期刊文献+
共找到2,219篇文章
< 1 2 111 >
每页显示 20 50 100
The blocking effect of the sand fences quantified using wind tunnel simulations 被引量:6
1
作者 YU Yan-ping ZHANG Ke-cun +2 位作者 AN Zhi-shan WANG Tao HU Fei 《Journal of Mountain Science》 SCIE CSCD 2020年第10期2485-2496,共12页
Fences are one of the most effective measures to prevent and control wind-blown sand disasters,and the blocking effect of fences is largely determined by their porosity and height(H).This study employed wind tunnel ex... Fences are one of the most effective measures to prevent and control wind-blown sand disasters,and the blocking effect of fences is largely determined by their porosity and height(H).This study employed wind tunnel experiments to measure wind velocities on both sides of wire mesh sand fences with porosities of 75%,63%,56%,36%and heights of 10,5 and 2 cm.The effects of porosity and height on the blocking effect of the fences were evaluated on the basis of velocity variability,flow field,and the wind velocity reduction coefficient.Results show that the smaller the porosity,the stronger the blocking effect.The fence with a porosity of 36%had the strongest windproof efficiency of 0.70 and longest protection range of 9 H,and thus showed the best applicability in preventing and controlling wind-blown sand disasters.The fence with a porosity of 56%showed a windproof efficiency of 0.31 and a protection range of 7 H,which could be considered for adoption.However,fences with porosities of 75%and 63%were not recommended to be adopted,because their windproof efficiency and protection range were very small.Overall,the higher the fence,the stronger the blocking effect.The highest fence(10 cm)had the longest protection range of 90 cm,which was the best in application.Nevertheless,the 5 and 2 cm fences were almost consistent with 10 cm fence in windproof efficiency,which was still suitable for wind and sand fixation. 展开更多
关键词 Porous fence Fence height Windproof efficiency Protection range blocking effect
原文传递
Water blocking effect caused by the use of hydraulic methods for permeability enhancement in coal seams and methods for its removal 被引量:9
2
作者 Liu Qian Guo Yusen +2 位作者 An Fenghua Lin Luyao Lai Yongming 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期615-621,共7页
To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experimen... To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experiments were used to validate the effects of using surfactants;the results show that after dealing with vacuum saturation with water,the volume of micropores decreases,which results in a larger average pore size,and the volume of transitional pores,mesopores,macropores and total pores increases.Based on the distribution of pore size,the operation mode of ‘‘water infusion after gas extraction,then continuing gas extraction" is recommended to improve the volume of coal mine gas drainage.When the reflectance of vitrinite in coal samples is less than 1,using the surfactants Fast T,1631,APG,BS can mitigate the damage caused by the water blocking effect.But when the reflectance of vitrinite is larger than 1.4,the damage caused by the water blocking effect can be increased.When the surfactant CMC is used in hydraulic applications,the capillary forces of coal samples are almost negative,which means the capillary force is in the same direction as the gas extraction.The direction of capillary forces benefits the gas flow.So,using CMC can play an active role in removing the water blocking effect.Centrifugal experiments confirm that using CMC can effectively remove the water blocking effect,which has a beneficial effect on improving the gas drainage volume. 展开更多
