期刊文献+
共找到778篇文章
< 1 2 39 >
每页显示 20 50 100
Effect of local blocking on osteoarthritis of the hip
1
作者 Dao-Bing Liu Rong-Tian Wang +5 位作者 Yan Li Yu Zhou Jun-Yu Wang Hai-Jun He Bin Xie Wei-Heng Chen 《Journal of Hainan Medical University》 2021年第2期33-37,共5页
Objective:To provide an effective treatment for the Osteoarthritis of the hip by observing the effect of local blocking of HongHua injection on relieving hip pain.Methods:Methods from June 2015 to May 2017,60 patients... Objective:To provide an effective treatment for the Osteoarthritis of the hip by observing the effect of local blocking of HongHua injection on relieving hip pain.Methods:Methods from June 2015 to May 2017,60 patients with Osteoarthritis of the hip in Wangjing Hospital of Chinese Academy of Sciences were randomly divided into treatment group and control group,30 cases in each group.The treatment group was given local blockingof HongHua injection treatment,control group using Compound Betamethasone Injection local closed treatment.Visual analogue scale(VAS)score,pericoxal local tenderness and hip mobility were used to evaluate the therapeutic effect.The therapeutic indicators at six different time points after 1 days,3 days,7 days,2 weeks and 1 months after treatment were compared.Results:All the 60 cases completed treatment and follow-up,and there were no cases of abscission.There was no significant difference in gender,age,etiology,classification and Harris score before treatment between the two groups(P>0.05),which was comparable.VAS score:There was no significant difference between the two groups on the 1st,3rd,7th and 2nd week after treatment(P>0.05),but the treatment group was lower than the control group on the 1st month after treatment(P<0.01).Hip joint activity:There was no significant difference in hip joint activity between the two groups 1 day,3 days,7 days,2 weeks and 1 month after treatment(P>0.05).Local tenderness around hip:The efficacy of the midpoint inguinal tenderness score was similar between the two groups at 1 day,7 days,2 weeks and 1 month after treatment(P>0.05);the treatment group was lower than the control group at 3 days after treatment(P<0.01);the adductor starting tenderness score had no significant difference at 1 day,3 days,7 days,2 weeks and 1 month after treatment(P>0.05).Conclusion:Local blockingof HongHua injection is effective and effective in treating hip pain in Osteoarthritis of the hip.The HongHua injection has many advantages,such as good safety and wide indications.It is worthy of further clinical application. 展开更多
关键词 Osteoarthritis of the hip Pain around hip local blocking HongHua injection Clinical Research
下载PDF
Classification of Gastric Lesions Using Gabor Block Local Binary Patterns
2
作者 Muhammad Tahir Farhan Riaz +1 位作者 Imran Usman Mohamed Ibrahim Habib 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期4007-4022,共16页
The identification of cancer tissues in Gastroenterology imaging poses novel challenges to the computer vision community in designing generic decision support systems.This generic nature demands the image descriptors ... The identification of cancer tissues in Gastroenterology imaging poses novel challenges to the computer vision community in designing generic decision support systems.This generic nature demands the image descriptors to be invariant to illumination gradients,scaling,homogeneous illumination,and rotation.In this article,we devise a novel feature extraction methodology,which explores the effectiveness of Gabor filters coupled with Block Local Binary Patterns in designing such descriptors.We effectively exploit the illumination invariance properties of Block Local Binary Patterns and the inherent capability of convolutional neural networks to construct novel rotation,scale and illumination invariant features.The invariance characteristics of the proposed Gabor Block Local Binary Patterns(GBLBP)are demonstrated using a publicly available texture dataset.We use the proposed feature extraction methodology to extract texture features from Chromoendoscopy(CH)images for the classification of cancer lesions.The proposed feature set is later used in conjuncture with convolutional neural networks to classify the CH images.The proposed convolutional neural network is a shallow network comprising of fewer parameters in contrast to other state-of-the-art networks exhibiting millions of parameters required for effective training.The obtained results reveal that the proposed GBLBP performs favorably to several other state-of-the-art methods including both hand crafted and convolutional neural networks-based features. 展开更多
关键词 Texture analysis Gabor filters gastroenterology imaging convolutional neural networks block local binary patterns
下载PDF
Features and Principles the Spread of Local Anesthetic Blockade of the Sciatic Nerve at Depends on the Amount of Anesthetic 被引量:2
3
作者 Piacherski Valery Marachkou Aliaksei 《Open Journal of Anesthesiology》 2014年第2期31-35,共5页
