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1.
本文报道了我院采用Ａｉｒ－ＣＴ扫描诊断３５例ＣＰＡ蛛网膜粘连并由此探索出一种较好治疗方法的经验。认为：Ａｉｒ－ＣＴ扫描是诊断ＣＡＰ区蛛网膜粘连最简便、可靠的方法。 相似文献
2.
本文应用我国推广普及型ＣＴ（ＣＴＭＡＸ－Ⅱ），根据世界卫生组织（ＷＨＯ）提出的ＱＡ、ＱＣ体系的原则，制定我院ＣＴ室十个扫描技术规范和ＣＴ诊断技术规范等，和ＣＴ日常维护（ＰＭ）规程和ＣＴ图像考贝后处理等３个规程． 相似文献
3.
《CT理论与应用研究》1995,(2)
西门子公司ＡＲ·Ｃ断面扫描系统和ＩＭＰＡＣＴ－磁共振成像系统在煤炭部总医院应用的经验煤炭部总医院影像科，１０００２８数字形像设备的配置和应用情况，已成为衡量现代化医院的重要标准．而Ｘ线计算机断面扫描系统和磁共振成像系统，又是最重要的两大数字影像设备．... 相似文献
4.
脑血管意外后抑郁症量表与CT表现相关研究 总被引：1，自引：0，他引：1
应用ＺｕｎｇＤＨＡＭＤＳＣＬ－９０－Ｄ调查了９８例脑血管意外患者的抑郁心理状态，ＣＴ片上观察的指标有ＡＰ％、ＰＰ％、ＬＹ％和病灶部位（皮层或层下）。结果表明：（１）ＰＳＤ的发生率较高，急性期为４３％，慢性期为５５％；（２）不论皮层还是皮层下病灶，急性期左半球前部损伤均产生较高的抑郁程度，ＡＰ％与抑郁程度呈显著负相关，（３）慢性期患者ＣＴ上损伤部位与ＰＳＤ关系不明显，作者的结论是：ＰＳＤ量表得分与有一定关系，ＣＴ可预测ＰＳＤ发生的可能性及抑郁程度大小． 相似文献
5.
我院西门子ＳＯＭＡＴＯＭ ＣＲ型ＣＴ扫描使用的ＯＰＴＩ－１５１型管球自１９９１－１１月至１９９５－１０月，四年时间城，爆光次数达３１．８万多次，次数很多，本文介绍了延长ＣＴ管球使用寿命的方法。 相似文献
6.
李建平 《CT理论与应用研究》1996,5(2):25-29
本文介绍了采用中国推广普及型ＣＴ，根据世界卫生组织提出的ＱＡ、ＱＣ体系的原则，制定中型医院ＣＴ室“ＣＴ室组织行为规范”，“ＣＴ扫描技术规范”；“ＣＴ诊断技术规范”。 相似文献
7.
本文目的,通过将ＧＤ－ＤＴＰＡ直接注入蛛网膜下腔后进行脊髓造影ＭＲ扫描,探索一种新的ＭＲ检查方法,材料方法：对１１例患者进行ＧＤ－ＤＴＰＡ蛛网膜腔直接注射脊髓造影前后ＭＲ扫描,保持扫描序列不变。造影剂量为０．５～１．０ｍｌ,结果：所有患者脊髓造影后即刻扫描显示脑脊液信号反转,Ｔ１Ｗ高信号。Ｔ２Ｗ低信与,结论：小剂量ＧＤ－ＤＴＰＡ直接蛛网膜注射脊髓造影ＭＲ扫描是一种安全可靠的检查方法。对观察脑脊液动 相似文献
8.
急性颈椎损伤的CT诊断 总被引：2，自引：1，他引：1
本文目的是分析急性颈椎损伤（ＡＣＴ）的ＣＴ征象,评价ＣＴ在ＡＣＴ诊断中的价值及限度。方法：７８例颈椎外伤患者行平片、薄层ＣＴ检查及三维重建,并做对照分析。结果经影像学诊断６０例ＡＣＴ,ＣＴ诊断５９例,１例ＣＴ阴性而由平片确诊 １例。平片与ＣＴ的骨折检出率分别为 ５３． ３％和 ９８．３％。结论：ＣＴ比Ｘ线平片可发现更多的骨折,并能明确骨折块与椎管的关系。这对临床处理严重颈椎损伤起到指导作用。 相似文献
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10.