关键词 Gas extraction Hydraulic measures Water blocking effect Capillary force Surfactant
在线阅读 下载PDF
Blocking Effects of Spleen Vaccine on Vertical Transmission of Classical Swine Fever Virus in Sows 被引量:1
3
作者 LIU Xin-ping GAO Lin +3 位作者 XU Jun-jie FENG Xuan-biao HUANG Jian-hua YANG Feng-mei 《Animal Husbandry and Feed Science》 CAS 2010年第5期24-25,28,共3页
[ Objective] To investigate the blocking effects of spleen vaccine on vertical transmission of classical swine fever virus (CSFV) in sows. [ Method] Sows infected by CSFV were selected from three large-scale pig far... [ Objective] To investigate the blocking effects of spleen vaccine on vertical transmission of classical swine fever virus (CSFV) in sows. [ Method] Sows infected by CSFV were selected from three large-scale pig farms and they were randomly divided into group Ⅰ, group Ⅱ and control group. The sows in the group Ⅰ were vaccinated with CSF spleen vaccine at a 1.5 times normal dose per pig; those in the group Ⅱ were vaccinated with CSF spleen vaccine at a 2.0 times normal dose per pig; and those in the control group were vaccinated with cell vaccine at a 4.0 times normal- dose per pig. The CSF antigens of piglets were detected by enzyme-linked immunosorbent assay (ELISA). [ Result] The antigen positive rate of piglets in the experimental group (18.5%) was significantly lower than that in the control group (48.1% ). No significant difference was found be- tween the group Ⅰ and the group Ⅱ. [ Condmion] CSF spleen vaccine has good blocking effects on vertical transmission of CSFV in sows. 展开更多
关键词 Classical swine fever spleen vaccine SOWS Vertical transmission blocking effects
在线阅读 下载PDF
The Blocking Effect of Phenolic Acid on N-Nitrosomorpholine Formation in vitro 被引量:2
4
作者 LI PlNG WANG HUAI-ZHOU WANG XU-QING AND WU YONG-NING(Institute of Nutrition and Food Hygiene, Chinese Academy of PreventiveMedicine, 29 Nanwei Road, Beijing 100050, China)( Present address: Institute of Environmental Health and Engineering, Chinese Acad 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第1期68-78,共11页
Phenolic acids (PAs) are widely found in many daily consumed vegetables and fruits.The inhibitory effects of PAs on Nnitrosomorpholine (NMOR) formation in vitro undersimulated gastric juice condition were studied. The... Phenolic acids (PAs) are widely found in many daily consumed vegetables and fruits.The inhibitory effects of PAs on Nnitrosomorpholine (NMOR) formation in vitro undersimulated gastric juice condition were studied. The results showed that the inhibjtoryIX)tency of thirteen varieties of PAs differed greatly, which may be related to theirchemical structures; the blocking rate (BR) of different killds of PAs were as follows:caf