Aim: To study the features of local anesthetic solution spreading during sciatic nerve block in dependence on the anesthetic solution volume. Material and Methods: One hundred and sixty nine cases of sciatic nerve blo... Aim: To study the features of local anesthetic solution spreading during sciatic nerve block in dependence on the anesthetic solution volume. Material and Methods: One hundred and sixty nine cases of sciatic nerve blocks done under ultrasonic visualization control were analyzed. Sciatic nerve blocks were performed by lidocaine in volumes 30;25;20;15;12.5;10;7.5;6.5;5;4.5 ml. The cross-section area, equal to local anesthetic spreading, was determined;the extension of the anesthetic solution spreading along sciatic nerve was calculated. Results: The anesthetic agent solution spreads along sciatic nerve in proximal and distal direction, forming a kind of cylinder. The minimum volume of the local anesthetic, which covers sciatic nerve in the whole, is 5 ml. A rare (1.77%) variation of sciatic nerve structure was described, in which tibial and common peroneal nerves develop directly from the branches of sacral plexus. Conclusion: The decrease of the local anesthetic volume leads to reduction of its spreading distance and cross-section area. Ultrasonic visualization can provide for sciatic nerve anatomical peculiarities, which can have an effect on the block quality. 展开更多
关键词 SCIATIC NERVE block ULTRASOUND-GUIDED local ANESTHETIC Spreading
下载PDF
Different Volumes of Local Anesthetics in Ultrasound-Guided Combined Interscalene-Supraclavicular Block for Traumatic Humeral Fracture 被引量:2
4
作者 Mohamed Mohamed Abdelhaq Ahmed Mostafa Kamal Mohamed Adly Elramely 《Open Journal of Anesthesiology》 2016年第4期55-62,共8页
Background: Procedures that require anesthesia of entire length of the arm should have combined Interscalene block (ISB) and Supraclavicular block (SCB) to ensure adequate block. However, dual block requires high dose... Background: Procedures that require anesthesia of entire length of the arm should have combined Interscalene block (ISB) and Supraclavicular block (SCB) to ensure adequate block. However, dual block requires high dose of local anesthetic (LA). We examined if Ultrasound (U/S) guided block helps to decrease the required volume of LA by visualizing trunks, so we only need injection of LA toward cervical nerve roots C5 and C6 aiming to block branches escaped from supraclavicular block. Patients and methods: Ninety-three patients were randomly allocated into one of three equal groups, each included 31 patients. All patients received SCB 20 ml (10 ml Bupivacaine 0.5% plus 10 ml lidocaine 2%) and ISB with different volumes of LA according to the group as follow: group A: 20 ml, group B: 15 ml, and group C: 10 ml. Result: No significant difference in onset of block (sensory and motor) and duration of block (motor only) between the three groups (P value > 0.05). The duration of sensory block was significantly longer in group A (760.65 ± 30.87 minutes) than in either group B (740.48 ± 21.15 minutes, P value P value P value P value P value P value < 0.001). Conclusion: A reduced volume of LA can be used in ultra sound guided ISB in combined with SCB to give satisfactory level of anesthesia to entire length of the arm, but the sensory block duration and duration of post-operative analgesia will be decreased significantly with decreasing the volume. 展开更多
关键词 Interscalene block Supraclavicular block Volume of local Anesthetic Ultrasound
下载PDF
Effects of Repeated Injection of Local Anesthetic on Sciatic Nerve Blocks Response
5
作者 王忱 刘怀萍 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第5期497-499,共3页
In order to examine whether repeated sciatic nerve blocks showed tachyphylaxis and continuity of sciatic nerve with spinal cord affected development of tachyphylaxis when assayed in vivo by duration of depression comp... In order to examine whether repeated sciatic nerve blocks showed tachyphylaxis and continuity of sciatic nerve with spinal cord affected development of tachyphylaxis when assayed in vivo by duration of depression compound action potentials (CAP), rats were anesthetized with halothane, ventilated, monitored and supported with stable hemodynamics and temperature. Posterior tibial nerve distally and sciatic nerve in thigh were exposed, placed on bipolar silver electrodes for stimulation and recording respectively. Three sequential sciatic nerve blocks were performed between these electrodes using 0.15 ml of 3 % chloroprocaine. Nine rats were chosen to observe the effects of repeated sciatic nerve blocks on CAP. In another 18 rats, a second investigator exposed the sciatic nerve near its origin at spinal cord and randomly performed nerve cut and sham (n=9), and closed the incision blinding the electrophysiologic investigator. The results showed that electrical stimulated tibial nerve induced sciatic nerve Aα/β, Aδ, C fiber mediated CAP waves. CAP amplitudes were remained stable during whole experimental procedure. CAP amplitudes