早期动脉硬化斑块的MSCT动物实验研究及病理学对照

目的 探讨CTA对早期动脉硬化斑块的诊断价值.方法 通过高脂饮食建立15只新西兰大耳白兔的动脉粥样硬化动物模型,分别进行CT血管造影检查,并与病理结果进行对照,分析斑块的病理与影像表现.结果 动脉硬化模型成功建成.CTA检查发现25处斑块,其中2处为假阳性斑块,12处为脂纹斑块,11处为纤维斑块.约15%斑块具有一定易损性.结论 64排螺旋CT血管造影检查在发现早期动脉硬化方面中具有明显诊断价值.     

冠状动脉造影正常患者64排CT冠状动脉成像结果分析

目的 分析介入性冠状动脉造影正常患者64排CT冠状动脉成像的检查结果和影像特点.方法 对介入性冠状动脉造影结果为阴性的52例患者在1月内行64排CT冠状动脉成像检查,对阳性病例进行回顾性分析.结果 64排CT冠脉成像显示52例中,冠状动脉局限性管壁增厚29例(55.77%),管腔无狭窄23处,轻度狭窄6处,平均狭窄程度8%;弥漫性管壁增厚8例(15.38%),管腔无狭窄1例,轻度狭窄7例,平均狭窄程度为11%;单纯内膜钙化或管壁内钙化3例(5.77%),管腔未见明显狭窄.结论 64排CT冠状动脉成像更适宜作为冠心病诊断的首选影像检查方法.     

64层螺旋CT胸部低剂量扫描方案优选的多中心研究

目的 比较自动曝光控制技术(AEC)与管电流恒定技术(CCC)2种不同低剂量MSCT扫描方案对胸部CT图像质量的影响,探讨更加合理的肺低剂量扫描参数方案.方法 采用前瞻性多中心研究方法,研究对象为7所医院就诊的280例行胸部低剂量MSCT检查的受检者,设定管电流(mA)为研究变量,方法一为AEC技术,下设噪声标准差值(SD)为25(A1)及30(A2)各1组,并设定管电流上限为80 mA,下限为10 mA;方法二为CCC技术,下设40 mA(C1)及50 mA(C2)各1组;共4组,采用同一机型64层MSCT行胸部低剂量扪描.2名放射科医师应用双肓法阅片,比较2种不同扫描技术的曝光剂量、SD值,横断面、MPR的图像质量以及体质量指数(BMI)对图像质量的影响.曝光剂量及SD比较行方差分析及t检验;图像质量比较行Mann-Whitney检验;医师对图像诊断一致性检验行Kappa分析.结果 剂量长度乘积(DLP)AEC组较CCC组明显降低[(82.62±40.31)和(110.81±18.21)mGy·cm,F=56.88,P＜0.01].AEC技术中A2组DLP较A1组低[(72.77±36.68)和(92.46±41.61)mGy·cm],差异无统计学意义(t=0.82,P＞0.05).前者SD值在肺窗[(41.50±9.58)和(40.86±7.03)HU]及纵隔窗[(41.19±7.83)和(40.92±9.89)HU]均略高于后者,差异无统计学意义(F肺窗=0.835、1.910,P值均＞0.05).横断面图像质量AEC组肺窗得分除右下肺静脉水平[(4.92±0.25)和(4.93±0.17)分]、[左膈顶上缘水平(4.91±0.27)和(4.93±0.22)分]较CCC组略低外,AEC组得分均较CCC组略高[头臂静脉上缘(4.49±0.56)和(4.38±0.64)分;主动脉弓上缘(4.86±0.23)和(4.81±0.32)分;右肺上叶支气管开口(4.87±0.27)和(4.84±0.22)分;右肺中叶支气管开口(4.90±0.25)和(4.88±0.21)分],差异无统计学意义(F=0.076～1.748,P值均＞0.05);纵隔窗得分除头臂静脉上缘水平AEC组较CCC组高[(2.57±0.77)和(2.46±0.59)分],且差异有统计学意义(F=8.459,P=0.047)外,余各层面AEC组得分均较CCC组略低[(主动脉弓上缘(3.36±0.63)和(3.45±0.60)分;右肺上叶支气管开口(3.94±0.56)和(3.95±0.51)分;右肺中叶支气管开口(3.80±0.58)和(3.87±0.50)分;右下肺静脉(3.72±0.56)和(3.78±0.53)分;左膈顶上方(3.58±0.63)和(3.68 ±0.56)分],但差异均无统计学意义(F=0.083～3.380,P值均＞0.05).MPR图像质量肺窗及纵隔窗观察均略好于CCC组(Z肺窗=-2.358,Z纵隔窗=-1.330,P值均＞0.05).偏瘦、正常或偏重人群组,A1组肺窗及纵隔窗图像质量均优于A2组,差异无统计学意义(偏瘦:Z肺窗=0.000、Z纵隔窗=0.000;正常:Z肺窗=-0.062、Z纵隔窗=-0.746;偏重:Z肺窗=-1.177、Z纵隔窗=-1.715;P值均＞0.05),但在偏重人群纵隔窗图像质量A1组更好于A2组(Z=-1.715,P=0.144).结论 AEC组总曝光剂量明显低于CCC组,而AEC组的图像质量及SD值无论在肺窗或纵隔窗均与CCC组无明显差异,故建议在胸部低剂量筛查方案选择中应用AEC技术,对偏胖者宜采用SD=25方案,对正常及偏瘦者宜采用SD=30方案.

