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Modeling and Analysis of Transitional Tube with Constant Sectional Area along Derivative Central Route 被引量:1
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作者 MENG Xiang-bao TONG Bao-guo +1 位作者 PAN Zi-jian LI Hai-xing 《Computer Aided Drafting,Design and Manufacturing》 2011年第2期19-24,共6页
Firstly, sample square-circular transition tube along straight central route was modeled on CATIA software. The parameters are as follows: let the tube length is L, and the constant cross section area is S, and S = ... Firstly, sample square-circular transition tube along straight central route was modeled on CATIA software. The parameters are as follows: let the tube length is L, and the constant cross section area is S, and S = πR^2 = a2, in which R stands for the circle radius on one end, and a the square side length on the other end; set up the coordinate system with OX axis on the central route in which the origin O is on centroid of the square end and assume the cross section size at x as the square shaped with all four comers filleted in radius r which is proportional to x, that is, the linear slope of r is R/L, thus, both values r and square side length ax can be attained on the constant cross section area assumption. Secondly, some sample polygonal-circular transition tubes along straight, circular and helical central route were implemented similarly. Thirdly, numerical analysis of stress and displacement of these tubes were carried out on MSC/PATRAN software which are important to the distribution of turbulent flow and the layout of these transitional tube structures. 展开更多
关键词 parametric modeling transitional tube constant cross section area finite element analysis CATIA application
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Cause of over Water Quality Standard and Control Measures of State-controlled Sections in Northern Water-deficient Area of Jiangsu 被引量:5
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作者 胡永定 韩宝平 +1 位作者 钱新 袁兴程 《Meteorological and Environmental Research》 CAS 2010年第2期91-94,99,共5页
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r... Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology. 展开更多
关键词 State-controlled sections Cause analysis Control measures Water-deficient area China
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Relationship between sonographically measured median nerve cross-sectional area and presence of peripheral neuropathy in diabetic subjects 被引量:8
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作者 Fredrick ANDrew Attah Christianah Mopelola Asaleye +3 位作者 Adeleye Dorcas Omisore Babatope Ayodeji Kolawole Adeniyi Sunday Aderibigbe Mathew Alo 《World Journal of Diabetes》 SCIE CAS 2019年第1期47-56,共10页
BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerve... BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerves. Median nerve is one of the peripheral nerves commonly affected in diabetic neuropathy. The median nerve size has been studied in non-Nigerian diabetic populations. In attempt to contribute to existing literature, a study in a Nigerian population is needed.AIM To evaluate the cross-sectional area(CSA) of the median nerve using B-mode ultrasonography(USS) and the presence of peripheral neuropathy(PN) in a cohort of adult diabetic Nigerians.METHODS Demographic and anthropometric data of 85 adult diabetes mellitus(DM) and 85 age-and sex-matched apparently healthy control(HC) subjects were taken. A complete physical examination was performed on all study subjects to determine the presence of PN and modified Michigan Neuropathy Screening Instrument(MNSI) was used to grade its severity. Venous blood was taken from the study subjects for fasting lipid profile(FLP), fasting blood glucose(FBG) and glycated haemoglobin(HbA1 c) while their MN CSA was evaluated at a point 5 cm proximal to(5 cmCATL) and at the carpal tunnel(CATL) by high-resolution Bmode USS. Data was analysed using SPSS version 22.RESULTS The mean MN CSA was significantly thicker in DM subjects compared to the HC at 5 cmCATL(P < 0.01) and at the CATL(P < 0.01) on both sides. The presence of diabetic peripheral neuropathy(DPN) further increased the MN CSA at the CATL(P < 0.05) but not at 5 cmCATL(P > 0.05). However, the severity of DPN had no additional effect on MN CSA 5 cm proximal to and at the CATL. There was no significant association between MN CSA and duration of DM and glycemic control.CONCLUSION Thickening of the MN CSA at 5 cmCATL and CATL is seen in DM. Presence of DPN is associated with worse thickening of the MN CSA at the CATL but not at5 cmCATL. Severity of DPN, duration of DM, and glycemic control had no additional effect on the MN CSA. 展开更多
关键词 MEDIAN nerve CROSS-sectionAL area SONOGRAPHY DIABETICS Peripheral NEUROPATHY
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Method of Fault Area & Section Location for Non-solidly Earthed Distribution System 被引量:27
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作者 ZHENG Guping JIANG Chao LI Gang QI Zheng YANG Yihan 《中国电机工程学报》 EI CSCD 北大核心 2012年第13期I0014-I0014,197,共1页
中国中压配电网以架空线为主,多为小电流系统,单相接地故障占到电网故障总数的80%以上,但中国配网自动化系统基本上没有小电流接地故障定位功能,使配网自动化系统在提高可靠性的作用上大打折扣。给出一种小电流接地故障区段定位新... 中国中压配电网以架空线为主,多为小电流系统,单相接地故障占到电网故障总数的80%以上,但中国配网自动化系统基本上没有小电流接地故障定位功能,使配网自动化系统在提高可靠性的作用上大打折扣。给出一种小电流接地故障区段定位新方法,在线路上配置广域相量测量固定测点,获取小电流电网单相接地故障特征信息。基于测点相邻矩阵区段起始测点标识向量和故障路径标识向量概念,提出确定故障区间边界节点算法。物理模拟实验和挂网测试表明:该故障分区分段定位方法能够在线求解小电流接地故障段边界节点,缩小线路维护巡视范围。确定故障区间边界节点算法还可用于确定故障区相关负荷开关,为线路维护和馈线自动化提供依据。 展开更多
关键词 断层破碎带 配电自动化系统 单相接地故障 小电流系统 小电流接地 架空线路 电压分布 故障监测
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Ultrasonographic measurement of median nerve cross-sectional area reference values in a healthy Han population from Guiyang,China 被引量:3
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作者 Jun Chen Shan Wu Jun Ren 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第24期1883-1887,共5页