were decreased completely with 3% chloroprocaine blocked sciatic nerve and recovered fully. The duration of CAP depression were reduced with repeated blocks. There were no selective blocked effects on Aα/β, Aδ, C fiber mediated CAP. With sciatic nerve cut proximally, there was no statistical significant tachyphylaxis with 3 % chloroprocaine repeated blocked sciatic nerve, and the duration of first and third blocked Aδ fiber mediated CAP was 108±20 and 92±14 min respectively (P>0.05). In normal rats the duration of first and third blocked Aδ fiber mediated CAP was 110±20 and 75±16 min respectively (P<0.05). It was suggested that tachyphylaxis to local anesthetics can occur in rats repeated blocked sciatic nerve when assayed in vivo by duration of depression CAP. The continuity of sciatic nerve with spinal cord is one of the important factors affecting the development of tachyphylaxis. 展开更多
关键词 local anesthetic TACHYPHYLAXIS CHLOROPROCAINE nerve block
下载PDF
Outcome Values of Adding Sodium Bicarbonate, Dexamethasone and Fentanyl to Local Anesthetic in Peribulbar Block during Vitreoretinal Surgeries. A Randomized Prospective Study
6
作者 Sherif Kamal Arafa Amir Abouzkry El-Sayed 《Open Journal of Anesthesiology》 2018年第1期1-13,共13页
Background and aims: we aimed to detect the outcome values of adding fentanyl, dexamethasone and sodium bicarbonate to mixture of local anesthetic in peribulbar block for vitreoretinal surgery. Methods: 120 adult ASA ... Background and aims: we aimed to detect the outcome values of adding fentanyl, dexamethasone and sodium bicarbonate to mixture of local anesthetic in peribulbar block for vitreoretinal surgery. Methods: 120 adult ASA I & II patients, admitted for vitreoretinal surgery under peribulbar block were included in this comparative study. This study included 4 groups: Group I: (30) patients using a mixture of 1 ml normal saline, 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. Group II: (30) patients using a mixture of 1 ml of sodium bicarbonate (from 1 ml sodium bicarbonate 8.4% diluted in 10 ml normal saline), 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. Group III: (30) patients using a mixture of 1 ml fentanyl 20 μg (from a mixture of fentanyl 100 μg diluted in 5 ml normal saline), 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. Group IV: (30) patients using a mixture of 1 ml of 4 mg dexamethasone (1 ampoule = 8 mg/2 ml), 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. We measured the onset and duration of anesthesia, IOP, eyelid and global akinesia, postoperative pain by numerical pain rating scale, first analgesic requirement and postoperative side effects. Results: No significant differences were detected among the four groups as respect to age, sex and the intraocular pressure (IOP) before the anesthesia block. While the intraocular pressure (IOP) after the anesthesia block there was a significant difference, as IOP was markedly decreased postoperatively in group II compared with other groups. As regard to the onset & duration of anesthesia there was significant difference among all groups, there was rapid onset and prolonged duration of anesthesia in group III compared with other groups (1.77 ± 0.63 & 5.03 ± 0.89) respectively. As regard the onset of lid akinesia there was significant difference among the four groups with better outcome in group III, as in group III represented the most rapid onset of lid akinesia. As respecting to the onset of global akinesia there was significant difference among the four groups. There was better outcome in group III as it represented more rapid onset of global akinesia compared with other groups. There were significant differences among the four groups as regard postoperative pain all over 6 hours, better results were in group III (0.27 ± 0.69) compared with group I (2.23 ± 1.17), group II (2.00 ± 1.70), group IV (0.67 ± 0.71). As regarding to the first time for analgesic requirement there were significant differences among groups, there was no request for analgesia with better outcome in group III with increasing need to the analgesic medication in group I compared to group II and group IV. As regard side effects postoperatively there were few side effects in all groups with few numbers of cases in groups III only one patient. Although these differences in number of patients are not significant among the four groups. Conclusion: Addition of sodium bicarbonate to local anesthetic mixture was the best way in lowering the IOP other than other groups and addition of fentanyl to local anesthesia provided more rapid onset and duration of anesthesia, more rapid onset and duration for lid and global akinesia, less pain, less analgesic requirement and minimal side effects than the other groups. 展开更多
关键词 FENTANYL DEXAMETHASONE Sodium BICARBONATE local ANESTHESIA Peribulbar block Vitreoretinal Surgeries
下载PDF
一类Block型李代数的2-局部导子
7
作者 肖明月 唐孝敏 《东北师大学报(自然科学版)》 CAS 北大核心 2023年第4期9-13,共5页
对一类Block型李代数的2-局部导子进行研究,证明了这类Block型李代数的2-局部导子都是导子.
