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排序方式: 共有2809条查询结果,搜索用时 15 毫秒
1.
目的探讨宝石CT碘-水基图在急性脑梗死介入治疗后的诊断价值。方法 31例急性脑梗死患者介入治疗后即刻宝石CT平扫QC图发现颅内异常高密度影,采用碘-水基图进行重建分析,同时测定高密度影碘基值、水基值,并与术后24 h普通CT复查诊断结果作比较。结果通过采用碘-水基图,17例诊断为碘对比剂渗出,14例诊断为脑出血转化,与术后24 h普通CT复查诊断结果完全一致(Kappa=1,P0.01);术后即刻碘基图之碘基值:碘对比剂渗出(32.09±5.36) g/L,脑出血转化(6.86±2.26) g/L,二者差异有统计学意义(t=53.291,P0.01);术后即刻水基图之水基值:碘对比剂渗出(1 027.93±8.29) g/L,脑出血转化(1 069.68±7.18) g/L,二者差异有统计学意义(t=-8.897,P0.01)。结论宝石CT碘-水基图可以准确诊断急性脑梗死介入治疗后颅内碘对比剂渗出和脑出血转化,值得向临床介绍推广。 相似文献
2.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
3.
目的:建立侧向发育型肿瘤细胞(LST)株双向电泳技术.方法:提取LST细胞株总蛋白质,采用不同pH范围IPG胶条进行LST细胞株总蛋白质双向电泳,并对实验步骤进行一系列的调整优化.结果:获得了较为清晰的LST细胞株双向电泳图谱,采用pH 3~10线性IPG胶条分离出1356±43个蛋白质斑点;pH 4~7 IPG胶条两种上样量(250μg和150μg)分别分离出了1285±51和989个蛋白质斑点.结论:通过相关条件的调整优化,成功建立了双向电泳技术,为研究LST特殊性生物学行为相关蛋白质奠定了坚实的基础. 相似文献
4.
李阳春 《南通大学学报(哲学社会科学版)》2002,18(2):117-120
八十年代初中期 ,中国戏剧积极拓展我国传统戏剧的时空观、写意性特征 ,大胆借鉴西方现代戏剧的荒诞化、意象性技巧 ,出现了探索创新、多元发展的崭新局面。其中对“三一律、一堵墙”戏剧观的突破 ,运用意识形象外显人物的内心世界 ,嫁接多种艺术手段将现实时空转化为艺术时空 ,是新时期戏剧艺术探索最突出的三项成就。而过分强调形式技巧 ,脱离观众欣赏习惯 ,致使演出市场萎缩 ,观众锐减 ,无疑是新时期戏剧艺术探索中面临的最大困顿。 相似文献
5.
人大肠癌不同转移潜能细胞株SW620及SW480的差异蛋白质组分析 总被引:2,自引:0,他引:2
6.
Familial homozygous hypercholesterolemia: clinical and cardiovascular features in 18 patients 总被引:2,自引:0,他引:2
G J Brook S Keidar M Boulos E Grenadier A Wiener N Shehada W Markiewicz A Benderli M Aviram 《Clinical cardiology》1989,12(6):333-338
Homozygous familial hypercholesterolemia (HFH) is a very rare autosomal dominant disease characterized by accelerated severe atherosclerosis. We examined 18 patients from 9 families with HFH. The age range was 6-30 years (mean = 16 years). Male to female ratio was equal. All patients had huge, multiple tuberous xanthomas on the skin and tendons. Mean +/- standard deviation of plasma cholesterol, triglycerides, low-density lipoproteins (LDL), and high-density lipoproteins (HDL) cholesterol levels were 608 +/- 89, 122 +/- 39, 550 +/- 88, and 26 +/- 8 mg/dl, respectively. Five patients (28%) had angina pectoris, two sustained a myocardial infarction, and one died at the age of 15 years. Two-dimensional echocardiography demonstrated supravalvular aortic stenosis in 3 of the 13 patients (23%). Coronary arteriography performed in 11 patients demonstrated significant obstruction in 6 patients, 2 each with single-, double-, and triple-vessel disease. Left main stenosis was present in 3 patients (27%). Supravalvular aortic narrowing was demonstrated in 6 patients (54%) and was associated with a gradient in 2 (25 and 35 mmHg, respectively). Segmental contraction abnormalities were detected in 2 of the 11 patients (18%). It is concluded that coronary artery disease is prevalent in patients with HFH and, based on the data presented, we recommend the performance of noninvasive technique, coronary arteriography and supravalvular aortography at an early age to detect and to follow the progression of the disease. 相似文献
7.
