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Effects of combining multiple dose reduction techniques on coronary computed tomography angiography
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作者 Xiao-Lu Hu Pei-Kai Huang +2 位作者 Meng Zhang Jun Chen Meng-Qiang Xiao 《World Journal of Radiology》 2023年第2期32-41,共10页
BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awar... BACKGROUND Coronary computed tomography angiography(CCTA)is the preferred noninvasive examination method for coronary heart disease.However,the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase.AIM To explore the value of multiple dose reduction techniques for CCTA.METHODS Consecutive normal and overweight patients were prospectively divided into two groups:Group A1,patients who received multiple dose reduction scans(n=82);and group A2,patients who received conventional scans(n=39).The scan parameters for group A1 were as follows:Isocentric scan,tube voltage=80 kV,and tube current control using 80%smart milliampere.The scan parameters for group A2 were as follows:Normal position,tube voltage=100 kV,and smart milliampere.RESULTS The average effective doses(EDs)for groups A1 and A2 were 1.13±0.35 and 3.36±1.30 mSv,respectively.There was a statistically significant difference in ED between the two groups(P<0.01).Furthermore,noise was significantly lower,and both signal-to-noise ratio and contrast signal-to-noise ratio were higher in group A2 when compared to group A1(P<0.01).Moreover,the subjective image quality(IQ)scores were excellent in both groups,in which there was no significant difference in subjective IQ score between the two groups(P=0.12).CONCLUSION Multiple dose reduction scan techniques can significantly decrease the ED of patients receiving CCTA examinations for clinical diagnosis. 展开更多
关键词 Isocentric scanning Coronary heart disease Dose reduction techniques Coronary computed tomography angiography RADIATION
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Nonlinear optical properties of [(CH3)4N]Au(dmit)2 using Z-scan technique 被引量:1
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作者 孙香冰 任诠 +5 位作者 王新强 张光辉 杨洪亮 冯林 许东 刘智波 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2618-2622,共5页
The third-order optical nonlinearities of [(CH3)4N]Au(dmit)2 (dmit = 4,5-dithiolate-1,3-dithiole-2-thione) at 532 nm and 1064 nm are investigated using the Z-scan technique with pulses of picoseconds duration. T... The third-order optical nonlinearities of [(CH3)4N]Au(dmit)2 (dmit = 4,5-dithiolate-1,3-dithiole-2-thione) at 532 nm and 1064 nm are investigated using the Z-scan technique with pulses of picoseconds duration. The Z-scan spectra reveal a strong nonlinear absorption (reverse saturable absorption) and a negative nonlinear refraction at 532 nm. No nonlinear absorption is observed at 1064 nm. The molecular second-order hyperpolarizability γ for the [(CH3)4N]Au(dmit)2 molecule at 532nm is estimated to be as high as (2.1 ±0.1) × 10^-31 esu, which is nearly three times larger than that at 1064 nm. The mechanism responsible for the difference between the results is analysed. Nonlinear transmission measurements suggest that this material has potential applications in optical limiting. 展开更多
关键词 third-order optical nonlinearity organo-metallic compounds Z-scan technique
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Analysis of Recent Secure Scan Test Techniques
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作者 Cheng Xing Sungju Park Ji Zhao 《Journal of Software Engineering and Applications》 2016年第3期91-101,共11页
Side channel attack may result in user key leakage as scan test techniques are applied for crypto-graphic chips. Many secure scan designs have been proposed to protect the user key. This paper meticulously selects thr... Side channel attack may result in user key leakage as scan test techniques are applied for crypto-graphic chips. Many secure scan designs have been proposed to protect the user key. This paper meticulously selects three current scan test techniques, analyses their advantages and disadvantages and also compares them in security and area overhead. Users can choose one of them according to the requirements and further combination can be implemented to achieve better performance. 展开更多
关键词 Side Channel Attack scan Test techniques Secure scan Designs