关键词 block型李代数 导子 2-局部导子
下载PDF
以神经阻滞专题为导向的硕士研究生局部解剖学教学设计
8
作者 张波 梁亮 +4 位作者 王峰 朱友余 庞刚 任振华 邓雪飞 《中国卫生产业》 2024年第6期32-36,共5页
局部解剖学在外科硕士研究生的培养中占据着核心位置,尤其是对于神经阻滞等精细操作技能的学习。本研究团队通过对传统教学模式的创新,开发了“以神经阻滞专题为导向”的教学设计,旨在提升研究生在局部解剖学及其在临床实践中应用的理... 局部解剖学在外科硕士研究生的培养中占据着核心位置,尤其是对于神经阻滞等精细操作技能的学习。本研究团队通过对传统教学模式的创新,开发了“以神经阻滞专题为导向”的教学设计,旨在提升研究生在局部解剖学及其在临床实践中应用的理解和技能。本文详细介绍了该教学设计的原则、思路、内容和方法,通过多元化教学策略,提升学生的学习动力和实践技能。尽管面临资源、团队构建和学习动力不一致等方面的挑战,本教学设计在提高教学效果和培养具有高尚医德、丰富知识和精湛技能的医学人才方面展现出显著潜力,对医学教育的发展和创新具有重要的参考价值。 展开更多
关键词 神经阻滞 局部解剖学 研究生培养 教学设计
下载PDF
不同局麻药佐剂在周围神经阻滞中的应用进展
9
作者 谢淑华 牛敏 耿立成 《中国伤残医学》 2024年第13期151-155,160,共6页
超声引导下周围神经阻滞技术在临床麻醉和术后镇痛中的应用越来越广泛。目前,怎样缩短周围神经阻滞的起效时间、延长所用局麻药的作用时间、降低局麻药的毒性反应、增强周围神经阻滞效果是临床麻醉关注的热点问题。许多学者为了缩短周... 超声引导下周围神经阻滞技术在临床麻醉和术后镇痛中的应用越来越广泛。目前,怎样缩短周围神经阻滞的起效时间、延长所用局麻药的作用时间、降低局麻药的毒性反应、增强周围神经阻滞效果是临床麻醉关注的热点问题。许多学者为了缩短周围神经阻滞麻醉的起效时间,增强阻滞效果,延长阻滞的作用时间,尝试了在局麻药中加入多种佐剂进行研究,对比了在周围神经阻滞中应用不同局麻药佐剂的作用效果。本文将对近年来在周围神经阻滞中应用不同局麻药佐剂的应用和研究进展做一综述,以期为临床麻醉医生进行周围神经阻滞提供指导。 展开更多
关键词 周围神经阻滞 局麻药 佐剂
下载PDF
面向超分辨率重建的层次间局部特征增强网络
10
作者 王晓峰 黄煜婷 +2 位作者 张文尉 张轩 陈东方 《计算机工程与设计》 北大核心 2024年第8期2407-2414,共8页
基于卷积神经网络的超分辨率重建模型以单项传播为主,层次越靠后感知信息的能力越微弱,导致层次间局部特征部分丢失,难以实质提升网络的特征表达能力。针对此问题,提出层次间局部特征增强网络。该方法由级联残差模块、层次间特征增强块... 基于卷积神经网络的超分辨率重建模型以单项传播为主,层次越靠后感知信息的能力越微弱,导致层次间局部特征部分丢失,难以实质提升网络的特征表达能力。针对此问题,提出层次间局部特征增强网络。该方法由级联残差模块、层次间特征增强块和特征感知注意力机制组成。级联残差模块通过有效残差连接增加对残差分支信息的利用;层次间特征增强块提取不同深度特征的依赖关系,自适应调整中间层特征权值增强捕获关键信息的能力;特征感知注意力机制采用方向感知和位置判断的方式准确定位和识别感兴趣对象。多项标准数据集的实验结果表明,该方法能改善超分辨率的视觉重建效果,整体性能优于现有方法。 展开更多
关键词 卷积神经网络 超分辨率 局部特征增强 级联残差模块 注意力机制 方向感知 位置判断
下载PDF
IPACK阻滞与LIA在膝关节矫形术的应用效果比较
11
作者 董星 李欣 赵克非 《黑龙江医学》 2024年第9期1061-1063,共3页