High-resolution ultrasonography was used to analyze the nerve cross-sectional area (CSA) of the median nerve at 7 sites: the wrist crease, pisiform bone, hamate bone, 6 cm proximal to the tip of the wrist crease, p... High-resolution ultrasonography was used to analyze the nerve cross-sectional area (CSA) of the median nerve at 7 sites: the wrist crease, pisiform bone, hamate bone, 6 cm proximal to the tip of the wrist crease, proximal forearm (where the nerve enters the pronator teres muscle), 4 cm proximal to the tip of the medial epicondyle, and mid-humerus (mid-point between elbow crease and axilla) in 200 healthy volunteers from Guiyang, China. Results showed similar CSA values between the left and right sides, but the CSA 6 cm proximal to the tip of the wrist crease, proximal forearm, 4 cm proximal to tip of the medial epicondyle, and mid-humerus in males was greater than that of females. Moreover, CSA values at the wrist crease, pisiform bone, and hamate bone were greater in the middle-aged and old groups when compared to the young group, and correlated with body mass and height. Thus, reference values of median nerve CSA of the upper limbs can facilitate the analysis of abnormal nerve conditions. 展开更多
关键词 ULTRASONOGRAPHY median nerve cross-sectional area Guiyang Han nationality
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Does the ratio of the carpal tunnel inlet and outlet cross-sectional areas in the median nerve reflect carpal tunnel syndrome severity? 被引量:6
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作者 Li Zhang Aierken Rehemutula +3 位作者 Feng Peng Cong Yu Tian-bin Wang Lin Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1172-1176,共5页
Although ultrasound measurements have been used in previous studies on carpal tunnel syndrome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome r... Although ultrasound measurements have been used in previous studies on carpal tunnel syndrome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome remains controversial. The cross-sectional areas of the median nerve at the tunnel inlet and outlet can show swelling and compression of the nerve at the carpal. We hypothesized that the ratio of the cross-sectional areas of the median nerve at the carpal tunnel inlet to outlet accurately reflects the severity of carpal tunnel syndrome. To test this, high-resolution ultrasound with a linear array transducer at 5–17 MHz was used to assess 77 patients with carpal tunnel syndrome. The results showed that the cut-off point for the inlet-to-outlet ratio was 1.14. Significant differences in the inlet-to-outlet ratio were found among patients with mild, moderate, and severe carpal tunnel syndrome. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.29 between mild and more severe(moderate and severe) carpal tunnel syndrome patients with 64.7% sensitivity and 72.7% specificity. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.52 between the moderate and severe carpal tunnel syndrome patients with 80.0% sensitivity and 64.7% specificity. These results suggest that the inlet-to-outlet ratio reflected the severity of carpal tunnel syndrome. 展开更多
关键词 nerve regeneration peripheral nerve injury ultrasonography carpal tunnel syndrome diagnosis cross-sectional area classification clinical laboratory technique electrodiagnosis median nerve 973 Program neural regeneration
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Optimal Minimum Number of CT Slices Required to Measure Cross Sectional Areas of Small Pulmonary Vessels