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Nonlinear optical characterization of phosphate glasses based on ZnO using the Z-scan technique
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作者 Masoumeh Shokati Mojdehi Wan Mahmood Mat Yunus +2 位作者 Khor Shing Fhan Zainal Abidin Talib N.Tamchek 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期594-598,共5页
The nonlinear optical properties of a phosphate vitreous system [(ZnO)x-(MgO)30-x-(P2O5)70], where x=8, 10, 15, 18, and 20 mol% synthesized through the melt-quenching technique have been investigated by using th... The nonlinear optical properties of a phosphate vitreous system [(ZnO)x-(MgO)30-x-(P2O5)70], where x=8, 10, 15, 18, and 20 mol% synthesized through the melt-quenching technique have been investigated by using the Z-scan technique. In the experiment, a continuous-wave laser with a wavelength of 405 nm was utilized to determine the sign and value of the nonlinear refractive (NLR) index and the absorption coefficient with closed and opened apertures of the Z-scan setup. The NLR index was found to increase with the ZnO concentration in the glass samples by an order of 10-10 cm2·W-1. The real and imaginary parts of the third-order nonlinear susceptibility were calculated by referring to the NLR index (n2) and absorption coefficient (β) of the samples. The value of the third-order nonlinear susceptibility was presented by nonlinear refractive or absorptive behavior of phosphate glasses for proper utilization in nonlinear optical devices. Based on the measurement, the positive sign of the NLR index shows a self-focusing phenomenon. The figures of merit for each sample were calculated to judge the potential of phosphate glasses for application in optical switching. 展开更多
关键词 Z-scan technique nonlinear refractive index nonlinear absorption coefficient phosphate glasses
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Z-Scan technique: To measure the total protein and albumin in blood
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作者 A.N. Dhinaa P.K. Palanisamy 《Journal of Biomedical Science and Engineering》 2010年第3期285-290,共6页
Z-scan technique is an effective tool for measuring the optical nonlinearity of the materials. By using this technique the measurement was made for total protein and albumin. The nonlinear refractive index of the tota... Z-scan technique is an effective tool for measuring the optical nonlinearity of the materials. By using this technique the measurement was made for total protein and albumin. The nonlinear refractive index of the total protein and albumin were found to vary linearly with concentration. Hence by calculating the nonlinear refractive index it is possible to measure their concentration in the sample. The values measured thus are found in equivalence with conventional colorimetric method. 展开更多
关键词 Z-scan technique Nonlinear Refractive INDEX TOTAL PROTEIN ALBUMIN
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Investigation on Third-Order Optical Nonlinearities of Two Organometallic Dmit2- Complexes Using Z-Scan Technique
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作者 He-Liang Fan Quan Ren +6 位作者 Xin-Qiang Wang Ting-Bin Li Jing Sun Guang-Hui Zhang Dong Xu Gang Yu Zhi-Hua Sun 《Natural Science》 2009年第2期136-141,共6页
The third-order nonlinear optical properties of two dmit organometallic complexes, [(CH3)4N] [Au(C3S5)2] (MeAu) and [(CH3)4N][Ni(C3S5)2] (Me Ni) in acetone solutions, were characterized us- ing a short pulse Z-scan te... The third-order nonlinear optical properties of two dmit organometallic complexes, [(CH3)4N] [Au(C3S5)2] (MeAu) and [(CH3)4N][Ni(C3S5)2] (Me Ni) in acetone solutions, were characterized us- ing a short pulse Z-scan technique at 1064 nm wavelength. Self-defocusing effects were found in both samples and stronger saturable absorp-tion was observed in MeNi solution comparing with that of MeAu. The origins were analyzed for the differences between the results. Two figures of merit W and T were also calculated to evalu-ate the suitability of two materials for all-optical integrated devices. The results of W=22.84 and T≈0 of MeAu make it an excellent candidate for the all-optical applications. 展开更多
关键词 Z-scan technique THIRD-ORDER Nonlinearity Metal-dmit COMPLEXES Figure of Merit.