feic acid, 92.5%; tannic acid, 90.0%; gallic acid, 86.8%; sinaPinic acid, 86.2%; ferulicacid, 8l.l%; chlorogenic acid, 69.4%; gentisic acid, 69.2%; syringic acid, 62.1%; protocatechuic acid, 56.0%; p-coumaric acid, 52.5%; vannilic acid, 35.4%; moreover,p-hydroxybenzoic acid and m-coumaric acid had the least blocking effect or even slightcatalyzing effect. The results also demonstrated that amounts of NMOR formed werenegatively correlated with molar ratio of PAs to nitrite and that the optimum pH forinhibition was between 2 and 3. 展开更多
关键词 The blocking effect of Phenolic Acid on N-Nitrosomorpholine Formation in vitro
暂未订购
Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果比较 被引量:1
5
作者 黄飞 陈倩 张胜男 《中国现代医学杂志》 2025年第6期6-11,共6页
目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,... 目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,每组36例。对照组接受Twin-block功能矫治器联合自锁托槽治疗,研究组接受Pass矫治器治疗。对比两组临床疗效、颌牙排齐时间、硬组织头影测量指标[上中切牙轴与蝶鞍中心-鼻根点平面夹角(U1-SN)、下中切牙轴与鼻根点-上齿槽座点连接角(U1-NA)、上齿槽座点、鼻根点及下次槽座点连接角(ANB)、蝶鞍中心、鼻根点及上齿槽座点连接角(SNA)]、软组织头影测量目标[上唇到审美平面距离(TUL-FP)、下唇H线距、下唇到审美平面距离(TLL-FP)、鼻唇角]、矫治效果及患者满意度。结果研究组总有效率高于对照组(P<0.05)。研究组上颌牙排齐时间和下颌牙排齐时间均短于对照组(P<0.05)。两组治疗前后U1-SN、ANB、SNA、SNB的差值比较,差异无统计学意义(P>0.05)。研究组治疗前后U1-NA的差值高于对照组(P<0.05)。研究组治疗前后下唇H线距、TUL-FP、鼻唇角、TLL-FP的差值高于对照组(P<0.05)。研究组治疗前后同行评估等级指数(PAR)评分的差值高于对照组(P<0.05)。研究组满意度高于对照组(P<0.05)。结论相比于Twin-block功能矫治器联合自锁托槽,Pass矫治器治疗安氏Ⅱ类1分类错[牙合]畸形患者效果确切,可提高矫治效果,改善面部侧貌美学,缩短颌牙排齐时间,且患者满意度较高。 展开更多
关键词 安氏Ⅱ类1分类错[牙合]畸形 Pass矫治器 TWIN-block功能矫治器 自锁托槽 矫正效果
暂未订购
Blocking Response Surface Designs Incorporating Neigh-bour Effects
6
作者 Eldho Varghese Seema Jaggi 《Open Journal of Statistics》 2011年第3期199-204,共6页
In this paper, blocking in response surface for fitting first order model incorporating neighbour effects has been investigated. The conditions for orthogonal estimation of the parameters of the model have been obtain... In this paper, blocking in response surface for fitting first order model incorporating neighbour effects has been investigated. The conditions for orthogonal estimation of the parameters of the model have been obtained. A method of constructing designs which ensures the constancy of variance of the parameter estimates of the model has also been given. 展开更多
关键词 RESPONSE SURFACE Model Neighbour effectS blockING in RESPONSE SURFACE Conditions for ORTHOGONAL Estimation
在线阅读 下载PDF
Effect of Mg-Preflow for p-AlGaN Electron Blocking Layer on the Electroluminescence of Green LEDs with V-Shaped Pits
7
作者 Ai-Xing Li Chun-Lan Mo +5 位作者 Jian-Li Zhang Xiao-Lan Wang Xiao-Ming Wn Guang-Xu Wang Jun-Lin Liu Feng-Yi Jiang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第2期88-92,共5页
In GaN-based green light-emitting diodes(LEDs) with and without Mg-preflow before the growth of p-Al GaN electron blocking layer(EBL) are investigated experimentally.A higher Mg doping concentration is achieved in... In GaN-based green light-emitting diodes(LEDs) with and without Mg-preflow before the growth of p-Al GaN electron blocking layer(EBL) are investigated experimentally.A higher Mg doping concentration is achieved in the EBL after Mg-preflow treatment,effectively alleviating the commonly observed efficiency collapse and electrons overflowing at