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作者 Shingo Sakamoto Shoichiro Matsushita +8 位作者 Akiyuki Kotoku Hayato Tomita Yuki Saito Shinji Saruya Shin Matsuoka Tsuneo Yamashiro Atsuko Fujikawa Kunihiro Yagihashi Yasuo Nakajima 《Open Journal of Medical Imaging》 2015年第2期71-77,共7页
The cross-sectional area (CSA) of small pulmonary vessels can be quantified by CT, which is a reliable method of evaluating vascular alterations in such vessels. However, the optimal number of slices required for accu... The cross-sectional area (CSA) of small pulmonary vessels can be quantified by CT, which is a reliable method of evaluating vascular alterations in such vessels. However, the optimal number of slices required for accurate quantitation remains unknown. We evaluated relationships among all slices at 10-mm interval and all slices at 3-cm interval, 6-cm interval, and 3-slices and found the closest correlation (0.939) between all slices at 10-mm intervals and 3-cm intervals. Thus, all slices at 3-cm intervals are suitable for accurately measuring CSA. 展开更多
关键词 COMPUTED Tomography CROSS-sectionAL area PULMONARY VESSELS Quantitative Analysis
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Saddle-Dolomite-Bearing Fracture Fillings and Records of Hot Brine Activity in the Jialingjiang Formation,Libixia Section,Hechuan Area of Chongqing City 被引量:1
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作者 HUANG Keke ZHONG Yijiang +2 位作者 HUANG Sijing LI Xiaoning FENG Mingshi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期195-208,共14页
Most vein minerals deposited in fractures of the Jialingjiang Formation from Libixia section, Hechan area include a large amount of saddle dolomite and accompanying celestite, calcite and fluorite. This study analyzed... Most vein minerals deposited in fractures of the Jialingjiang Formation from Libixia section, Hechan area include a large amount of saddle dolomite and accompanying celestite, calcite and fluorite. This study analyzed the nature, source, evolution of the fluids by plane-light petrography, fluid-inclusion methods, cathodoluminescence images, and stable isotopic compositions. The homogenization temperatures of two-phase aqueous fluid inclusions in dolomite range between 100 and 270℃. Combined with the jlSO data, it is suggested that the fluid responsible for the precipitation of fracture fillings have δ18O values between 10%o and 18‰ (relative to SMOW). The saddle dolomite and the accompanying minerals were the result of activity of dense brines at elevated temperatures. Moreover, analysis shows that the fluid was derived from a mixture of marine-derived brine and deeper circulating flow. This fluid was enriched in Sr during diagenesis and formed celestite in fracture and for regional mineralization. Dissolution of saddle dolomite was attributed to the cooling of Mg/Ca-decreased fluids, which may relate to a leaching of gypsum to celestite in surrounding carbonates. 展开更多
关键词 Libixia section Jialingjiang Formation saddle dolomite hot brine Hechuan area CHONGQING