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Insight into microstructure evolution on anti-corrosion property of Al_(x)CoCrFeNiC_(0.01) high-entropy alloys using scanning vibration electrode technique 被引量:1
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作者 Bo-Kai Liao Zhan-Xiang Liang +6 位作者 Zhi-Gang Luo Yue Liu Hao-Wei Deng Tao Zhang Xing-Peng Guo Qi-Sen Ren Hong-En Ge 《Rare Metals》 SCIE EI CAS CSCD 2023年第10期3455-3467,共13页
The effect of micro structure on the corrosion resistance of Al_(x)CoCrFeNiC_(0.01)(x=0.2,0.7,and 1.2)high-entropy alloys(HEAs) was systematically studied in this work.The microstructure evolution by regulating the Al... The effect of micro structure on the corrosion resistance of Al_(x)CoCrFeNiC_(0.01)(x=0.2,0.7,and 1.2)high-entropy alloys(HEAs) was systematically studied in this work.The microstructure evolution by regulating the Al content was analyzed in detail.Corrosion behavior was in situ monitored using the scanning vibration electrode technique,as well as some traditional electrochemical measurements.It is interesting to find that the compositions of body-centered cubic(bcc) and face-centered cubic(fcc)phases changed with the rising Al content,while the corresponding electrochemical responses for both phases were discriminated using the scanning Kelvin probe force microscopy method.Cr element was mainly distributed in the bcc phase for Al0.2(x=0.2) alloy,while its distribution changed to the fcc phase for the A10.7 and Al1.2alloys.The micro-galvanic corrosion cells formed between Cr-depleted and Cr-rich phases,resulting in the localized corrosion behaviors for the Al_(x)CoCrFeNiC_(0.01) HEAs,and the order for anti-corrosion property was Al0.2>Al1.2> Al0.7 HEAs. 展开更多
关键词 High-entropy alloy Corrosion Mechanical property scanning vibration electrode technique
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Evaluation of the Functional Impression Technique with Various Impression Materials on the Surface Topography of Dental Stone Casts and Their Effect on Retention
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作者 Manal R. Alammari 《Open Journal of Stomatology》 2018年第7期258-270,共13页
Background: The accuracy of the final prosthesis is affected by the final impression technique and master cast production. The aim of the present study was to evaluate the effect of the functional impression technique... Background: The accuracy of the final prosthesis is affected by the final impression technique and master cast production. The aim of the present study was to evaluate the effect of the functional impression technique