评价高分辨率ＣＴ（ＨＲＣＴ）扫描在运气了管扩张诊断中的应用价值。分析１９例支气管扩张的ＨＲＣＴ表现并与Ｘ线平电及常规ＣＴ扫描进行比较。本组柱状支气管扩张占６３．６％，静脉曲张型支气管扩张占２６．３２％，囊状支气管扩张占１０．５２％，扩张的支气管管壁厚度在１－３ｍｍ之间。ＨＲＣＴ扫描是诊断支气管扩张最安全，准确，可靠的方法之一。 相似文献
11.
Todd H. Skaggs 《Advances in water resources》2011,34(10):1335-1342
Critical path analysis (CPA) is a method for estimating macroscopic transport coefficients of heterogeneous materials that are highly disordered at the micro-scale. Developed originally to model conduction in semiconductors, numerous researchers have noted that CPA might also have relevance to flow and transport processes in porous media. However, the results of several numerical investigations of critical path analysis on pore network models raise questions about the applicability of CPA to porous media. Among other things, these studies found that (i) in well-connected 3D networks, CPA predictions were inaccurate and became worse when heterogeneity was increased; and (ii) CPA could not fully explain the transport properties of 2D networks. To better understand the applicability of CPA to porous media, we made numerical computations of permeability and electrical conductivity on 2D and 3D networks with differing pore-size distributions and geometries. A new CPA model for the relationship between the permeability and electrical conductivity was found to be in good agreement with numerical data, and to be a significant improvement over a classical CPA model. In sufficiently disordered 3D networks, the new CPA prediction was within ±20% of the true value, and was nearly optimal in terms of minimizing the squared prediction errors across differing network configurations. The agreement of CPA predictions with 2D network computations was similarly good, although 2D networks are in general not well-suited for evaluating CPA. Numerical transport coefficients derived for regular 3D networks of slit-shaped pores were found to be in better agreement with experimental data from rock samples than were coefficients derived for networks of cylindrical pores. 相似文献
12.
A thin-walled steel tube/bamboo plywood composite hollow column with binding bars (SBCCB) was developed using transverse binding bars to reinforce a thin-walled steel tube and bamboo plywood composite hollow column. Low reversed cyclic loading tests were performed on 9 SBCCB specimens to observe the damage process and morphology in the SBCCBs. The effects of the slenderness ratio, the net cross-sectional area of the bamboo plywood, the assembly patterns of the cross sections, and the binding bars on the stress and seismic performance were investigated. The results show that the main failure modes of the SBCCBs were cracking of different adhesion interfaces at the base of the column and fracturing of the bamboo plywood. The cross-sectional assembly pattern has a significant effect on the failure modes; increasing the cross-sectional area and the slenderness ratio of the composite column will dramatically improve the seismic performance of the SBCCBs. SBCCBs have excellent elastic deformation and seismic energy consumption characteristics. The binding bars ensure the integrity of the specimen and inhibit the failure of the adhesion interface at the base of the column. Finally, based on the measurement of the axial pressure and the stress-strain curve within elastic range of the composite columns, a simplified mechanical model and a calculation method for bearing capacity was formulated. The calculation values of bearing capacity agree well with the experimental ones, and calculation method can be used to provide guidance for engineering applications of a SBCCB. 相似文献
13.