cryogenic temperatures.However,unexpected decline in quantum efficiency is observed after Mg-preflow treatment at room temperature.Our conclusions are drawn such that the efficiency decline is probably the result of different emission positions.Higher Mg doping concentration in the EBL after Mg-preflow treatment will make it easier for a hole to be injected into multiple quantum wells with emission closer to pGaN side through the(8-plane rather than the V-shape pits,which is not favorable to luminous efficiency due to the preferred occurrence of accumulated strain relaxation and structural defects in upper QWs closer to p-GaN.Within this framework,apparently disparate experimental observations regarding electroluminescence properties,in this work,are well reconciled. 展开更多
关键词 GaN EBL effect of Mg-Preflow for p-AlGaN Electron blocking Layer on the Electroluminescence of Green LEDs with V-Shaped Pits
原文传递
Left- and Right-Handers May Unintentionally Apply Different Cognitive Strategies in Response to Situational Demands: Study Using the Block-Wise Proportion Congruency Effect
8
作者 Kazuhito Yoshizaki Yurina Watanabe 《Journal of Behavioral and Brain Science》 2022年第1期10-21,共12页
We investigated the effects of handedness on developing latent cognitive response strategies according to situation variables. We used the findings of the block-wise Proportion Congruency (PC) effect in which the prop... We investigated the effects of handedness on developing latent cognitive response strategies according to situation variables. We used the findings of the block-wise Proportion Congruency (PC) effect in which the proportion of congruent trials in a given block modulates the compatibility effect in its block. The block-wise PC effect cannot be intentionally controlled. A Simon task with three different types of Proportion Congruency (PC) in a given block was used to measure the block-wise PC effects. This task was administered to 24 left-handed and 24 right-handed participants. The reaction time and error rates, consistent with previous studies, demonstrated that the block-wise PC effect was observed in left- and right-handers. Crucially, the block-wise PC effect was more pronounced in left- than right-handers, suggesting that left- and right-handers unintentionally apply different cognitive strategies in response to conflict resolution experiences. 展开更多
关键词 Cognitive Control HANDEDNESS block-Wise Proportion Congruency (PC) effect
在线阅读 下载PDF
单孔胸腔镜肺部手术采用肋间神经阻滞与局部切口封闭镇痛效果的比较
9
作者 郝磊 《中外医学研究》 2026年第2期12-15,共4页
目的:比较单孔胸腔镜肺部手术中肋间神经阻滞、局部切口封闭的镇痛效果。方法:选取2023年1月—2024年12月太仓市中医医院收治的76例行单孔胸腔镜肺部手术患者,采用随机数表法分为A、B两组,每组各38例。A组采用肋间神经阻滞镇痛,B组采用... 目的:比较单孔胸腔镜肺部手术中肋间神经阻滞、局部切口封闭的镇痛效果。方法:选取2023年1月—2024年12月太仓市中医医院收治的76例行单孔胸腔镜肺部手术患者,采用随机数表法分为A、B两组,每组各38例。A组采用肋间神经阻滞镇痛,B组采用局部切口封闭镇痛。对两组术后不同时间点的疼痛视觉模拟评分(VAS)、Ramsay镇静评分量表(RSS)、镇痛药物使用情况及并发症发生情况进行监测与记录。结果:术后6 h、12 h、24 h、48 h,在静息状态和咳嗽状态下,A组VAS评分明显低于B组,两组比较,差异具有统计学意义(P<0.05)。此外,在术后12 h和24 h时,A组RSS评分明显低于B组,差异具有统计学意义(P<0.05)。A组术后PCIA首次按压时间明显晚于B组,术后24 h和48 h有效按压次数和补救镇痛次数比B组明显减少,且48 h镇痛药物使用量明显低于B组,差异有统计学意义(P<0.05)。术后A组发生头晕头痛(7.89%)、尿潴留(2.63%)、肺不张(5.26%)、心律失常(2.63%)的发生率略高于B组,两组比较差异无统计学意义(P>0.05)。结论:在单孔胸腔镜肺部手术中,肋间神经阻滞的镇痛效果优于局部切口封闭,能更有效减轻患者术后疼痛,减少镇痛药物使用,且不增加并发症发生率。 展开更多