with various impression materials on the surface characteristic of dental stone casts and their clinical effect on the retention of complete dentures. Method: Specimens of three impression materials/stone casts were fabricated. The specimens of the impression materials/stone casts were divided into three equal groups (I, II, and III). The impression materials used were as follows: tissue conditioner group (I), zinc oxide (ZEO) (group II) and poly (vinyl siloxane) (PVS) (group III). Cylindrical split aluminium moulds were designed to receive the impression materials and the stone mixture. The surface roughness of the stone cast specimens of the three groups (I, II, and III) was measured with a surface profilometer and analyzed by a scanning electron microscope. A clinical study included five severely resorbed mandibular edentulous alveolar ridges and edentulous maxillary arches. Each subject received three heat-cured acrylic resin dentures, fabricated using the functional impression technique. The three dentures were identical except for the different impression materials used from Groups I, II and III. The retentive force of each denture for each subject was measured. Result: The results of this study revealed that the mean value of surface roughness of the stone cast surface of group I was higher than group II and group III. A statistically significant difference was observed in surface roughness and the retentive dislodging force between the three studied groups. Although using a tissue conditioner as a functional impression material led to a high level of surface roughness and good retention, it could not produce the same smooth surface quality of PVS or ZEO. These data were supported by SEM analysis. The complete dentures for these patients require important oral and denture hygiene care. Conclusion: Complete dentures made using functional impression technique with PVC as a final impression material are more comfortable, retentive and stable. 展开更多
关键词 IMPRESSION techniques IMPRESSION Materials Surface Roughness scanning Electron MICROSCOPE and Retention of Complete DENTURE
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Immediate-release Mechanism of Dehydrotrametenolic Acid and Dehydroeburicoic Acid in Poriae Cutis Total Triterpenoids Tablets Based on Liquid-solid Compact Technique
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作者 Xuesheng YAN Dandan SUN +2 位作者 Yanwei GUO Xingang XU Beibei YU 《Medicinal Plant》 2017年第4期37-39,47,共4页
