PET/CT图像采集时间对图像质量和病灶检出率的影响

目的探讨在不影响图像质量和病灶检出率前提下缩短PET／CT图像采集时间的可行性。方法18例接受PET／CT检查的患者，在CT扫描后按1、2、3min／床位依次进行3次PET扫描，共得到54帧图像。患者按体重分为以下3组：（1）45～60kg（7例），（2）61～75kg（7例），（3）76～90k（4例）。由2位有经验的医师共同阅片确定每例患者病变的位置和数目，图像质量由2位医师独立判断。结果3min／床位PET／CT图像上共检出127个病灶，其中最小的病灶直径约为3mm，除1min／床位图像漏检3个病灶外，其他所有病灶均能被1min／床位、2min／床位的图像识别。（1）～（3）组患者在3min／床位采集图像上识别的病灶数分别为71、41、15个，第1组患者的所有病灶在3种不同采集时间图像上均能被识别，第2组患者1min／床位采集图像遗漏了3个病灶，而2min／床位图像识别出的病灶数与3min／床位图像相同。第3组患者的所有病灶在3种采集图像上也均能被识别。1、2min／床位的PET图像质量均较3min／床位图像差，1min／床位图像质量最差，主要表现为图像本底噪声高、对比度差。3组患者中，第3组患者图像质量最差。结论对体重低于60瞻患者，1～3min的采集时间，病变的检出率无明显差异；而对体重60k以上患者，建议选择2～3min／床位的采集时间，对病情较重或不合作患者，根据需要可考虑选择1min／床位的采集时间。     

Effects of self-management training in Type 2 diabetes: a randomized, prospective trial.

AIMS: The efficacy of three education programmes for Type 2 diabetic patients was tested in a randomized trial. A didactic-oriented training programme (treatment A) was compared with a self-management-oriented programme delivered in group sessions (treatment B). The latter programme was compared with a more individualized approach (treatment C). METHODS: One hundred and eighty-one Type 2 diabetic patients (age 55.6 +/- 6.3 years, diabetes duration 6.6 +/- 6.2 years, HbA(1c) 7.8 +/- 1.6%, female 49.7%) took part. Efficacy was assessed 3 months (t1) after baseline (t0) and at a follow-up 15 months (t2) after baseline. RESULTS: The fall in HbA(1c) in treatment B at t1 was sustained at t2 (t0 8.1 +/- 1.8%, t1 7.3 +/- 1.7%, t2 7.4 +/- 1.9%). In treatment A, HbA(1c) was unchanged throughout (t0 7.6 +/- 1.5%, t1 7.5 +/- 1.3%, t2 7.7 +/- 1.7%; treatment A vs. treatment B; P < 0.05). With the more individualized approach of treatment C, there was a fall in HbA(1c) at t1, but this was not sustained at t2 (t0 7.8 +/- 1.6%, t1 7.1 +/- 1.3%, t2 7.6 +/- 1.6%; treatment B vs. treatment C; P = 0.73). There were also significant benefits in treatment B subjects compared with treatment A in further medical (body mass index and fasting blood glucose), psychological (control, irritability and hunger dependency of eating behaviour, and trait anxiety) and behavioural (exercise) variables. There were no significant benefits of the more individualized treatment C compared with group treatment B. No significant differences were found regarding triglyceride levels, high-density lipoprotein, diabetes-related knowledge, negative well-being, urine or blood glucose levels or foot care. CONCLUSION: Self-management training had a significantly higher medium-term efficacy than didactic diabetes education. The group sessions were more effective than a more individualized approach.     

The effects of altering time delays of coupled pacing during acute atrial fibrillation

BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied.     

1992～2001年海南省结核病防治工作情况分析

目的　分析海南省结核病防治工作现状和经验。方法 根据全省各市(县)上报的结核病报表和有关总结材料,分析结核病现状、防治对策及效果。结果 海南省应用现代结核病控制策略以来,1992～2000年共检查可疑肺结核病患者192077例,查痰48670例,查痰率25.3%。发现并登记活动性肺结核病人31822例,其中涂阳病人22946例,涂阳新登记率从1992年12.8/10万上升到2000年48.4/10万。至2001年12月止,共治愈了21625例涂阳病人,总治愈率达94.2%。结论 海南省结核病疫情严重,近10年来经过应用现代结核病控制策略,取得显著成效,证明该策略是控制结核病流行最有效的技术措施。     