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Tomography for Q of the Eastern Section of the Tianshan Area from High-frequency Attenuation of S-wave
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作者 Li Jin Zhou Longquan +1 位作者 Wang Huilin Xiang Yuan 《Earthquake Research in China》 CSCD 2018年第1期28-39,共12页
Based on the waveform data of 5,076 local earthquakes recorded at 25 stations in Xinjiang during the period from 2009 to 2014 and the observation reports provided by the Xinjiang Digital Seismic Network,a data set of ... Based on the waveform data of 5,076 local earthquakes recorded at 25 stations in Xinjiang during the period from 2009 to 2014 and the observation reports provided by the Xinjiang Digital Seismic Network,a data set of 19,140 attenuation factors t*is obtained by fitting the high-frequency attenuation of S-wave spectra with a genetic algorithm. The spatial distribution of Q_S is determined by inverting the t*data with seismic tomography. The results show that the average Q0 in eastern Tianshan is 520,and there is a significant correlation between the Q_S value distribution or attenuation characteristics it disclosed and the surface structure of the study area. The Q_S value is lower in the intersection area of the mountain basin which is located on the north and south sides of the Tianshan Mountains,and the high Q_S distribution is more concentrated inside the Tianshan orogenic belt. The M≥6. 0 earthquakes have been basically located in the Low-Q_S region since 1900. 24 high heat flow points in eastern Tianshan are located at the north and south of Tianshan Mountains where low Q_S exists,indicating a negative correlation. In addition,there is a positive correlation between the velocity structure and the attenuation structure in the study area,which reflects the consistency of the 2-D attenuation structure with the velocity structure and the two-dimensional density structure. 展开更多
关键词 Eastern section of the TIANSHAN area HIGH-FREQUENCY ATTENUATION of S-WAVE ATTENUATION operator t* Q TOMOGRAPHY
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汉江碾盘山枢纽工程二线船闸通航水流条件优化试验研究
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作者 徐俊锋 赵家强 《水运工程》 2026年第2期137-146,共10页
碾盘山枢纽已实现一期蓄水目标,针对碾盘山枢纽拟建二线船闸265 m设计方案上下游引航道口门区与主航道夹角较大、二线船闸通航水流条件不佳以及坝下河床调整变化造成枯水期航道出浅和航宽不足等问题,通过船闸通航水流条件及自航船模试验... 碾盘山枢纽已实现一期蓄水目标,针对碾盘山枢纽拟建二线船闸265 m设计方案上下游引航道口门区与主航道夹角较大、二线船闸通航水流条件不佳以及坝下河床调整变化造成枯水期航道出浅和航宽不足等问题,通过船闸通航水流条件及自航船模试验,开展碾盘山二线船闸方案优化试验研究。提出拟建二线船闸上游新建430 m导堤、下游进行复式开挖和喇叭口状开槽疏浚及坝下航道整治时低水期封堵左汊的工程措施,优化方案实施后现有一线船闸上下游通航条件有所改善,新建二线船闸通航水流条件较设计方案亦有所改善。船模试验验证表明,船舶通过引航道口门区及连接段时,航向能够保持稳定,舵角、漂距等参数均达标,通航安全性可靠。 展开更多
关键词 船闸 口门区 连接段 通航水流条件
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抑制SLC26A4通过调节心肌细胞凋亡和自噬来改善心肌肥厚
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作者 田明 洪葵 +1 位作者 彭易安 游春娇 《中国药理学通报》 北大核心 2026年第1期107-115,共9页