目的：探讨CT动脉增强分数（AEF）与肝癌经导管动脉化疗栓塞（TACE）治疗效果的相关性。方法：对我院2019年1月至2020年1月43例原发性肝细胞癌（HCC）患者临床资料进行回顾性分析,所有患者均接受TACE治疗,术前及术后1个月均行CT动态增强扫描检查,根据治疗效果分为治疗有效组及无效组,采用电化学发光法检测各组甲胎蛋白（AFP）水平,比较两组治疗前后AEF、AFP、肿瘤大小变化;采用Pearson系数探究AEF、AFP与肿瘤大小变化的相关性,采用受试者工作特征曲线（ROC）及曲线下面积（AUC）分析肝脏动态增强扫描联合AEF彩图对TACE疗效的评估价值。结果：有效组治疗后AEF、AFP、肿瘤大小均小于治疗前、无效组;Pearson相关性分析结果显示,TACE治疗后AEF、AFP均与肿瘤大小呈正相关;ROC曲线分析结果显示,肝脏动态增强扫描联合AEF评估TACE疗效的AUC为0.902,明显高于肝脏动态增强扫描及AEF单独评估的0.793和0.771。结论：AEF对TACE治疗效果具有良好的评估价值,联合肝脏动态增强扫描能进一步提高准确度,可作为TACE治疗HCC疗效评估的辅助手... 相似文献
14.
目的:探讨3种不同肠道准备方法在CT小肠造影（CTE）中的应用价值。方法:对156例临床怀疑为小肠病变而行CTE的病例进行前瞻性研究。156例随机分为A、B和C组各52例,肠道造影剂均采用口服法。A和B两组在扫描前16h进食半流质饮食,并均以番泻叶6g导泄,扫描前12h禁食,扫描前1h起每隔15min A组尽量口服等渗甘露醇、B组同法尽量口服引用水。C组扫描前6h禁食,扫描前1h起每隔15min尽量口服饮用水。3组均在口服对比剂10min后进行CTE检查。统计比较3组小肠的充盈效果及对小肠病变的诊断价值。结果:小肠充盈效果比较A组最佳,B组次之,C组最差;对小肠病变的诊断结果显示A组对小肠各段病变的诊断价值均较显著;B组对十二指肠、空肠病变诊断价值较大,对回肠的细小病变诊断效果较差;C组对十二指肠及空肠上段病变诊断效果较好,但不利于空肠上段以远细小病变的诊断。结论:充分的肠道准备是CTE的重要技术因素,分次口服等渗甘露醇尽量充盈小肠有利于小肠病变的显示,是一种安全可靠、经济方便的肠道准备方法。 相似文献
15.
Confocal scanning light microscopy is a valuable new method for examining the nature and progress of stone weathering at a level of resolution between optical microscopy and scanning electron microscopy. Not only is it non-destructive, but it can also create three-dimensional images. 相似文献
16.
目的：探讨多层螺旋CT（MSCT）增强扫描对颈部神经鞘瘤的诊断价值。方法：对经手术病理证实的20例颈部神经鞘瘤患者的CT图片进行回顾性分析,分别在轴位、二维图像上观察神经鞘瘤肿块的CT表现。结果：18例肿块位于颈动脉间隙内,1例位于颈后区,1例位于腮腺区。CT平扫表现为不均匀等低密度肿块18例,均匀等密度肿块2例;增强后18例早期不均匀强化、延迟扫描呈渐进性强化,2例强化均匀;18例有不同程度的血管推移征。结论：MSCT增强扫描对颈部神经鞘瘤能准确定位,清晰显示肿块与邻近血管等重要结构的解剖关系,延迟后渐进性强化及颈动脉间隙血管移位征象有很高的定性诊断价值,对临床诊断和手术治疗具有重要的指导意义。 相似文献
17.
目的:探讨多房囊性肾细胞癌(MCRCC)的256层iCT增强扫描影像特征。方法:搜集6例经外科手术病理证实为多房囊性肾细胞癌患者的临床资料、CT影像资料及病理资料,对比分析多房囊性肾细胞癌的影像特点。结果:6例均发生于肾实质区,增强扫描可见不同程度囊性改变、无明显壁结节、有包膜边界清晰、肾盂肾盏无侵蚀破坏,无肾静脉癌栓形成,均无远处转移征象,3例行患侧肾全切除术,3例行肾肿瘤楔形切除术。结论:多房囊性肾细胞癌的256层iCT增强扫描表现有一定特征性,可作为术前诊断的理想手段,对治疗方案的优选及改善患者生存质量有积极意义。 相似文献
18.