目的:比较腘动脉与膝关节后囊间隙(IPACK)阻滞与关节周围局部浸润镇痛(LIA)在膝关节矫形术后镇痛中的效果。方法:招募60例膝关节矫形术患者,随机分为IPACK阻滞组(I组)和LIA组(L组)。I组行IPACK阻滞,L组行LIA。记录疼痛评分、满意度评分... 目的:比较腘动脉与膝关节后囊间隙(IPACK)阻滞与关节周围局部浸润镇痛(LIA)在膝关节矫形术后镇痛中的效果。方法:招募60例膝关节矫形术患者,随机分为IPACK阻滞组(I组)和LIA组(L组)。I组行IPACK阻滞,L组行LIA。记录疼痛评分、满意度评分、主动屈膝最大角度、步行距离、镇痛补救率和不良事件发生情况。结果:与L组比较,8h(T2)时点I组静态疼痛评分降低,差异有统计学意义(Z=-2.171,P<0.05);与L组比较,T2,24h(T3)时点I组动态疼痛评分降低,差异有统计学意义(Z=-1.277、-2.841,P<0.05);与L组比较,I组羟考酮应用率降低,差异有统计学意义(χ^(2)=6.667,P<0.05);与L组比较,I组术后2~3d患者主动屈膝最大角度增加,差异有统计学意义(Z=-2.088、-2.426,P<0.05)。结论:IPACK阻滞较LIA更适合于膝关节矫形术后镇痛。 展开更多
关键词 腘动脉与膝关节后囊间隙阻滞 关节周围局部浸润镇痛 膝关节矫形术
下载PDF
基于HRNet的高分辨率遥感影像道路提取方法 被引量:3
12
作者 陈雪梅 刘志恒 +2 位作者 周绥平 余航 刘彦明 《系统工程与电子技术》 EI CSCD 北大核心 2024年第4期1167-1173,共7页
高分辨率遥感影像中,传统的道路提取方法存在着精度低、鲁棒性低的问题,提出基于高分辨率网络(high-resolution net, HRNet)实现高分辨率遥感影像道路分割。对HRNet进行改进,将相同分辨率的HRNet子网的输出与输出层结果进行拼接并输入... 高分辨率遥感影像中,传统的道路提取方法存在着精度低、鲁棒性低的问题,提出基于高分辨率网络(high-resolution net, HRNet)实现高分辨率遥感影像道路分割。对HRNet进行改进,将相同分辨率的HRNet子网的输出与输出层结果进行拼接并输入非局部块,两个损失函数Cross-entropy Loss和Dice Loss用来解决道路数据集样本不平衡问题。实验结果表明,改进的HRNet在公开的CHN6-CUG道路数据集上的分割性能与其他方法相比对道路的提取效果更好,在召回率、均交并比和F1分数3个方面分别达到了97.65%、84.91%和97.25%。 展开更多
关键词 高分辨率网络 非局部块 遥感影像 深度学习
下载PDF
结合血管拓扑和Non-local CNN-GCN的肺动静脉分离方法 被引量:3
13
作者 黄立勤 陈柳清 +2 位作者 潘林 郑斌 郑绍华 《福州大学学报(自然科学版)》 CAS 北大核心 2022年第1期24-30,共7页
为解决肺CT影像中动、静脉血管的自动分离、精确提取问题,提出一种结合血管拓扑与连接非局部卷积神经网络和图卷积网络(Non-local CNN-GCN)的肺动静脉自动分离方法.首先,使用尺度空间粒子采样方法将血管树表示为一组中心线体素粒子;然后... 为解决肺CT影像中动、静脉血管的自动分离、精确提取问题,提出一种结合血管拓扑与连接非局部卷积神经网络和图卷积网络(Non-local CNN-GCN)的肺动静脉自动分离方法.首先,使用尺度空间粒子采样方法将血管树表示为一组中心线体素粒子;然后,根据粒子体素及其相邻体素构造拓扑图,并从拓扑图中提取只包含动脉或静脉分支的拓扑子图;最后,基于拓扑图训练Non-local CNN-GCN分类器,并利用拓扑子图来改进分类结果.在16例CT影像数据上进行训练和测试,结果显示,本方法能有效去除动静脉黏连点,分类平均准确度达94%. 展开更多
