多层螺旋CTA:不同重建方法在主动脉瘤腔内隔绝术后的应用评价

目的：探讨多层螺旋CT血管造影不同重建方法在主动脉瘤腔内隔绝术后的临床应用价值。材料与方法：46例主动脉瘤腔内隔绝术后行多层螺旋CT血管造影，采用准直2.5mm，层厚3.0mm，螺距为6，重建方法为容积显示技术（volume rendering，VR）、表面阴影遮盖显示(shade surface display，SSD)及最大密度投影法（maximum intensity projection，MIP），并对三种方法进行比较。结果：46例中有1例术后内支架出现局限性断裂，VR及MIP均清晰显示了内支架的变化，SSD未能显示。1例内支架展开不良，三种重建方法均明确显示；6例术后出现渗漏，VR清晰显示渗漏的部位、形态及内漏量，MIP、SSD仅显示其中的5例，三者中以VR显示最佳。在显示支架内血流情况及瘤周血栓方面，VR能明确支架内有无血栓形成及腔内隔绝术后的转归变化，VR显示1例术后支架内血栓形成SSD及MIP未能显示。结论：多层螺旋CT能在较短时间内进行大范围的扫描，有利于主动脉病变的检查；VR图像优于SSD及MIP，能为术后内支架情况提供更多更准确的信息，VR技术应作为主动脉瘤内支架术后的首选三维重建方法。     

实验性小肠动脉出血的垂体后叶素灌注治疗

经动脉导管灌注垂体后叶素治疗１０条犬小肠出血的实验研究结果表明，垂体后叶素灌注治疗的效果与出血部位累及的血管大小及出血速率有关。还提示垂体后叶素对较大血管引起的出血灌注治疗无效，其引起血管的收缩作用主要在末梢小血管。     

The anterior choroidal artery syndrome

We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit.     

缺血性脑血管病的MRA诊断

目的:评价磁共振血管成像(MRA)对诊断缺血性脑血管病的能力和意义。材料和方法:分析109例经临床及CT、MRI诊断为缺血性脑血管病患者的MRA影像。使用1.0T超导磁共振机,在常规T_1、T_2加权成像后,用三维TOF法以willis环为中心进行轴位成像。结果:MRA能较为清晰地显示颈内动脉、椎、基底动脉、大脑前、中、后动脉主干的中度以上狭窄或闭塞。109例患者中共显示动脉狭窄75支,动脉闭塞108支,均与梗塞区域及临床症状相符合。结论:MRA对脑动脉的显示具有清晰、准确、对比度好、绝大多数(82％)无伪影等优点。与MRI结合使用,能更为准确地判定缺血性脑血管病的类型、范围及程度。     

Relationship between renal capsular artery feeding and size of VX-2 carcinoma implant in the rabbit kidney

When regional intraarterial infusion is applied in the treatment of malignant tumors it is essential to reach the tumor via all its major feeder vessels. In this study VX-2 carcinoma was implanted into the lower pole of the left kidney in 24 rabbits to investigate whether the renal capsular artery takes part in tumor feeding. The rabbits were divided into four groups that were followed for 8, 10, 12 or 14 days after tumor implantation. At that time the renal artery was ligated close to the kidney and subsequently silicone rubber or barium sulfate/gelatin suspension was injected into the capsular artery. The tissue was cleared, and the tumor carefully removed and examined microscopically for traces of silicone rubber. When barium sulfate had been injected, the kidney was examined radiographically in order to detect possible presence of contrast medium in the tumor. This study revealed no vascular supply to the implanted VX-2 carcinoma from the capsular artery when the tumor was confined intracapsularly, i.e., up to 12 days after tumor implantation in untreated rabbits.This investigation was performed at the Oncological Research Laboratory, Department of Diagnostic Radiology, University of Bergen, Bergen, Norway     

MSCT支气管动脉三维成像对中心型肺癌的血供研究

目的：探讨多层螺旋CT(MSCT)三维支气管动脉成像在中心型肺癌中的影像学表现．为显示中心型肺癌的血供来源及介入治疗提供理论依据。方法：对18例中心型肺癌的患者行MSCT造影增强检查，采用实时螺旋薄层CT扫描，在独立工作站行支气管动脉三维重建，使用不同的旋转轴观察支气管动脉的空间解剖细节。结果：其中6例(33．33％)中心型肺癌的支气管动脉三维图像能够清晰显示出支气管动脉的起源、走行的路径(肺内段和纵隔段)和血管直径等。有肺动脉明显狭窄截断的病例支气管动脉显示率最高，且明显增粗，表明此类肺癌的血供来源主要以支气管动脉为主。三维成像中以容积再现(VR)技术显示最佳。结论：MscT三维支气管动脉成像能够准确、直观地显示支气管动脉的空间解剖特点，为中心型肺癌的血供研究及介入治疗提供理论基础。     

