Continuously moving table 3D MRI with lateral frequency-encoding direction.

A method is presented for 3D MRI in an extended field of view (FOV) based on continuous motion of the patient table and an efficient acquisition scheme. A gradient-echo MR pulse sequence is applied with lateral (left-right (L/R)) frequency-encoding direction and slab selection along the direction of motion. Compensation for the table motion is achieved by a combination of slab tracking and data alignment in hybrid space. The method allows fast k-space coverage to be achieved, especially when a short sampling FOV is chosen along the direction of table motion, as is desirable for good image quality. The method can be incorporated into different acquisitions schemes, including segmented k-space scanning, which allows for contrast variation with the use of magnetization preparation. Head-to-toe images of volunteers were obtained with good quality using 3D spoiled gradient-echo sequences. As an example of magnetization-prepared imaging, fat/water separated images were acquired using chemical shift selective (CHESS) presaturation pulses.     

电子直线加速器照射对NIH 3T3细胞的细胞周期及凋亡的影响

目的 探讨电子直线加速器照射对细胞周期及细胞凋亡的影响。方法 采用直线加速器对NIH 3T3细胞进行照射，观察细胞周期及细胞凋亡的改变情况；同时测定损伤前后p53蛋白的表达情况。结果 照射后细胞凋亡数增加，p53蛋白表达量上升。结论 电子直线加速器照射损伤可诱导细胞凋亡。     

Image processing in digital radiography

Image processing is a critical part of obtaining high-quality digital radiographs. Fortunately, the user of these systems does not need to understand image processing in detail, because the manufacturers provide good starting values. Because radiologists may have different preferences in image appearance, it is helpful to know that many aspects of image appearance can be changed by image processing, and a new preferred setting can be loaded into the computer and saved so that it can become the new standard processing method.Image processing allows one to change the overall optical density of an image and to change its contrast. Spatial frequency processing allows an image to be sharpened, improving its appearance. It also allows noise to be blurred so that it is less visible. Care is necessary to avoid the introduction of artifacts or the hiding of mediastinal tubes.     

X-刀治疗靶点定位精确度分析

目的 :研究SRS2 0 0X 刀治疗系统治疗靶点定位的精确度。方法 :应用人体头颅模型内特定标记物测定CT定位的精度 ,用胶片法测定二次等中心系统精度和总的治疗精度。结果 :BRW头环CT定位精度为 0 .65mm ,最大误差为 1 .0 9mm ;SRS2 0 0二次等中心系统误差为 0 .1 9mm ;总治疗误差理论计算值为0 .68mm ,胶片法检测值为 1 .43mm。结论 :X 刀治疗系统精确度已达到放射外科质量控制要求。     

瓦里安2300C/D直线加速器COLL联锁故障检修

介绍和讨论瓦里安 2300C/D直线加速器 COLL联锁故障的发生原因和检修.     

直线加速器十年故障分析总结

目的分析和总直线加速器十多年来的故障。方法根据十多年来的故障维修记录，统计和分析直线加速器各阶故障率及故障特点。结果直线加速器使用早期由于机器不稳定故障率比较高，使用中期及其比较稳定，故障率比较低，使用后期由于零部件老化，故障率比较高。     

与时俱进 全面开展生活方式教育

该文从疾病谱和死因谱的改变、医学模式的转变、卫生经费的降低、自我保健意识的改变四个角度,论述了全面开展 生活方式教育的必要性和重要性;从以社区为依托、以医院为基础、以生活方式为指导三个方面,探讨了生活方式教 育的工作模式.     

X刀治疗脑内病变283例长期随访研究

目的:总结X刀治疗脑内病变的长期随访结果.方法:对283例X刀治疗的脑瘤和脑血管畸形患者进行临床和影像学随访,随访时间为1～8年,平均(2.05±4.66)年.结果:82例转移瘤消失35例(42.7％),缩小28例(34.1％),无变化11例(13.4％),增大8例(9.8％);61例胶质瘤消失10例(16.4％),缩小19例(31.1％),无变化16例(26.2％),增大16例(26.2％);55例动静脉畸形消失29例(52.7％),缩小20例(36.4％),无变化6例(10.9％);17例海绵状血管瘤缩小4例(23.5％),无变化13例(76.5％);35例脑膜瘤消失5例(14.3％),缩小15例(42.9％),无变化13例(37.1％),增大2例(5.7％);12例神经鞘瘤消失3例(25.0％),缩小6例(50.0％),无变化2例(16.7％),增大1例(8.3％);10例生殖细胞瘤消失8例(80.0％),缩小2例(20.0％);11例其他肿瘤消失2例(18.2％),缩小4例(36.4％),无变化4例(36.4％),增大1例(9.0％).影像检查还发现病灶有坏死表现99例,囊性变19例,周边环状强化73例,胶质细胞增生20例,暂时性反应性肿大23例,放射性脑水肿28例.结论:X刀对小型脑肿瘤和血管畸形是一种安全有效的治疗方法,X刀治疗的主要并发症是放射性脑水肿.     

三种淫羊藿的总黄酮分极提取物对小鼠免疫功能的影响

观察了巫山淫羊藿、柔毛淫羊藿和粗毛淫羊获的总黄酮正丁醇提取物（代号Ａ１、Ａ２、Ａ３）和巫山淫羊藿总黄酮乙酸乙酯提取物（Ｂ１）对正常小鼠免疫功能的影响。结果；Ａ１可以明显促进脾脏抗体形成细胞的功能（Ｐ＜０．０５），Ａ２、Ａ３虽也有一定的促进作用，但无统计学意义；４种提取物在体外实验中均没有协同ＣｏｎＡ诱导牌细胞增殖作用，只有提取物浓度在１００μｇ／ｍｌ时，有一定抑制作用。４种提取物对２４小时培养脾细胞存活率无明显影响。     

支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌

目的　研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法　 76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1～ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果　临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论　支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高