[Objectives]To study the immediate-release mechanism of dehydrotrametenolic acid and dehydroeburicoic acid in Poriae Cutis total triterpenoids tablets by liquid-solid compacts technique.[Methods] Taking dehydrotramete... [Objectives]To study the immediate-release mechanism of dehydrotrametenolic acid and dehydroeburicoic acid in Poriae Cutis total triterpenoids tablets by liquid-solid compacts technique.[Methods] Taking dehydrotrametenolic acid and dehydroeburicoic acid as indicators,differences in dissolution were compared between liquid-solid compressed tablets and crude drug of total triterpenoids in Poriae Cutis;crude drug,powder of liquid-solid compressed tablets and excipients of liquid-solid compressed tablets were characterized by differential scanning calorimetry( DSC).[Results]Liquid-solid compact technique could significantly improve dissolution rate of dehydrotrametenolic acid and dehydroeburicoic acid. The total dissolution rate of dehydrotrametenolic acid and dehydroeburicoic acid in Poriae Cutis total triterpenoids tablets was 92%,t50( time for 50% total dissolution rate) and t_D( time for 63. 2% total dissolution rate) were 11. 18 min and 22. 71 min; the total dissolution rate of dehydrotrametenolic acid and dehydroeburicoic acid in crude drug of total triterpenoids was 29%,and t50 and t_D were231. 06 min and 359. 23 min. DSC showed that there was no mutual interaction between excipients and total triterpenoids in Poriae Cutis; on the DSC curve for powder of liquid-solid compressed tablets,the absorption peak vanished completely,indicating that the drug exists in the amorphous form in the liquid-solid powder.[Conclusions] Liquid-solid compact technique can increase the dissolution rate of total triterpenoids in Poriae Cutis and allow rapid release of poorly water soluble drugs. 展开更多
关键词 Liquid-solid compact technique Poriae Cutis Total TRITERPENOIDS In VITRO dissolution Differential scanning CALORIMETRY
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磁共振药代动力灌注扫描在鉴别段样强化肉芽肿性乳腺炎与浸润性导管癌中的价值研究 被引量:1
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作者 陈艳 吴晓燕 +3 位作者 张敏 黄学菁 成建明 郑李韵 《磁共振成像》 CAS CSCD 北大核心 2024年第3期177-182,共6页
目的 探讨基于压缩感知技术的磁共振药代动力灌注扫描对段样强化的特发性肉芽肿性乳腺炎(idiopathic granulomatous mastitis,IGM)与浸润性导管癌(invasive ductal carcinoma,IDC)的鉴别诊断价值。材料与方法 回顾性分析27例段样强化、... 目的 探讨基于压缩感知技术的磁共振药代动力灌注扫描对段样强化的特发性肉芽肿性乳腺炎(idiopathic granulomatous mastitis,IGM)与浸润性导管癌(invasive ductal carcinoma,IDC)的鉴别诊断价值。材料与方法 回顾性分析27例段样强化、无脓肿型IGM和15例IDC患者的临床及影像资料,均行磁共振药代动力灌注扫描。采用Fisher精确检验、t检验、χ^(2)检验比较两组月经状态、年龄、内部强化方式的差异,采用t检验、Mann Whitney U检验筛选出两组容积转运常数(volume transport constant,K^(trans))、速率常数(rate constant,K_(ep))、血管外细胞外间隙容积分数(extravascular extracellular volume fraction,Ve)值中的差异项,用二元logistic线性回归分析其与IDC的危险系数,并绘制受试者工作特征(receiver operating characteristic,ROC)曲线。