超声定量检查技术新进展

近年来，超声定量检查技术在临床的应用为心血管疾病患者的心功能评估提供了量化的依据，本文介绍了超声诊断仪的使用部分最新定量检查技术。     

骨盆骨折槽型固定器的研制及临床应用——附62例临床分析

为解决骨盆不稳定性骨折固定难，易产生并发症的难题，结合骨盆的特征进行研究，设计出一种新型骨盆骨折固定器，经62例骨盆不稳定性骨折的治疗观察，随访6个月～2年零6个月，治疗前后X线检查及临床疗效评定：治愈50例，好转12例，认为该固定器设计合理，操作简便，固定牢靠，有加压、撑开、纠正旋转等多项功能结合干一体，仅通过四枚4mm螺纹针，穿入髂骨的髂前上棘处，是一种治疗骨盆不稳定性骨折比较新颖和理想的外固定器。     

Reproducibility of lateral spine scans using dual energy X-ray absorptiometry

Summary Reproducibility of lateral spine dual energy X-ray absorptiometry (LAT DEXA) scans using a Lunar DPX-L scanner was assessed in a cadaveric phantom and in patients. One hundred phantom measurements over 7 months demonstrated a longitudinal stability of 1.7% (coefficient of variation, CV). Additional scans were performed with the phantom rotated by up to 20° in each of the three orthogonal planes to assess the effects of variable patient positioning. Horizontal and vertical rotation of the spine had little effect on the estimated bone mineral density (BMD), however, axial rotation of greater than 8° led to errors in the BMD measurement. One hundred consecutive patients had two lateral scans performed within 1 month. BMD (range 0.10–1.6 g/cm²) was determined for each scan by one operator. Significant overlap from ribs and pelvis was often seen with L2 and L4 vertebrae but one vertebra (L3) could be measured in every case. Intraoperator and interoperator variability was assessed by three experienced operators, each analyzing 10 patients' scans on five separate occasions, and was found to be less than 1.1% for a single vertebra. BMD estimation of vertebral bodies and midslices by lateral DEXA scans (CV% of 3.8% and 4.6%) have a 95% confidence interval of 0.074 g/cm² and 0.096 g/cm², respectively for two vertebrae. This variability is due mainly to axial rotation, with operator variability, horizontal rotation, and vertical rotation having little effect on BMD estimation.     

H—TdR前体掺入技术在复方中药抗癌制剂研究中的应用

将一种快速、灵敏、可靠、简便的抗癌活性微量测定技术——~3H—TdR前体掺入技术用于复方中药抗癌制剂制备工艺筛选,短期内即拟定出较合理的工艺,经临床及14项生物学指标综合评定,该制剂疗效好,无明显的毒副作用。表明把一些快速、灵敏的医学检测技术引入药物制备工艺、质量标准及稳定性研究,可克服由于活性成分不清楚带来的一些困难,拓宽了研究途径,提高了研究水平。     

双向线性能量和负压控制及不旋转核技术在晶状体悬韧带脆弱的白内障超声乳化手术中的应用

目的探讨双向线性能量和负压控制及不旋转核技术在晶状体悬韧带脆弱的白内障超声乳化手术中应用的临床效果。方法对220例(233只眼)悬韧带脆弱的白内障患者,应用双向线性能量和负压控制系统的高负压低能量技术结合不旋转核超声乳化法行白内障超声乳化联合人工晶体植入术。记录术中能量和相对能量复合参数以及并发症发生的情况,同时观察术后早期(1周内)和晚期(9～26个月)的矫正视力以及并发症发生情况。结果术后视力有明显提高。术前即存在轻度晶状体脱位(悬韧带断离范围小于1/4圆周)的15只眼中3只眼术中发生悬韧带断离范围轻度扩大(扩大范围小于1/8圆周);其它手术前未发现晶状体脱位的218只眼中2只眼术中发生局限性(小于1/8圆周)悬韧带断离。术后早期角膜一过性轻度水肿35只眼,15.2%;前房少量出血5只眼,2.1%;轻微虹膜炎45只眼,19.3%;瞳孔欠圆16只眼,6.9%。术后晚期前囊膜混浊122只眼,52.4%;前囊口收缩综合症5只眼,2.1%;后囊膜混浊76只眼,32.6%;人工晶体移位13只眼,5.6%;视网膜脱离3只眼,1.3%。结论利用双向线性能量和负压控制系统的高负压低能量技术结合不旋转核超声乳化法能最大程度地减少对晶状体悬韧带的旋转力和牵拉力,同时还降低了超声能量对悬韧带的冲击力,可最大限度地避免悬韧带的离断。     