关键词 单孔胸腔镜肺部手术 肋间神经阻滞 局部切口封闭 镇痛效果
暂未订购
超声引导下四种腰方肌阻滞入路对腹腔镜全子宫切除术患者镇痛效果的随机对照研究
10
作者 王梅静 韦余琴 +1 位作者 任善洁 刘幸幸 《中国实用医药》 2026年第7期36-40,共5页
目的比较超声引导下四种不同腰方肌阻滞入路(QLB)对腹腔镜全子宫切除术患者围术期镇痛效果的影响。方法200例行腹腔镜全子宫切除术的患者,按照随机数字表法将患者分为五组:Q1组、Q2组、Q3组、Q4组和C组,每组40例。术中穿刺靶点:Q1组(后... 目的比较超声引导下四种不同腰方肌阻滞入路(QLB)对腹腔镜全子宫切除术患者围术期镇痛效果的影响。方法200例行腹腔镜全子宫切除术的患者,按照随机数字表法将患者分为五组:Q1组、Q2组、Q3组、Q4组和C组,每组40例。术中穿刺靶点:Q1组(后路):腰方肌后表面与腹横肌筋膜之间;Q2组(外侧路):腰方肌后表面、竖脊肌外侧的“腰筋膜三角”区域;Q3组(前路):腰方肌与腰大肌之间的间隙;Q4组(肌内入路):腰方肌肌肉组织内;C组(对照组):不予任何神经阻滞。对比五组术中阿片类药物用量、术后镇痛视觉模拟评分法(VAS)评分、术后不良事件发生情况。结果五组术中舒芬太尼、瑞芬太尼用量对比有统计学差异(P<0.05);Q1、Q2、Q3、Q4组术中舒芬太尼用量[(5.63±4.96)、(3.13±3.70)、(1.25±2.47)、(6.25±5.40)μg]和瑞芬太尼用量[(1.41±0.29)、(1.22±0.25)、(0.83±0.20)、(1.62±0.28)mg]明显少于C组[(9.38±5.79)μg、(2.05±0.37)mg],且Q3组术中舒芬太尼用量和瑞芬太尼用量明显少于Q1、Q2、Q4组,对比有统计学差异(P<0.05);而五组术中丙泊酚用量对比无明显差异(P>0.05)。Q1、Q2、Q3、Q4组术后即刻、术后6 h、术后12 h、术后24 h的静息及动态VAS评分均明显低于C组,且Q3组低于Q1、Q2、Q4组,对比有统计学差异(P<0.05)。五组术后不良事件(恶心/呕吐、尿潴留、肌力减退、感觉减退)发生率均较低,对比无明显差异(P>0.05)。结论四种入路的腰方肌阻滞均能为腹腔镜全子宫切除术提供有效的镇痛并减少阿片类药物用量,尤以前路入路的效果最为显著。 展开更多
关键词 超声引导 腰方肌阻滞入路 腹腔镜全子宫切除术 镇痛效果
暂未订购
Mechanisms of shale hydration and water block removal 被引量:3
11
作者 ZENG Fanhui ZHANG Qiang +3 位作者 GUO Jianchun ZENG Bo ZHANG Yu HE Songgen 《Petroleum Exploration and Development》 CSCD 2021年第3期752-761,共10页
Shale samples of Silurian Longmaxi Formation in the Changning area of the Sichuan Basin, SW China, were selected to carry out scanning electron microscopy, CT imaging, high-pressure mercury injection, low-temperature ... Shale samples of Silurian Longmaxi Formation in the Changning area of the Sichuan Basin, SW China, were selected to carry out scanning electron microscopy, CT imaging, high-pressure mercury injection, low-temperature nitrogen adsorption and imbibition experiments to compare the hydration characteristics of montmorillonite and illite, analyze the main factors affecting the water block removal of shale, and reveal the mechanisms of pore structure evolution during shale hydration. The hydration characteristics of shale are closely related to the composition of clay minerals, the shale with high illite content is not susceptible to hydration and thus has limited room for pore structure improvement;the shale with high montmorillonite is susceptible to hydration expansion and thus has higher potential of pore structure improvement by stimulation;the shale with high illite content has stronger imbibition in the initial stage, but insufficient diffusion ability, and thus is likely to have water block;the shale with high montmorillonite content has weaker imbibition in the initial stage but better water diffusion, so water blocking in this kind of shale can be removed to some degree;the shale reservoir has an optimal hydration time, when it is best in physical properties, but hydration time too long would cause damage to the reservoir, and the shale with high illite content has a shorter optimal hydration time;inorganic cations can inhibit the hydration of clay minerals and have stronger inhibition to illite expansion, especially K^(+);for the reservoir with high content of montmorillonite, the cation content of fracturing fluid can be lowered to promote the shale hydration;fracturing fluid with high K^(+) content can be injected into reservoirs with high illite content to suppress hydration. 展开更多
