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The blocking effect of the sand fences quantified using wind tunnel simulations 被引量:6
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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
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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
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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
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Blocking Effects of Spleen Vaccine on Vertical Transmission of Classical Swine Fever Virus in Sows 被引量:1
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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
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The Blocking Effect of Phenolic Acid on N-Nitrosomorpholine Formation in vitro 被引量:2
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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
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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
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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
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Blocking Response Surface Designs Incorporating Neigh-bour Effects
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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
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Effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats
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作者 Zuoli Xia1, Baoliang Sun2, Mingfeng Yang1, Dongmei Hu2, Tong Zhao2, Jingzhong Niu2 1Institute of Brain Microcirculation, Taishan Medical College, Taian 271000, Shandong Province, China 2Department of Neurology, Affiliated Hospital of Taishan Medical College, Taian 271000, Shandong Province, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第7期657-660,共4页
BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel, it has lymphatic drain. Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introdu... BACKGROUND: It has been shown that although brain does not contain lining endothelial lymphatic vessel, it has lymphatic drain. Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system; however, the significance of lymphatic drain and the effect on cerebral edema remains unclear. OBJECTIVE: To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats. DESIGN: Randomized controlled animal study. SETTING: Institute of Cerebral Microcirculation of Taishan Medical College and Department of Neurology of Affiliated Hospital. MATERIALS: A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study. Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups: general observation group (n =12), light microscopic observation group (n =21) and electronic microscopic observation group (n =14). The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup. Sixteen rats were used for observing the effect of cerebral lymphatic block on cortical evoked potential, in which the animals were randomly divided into sham-operation group (n =6) and cerebral lymphatic block group (n =10). METHODS: The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003. Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition. Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels, respectively, and then lymph node was removed so as to establish cerebral lymphatic drain disorder models. Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes, and other operations were as the same as those in cerebral lymphatic block group. Morphological changes of the brain and alterations of latency of cortical evoked potential were detected on the 1st, 2nd, 3rd, 5th, 7th, 10th and 15th days after operation under general, light microscope and electronic microscope observations. MAIN OUTCOME MEASURES: ① Cerebral morphological changes; ② latent changes of cortical evoked potential. RESULTS: A total of 63 rats were involved in the final analysis. ① Cerebral morphological changes: General observation showed that, for cerebral lymphatic block rats, the surface of brain was pale and full, and cerebral gyrus was wide and flattened sulci after cerebral lymphatic block; and cerebral tissue space prolongation, increased interstitial fluid, neuronal degeneration and necrosis, diffused phagocytes and satellitosis were observed under light microscope. Neuronal swell and necrosis, glial cell swell, apparent subcellular changes such as mitochondron were observed under electronic microscope. ② Latent changes of cortical evoked potential: As compared with sham-operation control group, latency of cortical evoked potential in cerebral lymphatic blockage group prolonged on the 5th day and 7th day after cerebral lymphatic block [(6.28±0.23), (6.97±0.35) ms; (6.23±0.22), (7.12±0.20) ms; P < 0.01]. CONCLUSION: ① Cerebral lymphatic block plays an important role in cerebral morphology, and may result in abnormality of sensitive impulse conduction and prolong latency of cortical evoked potential. ② Examination of cortical evoked potential is easy and convenient, so it is regarded as a key index for lymphatic disturbed cerebral injury. 展开更多