Objective To explore the effect of L-canosine in preventing and treating rat cataract induced by sodium selenite. Methods This was an experimental study. Cataract was induced in the rats by sodium selenite. Rats were divided into 3 groups and each group has 3 ones. L-canosine eye drops (50 g/L or 20 g/L) and 0.9% normal saline were respectively instilled to the rat eye for 3 weeks and examined. L-canosine was added to the medium of cultured rat cataract lens at 1.00, 0.10 and 0.01 g/L for 1 week and then examined. Cataract lens were studied by using two-dimensional eletrophoresis. Results One week after instillation of L-canosine, the scores of rat cataract were 2.22±0.65, 2.39±0.98 and 2.83±0.38 in 50 g/L, 20 g/L L-canosine and control groups, respectively. The lesion in 50 g/l, L-canosine group was lighter than that of the control group. There was significant difference between these two groups (P=0.013). On the 2nd and 3rd weeks, there was no difference among these three groups. After 1 week for culturing cataract lens, there was no difference between these three groups. The results of two-dimensional eletrophoresis showed that the protein number was 182 and 161 in the L-carnosine and control groups, respectively. High molecular weight protein decreased and low molecular weight protein increased in L-carnosine group. Conclusions L-carnosine at 50 g/L could restrain the development of early stage rat cataract. L-camosine could modulate the rat lens protein in vitro, but could not affect lens cataract scores. 相似文献
8.
Eric K. Outwater Katsuyoshi Ito Evan Siegelman C. Edwin Martin Manoj Bhatia Donald G. Mitchell 《Journal of magnetic resonance imaging : JMRI》1997,7(6):1033-1039
The purpose of this study is to describe a subset of atypical hepatic hemangiomas that enhance rapidly and diffusely and to determine whether heavily T2-weighted images could distinguish between atypically enhancing liver hemangiomas and hypervascular malignancies. A retrospective search of MR records identified seven patients with liver hemangiomas that demonstrated diffuse early enhancement and 23 patients with biopsy-proven malignant liver lesions that were hypervascular on dynamic gadolinium-enhanced MR images. Quantitative analysis of signal intensity measurements was performed on the T2-weighted images, heavily T2-weighted (TE < 140), and dynamic gadolinium-enhanced images. Blinded reader comparison of the T2-weighted images and gadolinium-enhanced images was performed. Hypervascular hemangiomas enhanced to a greater degree than hypervascular malignant liver lesions on the early phase gadolinium-enhanced images. Perilesional parenchymal enhancement was demonstrated in five cases of rapidly enhancing hemangiomas. Signal intensity and contrast-to-noise ratios on the heavily T2-weighted images of the hemangiomas were significantly greater than that of the hypervascular malignant lesions (P < .05). Hemangiomas were differentiated from the hypervascular malignant liver lesions with high accuracy (97–100%) by three blinded readers based on the T2-weighted images. A subset of hemangiomas have atypical rapid diffuse enhancement on dynamic gadolinium-enhanced images. These atypical hemangiomas can be distinguished from hypervascular malignant liver lesions on T2-weighted MR images. 相似文献
9.
10.
颅面部的 CT扫描检查主要包括颅脑面部上、下颌骨、中耳、内耳、鼻窦、眼眍、眼球及颞骨茎突等部位的扫描检查 ,上述部位的扫描检查的位置的摆法 ,层面的厚度、间距 ,扫描时间及螺距等参数的选择及扫描后图像的后处理工作对检查结果的诊断至关重要。上述参数任意一个选择不当及 相似文献