目的探讨抑制SLC26A4能否通过减少心肌细胞凋亡和自噬来改善心肌肥厚。方法将H9C2细胞分为对照组、PE组、NC组、PE+NC组、PE+SiRNA-SLC26A4组及SiRNASLC26A4组,部分采用200μmol·L^(-1) PE处理诱导肥厚,并通过腺病毒载体转染NC或SL... 目的探讨抑制SLC26A4能否通过减少心肌细胞凋亡和自噬来改善心肌肥厚。方法将H9C2细胞分为对照组、PE组、NC组、PE+NC组、PE+SiRNA-SLC26A4组及SiRNASLC26A4组,部分采用200μmol·L^(-1) PE处理诱导肥厚,并通过腺病毒载体转染NC或SLC26A4 siRNA。采用免疫荧光检测α-SMA,RT-qPCR检测SLC26A4、ANP、BNP及GSK-3βmRNA,Western blot检测Bcl-2、Bax、Caspase-3、p53、Beclin-1、LC3、P62蛋白水平,流式细胞术检测凋亡率。同时建立腹主动脉缩窄(AAC)致心肌肥厚大鼠模型,分为对照组、心肌肥厚组和SiRNA-SLC26A4组,后者注射siRNA-SLC26A4。通过HE染色观察细胞大小,RT-qPCR和Western blot检测相应分子表达。结果与对照组比较,PE组细胞相对面积及SLC26A4 mRNA表达均升高。与NC组相比,siRNA-SLC26A4组细胞相对面积、SLC26A4、ANP和BNP mRNA表达降低,而PE+NC组上述指标均升高;与PE+NC组相比,PE+siRNASLC26A4组各指标均下降。凋亡方面,siRNA-SLC26A4组凋亡率高于NC组,PE+NC组凋亡率低于NC组,而PE+siRNASLC26A4组凋亡率较PE+NC组升高。自噬相关指标显示,siRNA-SLC26A4组LC3Ⅱ/Ⅰ和Beclin-1表达高于NC组,p62表达降低;PE+siRNA-SLC26A4组LC3Ⅱ/Ⅰ和Beclin-1表达低于PE+NC组,p62表达上升。心肌肥厚组血清GSK-3β水平低于对照组,siRNA-SLC26A4组则高于心肌肥厚组。此外,心肌肥厚组Bcl-2/Bax比值低于对照组,p53和Caspase-3表达升高;siRNA-SLC26A4组Bcl-2/Bax比值高于心肌肥厚组,p53和Caspase-3表达降低。心肌肥厚组LC3Ⅱ/Ⅰ和Beclin-1表达高于对照组,p62降低;siRNA-SLC26A4组LC3Ⅱ/Ⅰ和Be-clin-1表达低于心肌肥厚组,p62表达上调。结论抑制SLC26A4通过调节心肌细胞凋亡和自噬来改善心肌肥厚。 展开更多
关键词 SLC26A4 心肌肥厚 心肌细胞肥大 凋亡 自噬 心肌细胞横截面积
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中青年颈椎失稳与颈部肌肉改变的相关性
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作者 路广琦 李靖 +11 位作者 孙馨悦 梁龙 刘广伟 周帅琪 毛瀚泽 马明明 崔莹 刘亚坤 胡家铭 朱立国 于杰 庄明辉 《中国组织工程研究》 北大核心 2026年第24期6220-6224,共5页
背景:中青年颈椎失稳的发生多始于颈部肌肉损伤,深入了解颈椎失稳发生时颈部肌肉的改变情况及两者之间的相关性,可为临床上开展中青年颈椎失稳的防治工作提供一定数据参考。目的:探讨中青年颈椎失稳与颈部肌肉改变的相关性。方法:通过... 背景:中青年颈椎失稳的发生多始于颈部肌肉损伤,深入了解颈椎失稳发生时颈部肌肉的改变情况及两者之间的相关性,可为临床上开展中青年颈椎失稳的防治工作提供一定数据参考。目的:探讨中青年颈椎失稳与颈部肌肉改变的相关性。方法:通过招募广告和中国中医科学院望京医院脊柱二科门诊纳入中青年颈椎C4/5角度失稳患者98例和健康受试者88例,年龄18-45岁,拍摄颈椎X射线片获得颈椎曲度、C4/5椎体角度位移数据,拍摄颈椎MRI片获得C4/5水平椎间盘信号强度、颈部肌肉(包括椎前肌、颈后侧深层肌肉和浅层肌肉)相对横截面积及脂肪比例。对颈椎失稳患者和健康受试者的基本信息与影像学检测结果进行单因素组间比较,对颈椎失稳患者C4/5角度位移与C4/5水平椎间盘信号强度、颈部肌肉相对横截面积及脂肪比例进行斯皮尔曼相关性分析。结果与结论:颈椎失稳组患者年龄、C4/5水平位移、C4/5角度位移与颈后侧深层肌肉脂肪比例均大于健康组(P<0.05),颈椎曲度、颈后侧深层肌肉相对横截面积小于健康组(P<0.05);斯皮尔曼相关性分析显示,C4/5角度位移和颈后侧深层肌肉相对横截面积之间存在负相关性(P<0.05)。结果表明,颈后侧深层肌肉改变与中青年颈椎失稳发生可能密切相关。 展开更多
关键词 颈椎失稳 颈部肌肉 肌肉横截面积 脂肪比例 中青年 颈椎病
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高速公路平行式加速车道渐变段长度计算模型对比研究
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作者 邵长桥 张东宇 《重庆交通大学学报(自然科学版)》 北大核心 2026年第1期1-6,14,共7页
平行式加速车道渐变段对保障高速公路合流区运行效率与安全具有关键作用,现有渐变段长度计算模型因考虑因素不同,导致结果差异显著。基于此,对比研究了多种平行式加速车道渐变段长度计算模型。基于实测数据与国内外文献,给出了不同模型... 平行式加速车道渐变段对保障高速公路合流区运行效率与安全具有关键作用,现有渐变段长度计算模型因考虑因素不同,导致结果差异显著。基于此,对比研究了多种平行式加速车道渐变段长度计算模型。基于实测数据与国内外文献,给出了不同模型理论计算结果;并以合流车辆平均运行速度及与主线车辆交通冲突数为指标,运用VISSIM仿真分析各模型所对应渐变段长度的合理性。研究结果表明:渐变率模型对应的车辆平均速度最高,横移换道模型的交通冲突数最少,换道行驶距离模型在平均速度与交通冲突数方面均表现最优;最终建议,在主线设计速度为120、100、80 km/h时,平行式加速车道渐变段长度分别取150、130、115 m。 展开更多
关键词 道路工程 高速公路合流区 平行式加速车道 渐变段长度 VISSIM仿真
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Baoziwan-Majiashan Area of Jiyuan Oilfield Analysis of Reservoir Characteristics and Main Control Factors in Long 4 5 Section
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作者 Zhengxi Cui Zhipeng Zhang Mingling Shen 《Open Journal of Yangtze Oil and Gas》 2024年第2期48-64,共17页