关键词 effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats
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Effect of Mg-Preflow for p-AlGaN Electron Blocking Layer on the Electroluminescence of Green LEDs with V-Shaped Pits
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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
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Left- and Right-Handers May Unintentionally Apply Different Cognitive Strategies in Response to Situational Demands: Study Using the Block-Wise Proportion Congruency Effect
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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
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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
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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
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Mechanisms of shale hydration and water block removal 被引量:3
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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
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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
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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
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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
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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
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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
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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
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Effect of specifically-adsorbed polysulfides on the electron transfer kinetics of sodium metal anodes 被引量:1
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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
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Preparation of Polyacrylate-based Conductive Coatings and Its PTC Effect 被引量:3
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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
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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
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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
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CONSTRUCTION OF OPTIMAL BLOCKING SCHEMES FOR ROBUST PARAMETER DESIGNS 被引量:2
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作者 杨建峰 张润楚 刘民千 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1431-1438,共8页
Robust parameter design (RPD) is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the c... Robust parameter design (RPD) is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the correspondence relation between fractional factorial RPDs and the blocking schemes for full factorial RPDs. In addition, we provide a construction of optimal blocking schemes that make all main effects and control-by-noise two-factor interactions estimable. 展开更多
关键词 ALIAS blockING factorial design factorial effect robust parameter design
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Twin-block矫治安氏Ⅱ类错合畸形临床疗效观察 被引量:5
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作者 招惠珍 王新革 殷慧 《中国医药导报》 CAS 2012年第12期51-51,54,共2页
目的分析采用Twin-block矫治安氏Ⅱ类错合畸形的临床疗效。方法回顾性分析2007年5月~2010年6月在我院确诊的安氏Ⅱ类错颌畸形患者38例,对治疗前后的上下切牙位置、前牙覆盖情况、磨牙关系以及上下颌骨的变化进行对比分析。结果 Twin-bl... 目的分析采用Twin-block矫治安氏Ⅱ类错合畸形的临床疗效。方法回顾性分析2007年5月~2010年6月在我院确诊的安氏Ⅱ类错颌畸形患者38例,对治疗前后的上下切牙位置、前牙覆盖情况、磨牙关系以及上下颌骨的变化进行对比分析。结果 Twin-block矫治可以明显促进下颌骨发育,改善外观,治疗后上切牙平均后移2.8 mm,下切牙平均前移2.6 mm,前牙覆盖平均减少4.9 mm。结论Twin-block矫治安氏Ⅱ类错合畸形效果确切,不但可以有效地利用下颌骨向前生长的潜力,而且可以使下颌前移,以致下颌磨牙前移,改善Ⅱ类磨牙关系,同时可以使唇向上切牙舌向移动,进一步改善深覆盖状况,是一种安全有效的方法,值得临床大力推广。 展开更多
关键词 TWIN-block 安氏Ⅱ类错合畸形 临床疗效
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髋部骨折麻醉前应用股神经阻滞和舒芬太尼镇痛的效果对比 被引量:3
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作者 张丽 郝建红 +2 位作者 刘瑶 张亮 申新 《医学研究前沿》 2025年第1期37-39,共3页
目的探讨对比髋部骨折麻醉前应用股神经阻滞(FNB)和舒芬太尼镇痛的效果。方法将2023年1月至2024年5月在我院治疗的74例髋部骨折手术患者随机划分为两个组别,在麻醉诱导程序启动之前,对照组采纳舒芬太尼作为预处理手段,观察组则选用FNB... 目的探讨对比髋部骨折麻醉前应用股神经阻滞(FNB)和舒芬太尼镇痛的效果。方法将2023年1月至2024年5月在我院治疗的74例髋部骨折手术患者随机划分为两个组别,在麻醉诱导程序启动之前,对照组采纳舒芬太尼作为预处理手段,观察组则选用FNB。结果在T1-3的时间点,观察组MAP、HR均更稳定,保持较合理水平(P<0.05);观察组所需的瑞芬太尼与丙泊酚剂量较少,术后1h、3h、6h的VAS疼痛评分也低一些(P<0.05);观察组恶心呕吐、尿潴留、头晕、呼吸抑制等不良反应发生率低于对照组(P<0.05)。结论对于髋部骨折患者而言,麻醉诱导前采用FNB相较于舒芬太尼能更有效地减少麻醉药物用量,增强血流动力学稳定性,提升术后镇痛质量,减少不良反应。 展开更多
关键词 髋部骨折 麻醉 股神经阻滞 舒芬太尼 效果
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