关键词 SHALE clay minerals HYDRATION microscopic pore structure water block effect fracturing fluid diffusion optimal hydration time water block removal
在线阅读 下载PDF
纳布啡复合局麻药对臂丛阻滞上肢骨科手术的麻醉镇痛效果
12
作者 谢燕 曹杏 +2 位作者 圣春平 鲍冬梅 王立锁 《中国药物应用与监测》 2026年第1期42-46,共5页
目的 探讨纳布啡复合局麻药物行臂丛神经阻滞麻醉对上肢骨科手术患者麻醉效果及术后镇痛的影响。方法 采取前瞻性研究,选取2023年1月至2025年4月东台市中医院108例拟行上肢骨科手术的患者,采用随机数字表法将其分为N组(罗哌卡因+利多卡... 目的 探讨纳布啡复合局麻药物行臂丛神经阻滞麻醉对上肢骨科手术患者麻醉效果及术后镇痛的影响。方法 采取前瞻性研究,选取2023年1月至2025年4月东台市中医院108例拟行上肢骨科手术的患者,采用随机数字表法将其分为N组(罗哌卡因+利多卡因+纳布啡)、D组(罗哌卡因+利多卡因+地塞米松)和S组(罗哌卡因+利多卡因),每组36例。比较3组麻醉效果(感觉阻滞起效时间、运动阻滞起效时间、镇痛持续时间)、术后疼痛程度[视觉模拟评分法(VAS)评分]、血流动力学指标(心率、平均动脉压)及围手术期发生的不良反应。结果 N组、D组及S组比较,感觉阻滞起效时间[(2.97±0.90)、(4.05±1.03)、(5.20±1.37)min]和运动阻滞起效时间[(8.91±2.76)、(11.22±2.80)、(13.63±3.14)min]逐渐延长(F=35.838、23.763,均P<0.05),镇痛持续时间[(11.06±1.27)、(8.42±1.10)、(7.21±1.08)h]逐渐缩短(F=104.934,P<0.05)。术后2、4、8、12 h的VAS评分,N组[(1.34±0.44)、(1.57±0.46)、(1.88±0.51)、(2.84±1.27)分]、D组[(1.51±0.50)、(1.85±0.52)、(2.85±0.62)、(3.69±1.32)分]、S组[(1.87±0.61)、(2.17±0.72)、(3.06±0.93)、(4.55±1.44)分]比较逐渐升高(F=9.696、9.731、28.351、14.543,均P<0.05)。T_(2)时的心率,N组[(81.35±9.14)次/min]、D组[(84.42±8.95)次/min]、S组[(87.62±8.93)次/min]逐渐升高(F=4.362,P<0.05);T_(3)时的平均动脉压,N组[(87.51±6.22)mmHg(1 mmHg=0.133 kPa)]、D组[(88.85±6.37)mmHg]、S组[(92.19±7.23)mmHg]逐渐升高(F=4.769,P<0.05)。围手术期不良反应发生率,N组[13.89%(5/36)]与D组[11.11%(4/36)]、S组[2.78%(1/36)]比较,差异无统计学意义(Fisher精确检验,P=0.266)。结论 纳布啡复合局麻药物行臂丛神经阻滞效果最优,地塞米松复合局麻药物效果优于单独局麻药物,3种方案安全性相当。 展开更多
关键词 纳布啡 罗哌卡因 利多卡因 臂丛神经阻滞 上肢骨科手术 术后镇痛 麻醉效果
暂未订购
道路绿化配置设计对空气颗粒污染物扩散的影响研究
13
作者 许贻艺 黄琴琴 《环境科学与管理》 2026年第2期59-64,共6页
为通过优化城市道路绿化设计改善局部空气质量提供科学依据,展开道路绿化配置设计对空气颗粒污染物扩散的影响研究。分析构成空气颗粒污染的主要污染物的日浓度变化情况;选取车流量、空气温度、最大风速等作为小环境因子指标,分析气候... 为通过优化城市道路绿化设计改善局部空气质量提供科学依据,展开道路绿化配置设计对空气颗粒污染物扩散的影响研究。分析构成空气颗粒污染的主要污染物的日浓度变化情况;选取车流量、空气温度、最大风速等作为小环境因子指标,分析气候环境对污染物扩散产生的影响;选取六条具有典型性的道路,分析不同道路绿化配置对空气颗粒污染物扩散的影响。研究结果表明,空气颗粒污染物的日浓度变化表现为先降低后增大的特点;不同季节内气候小环境对污染物扩散产生的影响均不相同;冬季道路绿化对颗粒污染物的阻滞作用并不明显,夏季较为明显。 展开更多
关键词 道路绿化配置 空气颗粒污染物 气候小环境 阻滞作用 污染物扩散
在线阅读 下载PDF
超声引导下改良髂筋膜间隙阻滞在老年髋部骨折患者摆放体位过程中的阻滞效果研究
14
作者 秦华 《中国实用医药》 2026年第1期36-39,共4页
目的分析老年髋部骨折患者摆放体位过程中应用超声引导下改良髂筋膜间隙阻滞的效果。方法选择60例老年髋部骨折患者,以随机数字表法分为对照组(传统髂筋膜间隙阻滞)与研究组(超声引导下改良髂筋膜间隙阻滞)。对比两组的阻滞起效时间、... 目的分析老年髋部骨折患者摆放体位过程中应用超声引导下改良髂筋膜间隙阻滞的效果。方法选择60例老年髋部骨折患者,以随机数字表法分为对照组(传统髂筋膜间隙阻滞)与研究组(超声引导下改良髂筋膜间隙阻滞)。对比两组的阻滞起效时间、阻滞完善率、疼痛情况、不良事件发生情况及生命体征指标。结果研究组阻滞起效时间为(5.22±1.05)min,比对照组的(8.57±1.24)min更短(P<0.05);研究组阻滞完善率93.33%(28/30)较对照组的73.33%(22/30)更高(P<0.05)。体位摆放中、摆放后,研究组视觉模拟评分法(VAS)评分(2.14±0.53)、(1.22±0.31)分较对照组的(4.75±0.72)、(3.15±0.61)分更低(P<0.05)。研究组不良事件发生率6.7%明显比对照组的26.7%低(P<0.05)。体位摆放前,两组血压、心率对比无差异(P>0.05);体位摆放中、摆放后,研究组血压、心率波动幅度小于对照组(P<0.05)。结论将超声引导下改良髂筋膜间隙阻滞用于老年髋部骨折患者摆放体位过程中具有良好的阻滞效果,能够快速起效,提高阻滞完善率,有效减轻患者疼痛,降低不良事件发生率,且对患者生命体征影响较小,有利于患者在摆放体位过程中的生理稳定,应用价值高。 展开更多
关键词 超声引导 改良髂筋膜间隙阻滞 髋部骨折 体位摆放 阻滞效果 老年
暂未订购
超声引导下肩关节囊周神经阻滞与肌间沟臂丛神经阻滞在肩关节镜术后恢复效果的比较
15
作者 吴剑平 徐佳 +2 位作者 裴大庆 朱志鹏 吴城 《中国现代医学杂志》 2026年第4期108-114,共7页