开放性骨质疏松性股骨远端骨折的治疗和伤害控制论的应用

目的 总结治疗开放性骨质疏松性股骨远端骨折的治疗和应用伤害控制观念的体会。方法 回顾性分析2002年1月～2003年12月60岁以上股骨远端开放性骨折住院治疗的病例21例。应用伤害控制学的原则：全面评价其外伤程度，条件允许则急诊手术，危重患者就临时固定，监护患者的生理指标，限期施行骨折固定手术。结果 17例患者获得超过4个月以上的随访，平均随访7．3个月。17例患者在术后平均15周内(79～168d)达到临床愈合。参照Shelbourne疗效评定标准，膝关节功能优良率达到78％。结论 治疗开放性股骨远端骨质疏松性骨折需要应用伤害控制的观念，兼顾患者全面情况，同时治疗骨质疏松和其它并存疾病。手术固定以股骨髁上逆行交锁髓内钉为主，早期功能锻炼。     

失血性休克大鼠肠上皮细胞线粒体DNA腺苷三磷酸酶6,8基因表达及线粒体功能的改变

目的　探讨失血性休克大鼠肠上皮细胞线粒体DNAATPase 6 ,8基因表达及线粒体功能的改变 ,为阐述休克肠道靶学说和线粒体能量代谢提供分子生物学基础。　方法　 2 4只Wistar大鼠随机分为休克前组和休克 1,2 ,3,4 ,5h组。采用RT -PCR方法观察线粒体ATPase 6 ,8mRNA量的改变。用透射电镜观察、生物体视学测量线粒体形态 ,用Clark氧电极测线粒体呼吸功能。　结果　失血性休克 1,2h ,ATPase 6 ,8基因表达增强 ,以后渐减弱 ,至休克 5h表达最低 ,ATPase 6 ,8基因表达分别降为正常的 6 9.3%和 78.4 % (P <0 .0 1和P <0 .0 5 )。失血性休克 2h和5h ,线粒体平均截面积、长径、面密度、体密度均显著增加 (P <0 .0 1) ,休克 5h时分别为休克前的2 .0 ,1.4 5 ,1.4 7,2 .2 2倍。休克 5h ,线粒体比表面和数密度分别下降 32 %和 2 4 % (P <0 .0 1和P <0 .0 5 ) ,嵴和基质破坏明显。失血性休克后肠上皮细胞线粒体呼吸控制率和氧化磷酸化效率比休克前显著降低 (P <0 .0 1)。　结论　失血性休克时大鼠肠上皮细胞线粒体DNAATPase 6 ,8基因表达下调 ,线粒体呼吸功能出现障碍 ,线粒体超微结构发生了改变     

Family Stress and Functioning in Children: the Moderating Effects of Children''s Beliefs About Their Control Over Parental Conflict

While factors such as gender and SES have been studied as moderators of stress for children, their perceptions of control have received little attention. In the current study, children's domain-specific perceptions of their control during marital conflict were investigated as potential moderators of the impact of family stress on children's behavior problems, and perceptions of competence. Ninety-four children aged 6-12 years and mothers from families ranging in level of parental conflict from nondiscordant to discordant to physically violent were interviewed. Multiple regression analyses revealed that higher levels of conflict control beliefs acted as compensatory moderators of stress, being associated with lower levels of problem behaviors across stress levels. However, higher conflict control beliefs acted as vulnerability moderators with regard to children's perceptions of competence.     

躯干运动和负重时对足底支撑面侧向横移的姿势控制

目的:本研究假设自主运动命令和姿势控制信号间有冲突,因此设计在附加重物和不同自主任务的同时给予足底一个模拟受滑的干扰(横移)来观察姿势变化并分析其是否受冲突命令或者力学参数的影响.方法:受试者在执行各种不同的自主任务时,随机给予足底支撑面一个左侧或右侧的横移干扰.这些不同的自主任务包括不负重静止站立、静止站立单手负重5kg、负重5kg站立并躯干静止侧屈15°、负重5kg动态地提重物和放重物5项任务.测量和分析下列参数:中心压力的侧位移(COP)、躯干和股部在冠状面上的角位移和腹内压(IAP).结果:干扰离开质量(向右)、始反应超射的幅度、达到终平衡的时间和达到平衡前COP位移的次数都增加,这种情况可以看作是为了再获得平衡的姿势反应效率降低,因此,如果质量的重力效果能对抗干扰,则再获得平衡的反应效率甚至可以被增进.结论:提重和负重是危害姿势反应效率的因素,因为提重和负重改变了重力效果,加大了对躯干的干扰.在动态条件下躯干的运动不是被横移干扰增强就是被横移干扰抵消,并没有显著地影响改变最终平衡位置姿势校正的效应.因此附加任务的同时给一个支持面上的横移干扰,姿势控制的效应可以被抵消.这个减低的效应可以引起脊柱周围结构的负荷增加和增加受伤的危险性.但是,在恰当地放置负重的位置时,反而可以增进躯干控制和协助恢复姿势平衡.     

带随机输出噪声的参考模型自适应系统

讨论了带随机输出噪声的线性时不变对象的参考模型自适应系统。提出一种适用于这种系统的混合自适应控制律,证明该系统所有信号的有界性,计算机仿真验证这种新的混合自适应控制律在存在随机输出噪声的系统中的性能。