关键词 动静脉分离 深度学习 非局部模块 CNN-GCN网络
下载PDF
地方视角下苏州古城滨水街区节点活力营造策略——以山塘历史文化街区为例 被引量:1
14
作者 李蕊彤 毛政烨 +2 位作者 王瀚坤 俞喆涵 张芳 《城市建筑》 2024年第5期1-5,44,共6页
江南城市水网纵横,水资源孕育了极具地方特色的滨水街区。随着城市建设发展,河道不再承载其原本的功能,街区滨水空间逐渐衰败。历史文化街区的地域特色及其在现代社会发展中如何平衡,关系到文化与历史记忆的传承。文章从“地方性”视角... 江南城市水网纵横,水资源孕育了极具地方特色的滨水街区。随着城市建设发展,河道不再承载其原本的功能,街区滨水空间逐渐衰败。历史文化街区的地域特色及其在现代社会发展中如何平衡,关系到文化与历史记忆的传承。文章从“地方性”视角切入,对街区滨水空间节点进行分类研究,为节点活力营造提出具体策略。 展开更多
关键词 传统滨水街区 地方性 活力营造 节点改造 古城更新 山塘街
下载PDF
选择性神经阻滞在自体动静脉内瘘成形术中的应用及对内瘘成熟的影响
15
作者 温静 王玉柱 詹申 《肾脏病与透析肾移植杂志》 CAS CSCD 2024年第3期226-232,共7页
目的:评估选择性神经阻滞在自体动静脉内瘘(AVF)成形术中的有效性及对术后内瘘成熟率的影响。方法:本研究为回顾性队列研究,选取2022-01-01~2022-12-31在北京大学第三医院海淀院区行AVF成形术的患者,根据术前麻醉类型分为选择性神经阻滞... 目的:评估选择性神经阻滞在自体动静脉内瘘(AVF)成形术中的有效性及对术后内瘘成熟率的影响。方法:本研究为回顾性队列研究,选取2022-01-01~2022-12-31在北京大学第三医院海淀院区行AVF成形术的患者,根据术前麻醉类型分为选择性神经阻滞组(S组)和局部浸润麻醉组(L组)。采用视觉模拟评分法(VAS)比较两组患者术中的疼痛程度,术后即刻、4周、8周、12周的吻合血管内径及肱动脉血流量,并比较两组的内瘘成熟率。结果:共纳入207例患者,S组44例(21.26%),L组163例(78.74%)。与L组相比,S组患者术前吻合血管内径更细(P<0.05),术中VAS更低(Z=-2.598,P=0.009),麻醉后5 min的吻合静脉内径、术后即刻肱动脉血流量更大(P<0.05)。S组患者术后内瘘头静脉内径及肱动脉血流量明显高于L组(均P<0.05),4周和8周时S组的成熟率明显高于L组(P均<0.05),12周时两组成熟率差异无统计学意义(χ^(2)=1.616,P=0.204)。结论:选择性神经阻滞用于AVF成形术时,可安全有效镇痛,兼具扩张血管、增加术后内瘘血流量及提高短期内瘘成熟率的优势,尤其适合于血管较细的患者。 展开更多
关键词 自体动静脉内瘘 血液透析 麻醉 选择性神经阻滞 局部浸润麻醉
下载PDF
联合多尺度块匹配的非局部均值去噪算法
16
作者 陈浩宇 许光宇 《海南师范大学学报(自然科学版)》 CAS 2024年第1期46-55,共10页
针对非局部均值(Non-Local Means,NLM)图像去噪算法易产生伪影与平滑细节的问题,提出一种联合多尺度图像块匹配的像素相似性测度,提高NLM算法去噪性能。首先,研究与分析了加权欧氏距离与欧氏距离两种相似性度量以及图像块尺寸设置对NLM... 针对非局部均值(Non-Local Means,NLM)图像去噪算法易产生伪影与平滑细节的问题,提出一种联合多尺度图像块匹配的像素相似性测度,提高NLM算法去噪性能。首先,研究与分析了加权欧氏距离与欧氏距离两种相似性度量以及图像块尺寸设置对NLM算法的影响。其次,通过引入图像特征信息并利用K-means聚类方法将图像划分为平坦区域和包含边缘与纹理的结构区域,对每个类别中的像素点,联合两种尺度图像块匹配计算像素的平滑权重。最后,优化了算法的滤波参数。实验结果表明,提出的算法在噪声去除与细节保持方面明显优于经典的NLM算法,相比其他改进的NLM算法也有优势。 展开更多