目的探讨超声引导下肩关节囊周神经阻滞(PENG)与肌间沟臂丛神经阻滞(ISB)在肩关节镜术后恢复的效果。方法采用非劣效性研究设计,选取2023年1月—2024年6月于嘉兴市第二医院行单侧肩关节镜下肩袖修补手术的190例患者,按照区组随机化的方... 目的探讨超声引导下肩关节囊周神经阻滞(PENG)与肌间沟臂丛神经阻滞(ISB)在肩关节镜术后恢复的效果。方法采用非劣效性研究设计,选取2023年1月—2024年6月于嘉兴市第二医院行单侧肩关节镜下肩袖修补手术的190例患者,按照区组随机化的方法随机分为PENG组、ISB组,各95例。术后PENG组失访6例,ISB组失访4例,最终研究纳入PENG组89例、ISB组91例。比较两组术后恢复质量评定量表(QoR-40)评分、疼痛数字评分量表(NRS)评分、第1次镇痛补救时间、镇痛补救率、术后镇痛泵按压次数、麻醉剂用量及不良反应。结果PENG组治疗前与术后24 h QoR-40评分的差值小于ISB组(P<0.05)。PENG组与ISB组术后30 min和4、8、12、24、48 h静息状态NRS评分比较,结果:①不同时间点NRS评分比较,差异有统计学意义(P<0.05);②PENG组与ISB组NRS评分比较,差异有统计学意义(P<0.05),PENG组NRS评分更低;③两组NRS评分变化趋势比较,差异有统计学意义(P<0.05)。PENG组补救镇痛率低于ISB组(P<0.05),镇痛泵按压次数少于ISB组(P<0.05)。PENG组术后反跳痛发生率低于ISB组(P<0.05)。结论超声引导下肩关节PENG在肩关节镜术后的恢复效果与ISB相当;PENG对RCI患者可实现有效镇痛,且安全性良好。 展开更多
关键词 肩关节镜手术 囊周神经阻滞 肌间沟臂丛神经阻滞 恢复效果 非劣性
暂未订购
矿山采空塌陷区岩溶垂向充水通道水平帷幕构建与效果监测
16
作者 高学通 王志奇 薛晓峰 《有色金属(矿山部分)》 2026年第1期116-124,共9页
矿山防治水帷幕注浆一般包括地面和井下近矿体帷幕注浆两种技术,在金属非金属大水矿山防治水工程中得到了广泛应用并取得良好效果。某铁多金属矿因采空塌陷导通第四系砂砾卵石强富水层地下水,加之下伏结晶灰岩岩溶发育,第四系水通过冒... 矿山防治水帷幕注浆一般包括地面和井下近矿体帷幕注浆两种技术,在金属非金属大水矿山防治水工程中得到了广泛应用并取得良好效果。某铁多金属矿因采空塌陷导通第四系砂砾卵石强富水层地下水,加之下伏结晶灰岩岩溶发育,第四系水通过冒落带和岩溶充水通道溃入井下导致淹井事故,由于缺少矿体底板相对隔水层且矿体空间分布形态特殊,难以采用常规帷幕注浆技术。通过查明矿区充水通道和相对隔水层空间分布特征,在精确刻画矿区水文地质模型基础上,针对灰岩岩溶发育区域构建水平注浆帷幕,切断第四系水与基岩含水层间水力联系,大幅降低矿坑涌水量。基于水平帷幕分布形态和阻渗特征,布设了光纤变形与水位监测相结合的幕体阻渗效果空间监测预警系统,有效保证了幕体阻水效果和矿山安全开采。 展开更多
关键词 采空塌陷 岩溶充水通道 地面帷幕注浆 近矿体帷幕注浆 水平阻渗帷幕 效果监测
在线阅读 下载PDF
Effect of specifically-adsorbed polysulfides on the electron transfer kinetics of sodium metal anodes 被引量:1
17
作者 Huazhao Yang Yu Li +3 位作者 Xianxian Zhou Xiaotao Ma Donghong Duan Shibin Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第11期26-33,I0003,共9页
Room-temperature sodium-sulfur(RT Na-S)batteries hold great promise for large-scale energy storage applications owing to the high energy density and earth-abundance of Na and S.However,the dissolution and migration of... Room-temperature sodium-sulfur(RT Na-S)batteries hold great promise for large-scale energy storage applications owing to the high energy density and earth-abundance of Na and S.However,the dissolution and migration of sodium polysulfides,uncontrollable Na dendrite growth,and the lack of studies on Na electrodeposition kinetics have hindered the development of these batteries.Herein,we reveal the mechanism of sodium polysulfides on the Na plating/stripping kinetics using a three-electrode system.First,the kinetic behavior deviates from the commonly supposed Butler-Volmer model,which is well described by the Marcus model.In addition,the specific adsorption of polysulfides on the sodium electrode surface is a key factor influencing the kinetics.Higher-order polysulfides(S_(8)^(2-)and S_(6)^(2-))exhibit distinct specific adsorption behaviors because of their high adsorption energies compared to lower-order polysulfides(S_(4)^(2-)and S_(2)^(2-)).The electrostatic effect caused by specific adsorption can accelerate the kinetics,whereas the blocking effect can slow the kinetics.Thus,this competitive relationship enables low concentrations of high-order polysulfides to stimulate kinetics.This implies that a weak shuttle effect is beneficial for obtaining a stable Na deposition in RT Na-S batteries.An in-depth understanding of the Na electrodeposition kinetics provides beneficial clues for future metal sodium/electrolyte interface designs. 展开更多
关键词 Sodium anode kinetics POLYSULFIDES Specific adsorption The electrostatic effect The blocking effect
在线阅读 下载PDF
亚甲蓝复合罗哌卡因行髂筋膜阻滞用于老年髋关节置换术病人术后镇痛的半数有效剂量和不良反应分析
18