结果 两组年龄、月经状态差异均有统计学意义(P=0.001、0.003),而内部强化方式差异无统计学意义(P=0.883)。磁共振药代动力灌注扫描:IGM组K^(trans)值[(0.274±0.163)min^(-1)]低于IDC组[(0.451±0.257) min^(-1)],IGM组K_(ep)值[(0.618±0.245)min^(-1)]低于IDC组[(0.856±0.420) min^(-1)],且两组间K^(trans)及K_(ep)值的差异有统计学意义(P=0.013,0.012)。两组Ve值为IGM组(0.531±0.320)min^(-1)、IDC组(0.629±0.323)min^(-1),差异无统计学意义(P=0.182)。二元logistic线性回归:K^(trans)值的优势比(odds ratios,OR)=2.243[95%置信区间(confidence interval,CI):0.652~6.294](P=0.021),绘制ROC曲线显示,约登指数、敏感度、特异度分别为0.585、73.3%、85.2%,曲线下面积(area under the curve,AUC)=0.778 (95%CI:0.623~0.891)(P=0.001)。结论 基于压缩感知技术的磁共振药代动力灌注扫描所得K^(trans)值对以段样强化为表现的IGM、IDC有鉴别诊断价值。 展开更多
关键词 特发性肉芽肿性乳腺炎 浸润性导管癌 磁共振药代动力灌注扫描 压缩感知 磁共振成像
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一种旋转移相式高功率微波反射阵列天线
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作者 许亮 张强 +4 位作者 袁成卫 刘金亮 孙云飞 龚鸿州 刘东琪 《强激光与粒子束》 CAS CSCD 北大核心 2024年第1期5-11,共7页
利用旋转移相技术的几何相位调控方法,提出一种基于传输相位差概念的波束扫描高功率微波反射阵列天线。电磁仿真结果表明,所设计的三叉戟形反射阵列天线单元工作于9.5~10.5 GHz,在0~40°入射角度下具有360°范围内的线性相位调... 利用旋转移相技术的几何相位调控方法,提出一种基于传输相位差概念的波束扫描高功率微波反射阵列天线。电磁仿真结果表明,所设计的三叉戟形反射阵列天线单元工作于9.5~10.5 GHz,在0~40°入射角度下具有360°范围内的线性相位调控能力,真空条件下的功率容量达到1.11 GW。采用该单元设计了半径为200 mm的圆形口径反射阵列天线,并使用全波仿真软件进行验证,利用口径相位分布的可重构特性,所设计的反射阵列天线可以实现±40°范围内的波束扫描。在10 GHz时,波束扫描过程中的增益下降小于1.7 dB,最大增益达到31.1 dBi,对应口径效率为73.42%,最低口径效率超过50%,副瓣电平和轴比始终低于-18.7 dB和1.6 dB。 展开更多
关键词 旋转移相技术 波束扫描 反射阵列天线 高功率微波 功率容量
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用双色Z-SCAN法研究热效应的弛豫过程 被引量:1
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作者 贾振红 周骏 +1 位作者 傅冠久 李劬 《量子电子学报》 CAS CSCD 1997年第1期40-43,共4页
用双色Z-SCAN法研究了热效应的弛豫过程,首次给出了为得到最大的测量灵敏度所满足的泵浦光束和参考光束的几何条件.在实验上对偶氮染料有机物热弛豫时间进行了测量。
关键词 热效应 双色Z-scan 弛豫过程 泵浦光 激光
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超高真空低温强磁场扫描隧道显微镜的原理及其在石墨烯量子点中的应用
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作者 符中秋 王芷 +1 位作者 王引书 何林 《物理实验》 2024年第5期1-11,共11页
扫描隧道显微镜具有原子级实空间分辨与原位电子态密度探测能力,是材料表面结构及性质表征的常用工具,特别是在近20年来以石墨烯为代表的二维材料电学性质的研究中发挥了重要作用.本文介绍了扫描隧道显微镜的基本原理以及超高真空低温... 扫描隧道显微镜具有原子级实空间分辨与原位电子态密度探测能力,是材料表面结构及性质表征的常用工具,特别是在近20年来以石墨烯为代表的二维材料电学性质的研究中发挥了重要作用.本文介绍了扫描隧道显微镜的基本原理以及超高真空低温强磁场扫描隧道显微镜的关键技术,并且以石墨烯量子点的特性为例,介绍了超高真空低温强磁场扫描隧道显微镜在石墨烯量子点的制备、电学性质的表征以及量子点中准束缚态在磁场作用下的演化研究中的应用. 展开更多
关键词 扫描隧道显微镜 扫描隧道谱 低温技术 二维材料 石墨烯量子点
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双定位像联合FAST技术减少胸部CT辐射剂量的效果分析
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作者 邵琪琪 钱琦 +1 位作者 姜黄维 王振 《浙江临床医学》 2024年第8期1235-1237,共3页