An Historical Perspective from the Green Revolution to the Gene Revolution

Since the 1960s conventional crop breeding has increased food production commesurate with the growing population. For agricultural development to continue, the exploitation of greater genetic diversity and modern biotechnology are becoming increasingly important. This article reviews the milestones achieved by the Green Revolution and many of the recent breakthroughs of modern biotechnology.     

肺癌侵犯中央肺动脉继发肺低灌注的CT与DSA对照研究

目的　探讨肺癌侵犯中央肺动脉继发肺低灌注的CT特征及其诊断价值。方法　对2 0例手术及病理证实的肺癌侵犯中央肺动脉 (cancerousinvasionofcentralpulmonaryarteriesinlungcancer,CICPA)患者术前肺血管DSA及增强螺旋CT(含高分辨率CT ,即HRCT)征象行前瞻性对照研究。根据DSA和CT胸膜下末梢肺动脉分布和数量变化 ,即肺血管征、肺毛细血管充盈度和肺实质强化后密度及时间 密度曲线变化 (即肺实质征 ) ,行两者间的盲法对照 ,统计学分析CT与DSA征象及其一致性 ,评估CT对CICPA继发肺低灌注的诊断价值。结果　 2 0例手术病理证实的CICPA病例中 ,共3 0支肺叶动脉受累 ,DSA显示 90 % (2 7/3 0 )出现肺叶低灌注征象 ,CT诊断肺低灌注敏感度为 78%(2 1/2 7) ,特异度 10 0 % (3 /3 ) ,准确度 80 % (2 4/3 0 )。肺低灌注与CPA狭窄程度无明显相关性 (rs=0 40 ,P =0 0 73 )。CT与DSA的肺血管征一致性较好 (Kappa =0 69,P <0 0 0 1) ,而肺实质征一致性稍差 (Kappa =0 3 7,P =0 0 11)。结论　肺低灌注是肺癌侵犯中央肺动脉的常见表现 ,CT对其定性诊断具有重要价值 ,而定量判断有一定限度     

Does Quality Improvement Work? Evaluation of the Organ Donation Breakthrough Collaborative

Objective. The Organ Donation Breakthrough Collaborative is a quality improvement initiative to encourage adoption of "best practices" for identifying potential donors and obtaining consent for deceased organ donation. We evaluate the impact of the first phase on organ donation rates.
Setting. We study donation rates in the 95 hospitals that participated in the first phase and a control group of 125 hospitals.
Design. We use a controlled pre/post design. The preperiod is the year before the start of the Collaborative (September 2002 to August 2003), the postperiod is the final 6 months of the first phase (March 2004 to August 2004).
Data. We use administrative data from the Organ Procurement and Transplantation Network to compute the conversion rate in each hospital group and time period. The conversion rate is the proportion of eligible donors who became actual donors.
Principal Findings. Preperiod conversion rates in Collaborative and control hospitals were similar: 52 and 51 percent, respectively. In the postperiod, the conversion rate increased to 60 percent among Collaborative hospitals and remained at 51 percent among control hospitals. The relative change was 8 percentage points (95 percent confidence interval: 2–13: p <.001).
Conclusions. Our findings suggest that the Breakthrough Collaborative led to an increase in donation rates at participating hospitals.     

选择性冠状动脉造影评价常规心电图ST-T改变在冠心病中的诊断价值

目的:评价常规心电图检查中ST-T改变在冠心病诊断中的价值。方法:以选择性冠状动脉造影为对照,研究连续194例病人临床症状及心电图ST-T改变与造影结果的关系。结果:造影发现136例病人有明显的冠状动脉狭窄性病变,58例未发现明显病变。非典型心脏症状的病人无论是否有ST-T的异常,冠状动脉造影的阳性率仅4%～14％,而典型症状伴有ST-T异常的病人阳性率较高(89.4％)。结论:ST-T异常伴有典型心脏症状的诊断冠状动脉病变的可靠指标。