作者 张扬 杨顺 +1 位作者 陆咨儒 沙荔荔 《实用老年医学》 2026年第2期154-158,共5页
目的测定亚甲蓝作为局麻药佐剂与罗哌卡因复合应用于老年髂筋膜阻滞在髋关节置换术病人术后24 h有效镇痛和不影响下肢肌力的半数有效剂量(ED_(50))及95%有效剂量(ED_(95)),并观察病人术后24 h的不良反应。方法选取泰州市姜堰中医院2024... 目的测定亚甲蓝作为局麻药佐剂与罗哌卡因复合应用于老年髂筋膜阻滞在髋关节置换术病人术后24 h有效镇痛和不影响下肢肌力的半数有效剂量(ED_(50))及95%有效剂量(ED_(95)),并观察病人术后24 h的不良反应。方法选取泰州市姜堰中医院2024年7—11月择期行全髋关节置换术的老年病人29例,在全麻诱导前行超声引导下髂筋膜阻滞,注射药液为不同剂量的亚甲蓝复合0.25%罗哌卡因共30 mL。首例病人使用亚甲蓝剂量为40 mg,使用Dixon序贯法确定下一例病人使用亚甲蓝的剂量,若前一例病人在术后24 h内出现股四头肌肌力≥4分,同时静息VAS评分≤1分,且活动时VAS评分≤3分,则下一例病人降低一个阶梯的亚甲蓝剂量,反之,增加一个阶梯剂量,直至出现7个交叉点时研究终止。采用Probit回归分析法计算亚甲蓝的ED_(50)、ED_(95)及其95%CI。同时观察髋关节置换术后24 h的不良反应。结果亚甲蓝复合罗哌卡因行髂筋膜阻滞在老年髋关节置换术后能有效镇痛且不影响下肢肌力的ED_(50)为26.956 mg(95%CI:18.929~32.231 mg),ED_(95)为40.070 mg(95%CI:33.878~84.708 mg)。髋关节置换术后24 h内,有2例病人需要额外使用镇痛药物,均出现在使用低于ED_(50)剂量时。仅有1例病人出现下肢无力而无法下床走动,亚甲蓝的使用剂量为20 mg。没有病人因为术后肌无力而出现摔倒现象。所有病人均未出现神经损伤、穿刺点感染及药物中毒等神经阻滞并发症。结论亚甲蓝复合罗哌卡因行髂筋膜阻滞在老年髋关节置换术术后镇痛的ED_(50)为26.956 mg,ED_(95)为40.070 mg,同时,亚甲蓝没有增加罗哌卡因的运动阻滞风险,术后不良反应发生率低。 展开更多
关键词 亚甲蓝 髂筋膜阻滞 髋关节置换 老年人 半数有效剂量 95%有效剂量
暂未订购
Preparation of Polyacrylate-based Conductive Coatings and Its PTC Effect 被引量:3
19
作者 熊传溪 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第1期26-29,共4页
Polyacrylate-based conductive coatings were prepared from polyacrylate emulsion as matrix and carbon black (CB) whose surface was treated with titanate coupling agent as conducting particles.One kind of organic crysta... Polyacrylate-based conductive coatings were prepared from polyacrylate emulsion as matrix and carbon black (CB) whose surface was treated with titanate coupling agent as conducting particles.One kind of organic crystal was added to study its effects on the electrical conductivity and PTC(positive temperature coefficient)effect of the conductive coatings.Experimental results show that the coatings containing only polyacrylate emulsion and CB exhibit an excellent electrical conductivity but bad PTC effect,and when organic crystal is added,PTC effect is characterized and can increase by 2 orders of magtitude.The critical transformation temperature of polyacrylate emulsion/CB PTC composites is decided by melting point of organic crystals. 展开更多
关键词 carbon block PTC effect organic crystal
在线阅读 下载PDF
超声引导下罗哌卡因多点注射髂筋膜间隙阻滞在老年全髋关节置换术中的应用
20
作者 刘志云 张扬 +1 位作者 杨顺 殷红 《西北药学杂志》 2026年第1期237-243,共7页
目的探究超声引导下的罗哌卡因多点注射髂筋膜间隙阻滞(fascia iliaca compartment block,FICB)在老年患者全髋关节置换术(total hip arthroplasty,THA)中应用的效果。方法选取2023年1月至2024年12月医院收治的行THA术的老年患者80例作... 目的探究超声引导下的罗哌卡因多点注射髂筋膜间隙阻滞(fascia iliaca compartment block,FICB)在老年患者全髋关节置换术(total hip arthroplasty,THA)中应用的效果。方法选取2023年1月至2024年12月医院收治的行THA术的老年患者80例作为研究对象,根据注射方法的不同分为甲组(给予单点注射,n=39例)、乙组(给予多点注射,n=41例)。比较2组患者的麻醉效果、血流动力学指标[心率(heart rate,HR)和平均动脉压(mean arterial pressure,MAP)]、疼痛情况[视觉模拟评分法(Visual Analogue Scales,VAS)、成人疼痛行为量表(Adult Pain Behavioral Scale,APBS)]和不良反应的发生情况。结果乙组的麻醉效果优于甲组,术后需要使用镇痛药物辅助镇痛例数少于甲组(P<0.05)。2组神经阻滞完成后20 min、术后6 h的HR和MAP水平较神经阻滞前均降低,且乙组以上各指标的水平均低于甲组(P<0.05)。与入室时比较,2组术后12 h、术后24 h的VAS、APBS评分均降低(P<0.05),与术后12 h时比较,2组术后24 h的VAS、APBS评分均升高,但乙组的VAS、APBS评分均低于甲组(P<0.05);2组患者不良反应发生情况比较差异无统计学意义(P>0.05)。结论与单点注射相比,超声引导下的罗哌卡因多点注射FICB用于老年患者THA术中的阻滞效果更佳,同时更能稳定血流动力学水平,减轻术后疼痛,且具有较高的安全性,值得临床推广和应用。 展开更多
关键词 罗哌卡因 超声引导 髂筋膜间隙阻滞 老年 全髋关节置换术 麻醉效果
暂未订购
上一页 1 2 111 下一页 到第
使用帮助 返回顶部