Based on the sheet, scanning electron microscope and high pressure mercury analysis method, this paper takes Jiyuan oilfield-Ma Jia mountain district 4 5 sandstone reservoir as the research object, from the reservoir ... Based on the sheet, scanning electron microscope and high pressure mercury analysis method, this paper takes Jiyuan oilfield-Ma Jia mountain district 4 5 sandstone reservoir as the research object, from the reservoir petrology, pore type and porosity, permeability, the system analyzed the reservoir characteristics and its control factors. The results show that the sandstone in the 4 5 section of Baoziwan-Majiashan area of Jiyuan oilfield is fine in size and high in filling content. The pore types were dominated by intergranular pores and dissolved pores, with a low face rate. The reservoir property is relatively poor, with mean porosity of 11.11% and mean permeability of 1.16 × 10<sup>−</sup><sup>3</sup> µm<sup>2</sup>. In the low porous, low otonic background, the development of relatively high pore hypertonic areas. Compaction and cementation should play a destructive role in reservoir properties, and dissolution should play a positive role in reservoir properties. Compaction adjusts the migration of clay minerals and miscellaneous bases in the original sediment in the study area, greatly reducing the porosity and permeability of the reservoir;the development of the cement cement, carbonate cementation and some quartz secondary compounds reduces the storage space;the dissolution effect, especially the secondary dissolution pores of the reservoir, which obviously improves the properties of the reservoir. 展开更多
关键词 Ordos Basin Jiyuan area Reservoir Characteristics Reservoir Control Factor Long 4 5 section
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脊柱微创通道镜系统辅助TLIF对腰椎间盘突出症患者椎间孔形态及腰椎疼痛和功能的影响
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作者 李威霖 刘军 +3 位作者 冯玉旭 吴宗方 顾越 储小敏 《临床误诊误治》 2026年第2期62-68,84,共8页
目的探讨脊柱微创通道镜系统辅助经椎间孔腰椎椎体间融合术(TLIF)对腰椎间盘突出症(LDH)患者椎间孔形态、腰椎疼痛及功能的影响。方法选取2023年1至12月就诊的76例LDH患者进行前瞻性研究。按随机数字表法分为微创组、传统组各38例。传... 目的探讨脊柱微创通道镜系统辅助经椎间孔腰椎椎体间融合术(TLIF)对腰椎间盘突出症(LDH)患者椎间孔形态、腰椎疼痛及功能的影响。方法选取2023年1至12月就诊的76例LDH患者进行前瞻性研究。按随机数字表法分为微创组、传统组各38例。传统组进行开放性TLIF,微创组使用脊柱微创通道系统辅助TLIF。比较两组围术期相关指标,手术前后腰椎疼痛、腰椎功能、椎间孔、椎旁肌、脊柱骨盆形态学参数变化以及术后并发症发生情况。结果微创组术中失血量、术后引流量少于传统组,手术时间、术后首次下床活动时间短于传统组(P<0.01);术后7 d、1个月、3个月、6个月微创组疼痛视觉模拟评分法评分低于传统组(P<0.05);术后3、6个月微创组椎间隙高度、椎间孔高度、椎间孔面积、多裂肌横断面面积、腰椎前凸角大于传统组,多裂肌至椎板距离、骨盆倾斜角小于传统组(P<0.05);术后3、6个月微创组OSWESTRY功能障碍指数低于传统组,日本骨科协会疗效评分、健康调查简表评价量表评分高于传统组(P<0.05);微创组并发症总发生率低于传统组(P<0.05)。结论脊柱微创通道系统辅助TLIF治疗LDH创伤小、术后恢复快,可缓解疼痛,有利于病灶节段椎间孔、椎旁肌、脊柱骨盆形态改善、腰椎功能早期恢复、提高生活质量。 展开更多
关键词 腰椎间盘突出症 脊柱微创通道 经椎间孔腰椎椎体间融合术 术后疼痛 椎间隙高度 多裂肌横断面面积 腰椎前凸角 OSWESTRY功能障碍指数
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探讨MRI影像学参数对椎间盘突出症外科手术患者预后的预测价值
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作者 陈飞 王玲玉 《影像研究与医学应用》 2026年第3期22-25,共4页
目的:研究MRI影像学参数对腰椎间盘突出症(LDH)外科手术患者预后的预测价值。方法:选取2022年7月—2024年7月南京张文新骨伤科医院收治的110例LDH患者为研究对象,所有患者均行外科手术治疗。按照预后结果分为预后不良组(n=31)和预后良好... 目的:研究MRI影像学参数对腰椎间盘突出症(LDH)外科手术患者预后的预测价值。方法:选取2022年7月—2024年7月南京张文新骨伤科医院收治的110例LDH患者为研究对象,所有患者均行外科手术治疗。按照预后结果分为预后不良组(n=31)和预后良好组(n=79)。比较两组各项基线资料、术前MRI影像学参数。以多因素Logistic回归分析筛选LDH外科手术患者预后不良的独立影响因素,选用受试者工作特征(ROC)曲线分析术前MRI影像学参数预测LDH外科手术患者预后不良的效能。结果:预后不良组吸烟、PfirrmaanIV级人数占比均高于预后良好组(P<0.05)。预后不良组术前各项MRI影像学参数均低于预后良好组(P<0.05)。经多因素Logistic回归分析显示,吸烟、PfirrmannIV级均是LDH外科手术患者预后不良的独立危险因素,而腰大肌横截面面积、多裂肌横截面面积、椎间孔面积均是LDH外科手术患者预后不良的独立保护因素(P<0.05)。ROC曲线显示,腰大肌横截面面积、多裂肌横截面面积、椎间孔面积联合预测LDH外科手术患者预后不良的曲线下面积(AUC)为0.951,灵敏度为0.903,特异度为0.911均优于各项参数单独预测。结论:术前MRI影像学参数中腰大肌横截面面积、多裂肌横截面面积及椎间孔面积联合应用于LDH外科手术患者预后预测中的价值较高。 展开更多