目的探讨双定位像联合快速辅助扫描技术(FAST)减少胸部CT辐射剂量的效果。方法选取2020年12月至2021年5月行胸部CT检查的门诊患者160例,采用随机数字表法分为观察组和对照组,每组各80例。两组均采用FAST技术,对照组为单定位像,观察组为... 目的探讨双定位像联合快速辅助扫描技术(FAST)减少胸部CT辐射剂量的效果。方法选取2020年12月至2021年5月行胸部CT检查的门诊患者160例,采用随机数字表法分为观察组和对照组,每组各80例。两组均采用FAST技术,对照组为单定位像,观察组为双定位像。比较两组CT图像的质量、信噪比(SNR)、对比噪声比(CNR)、容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)、有效剂量(ED)及体型特异性剂量估算(SSDE)。结果观察组与对照组图像质量评分、SNR和CNR值比较,差异无统计学意义(P>0.05)。两组CTDIvol、DLP、ED及SSDE比较,差异有统计学意义(P<0.001)。结论采用双定位像联合FAST技术较常规单定位像胸部CT检查,可明显降低患者的辐射剂量,同时图像质量可以满足临床诊断要求。 展开更多
关键词 胸部CT 定位像 快速辅助扫描技术 图像质量 辐射剂量
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不同扫描体位和定位像方向对单髋关节CT图像及辐射剂量影响
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作者 蒋栋栋 王亚囡 +2 位作者 周蕾 孙澳 吕国义 《影像科学与光化学》 CAS 2024年第1期23-28,共6页
在自动管电流调制(ATCM)技术下,探讨不同扫描体位及定位像方向在单髋关节CT中对图像和辐射剂量的影响。将120例进行单髋关节CT检查患者随机分为4组。A组常规扫描以身体正中线作矢状垂直定位线,定位像前后位+左侧位,扫描视野选择大体型,... 在自动管电流调制(ATCM)技术下,探讨不同扫描体位及定位像方向在单髋关节CT中对图像和辐射剂量的影响。将120例进行单髋关节CT检查患者随机分为4组。A组常规扫描以身体正中线作矢状垂直定位线,定位像前后位+左侧位,扫描视野选择大体型,其余三组以患侧髋关节为中心的等中心扫描,扫描视野均选择小体型,其中B组定位像采用前后位+X线管靠近身体长轴的侧位像;C组采用前后位+X线管远离身体长轴的侧位像;D组仅采用前后位。比较4组患者的容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP),同时测量并计算图像客观噪声、信噪比(SNR)、对比信噪比(CNR),评估图像主观噪声、条纹伪影及诊断信心度。结果显示4组间客观噪声、SNR、CNR、CTDIvol、DLP的差异具有统计学意义(P<0.01),组间比较显示,C与D组各项的差异无统计学意义(均P>0.05),其余组间比较各项的差异具有统计学意义(P<0.01),C、D组辐射剂量整体降低16%~35%;4组图像在主观噪声、条纹伪影及诊断信心度上的差异无统计学意义(P>0.05)。在基于最后一次采集定位像信息的ATCM系统中进行单髋关节CT扫描时,推荐等中心扫描方案同时选择小体型扫描视野,将前后定位像或选择X线管远离身体长轴的侧位定位像作为最后一次执行计划,能保证图像质量同时进一步优化辐射剂量。 展开更多
关键词 髋关节 定位像 等中心扫描 自动管电流调制技术 辐射剂量
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数字化印模技术应用于口腔种植修复的精度分析
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作者 唐天弘 朱陈元 翁维民 《口腔颌面修复学杂志》 2024年第2期97-102,共6页
目的:通过口内扫描杆获取的数字化印模与传统硅橡胶印模在种植修复中精度的差异,为临床提供更加准确可靠的种植印模方式。方法:本研究根据排纳标准将20位受试者的32颗种植体纳入研究。将传统硅橡胶印模法和口内扫描数字化印模法确定的... 目的:通过口内扫描杆获取的数字化印模与传统硅橡胶印模在种植修复中精度的差异,为临床提供更加准确可靠的种植印模方式。方法:本研究根据排纳标准将20位受试者的32颗种植体纳入研究。将传统硅橡胶印模法和口内扫描数字化印模法确定的种植体位置与CBCT相比较。测量参数为种植体植入点、根尖点和角度偏差。测量结果由SPSS 21.0进行统计学分析。结果:传统方式测量的种植体植入点偏差为(0.731±0.296)mm,根尖点为(0.982±0.310)mm;数字化印模方式测量的种植体植入点偏差为(0.755±0.274)mm,根尖点为(0.921±0.390)mm。两种方式测得的种植体植入点和根尖点的位置偏差无统计学意义(P>0.05)。数字化印模方式测定的种植体角度偏差(1.172±0.262)°显著优于传统印模方法(2.805±0.908)°(P<0.05)。结论:传统硅橡胶印模法和口内扫描数字化印模法的精度在种植体植入点、根尖点上无差异,在角度上口内扫描数字化印模法精度优于传统硅橡胶印模法。在短跨度牙列的种植印模中,口内扫描数字化有良好的应用前景。 展开更多
关键词 印模精度 数字化印模技术 口内扫描杆
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螺旋CT扫描技术在肺磨玻璃结节良、恶性定性鉴别诊断中的应用
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作者 马秋月 王海波 王潇偲 《罕少疾病杂志》 2024年第9期45-46,共2页