Abstract：

Objective To compare the image quality of chest low dose CT (LDCT) using automatic exposure control (AEC) and constant current control (CCC) and explore a more reasonable scanning protocol. Methods Two hundred and eighty participants were examined with 64 CT scanner at 7 centers in China. All were divided into 4 groups. Two groups underwent LDCT using AEC with standard deviation set at 25 (A1) and 30 (A2) respectively and the tube current ranged from 10 mA to 80 mA. The other two groups underwent LDCT using CCC with tube current set at 40 mA (C1) and 50 mA (C2) respectively. The axial and MPR images were evaluated by two radiologists who were blinded to the scanning protocols.The radiation dose, noise and the image quality of the 4 groups were compared and analyzed statistically.Differences of radiation dose and noise among groups were determined with variance analysis and t test,image quality with Mann-Whitney test and the consistency of diagnosis with Kappa test. Results There was a significant lower DLP in AEC group than in CCC group [(82.62±40.31)vs ( 110.81±18.21) mGy·cm (F =56. 88 ,P ＜ 0. 01 )], whereas no significant difference was observed between group A2 and group A1 0. 05]. The noisy of AEC group was higher than that of CCC group both on lung window(41.50±9.58 vs 40.86±7.03) and mediastinum window (41.19±7.83 vs 40.92±9.89), but there was no significant difference( Flung =0.835, P=0.476, Fmediastinum =1.910, P=0.128).The quality score of axial image in AEC group was higher than that in CCC group (superior margin of the brachiocephalic vein level: 4.49±0.56 vs4.38±0.64,superior margin of the aortic arch: 4.86±0.23 vs 4.81±0.32,the right superior lobar bronchus Level:4.87±0.27 vs 4. 84 ± 0. 22, the right middle lobar bronchus Level: 4.90±0.25 vs 4.88±0.21) except on the right inferior pulmonary vein level(4. 92 ±0. 25 vs 4. 93 ±0. 17) and superior margin of the left diaphragmatic dome level (4. 91±0.27 vs 4.93±0.22) on lung window, but no significant differences (F=0.076-1.748, P＞0.05) were observed. A significant higher score in AEC group was observed on mediastinum window compared with CCC group on superior margin of brachiocephalic vein level (2.57±0.77 vs 2. 46 ± 0. 59, F = 8. 459, P ＜ 0. 05 ), however, the score of AEC group was lower than that of CCC group on other levels without significant differences (superior margin of the aortic arch:3.36 ±0. 63 vs 3.45 ±0. 60,the right superior lobar bronchus level: 3.94 ±0. 56 vs 3. 95 ±0. 51 ,the right middle lobar bronchus Level: 3.80 ±0. 58 vs 3. 87 ±0. 50,the right inferior pulmonary vein level: 3.72 ±0. 56 vs 3.78 ±0. 53, superior margin of the left diaphragmatic dome level: 3.58 ± 0.63 vs 3.68±0.56,F=0.083-3.380,P ＞ 0.05 ). The MPR image quality of AEC group was better than that of CCC group both on lung window and mediastinum window (Zlung =-2.258, Zmedlastinum=-1.330, P＞0.05). For all participants including the underweighted group, the normal group and the overweighted group, the image quality of A1 group was better than that of A2 group without significant differences (the underweighted group: Zlung=0.000, P=1.000, Zmedastinum= 0.000, P=1.000;the normal group: Zlung =-0.062, P=0.950, Zmediastinum =-0.746, P = 0.456; the overweighted group: Zlung = - 1.177, P = 0.239,Zmediastinum =-1.715, P=0.144) both on lung and mediastinum windows, and for the higher BMI participants, a better image quality was obtained in A1 group than in A2 group on the mediastinum window (Z = -1. 715, P = 0. 144). Conclusions The total radiation exposure dose of AEC group is significantly lower than that of CCC group, but no statistical significant differences are observed between both groups in image quality and noise level. The AEC technique is highly recommended in thoracic LDCT scan for screening program, and the SD25 ( SD value = 25) scan protocol is suggested for higher BMI population while the SD30 (SD value = 30) scan protocol for lower BMI population.     