Temperature-controlled radiofrequency catheter ablation of AV conduction: first clinical experience

A new technique for catheter ablation of atrioventricular (AV)conduction, using temperature-controlled radiofrequency energyand a bipolar asymmetrical electrode configuration, was appliedto 12 patients (mean age, 48 ± 15 years; range, 18–69years) with medically refractory atrioventricular nodal reentranttachycardia (AVNRT) or rapid atrial rhythms. The energy sourcewas a 500 kHz generator with automatic power regulation to apreselected temperature of 80 °C. A specially designed 7F bipolar asymmetric thermo-catheter was used for ablation inall cases. The endpoints of the procedure were: first-degreeAV block in patients with AVN R T and third-degree block inpatients with atrial fibrillation or flutter. Energy was appliedover a range of 1–14 times per patient. After a mean follow-upof 8±4 months, third- or first degree AV block persistedin eight patients. In comparison to constant-power radiofrequencyablation, where impedance rises are commonly observed, no impedancerise or coating of the electrode occurred during any of the97 energy applications in this study. Variable wall contactof the electrode was identified in 20 of 97 applications bya slow temperature rise or a drop in temperature and frequentpower adjustments. Thus, monitoring temperature and automaticpower regulation may help to reduce the total delivered energy.Temperature control during radiofrequency energy avoids coagulumformation and consequently the associated potential hazardsof constant-power application.     

The ‘limits’ of medicalization?: Modern medicine and the lay populace in ‘late’ modernity

Taking as its point of departure the medicalization thesis and its limitations, this paper provides a critical discussion of certain more recent theoretical perspectives on life in contemporary society, and their relevance for understanding the relationship between modern medicine and the lay populace. In particular, attention is paid to the contours and existential parameters of life in ‘late’ modernity in terms of the following four key themes: (i) modernity as a ‘reflexive’ social order; (ii) ‘risk’ and the dialectic of scientific and social rationality; (iii) the ‘mediation’ of contemporary experience; and (iv) lay ‘re-skilling’ and the ‘life political’ agenda. On the basis of this, it is argued that far from being simply passive and dependent, a ‘critical distance’ is beginning to emerge between modern medicine and the lay populace; a situation which resonates with broader social trends and currents within society at large.     

Crossed inhibition of the soleus H reflex during passive pedalling movement

We hypothesized that sensory input from the moving leg induces presynaptic inhibition of the soleus H reflex pathway in the contralateral stationary leg. The results showed a crossed inhibition during passive pedalling movement of the leg, which was not removed by low levels of tonic contraction of soleus in the stationary leg. The inhibition was correlated exponentially to the rate of the movement (R²=0.934, P<0.05) and was not dependent on the quadrants through which the moving leg was passing. Static flexion of the stationary leg caused ipsilateral inhibition of the reflexes (t=5.590, P<0.05), independent of the orientations of the other leg. We concluded that sensory inflow from the moving leg induces presynaptic inhibition in the stationary leg, that a complex transformation of the sensory input in the spinal cord or brain underlies the tonic crossed inhibition and phasic ipsilateral inhibition, and that descending motor commands exert a powerful control over these sensorimotor modulatory mechanisms.