关键词 图像去噪 非局部均值 局部特征 多尺度块匹配
下载PDF
融合注意力谱非局部块的视网膜图像质量分级
17
作者 梁礼明 董信 +2 位作者 雷坤 夏雨辰 吴健 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2024年第4期102-113,共12页
视网膜图像质量评估(RIQA)是筛查糖尿病视网膜病变的关键组成部分之一。针对视网膜图像质量差异大且质量评估模型泛化能力不足等问题,提出一种融合注意力谱非局部块的多特征算法来对RIQA进行预测分级。首先采用融合光谱非局部块的ResNe... 视网膜图像质量评估(RIQA)是筛查糖尿病视网膜病变的关键组成部分之一。针对视网膜图像质量差异大且质量评估模型泛化能力不足等问题,提出一种融合注意力谱非局部块的多特征算法来对RIQA进行预测分级。首先采用融合光谱非局部块的ResNet50网络对输入图像进行特征提取;其次引入高效通道注意力用于提升模型对数据的表达能力,有效捕获通道间特征信息关系;再次利用特征迭代注意力融合模块对各局部特征信息融合;最后联合焦点损失和正则损失进一步提高质量分级的效果。在Eye-Quality数据集上准确率为88.59%,精确度为87.56%,敏感度和F1值分别为86.10%和86.74%。在RIQA-RFMiD数据集上准确率和F1值分别为84.22%和67.17%,仿真实验表明,文中算法对视网膜图像质量评估任务中具有较好的泛化能力。 展开更多
关键词 视网膜图像质量分级 谱非局部块 注意力机制 特征迭代融合 组合损失
下载PDF
A型肉毒毒素、乙醇肌内局部注射联合局部封闭治疗痉挛性斜颈14例
18
作者 陈明长 高伟明 胡文彬 《安徽医药》 CAS 2024年第5期992-998,共7页
目的分析颈项部肌内局部注射A型肉毒毒素(BTX-A)、肌内乙醇阻滞(MAB)和局部封闭联合方案治疗痉挛性斜颈的临床特点、疗效、预后以及长期随访。方法回顾性分析2004年5月至2021年10月在安徽中医药大学神经病学研究所附属医院就诊,明确诊... 目的分析颈项部肌内局部注射A型肉毒毒素(BTX-A)、肌内乙醇阻滞(MAB)和局部封闭联合方案治疗痉挛性斜颈的临床特点、疗效、预后以及长期随访。方法回顾性分析2004年5月至2021年10月在安徽中医药大学神经病学研究所附属医院就诊,明确诊断为痉挛性斜颈并采用BTX-A、MAB以及封闭疗法联合治疗的病人的临床资料,在治疗前后行Tsui量表、全面肌张力障碍量表(FMRS)评估疗效,出院后进行长期随访调查和36项简明健康问卷调查(SF-36)。按随访结果将病人分为症状复发组和症状未复发组,比较各临床因素同临床结果之间的关系。结果14例病人中,男性4例,女性10例,年龄范围为18~47岁。Tsui量表治疗前为(11.86±4.37)分,治疗后为(1.07±0.92)分,治疗后评分显著降低(P<0.01);Tsui量表提示13例病人症状为完全缓解,1例为明显缓解。FMRS治疗前为(8.21±3.62)分;治疗后为(0.89±0.86)分,治疗后评分显著降低(P<0.01)。随访结果表明14例病人中4例长期随访至今未曾复发;6例复发,疗效维持时间均>14个月;4例随访丢失。病人出院半年后进行SF-36健康状况问卷调查,显示随访到的10例病人9项得分均>80.3分,提示生命质量较高,预后较好。按随访结果分组,两组年龄、性别、病程、身体质量指数(BMI)、临床分型、BTX-A剂量、BTX-A注射次数、封闭次数比较,差异无统计学意义(P>0.05);两组治疗前Tsui评分、MAB注射次数比较,差异有统计学意义(P<0.05)。结论BTX-A、MAB联合局部封闭疗法治疗痉挛性斜颈病人疗效显著,维持时间较长,未见明显并发症,值得临床上进一步扩大样本量进行对比分析等系列研究与推广应用。 展开更多