64排螺旋CT对急性肠梗阻定位与定性诊断的准确性

目的分析64排螺旋CT对急性肠梗阻的诊断价值。方法 42例手术病理证实的急性肠梗阻患者均行腹部CT扫描,分析其影像表现并与手术结果对照。结果梗阻部位包括:小肠26例,回盲部4例,结肠10例,直肠4例。与手术结果对照,CT对梗阻的定位诊断准确率为95.2%(40/42),定性诊断正确率为81%(34/42)。结论 CT可以清晰显示梗阻部位,对肠梗阻的定性诊断也有一定价值。     

2008-2018年中国5岁及以下儿童手足口病死亡病例流行病学特征

目的 分析2008-2018年我国≤5岁儿童手足口病死亡病例的特征,为制定针对性措施,减少死亡病例发生提供依据。方法 从全国疾病监测信息报告管理系统中收集2008-2018年手足口病监测数据,采用描述性分析方法分析手足口病死亡病例的人群特征、空间分布、诊断和报告情况及病原构成变化,采用logistic回归模型分析导致死亡的危险因素。结果 2008-2018年全国共报告手足口病≤5岁儿童死亡病例3 646例,男性多于女性（1.82：1）,以≤2岁儿童为主（87.71%）。2010年之后全国≤5岁儿童报告手足口病调整后的死亡率由0.87/10万下降至2018年的0.11/10万（APC=-23.20%）。2 523例实验室确诊的死亡病例中,2 323例（92.07%）为肠道病毒71型（EV-A71）感染,但柯萨奇病毒A组16型（CV-A16）和其他肠道病毒构成呈现增加趋势。死亡病例发病至诊断时间间隔M=2（P₂₅～P₇₅：2～4）d,发病至死亡时间间隔M=3（P₂₅～P₇₅：2～4）d。0～1岁、EV-A71感染、发病诊断时间间隔较长和居住地为农村是手足口病死亡的危险因素。结论 2010年后,我国手足口病死亡水平呈下降趋势;死亡病例中优势病原仍为EV-A71,应加强死亡病例中非EV-A71和非CV-A16肠道病毒基因分型;西部省份、农村地区和小年龄组病例应当加强EV 71灭活疫苗接种宣传,提高诊断、救治及时性,降低死亡风险。     

多自由度载人离心机分布式安全防护系统设计

目的：针对多自由度载人离心机系统庞大、监控信号多且类型复杂、载荷高等问题,研发一种保护离心机设备和受试者的安全防护系统。方法：该系统采用分布式主从结构设计,硬件由座舱从站、主臂从站、地下室从站和安全主站等组成,其中主站采用西门子S7-400 PLC实现,从站采用西门子ET200M远程输入/输出（input/output,I/O）模块进行配置。从站采集离心机分部件状态参数并进行整合,主站获取从站数据,经分析后采取警告、报警和急停等措施保护系统安全。上位机软件平台基于LabVIEW 2018开发。结果：该系统能够实现对多自由度载人离心机状态参数的实时监控、报警推送和应急处理等功能,保护离心机设备和受试者安全。结论：该系统具有监控颗粒度高、保护全面等优点,能够满足载人离心机运行和维护的多级安全监控需求。     

异搏定抢救电复律无效持续性室速一例

(一)临床资料患者男性,34岁,因突感心悸、胸闷伴头昏一小时,于1994年4月7日入院。1993年6月患频发室早、短阵室速(NSVT),诊断病毒性心肌炎住院,口服慢心律、心律平、乙胺碘呋酮无效、改服异搏定40mg每天三次,康复出院,继服此药,未再复发,近二日来自行停药。入院查体:     

人体抗荷正压呼吸时抗荷耐力及T淋巴细胞亚群变化

抗荷正压呼吸(PBC)是现代战斗机抗高过载的主要抗荷措施之一。本研究观察了采用PBC进行 Gz暴露时T淋巴细胞亚群的变化,探讨 Gz暴露对机体免疫功能的影响。     

辛伐他汀对马兜铃酸大鼠肾间质纤维化防治的作用

马兜铃酸（AA）肾病可引起肾衰竭,与其它慢性肾病一样有着共同的通路均表现为肾间质纤维化,这一改变是不可逆转的进行性发展,而且预后不良。在临床上早期发现其肾脏纤维化,并进行早期防治是预防慢性肾衰竭的最重要的方法之一。为此,我科应用辛伐他汀对AA所致的慢性肾脏纤维化进行防治性分析。