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991.
Three illustrative cases of magnetic resonance imaging (MRI) in patients with perianal Crohn's disease are presented. Modern MRI techniques provided excellent visualization of perineal anatomy, inflammatory tissues and an anorectal stricture. It also allowed detailed delineation of the patho-anatomy of fistulous abscess and any communication to more proximal bowel. This report illustrates the potential of modern MRI as an important investigative adjunct in evaluating the anorectal manifestations of Crohn's disease. 相似文献
992.
应用多普勒组织成像评价肥厚型心肌病左室收缩功能 总被引:4,自引:0,他引:4
目的 :应用多普勒组织成像脉冲速度模式测量二尖瓣环收缩速度 ,以评价肥厚型心肌病患者左室收缩功能的改变。材料和方法 :对肥厚型心肌病及正常人分别测量二尖瓣环各点收缩期峰值速度。结果 :肥厚型心肌病患者与正常组二尖瓣环收缩期峰值速度有显著性差异 ,均较正常组减低。结论 :肥厚型心肌病患者左室长轴收缩功能减低。 相似文献
993.
CHRISTIANE MENDRE VERONIQUE SARRADE BERNARD CALAS 《Chemical biology & drug design》1992,39(3):278-284
The continuous flow syntheses of endothelin 1, proendothelin 2. ATP binding site of the CDC2 kinase 3, and fragment 18-30 of an actin 4, have been performed by using a polyacrylamide gel resin Expansin? (about 0.6 mmol NH2/g) with the glycolamidic ester handle as labile anchorage. In addition, we report here a method of air oxidation which reduces the formation of side-products related to the formation of intermolecular disulfide bridges. 相似文献
994.
肝脏螺旋CT动态增强扫描时肝动脉期肝实质一过性异常强化的研究 总被引:26,自引:1,他引:25
目的 研究肝脏螺旋CT动态增强扫描时肝动脉期肝实质一过性异常强化 (transienthepaticabnormalenhancement,THAE)的表现特征 ,探讨其产生原因及临床意义。方法 1999年 1月至2 0 0 1年 9月 92 6例患者因各种原因接受了肝脏或上腹部螺旋CT扫描。CT扫描常规先作全肝或上腹部螺旋CT平扫 ;注射对比剂开始后 2 5~ 3 0s行肝动脉期扫描 ,65~ 70s行门静脉期扫描 ;对部分病例还行病灶局部延迟扫描 ,延迟时间为 3、5及 10~ 15min。肝动脉期共检出 82例 (男 72例 ,女 10例 ;年龄 2 6~ 78岁 )具有THAE ,着重对其在平扫和增强各期图像上的表现、与肝内或肝外病灶的关系以及门静脉系统情况做详细观察和记录。结果 82例 (8 9% )共有 12 2处肝动脉期THAE ,其中 110处(90 2 % )平扫未显示THAE区域密度异常 ,12处 (9 8% )呈稍低密度 ;所有 12 2处THAE在肝动脉期都为均匀的高密度影 ;在门静脉期 ,10 9处 (89 3 % )转为等密度而不能分辨 ,余 13处 (10 7% )为均匀稍高密度影 (其中 10处作了延迟扫描 ,均转为等密度 )。 83处 (68 0 % )THAE呈边缘光滑的楔形或扇形 ,2 9处呈不规则形 (2 3 8% ) ,余为其他形状。THAE紧贴肝内肿瘤或其他病灶的有 46处 (3 7 7% ) ,邻近肝外肿瘤或其他病灶 2 0处 (16 4% ) ,余 5 6处 (45 相似文献
995.
W. H. M. Castro H. Halm J. Jerosch J. Steinbeck M. Meyer K. H. Gohlke J. Assheuer 《European spine journal》1994,3(4):222-224
Summary After treatment of a symptomatic herniated disc with chymopapain, 14 patients were re-examined by magnetic resonance imaging (MRI) at a mean follow-up of 72 months. Well-defined MRI findings before chemonucleolysis were compared with those after the procedure by an independent observer. Five MRI parameters were assessed. No significant change was noted in the signal intensity of the affected disc, the extent of osteochondrosis and endplate reaction of the affected segment. The height of the affected disc as well as the size of the disc herniation were reduced significantly. The loss of the height is seen as a direct result of chymopapain activity, whereas the alteration of the size of the herniation seems to depend on the natural history of a disc herniation and is probably not a simple result of the treatment. 相似文献
996.
Masahiko Kawaguchi Masakazu Kuro Hisatoshi Ohsumi Toshito Nakajima Yoshihiro Kuriyama Jun Karasawa 《Journal of anesthesia》1994,8(1):60-63
We assessed the local cerebral blood flow (LCBF) in 40 patients under fentanyl-diazepam anesthesia. The measurement of LCBF
was made using 50%–70% stable xenon with 20 min of inhalation interval and a shuttle method for computed tomography imaging.
All patients were anesthetized with 5.95±1.76 μg·kg−1 fentanyl and 0.22±0.07 mg·kg−1 diazepam under mechanical ventilation during CBF measurement. The values and distribution of LCBF on non-affected hemisphere
appeared to be unaltered by fentanyldiazepam anesthesia. We also assessed the cerebral carbon dioxide reactivity in 6 patients.
The cerebral carbon dioxide reactivity, expressed as percentage change in LCBF per unit change in arterial carbon dioxide
partial pressure, was 5.39±1.07, and there were no significant differences of reactivity among regions studied. In conclusion,
we showed reference values of LCBF and carbon dioxide reactivity, measured by stable xenon-enhanced computed tomography, in
patients under fentanyl-diazepam anesthesia. Carbon dioxide reactivity was preserved in all regions including gray matter,
white matter, and basal ganglia. 相似文献
997.
998.
999.
高效液相色谱法测定微量耳血中头孢他定的浓度 总被引:2,自引:0,他引:2
本文介绍采取微量耳血以高效液相色谱法测定头孢他定(Ceftazidime)的血药浓度。血样经6%高氯酸沉淀蛋白,流动相为含25%甲醇的0.05mol/L醋酸铵溶液,以冰醋酸调节pH值至4~5,检测波长为254nm,内标物为头孢唑啉(Cefazolin)。经对家兔采取微量耳血测定其血药浓度,可知头孢他定为二室模型,T_1/2α为0.18±0.05h,T_1/2β为1.75±0.07h。并对3名住院病人静脉注射1g头孢他定后定时分别取微量耳血进行分析,所得结果与文献基本一致。本文方法简便、快速,结果令人满意。 相似文献
1000.
MRI and SPECT findings in amyotrophic lateral sclerosis 总被引:1,自引:0,他引:1
Summary MRI was performed in 21 patients and single photon emission computed tomography (SPECT) withN-isopropyl-p-123I iodoamphetamine in 16 patients, to visualize upper motor neurone lesions in amyotrophic lateral sclerosis. T2-weighted MRI revealed high signal along the course of the pyramidal tract in the internal capsule and cerebral peduncle in 4 of 21 patients. SPECT images were normal in 4 patients, but uptake was reduced in the cerebral cortex that includes the motor area in 11. 相似文献