目的 深入探究螺旋CT扫描技术在鉴别肺磨玻璃结节(GGN)良恶性方面的应用价值,旨在为临床诊疗提供更加精确可靠的依据。方法 选取2020年7月-2023年12月本院收治GGN 101例为研究对象。所有研究对象均行螺旋CT扫描检查,以病理检查为“金标... 目的 深入探究螺旋CT扫描技术在鉴别肺磨玻璃结节(GGN)良恶性方面的应用价值,旨在为临床诊疗提供更加精确可靠的依据。方法 选取2020年7月-2023年12月本院收治GGN 101例为研究对象。所有研究对象均行螺旋CT扫描检查,以病理检查为“金标准”,分析螺旋CT扫描技术诊断GGN良、恶性的效果,总结不同性质GGN影像学及形态学特征。结果 经病理确诊:良性GGN36例,恶性GGN65例。101例GGN经螺旋CT扫描技术检查,良性GGN33例,其中AAH26例,炎症10例,恶性GGN64例,其中原位腺癌29例,浸润型腺.癌28例,微浸润腺癌7例。其中良性漏诊3例,符合率91.66%(33/36),恶性漏诊1例.,符合率98.46%(64/65)。螺旋CT扫描技术对GGN良、恶性灵敏度91.66%(33/36),特异度98.46%(64/65),阳性预测值97.05%(33/34),阴性预测值9552%(64/67)。GGN良、恶性组螺旋CT扫描技术影像学及形态学特征比较,差异有统计学意义(P<005)。结论 螺旋CT扫描技术在GGN良、恶性定性鉴别诊断中的应用具有重要意义,为临床医生提供有力的诊断依据,有助于提高GGN的诊断准确性。 展开更多
关键词 螺旋CT扫描技术 鉴别 肺磨玻璃结节 良性 恶性
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应用于隧道窑的产品追溯系统的设计 被引量:1
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作者 张国权 耿红生 《工业控制计算机》 2024年第4期116-117,共2页
基于扫码技术和Access数据库技术,设计了一套产品追溯系统。其特点是通过追溯装载产品的窑车,间接进行产品追溯,使得追溯系统可应用在隧道窑等高温环境中。通过追溯系统,生产管理方可方便地按生产批号或日期查询生产过程数据,便于质量... 基于扫码技术和Access数据库技术,设计了一套产品追溯系统。其特点是通过追溯装载产品的窑车,间接进行产品追溯,使得追溯系统可应用在隧道窑等高温环境中。通过追溯系统,生产管理方可方便地按生产批号或日期查询生产过程数据,便于质量问题的追溯和责任认定。系统已在江苏某企业稳定运行六个月,发现了一个影响产品质量的因素,提高了产品的良品率。 展开更多
关键词 隧道窑 扫码技术 ACCESS数据库 产品追溯
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微生物诱导碳酸钙沉淀技术对花岗岩残积土渗透性的影响规律研究 被引量:1
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作者 张永杰 唐银港 +2 位作者 欧阳健 罗志敏 谭长江 《交通科学与工程》 2024年第3期1-8,107,共9页
用花岗岩残积土填筑的路基具有水稳性差、渗透系数大、易受降雨冲刷等特点。为探讨微生物诱导碳酸钙沉淀(microbial induced calcite precipitation,MICP)技术对花岗岩残积土渗透系数的影响规律及作用机理,测定MICP固化前后重塑花岗岩... 用花岗岩残积土填筑的路基具有水稳性差、渗透系数大、易受降雨冲刷等特点。为探讨微生物诱导碳酸钙沉淀(microbial induced calcite precipitation,MICP)技术对花岗岩残积土渗透系数的影响规律及作用机理,测定MICP固化前后重塑花岗岩残积土试样的渗透系数,并对固化前后的试样进行碳酸钙质量分数测定、核磁共振扫描、电镜扫描以及X射线衍射分析。结果表明:1) MICP技术能使花岗岩残积土试样的渗透系数降低两个数量级,且在试验范围内,将各因素按照对渗透系数的影响程度从大到小排列,依次为:胶结液浓度、固化次数、灌注液量。同时,最佳固化条件为灌注液量40 mL、胶结液浓度1.0 mol/L、固化16次。2)固化产生的沉淀填充在花岗岩残积土孔隙中,致使孔隙间的连通性变差,孔隙率下降。总体上,越靠近注入端碳酸钙的质量分数越大,固化效果越好。3)簇状的方解石碳酸钙有效胶结了原本松散的土颗粒,堵塞了土颗粒孔隙间的渗流通道,降低了试样的渗透系数。 展开更多
关键词 花岗岩残积土 渗透系数 微生物诱导碳酸钙沉淀技术 核磁共振 扫描电镜 X射线衍射
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张口受限患者的数字化修复1例及文献回顾
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作者 杨铮灏 朱熙亭 +2 位作者 李晨 周敏 甘雪琦 《口腔疾病防治》 2024年第3期216-222,共7页
目的探讨因系统性硬皮病导致的特殊张口受限(小口畸形)患者取模困难时准确得到其口内模型的方法。方法本研究遵循医学伦理,并获得患者知情同意。对1例肯氏Ⅰ类下颌牙列缺损的硬皮病张口受限患者应用以数字化技术为主导,结合传统印模方... 目的探讨因系统性硬皮病导致的特殊张口受限(小口畸形)患者取模困难时准确得到其口内模型的方法。方法本研究遵循医学伦理,并获得患者知情同意。对1例肯氏Ⅰ类下颌牙列缺损的硬皮病张口受限患者应用以数字化技术为主导,结合传统印模方式的分段印模方案。根据其本身的左、右下颌牙列制作个别托盘后进行分段式取模,同时口内扫描取得上、下颌软硬组织形态数据。在获得各部分模型后,对下颌模型进行扫描和数字对齐,形成最终的牙列模型,并借助CAD/CAM技术设计制作最终的可摘局部义齿,同时结合文献对张口受限患者可摘局部义齿修复诊疗进行回顾分析。结果义齿固位良好,获得了良好的修复效果,患者对该义齿的咀嚼效率等功能行使均满意。文献复习结果表明,数字化技术结合传统印模方法,利用计算机进行拟合可以准确地得到患者口内模型,为后续修复做好基础工作。然而患者下颌牙列前段无牙时该流程误差可能较大,仍需要进一步完善。结论以数字化技术为主导,结合传统印模方式的分段印模方案用于修复张口受限患者的牙列缺损效果良好,患者就医体验、满意度高,值得临床推广。 展开更多
关键词 小口畸形 硬皮病 张口受限 牙列缺损 口腔印模技术 分段式取模 口内扫描 数字化对齐 可摘局部义齿 计算机辅助设计/计算机辅助制造
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