1.5T超导磁共振制冷系统的工作原理及日常维护

介绍GE 1.5T超导磁共振制冷系统的组成和工作原理,讨论日常维护的要点及其必要性。     

动态监测胃黏膜内pH值对胆源性胰腺炎外科治疗的价值

目的探讨胃黏膜内pH值对胆源性胰腺炎病情预后评估及在决定手术冶疗中应用的价值。方法对确诊的146例胆源性胰腺炎患者经鼻插入胃黏膜二氧化碳张力计（TRIP-NGS导管）测定胃黏膜内pH值，每隔12小时测定一次，并进行APACHEⅡ评分，将2组数据与外科治疗进行相关分析。结果①pH值变化反映胆源性胰腺炎病情发展变化，与器官衰竭数呈负相关；②外科干预治疗与内科治疗比较差异有统计学意义（P〈0．05）；③pHI〉7．25与pH〈7．25患者开腹手术病死率和细菌培养阳性率比较差异有统计学意义（P〈0．05）。结论pH值对胆源性胰腺炎外科治疗有指导意义。外科处理原则是：①胆道无梗阻，以内科保守治疗为主；②伴胆道梗阻，先行经内镜十二指肠乳头括约肌切开术、经内镜鼻胆管引流术、B超导引引流、腹腔灌洗等，如胆道引流不畅或pH值持续下降，则开腹手术。     

乳母血清泌乳素水平与泌乳量关系的观察

用放射免疫法测定产后40天和60天乳母血清泌乳素基础水平和吸吮后泌乳素最大反应性增值,发现其与乳母泌乳量、婴儿吸吮频率、吸吮时间之间均不存在正相关关系,推测引起泌乳素分泌除吸吮外,还存在其他机理。     

1000例白鼻毛调查

在1000人中统计白鼻毛发生率为36.4%,白发为26.1%,白须为7.5%,白眉为3.3%,白睫为1.6%。我们认为白鼻毛比白发等作为衰老的一项指标更有其代表性。白鼻毛发生率:男性(53.4%)高于女性(13.4%),知识分子(60.8%)高于工人(26.3%)及农民(26.4%),日本人高于中国人,差异显著。     

持续压力超负荷对兔左心室细胞凋亡的影响

OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious.     

Biomechanical evaluation of spinal stability after disc injury in a porcine model

The biomechanical effects of disc injury on flexion-extension were investigated in nine fresh porcine functional spinal units. Under 12 N-m in extension and 6 N-m in flexion, the range of motion among intact specimens were 23.11 degrees -33.29 degrees (mean = 26.07 degrees , SD = 3.25 degrees ), which shifted to 28.04 degrees -38.46 degrees (mean = 31.69 degrees , SD = 3.50 degrees ) when discs were injured. Similarly, the neutral zones among intact and disc injured specimens were 4.88 degrees -12.75 degrees (mean = 9.32 degrees , SD = 2.60 degrees ) and 9.50 degrees -24.43 degrees (mean = 16.80 degrees , SD = 4.69 degrees ) respectively. To obviate the differences between tested specimens, the changes of neutral zone and the range of motion after disc injury were normalized and expressed as ratios as compared to the same items before disc injury. The neutral zone ratio ranged from 1.29 to 3.18 (mean = 1.87, SD = 0.55, p < 0.01). For range of motion, it ranged from 1.13 to 1.42 (mean = 1.22, SD = 0.09, p < 0.01). The change of flexibility coefficient, however, was statistically insignificant in either flexion or extension. The model presented defines the range of motion, the neutral zone as well as the flexibility coefficient under a specific load. It suggests that major spinal instability can be elicited by a minimum flexion-extension moment, as reflected by a profound change of the neutral zone, after disc injury.     

Passive exercise system: effect on muscle activity, strength, and lean body mass.

There is little information concerning the effects of passive exercise training in healthy humans. This prompted an investigation to evaluate muscle activity and the associated changes in strength and lean body mass resulting from a passive exercise program. Twenty-eight healthy volunteers, aged 26 to 44 years, participated in this six-week study. Lean body mass changes were evaluated by tetrapolar bioelectric impedance measurements, strength changes by isokinetic strength evaluation, and muscle activity by surface EMG techniques. Reproducible muscle activity was recorded in all three muscles studied during two of three preselected exercises. This involuntary muscle activity was attributed to fusimotor and postural reflexes. No significant change (p greater than .05), however, occurred in muscle strength or lean body mass at the end of the six weeks. Lack of these physiologic changes in light of the documented muscle activity is attributed to insufficient training effect.     

Patient attitude towards waiting in an outpatient clinic and its applications.

Patient waiting time in outpatient clinics is often the major reason for patients' complaints about their experiences of visiting outpatient clinics. Therefore, patient satisfaction with waiting time plays a crucial role in the process of health quality assurance or quality management. This paper reports the results of a survey on patient attitude towards waiting in an outpatient surgery clinic. Generally patients appear reasonably satisfied if they wait no more than 37 minutes when arriving on time, and no more than 63 minutes when late for appointments. Patients coming up to 15 minutes early are prepared to take full responsibility for the extra waiting caused, but the patients coming even earlier intend to be seen earlier and are only prepared to wait 15 minutes longer than otherwise. The potential applications of patient attitude towards waiting in the quality assurance process, ie setting up waiting time limits and designing patient dispatching rules, are also discussed.