关键词 磁共振成像 腰椎间盘突出症 腰大肌横截面面积 多裂肌横截面面积 椎间孔面积
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股直肌横截面积、营养状态变化及不同热量与重症监护病房住院死亡率的相关性
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作者 王鸣 边伟帅 +2 位作者 刘平 颜承悦 吐达洪 《中华保健医学杂志》 2026年第1期73-77,共5页
目的 探讨股直肌横截面积(RFCSA)、营养状态变化及不同摄入热量与重症监护病房(ICU)住院死亡率的相关性。方法前瞻性纳入2022年6月~2024年6月入住首都医科大学附属北京世纪坛医院ICU的190例患者为研究对象,根据患者在ICU住院期间是否发... 目的 探讨股直肌横截面积(RFCSA)、营养状态变化及不同摄入热量与重症监护病房(ICU)住院死亡率的相关性。方法前瞻性纳入2022年6月~2024年6月入住首都医科大学附属北京世纪坛医院ICU的190例患者为研究对象,根据患者在ICU住院期间是否发生死亡事件,将其分为存活组(138例)和死亡组(52例)。测量患者RFCSA,采用危重症营养风险(NUTRIC)评分评估整体营养状况,计算患者热量摄入情况,通过医院电子病历系统采集一般资料和病情资料。按照建模组与验证组7∶3的比例,另于2024年7月~12月纳入患者82例作为验证组。采用单因素及二元logistic回归分析确定独立影响因素,绘制ROC曲线进行评价。结果单因素分析显示不同组的年龄、BMI、RFCSA、股直肌肌肉萎缩率、NUTRIC、热量摄入、血浆白蛋白、血气二氧化碳分压、氧合指数比较,差异均有统计学意义(P<0.05)。二元logistic回归结果显示,高RFCSA、更高热量摄入是患者发生死亡事件的独立保护因素,而更高的年龄、高股直肌肌肉萎缩率、高NUTRIC评分是独立危险因素(P<0.05),构建的预测模型曲线下面积(AUC)为0.989,敏感度为0.981,特异度为0.935,验证组ROC结果显示其AUC为0.983,敏感度为0.950,特异度为0.952。结论年龄、RFCSA、股直肌肌肉萎缩率、NUTRIC、热量摄入是ICU住院患者发生死亡事件的关键影响因素,构建的预测模型预测性能良好,可为评估患者预后提供量化工具。 展开更多
关键词 股直肌横截面积 营养状态 重症监护病房 住院死亡率 相关性
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地下室抗浮加固处理实例
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作者 傅文桥 伍定一 《建筑技术》 2026年第3期307-310,共4页
对某小区地下室在汛期来临时发生抗浮失效的问题进行了抗浮加固处理,根据检测鉴定报告、地勘资料等相关条件,采用了防洪补救设计+地下室底板抗浮加固设计的组合方案,对受损柱采取增大截面加固法加固,解决了该地下室的抗浮问题。关于地... 对某小区地下室在汛期来临时发生抗浮失效的问题进行了抗浮加固处理,根据检测鉴定报告、地勘资料等相关条件,采用了防洪补救设计+地下室底板抗浮加固设计的组合方案,对受损柱采取增大截面加固法加固,解决了该地下室的抗浮问题。关于地下室底板抗浮加固设计方案,综合考虑施工合理性、工程经济性和建筑功能要求等因素,对比了两种方案后,选择新增200 mm厚叠合板+均布压力型预应力锚杆的方案,并对现场已损伤严重的地下室底板拆除后新浇筑750 mm厚新底板。 展开更多
关键词 地下室 抗浮锚杆 抗浮加固 增大截面加固法
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CT定量参数对股骨粗隆间骨折与股骨颈骨折的鉴别价值
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作者 冷慧娟 《影像研究与医学应用》 2026年第2期29-31,35,共4页
目的:探讨CT定量参数对股骨粗隆间骨折与股骨颈骨折的鉴别价值。方法:选取2024年6月—2025年6月于常州市武进中医医院接受双髋关节扫描的82例髋关节骨折患者,根据术中探查骨折类型,分为股骨粗隆间组(n=39)与股骨颈组(n=43)。比较两组髋... 目的:探讨CT定量参数对股骨粗隆间骨折与股骨颈骨折的鉴别价值。方法:选取2024年6月—2025年6月于常州市武进中医医院接受双髋关节扫描的82例髋关节骨折患者,根据术中探查骨折类型,分为股骨粗隆间组(n=39)与股骨颈组(n=43)。比较两组髋部全髋、股骨颈、粗隆及粗隆间的骨密度(BMD)及髋部CT定量参数[股骨颈区域最小截面面积(CSA)、横截面惯性矩(CSMI)、截面模量Z值(Z)、屈曲比率(BR)、皮质骨厚度(CTh)和髋部轴长(HAL)]差异。参照术中探查结果,采用受试者工作特征(ROC)曲线分析CT定量参数对股骨粗隆间骨折与股骨颈骨折的鉴别诊断价值。结果:两组全髋、股骨颈、粗隆、粗隆间的BMD水平及CSMI、Z、CTh比较,差异无统计学意义(P>0.05);股骨粗隆间组的CSA、BR大于股骨颈组,HAL小于股骨颈组,差异有统计学意义(P<0.05);ROC曲线显示,CSA、BR、HAL鉴别股骨粗隆间骨折与股骨颈骨折类型的曲线下面积(AUC)分别为0.661、0.744、0.756,三者联合的AUC为0.883,效能最优。结论:髋部CT定量参数CSA、BR、HAL联合鉴别股骨粗隆间骨折与股骨颈骨折类型的效能较高,CSA、BR水平较低及HAL更大的患者跌倒后更易出现股骨颈骨折。 展开更多
关键词 CT定量参数 股骨颈区域最小截面面积 屈曲比率 髋部轴长 股骨粗隆间骨折 股骨颈骨折
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三峡库区(重庆段)土地利用碳排放效应研究
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作者 苏春梅 李贤蔚 何勇辉 《黑龙江科学》 2026年第1期43-46,50,共5页
为揭示三峡库区(重庆段)2019—2022年土地利用的碳排放效应变化,基于县域尺度建立土地利用碳排放计算模型,结合空间分析与灰色关联度法分析土地利用时空演变特征、碳排放强度及其影响因素。结果显示,研究区碳排放量总体呈增长趋势,总量... 为揭示三峡库区(重庆段)2019—2022年土地利用的碳排放效应变化,基于县域尺度建立土地利用碳排放计算模型,结合空间分析与灰色关联度法分析土地利用时空演变特征、碳排放强度及其影响因素。结果显示,研究区碳排放量总体呈增长趋势,总量从2019年的10267.1万t增至2022年的11546.9万t,增幅达12.5%,空间集聚特征显著,主城都市区贡献率达83.7%,建设用地与碳排放关联度最高,是核心驱动因子,未利用地影响最弱,碳排放增长主要源于城镇扩张与能源密集型产业的发展。提出差异化低碳管控策略,为研究区低碳减排政策的制定实施提供参考。 展开更多
关键词 土地利用 碳排放 三峡库区(重庆段) 低碳减排 建设用地 空间集聚
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