关键词 斜颈 A型肉毒毒素 肌内乙醇阻滞 局部封闭 疗效
下载PDF
基于BM3D的脑MRI图像噪点剔除算法
19
作者 徐梦笔 何刚 《计算机技术与发展》 2024年第9期70-76,共7页
磁共振成像(Magnetic Resonance Imaging,MRI)已经成为一种常见的影像检查方式,MRI的去噪算法影响着MRI的成像效果。基于深度学习的MRI去噪算法需要一定量的数据,绝大部分基于非深度学习的MRI去噪算法都是将MRI数据转化为实数之后进行... 磁共振成像(Magnetic Resonance Imaging,MRI)已经成为一种常见的影像检查方式,MRI的去噪算法影响着MRI的成像效果。基于深度学习的MRI去噪算法需要一定量的数据,绝大部分基于非深度学习的MRI去噪算法都是将MRI数据转化为实数之后进行去噪的,针对复数MRI中的复数数据类型的算法也存在着失真的问题。因此,提出一种通过单张MRI脑图像的原始数据进行噪点剔除的算法,以此更好得去除图像噪声。该算法从MRI的原始数据出发,利用了MRI噪声分布性质和MRI脑图像的特点,以判断MRI图像中噪声明显的点,从而剔除MRI中特定的莱斯分布的噪声。并将所提出的算法结合了MRI去噪中常用的非局部平均算法(Non-Local Means denoising,NLM)与三维块匹配算法(Block-Matching and 3D filtering,BM3D),并和不使用该算法剔除噪点的NLM、BM3D进行了对比评估。对比结果表明,在噪声密度不同的多种情况下,该算法总能优化与之相结合的图像去噪算法,在不同的噪声情况下使峰值信噪比(Peak Signal-to-Noise Ratio,PSNR)与结构相似性(Structural Similarity,SSIM)提高了1%~9%。最后将该算法结合BM3D,对比了DnCNN、低秩聚类算法(Weighted Nuclear Norm Minimization,WNNM)、BM3D、NLM等用于MRI去噪的算法,在莱斯噪声较多时,该算法在PSNR上有更好的表现。 展开更多
关键词 脑磁共振成像 噪声去除 莱斯分布 非局部平均算法 三维块匹配算法
下载PDF
一种局域共振型声学超材料的半解析建模与带隙机制研究
20
作者 赵振成 张涵柯 郑玲 《振动与冲击》 EI CSCD 北大核心 2024年第3期27-36,45,共11页
基于声学黑洞(acoustic black hole, ABH)弧形梁体积小且模态频率丰富的特点,将声学黑洞弧形梁作为附加结构周期分布在直梁上,达到促进局域共振效应和拓宽低频带隙的作用,由此构建一种新的局域共振型声学超材料。针对局域共振型超材料,... 基于声学黑洞(acoustic black hole, ABH)弧形梁体积小且模态频率丰富的特点,将声学黑洞弧形梁作为附加结构周期分布在直梁上,达到促进局域共振效应和拓宽低频带隙的作用,由此构建一种新的局域共振型声学超材料。针对局域共振型超材料,采用高斯展开法,建立其半解析理论分析模型,基于零空间法处理其内部连接以及周期边界条件,并通过有限元法验证半解析理论分析模型的准确性。分析和计算其能带结构,研究结构参数以及ABH效应对布拉格带隙以及局域共振带隙的影响机理。研究结果表明,该半解析理论模型能够对结构的带隙进行有效计算,附加弧形ABH的陷波机制能够促进结构的局域共振效应并对主梁进行有效减振,为声学黑洞声学超材料的应用提供了新的思路。 展开更多
关键词 声学黑洞(ABH) 局域共振 声学超材料 低频带隙
下载PDF
上一页 1 2 39 下一页 到第
使用帮助 返回顶部