:1.42~3.34),但插管时间是否为影响因素尚无法确定。插管时间≥48 h者,年龄(OR=1.02,95%CI:1.00~1.05)和插管时间(OR=1.28,95%CI:1.08~1.52)均为影响因素。发表偏倚分析纳入文献不存在明显偏倚,结果较为可靠。结论重视机械通气患者PED的问题,着重加强对插管时间≥48 h及年龄较大患者的关注,促进PED的早期发现和早期干预。 展开更多
关键词 META分析 呼吸 人工 拔管后吞咽障碍
机械通气诱发小鼠海马神经元凋亡与mTOR信号通路的关系
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作者 唐李娟 陈婷 +5 位作者 郑锋 陈畅 钟琦 张宗泽 彭勉 王焱林 《中华麻醉学杂志》 CAS CSCD 北大核心 2019年第4期422-424,共3页
目的评价机械通气诱发小鼠海马神经元凋亡与哺乳动物雷帕霉素靶蛋白(mTOR)信号通路的关系。方法健康雄性C57BL/6小鼠50只,8~10周龄,体重20~25 g,采用随机数字表法分为2组(n=25):对照组(C组)和机械通气组(V组)。C组自主呼吸,V组机械通气... 目的评价机械通气诱发小鼠海马神经元凋亡与哺乳动物雷帕霉素靶蛋白(mTOR)信号通路的关系。方法健康雄性C57BL/6小鼠50只,8~10周龄,体重20~25 g,采用随机数字表法分为2组(n=25):对照组(C组)和机械通气组(V组)。C组自主呼吸,V组机械通气6 h。机械通气结束后1和3 d时行旷场实验和场景恐惧实验。机械通气结束后1 d时取海马组织,采用Western blot法检测mTOR、磷酸化mTOR(p-mTOR)、微管相关蛋白1轻链3Ⅱ(LC3Ⅱ)的表达,计算p-mTOR/mTOR比值;采用TUNEL法检测海马神经元凋亡指数。结果与C组比较,V组中央区停留时间延长,跨格次数减少,僵直时间百分比降低,LC3Ⅱ表达上调,p-mTOR/mTOR比值和凋亡指数升高(P<0.05)。结论机械通气诱发小鼠海马神经元凋亡的机制可能与mTOR信号通路激活有关。 展开更多
关键词 呼吸 人工 细胞凋亡 受体作用蛋白丝氨酸苏氨酸激酶类 认知障碍
Modeling and compensation of hysteresis for pneumatic artificial muscles based on Gaussian mixture models
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作者 XU JiHao XIAO MuBang DING Ye 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第7期1094-1102,共9页
This paper presents a new data-driven model of length-pressure hysteresis of pneumatic artificial muscles(PAMs) based on Gaussian mixture models(GMMs). By ignoring the high-order dynamics, the hysteresis of PAMs is mo... This paper presents a new data-driven model of length-pressure hysteresis of pneumatic artificial muscles(PAMs) based on Gaussian mixture models(GMMs). By ignoring the high-order dynamics, the hysteresis of PAMs is modeled as a first-order nonlinear dynamical system based on GMMs, and inversion of the model is subsequently derived. Several verification experiments are conducted. Firstly, parameters of the model are identified under low-frequency triangle-wave pressure excitations.Then, pressure signals with different amplitudes, shapes and frequencies are applied to the PAM to test the prediction performance of the model. The proposed model shows advantages in identification efficiency and prediction precision compared with a generalized Prandtl–Ishlinskii(GPI) model and a modified generalized Prandtl–Ishlinskii(MGPI) model. Finally, the effectiveness of the inverse model is demonstrated by implementing the feedforward hysteresis compensation in trajectory tracking experiments. 展开更多
关键词 HYSTERESIS MODELING HYSTERESIS COMPENSATION pneumatic artificial muscles (PAMs) GAUSSIAN MIXTURE model (GMM)
心脏再同步化治疗应用轨道法植入左室心内膜电极的护理 预览
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作者 杜丽 程自平 +3 位作者 赵韧 陈刚 史学功 杨杰 《安徽医药》 CAS 2019年第8期1582-1585,共4页
目的总结心力衰竭(心衰)病人行轨道法植入心脏再同步化治疗(CRT)或者心脏再同步化治疗并心律转复除颤器(CRT-D)左室心内膜电极护理方法、疗效及术后并发症预防。方法选取2017年3月1日至2017年12月31日在安徽医科大学第一附属医院行CRT/C... 目的总结心力衰竭(心衰)病人行轨道法植入心脏再同步化治疗(CRT)或者心脏再同步化治疗并心律转复除颤器(CRT-D)左室心内膜电极护理方法、疗效及术后并发症预防。方法选取2017年3月1日至2017年12月31日在安徽医科大学第一附属医院行CRT/CRT-D左室心内膜电极植入术的心衰病人6例,采用轨道法先后建立股静脉-房间隔-股动脉轨道和股动脉-房间隔-锁骨下静脉轨道,并成功植入左室心内膜电极,采用优化护理方法,加强术中及术后心电监测,维持主动脉球囊反搏正常工作,加强术后抗凝治疗与监测。结果 6例病人术后1周随访,5例病人临床症状明显改善,临床治疗效果显著,1例轻度改善。1例病人发生左心室电极穿孔,床边心超示心包少量积液,予以左室电极重置后好转,其余无明显并发症。结论轨道法是植入心脏再同步化治疗左室心内膜电极的一种切实可行的术式。注重术中及术后心电监护及出凝血监测,加强主动脉球囊反搏护理监测,科学有效的临床护理是手术成功的关键之一。 展开更多
关键词 心力衰竭 心脏起搏 人工 除颤器 植入型 心内膜 电极 植入 围手术期护理 心脏再同步化治疗
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The structure of turbulent flow through submerged flexible vegetation 预览
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作者 Wen-xin Huai Jiao Zhang +3 位作者 Gabriel G.Katul Yong-guang Cheng Xue Tang Wei-jie Wang 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第2期274-292,共19页
The hydrodynamics of turbulent flow through submerged flexible vegetation is investigated in a flume using acoustic Doppler velocimetery(ADV)measurements.The flow characteristics such as the energetics and momentum tr... The hydrodynamics of turbulent flow through submerged flexible vegetation is investigated in a flume using acoustic Doppler velocimetery(ADV)measurements.The flow characteristics such as the energetics and momentum transfer derived from convcntional spectral and quadrant analyses are considered as the flow encounters a finite vegetation patch.Consistent with numerous canopy flow experiments,a shear layer and coherent vortex structures near the canopy top emerge caused by Kelvin-Helmholtz instabilities after the flow equilibrates with the vegetated layer.These in stabilities are commonly attributed to velocity differences between non-vegetated and vegetated canopy layers in agreement with numerous experiments and simulations conducted on dense rigid canopies.The power-spectral density function for vertical velocity turbulent fluctuations at different downstream positions starting from the edge of the vegetation layer are also computed.For a preset water depth,the dominant dimensionless frequency is found to be surprisingly invariant around 0.027 despite large differences in vegetation densities.The ejection and sweep events significantly contribute to the Reynolds stresses near the top of the vegetation.The momentum flux carried by ejections is larger than its counterpart carried by the sweeps above the canopy top.However,the momentum flux carried by sweeps is larger below the top of the canopy. 展开更多
关键词 Artificial flexible VEGETATION COHERENT VORTEX structures drag force open channel flow VELOCITY distribution
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