G. Jayachandran M.M. Abdul RazakA.G.V. Prasad E. Unnikrishnan 《Physics of the Earth and Planetary Interiors》2003,138(2):131-145
The devastating earthquake on 26 January 2001 at Bhuj, India, resulted in large-scale death and destruction of properties of several million US dollars. The moment magnitude of the earthquake was 7.7 and its maximum focal intensity exceeded X in MM scale. The rate of aftershocks of this earthquake, recorded at Gauribidanur seismic array station (GBA), shows a monotonic decay with time superposed with oscillations. For the Indian continent the Lg phase is a prominent arrival at regional distances. The estimate of Lg amplitude is obtained by optimally fitting the Lg wave train to a exponential decay curve. The logarithm of these amplitudes and logarithm of root mean square (rms) value of actual amplitudes of the Lg are calibrated with USGS mb to create a local mbLg magnitude scale. The energy released from these aftershocks is calculated from the rms value of Lg phase. The plot of cumulative energy release with time follows the power law of the form tp, superposed with oscillations. The exponent of the power law, p, is estimated both by a time-window scanning method and by an interpolation method. The value of p is 0.434 for time-window scanning method and 0.432 for the interpolation method. The predominant periods found in the oscillatory part of the cumulative energy, obtained by differencing the observed from the power law fit, are 10.6, 7.9, 5.4, 4.6 and 3.5 h for time-window scanning method. The corresponding periods for interpolation method are 13.4, 11.5, 7.4, 4.2, 3.5, 2.6 and 2.4 h. 相似文献
19.
An improved resonant fluorescence instrument for measuring atomic oxygen concentration was developed to avoid the Doppler effect and the aerodynamic shock effect due to the supersonic motion of a rocket. The shock effect is reduced by adopting a sharp wedge-shaped housing and by scanning of the detector field of view to change the distance between the scattering volume and the surface of the housing. The scanning enables us to determine absolute values of atomic oxygen concentration from relative variation of the scattered light signal due to the self-absorption. The instrument was calibrated in the laboratory, and the numerical simulation reproduced the calibration result. Using the instrument, the altitude profile of atomic oxygen concentration was observed by a rocket experiment at Uchinoura (31°N) on 28 January 1992. The data obtained from the rocket experiment were not perfectly free from the shock effect, but errors due to the effect were reduced by the data analysis procedure. The observed maximum concentration was 3.8× 1011 cm−3 at altitudes around 94 km. The systematic error is estimated to be less than ±0.7×1011 cm−3 and the relative random error is less than±0.07× 1011 cm−3at the same altitudes. The altitude profile of the OI 557.7-nm airglow was also observed in the same rocket experiment. The maximum volume emission rate was found to be 150 photons cm−3 s−1 at 94 km. The observed altitude profiles are compared with the MSIS model and other in situ observations. 相似文献
20.
Magnetic minerals are mostly identified by a combination of rock magnetic and microscopic techniques and the ferrofluid method in combination with an optical microscope was applied during the last decades. But today, scanning electron microscopy (SEM) is preferred for the observation of mineral phases because its depth of focus and resolving capability at the same magnification. In this study, we report on a method, which allows ferrofluid application under the SEM. We coated a polished basalt sample containing titanomagnetite grains with high demagnetizing fields, with a colloidal suspension containing magnetite particles (ferrofluid) ranging in size between 11 and 20 nm. Due to large gradients of multidomain grains the ferrofluid particles adhered to their surfaces. Other grains of similar composition present (ilmenohematite) but with low demagnetizing fields do not generate large magnetic gradients and therefore do not attract the colloidal particles. Upon evaporation of the ferrofluid and covering the sample with conducting material the magnetic grains with high demagnetizing field are easily identifiable under the scanning electron microscope. The different mineralogy observed by this method is confirmed by temperature dependent variation of magnetic susceptibility, revealing titanomagnetite and ilmenohematite as magnetic carriers in the basaltic samples. 相似文献