胃间质瘤的影像学诊断

胃间质瘤(gastric stromal tumor,GST)是一种较少见的独立起源于胃肠道原始间叶组织的非定向分化的肿瘤,属于消化道间叶性肿瘤[1]。本文报告经手术、病理和免疫组织化学检测9例GST的影像学表现,并探讨其影像学检查的诊断价值。1材料与方法1.1一般资料本组男5例,女4例,年龄43~70岁,平均52岁。临床表现上腹部不适、胀痛、乏力和纳差9例,恶心呕吐5例,黑便3例,消瘦、便秘2例,胃手术史1例。病程1~6个月。查体腹部触及包块6例。1.2方法9例行B超检查,8例行上消化道造影检查,6例行螺旋CT平扫和增强扫描,2例行MRI平扫和增强扫描。手术9例均行光…     

In vitro metabolism and toxicity assessment of toxin T-514 (Peroxisomicine A1) of Karwinskia humboldtiana in microsomes and primary cultured hepatocytes.

T-514 (Peroxisomicine A(1)) from Karwinskia humboldtiana is a dimeric hydroxyanthracenone with a highly selective cytotoxic effect on tumor cells. We evaluated the metabolism of this compound in two in vitro systems (liver microsomes and hepatocytes) and assessed the cytotoxicity of its metabolites on normal and tumor cells. Microsomes (12.5, 125 and 250 microg of protein/ml) and hepatocytes (1 x 10(6) cells/ml) were incubated with the toxin (25 microM) for 0.5, 1, 3, 6, 9, 12 and 24 h and the samples were examined using chromatographic analysis and UV spectra. Two metabolites (M1 and M2) were detected in the rat microsomes and one (M1) in the monkey microsomes. The retention times and UV spectra of the peaks were very similar to those of the toxin T-514. M1 was isolated and identified as a mixture of two isomers. The cytotoxicity of the metabolites was evaluated in Chang liver and Hep G2 cells but they did not show the selective cytotoxic effect on tumor cells seen in the original compound.     

Vascular Centerline Extraction in 3D MR Angiograms for Phase Contrast MRI Blood Flow Measurement

The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction, multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients, by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries. In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively. In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery. Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA.     

罗比卡因与布比卡因硬膜外麻醉剖宫产术时心电图及心肌酶的变化

目的　比较硬膜外麻醉剖宫产术时罗比卡因和布比卡因对心电图及心肌酶的影响。方法　择期剖宫产手术病人 30例 ,硬膜外麻醉时Ⅰ组 (15例 )用 0 5 %罗比卡因 ,Ⅱ组 (15例 )用0 5 %布比卡因。观察麻醉手术期间心电图P R、QRS波间期以及肌酸磷酸激酶 (CK)和同工酶 (CK MB)的变化 ,同时观察麻醉镇痛、肌松效果和不良反应。结果　两组病人P R、QRS波间期均在正常范围内 (P >0 0 5 )。两组病人CK术后 2 4h值明显高于术前 (P <0 0 5 ) ,但反映心肌受损特异性较高的CK MB则无明显变化 (P >0 0 5 ) ,两组间亦无差异 (P >0 0 5 )。麻醉效果及不良反应两组间无差异。结论　硬膜外麻醉时罗比卡因与布比卡因对心电图及心肌酶影响无明显差异     

神经导航在经蝶显微切除侵袭性鞍区肿瘤手术中的应用

目的 评价神经导航技术在经蝶显微切除侵袭性鞍区肿瘤手术中的应用价值。方法 在18例经蝶手术中，应用Stealstation神经导航系统指导手术，明确手术方向、肿瘤边界、肿瘤切除程度。术后均通过MRI验证肿瘤切除率。结果 18例肿瘤中，全切除或次全切除14例，大部分切除4例，均无严重术后并发症。结论 应用神经导航技术能扩大经蝶显微手术适应证，提高侵袭性鞍区肿瘤的切除率，减少手术并发症。