超声波在医疗领域中的应用及分析例举

本文简要介绍了超声波的三个特点，并从诊断、治疗、辅助用途三方面论述了超声波在临床的普遍应用，其中重点介绍了三维超声成像技术。     

胫骨前肌疲劳时比目鱼肌诱发肌电图H波的变化及其机制探讨

为了解主动肌疲劳时拮抗肌脊髓运动神经元兴奋性变化的规律 ,本研究采用踝关节背屈运动形式 ,对胫骨前肌 (主动肌 )疲劳状态下的比目鱼肌 (拮抗肌 )诱发肌电图H波成分进行了观察。并以压迫阻断胫骨前肌Ⅰa类神经纤维传导的方法 ,对比目鱼肌H波变化机制进行了分析探讨。结果发现 :(1)胫骨前肌疲劳后 ,比目鱼肌H波明显受到抑制 ,与安静时比较呈非常显著性差异 ;(2 )胫骨前肌Ⅰa类神经纤维传导被阻断后 ,比目鱼肌H波的抑制现象没有解除。表明 ,胫骨前肌疲劳时比目鱼肌H波被抑制的原因 ,可能是由于主动肌内的代谢产物激活了Ⅲ·Ⅳ类神经纤维的感受器 ,Ⅲ·Ⅳ类神经纤维的传入冲动增加 ,使Ⅰa抑制性中间神经元被激活 ,导致拮抗肌脊髓运动神经元的兴奋性受到了抑制     

Q开关Nd:YAG激光不同波长治疗面部毛细血管扩张疗效比较

目的：观察Q开关Nd：YAG激光不同波长治疗面部毛细血管扩张的疗效及副反应。方法：128例病人按治疗波长随机分为532nm组75例，585nm组53例，治疗光斑2．0mm，能量密度2．2-6．8J／cm。，脉宽10ns；术后3个月根据术前照片判定疗效，标准分为Ⅳ级。结果：治疗次数1-4次，间隔时间3-5个月，两组共治愈71例(55，47％)，疗效与治疗次数成正相关。其中532nm组治愈36例(48．00％)，平均治愈次数2．64次；585nm组治愈35例(66．04％，)，平均治愈次数2．40次，两组痊愈率及副反应差异无显性。结论：Q开关Nd:YAG激光倍频532／nm和585nm两种波长对密度较低、直径较细的面部毛细血管扩张均有可靠疗效，术后除色素沉着发生较高外，其他不良反应较少。     

Seasonal covariation of the circadian phases of rectal temperature and slow wave sleep onset

There is a scarcity of well-controlled studies of the seasonal variation in circadian rhythmicity. In the present study, the circadian phase of rectal temperature and the onset of slow wave sleep were studied in a series of twelve 24-h experiments, one each month of the year, for six healthy subjects under controlled conditions in a climatic chamber. In winter, as compared with summer, the average circadian rhythm of rectal temperature was phase delayed by 45 min, and the average onset of slow wave sleep was phase delayed by 40 min. The temporal relationship between the circadian phase of rectal temperature and the timing of slow wave sleep was maintained throughout the year. Habitual rising and retiring times covaried as well. Furthermore, the circadian rhythm of rectal temperature followed the timing of the photoperiod across the year, but had a much smaller range of seasonal variation. Apparently, the seasonal variation in the photoperiodic zeitgeber is largely compensated for by the stabilizing influence of secondary zeitgebers. However, in healthy subjects some effect of photoperiodic variation can still be observed.     

Fluid shear induced endothelial cell detachment from glass - influence of adhesion time and shear stress

In this study, human umbilical vein and human saphenous vein endothelial cells were seeded on glass and exposed to fluid shear in a parallel-plate flow chamber. Cell retention, morphology and migration were studied as a function of shear stress and of adhesion time prior to exposure to shear. Three-hour and 24-h adhesion times gave rise to comparable cell retention values after 2 h of flow for both cell types. Cell retention decreased from 85 to 20% as shear stress increased from 88 to 264 dynes cm⁻² (8.8 to 26 Pa). Mean spreading areas decreased after the onset of flow, but subsequently stabilized to plateau values, which were smaller at higher shear stresses. Shape factors increased faster to higher values as cells were exposed to higher shear stresses, without any obvious preference in orientation of the cells with respect to the direction of flow. Migration was unidirectional with flow and linear with time. Migration was faster for cells which had adhered for 24 h than for cells which had adhered for 3 h and was accompanied by the presence of fibrillar structures left behind on the surface upstream of migrating cells. It is concluded that after 3 h adhesion to glass, cells have adhered with an adhesion strength that does not substantially increase during the next 21 h. However, during this time changes in cell-substratum interactions seem to occur judging by the differences in, e.g., migration rates.     

氟乙酰胺的极谱测定法

目的建立微量氟乙酰胺的极谱分析法。方法应用氟乙酰胺在高温强碱条件下的分解反应,利用极谱法对其分解产物形成的ALC-La-F-三元络合物在pH=4.90的含KNO3的六次甲基四胺缓冲液中的-0.67V处的络合物吸附波进行测定。结果在所选定的最佳条件下,氟乙酰胺的线性范围为5.0×10-8～1.2×10-6mol/L,回归方程y=3.49x+0.042,相关系数r=0.9996,方法的检测下限为2.0×10-8mol/L。结论该法可用于测定面粉中的氟乙酰胺。     

超声诊断甲状腺腺瘤与单发结节性甲状腺肿的价值

目的　探讨超声在甲状腺腺瘤与单发结节性甲状腺肿鉴别诊断中的价值。方法　对两种疾病的二维及彩色多普勒声像图进行分析并比较。结果　甲状腺腺瘤与单发结节性甲状腺肿比较 ,甲状腺大小、结节大小、结节内回声及周围回声组间差异均无统计学意义 (P >0 .0 5 ) ;结节边缘晕环及结节内部和周边血流信号差异有显著性 (P <0 .0 5 )。结论　单发结节性甲状腺肿易误诊为腺瘤 ,结节边缘晕环及结节内部和周边血流信号对鉴别诊断可提供帮助     

Randomized, placebo-controlled, double-blind clinical trial evaluating the treatment of plantar fasciitis with an extracoporeal shockwave therapy (ESWT) device: a North American confirmatory study.

Despite numerous publications and clinical trials, the results of treatment of recalcitrant chronic plantar fasciitis with extracorporeal shockwave therapy (ESWT) still remain equivocal as to whether or not this treatment provides relief from the pain associated with this condition. The objective of this study was to determine whether extracorporeal shock wave therapy can safely and effectively relieve the pain associated with chronic plantar fasciitis compared to placebo treatment, as demonstrated by pain with walking in the morning. This was set in a multicenter, randomized, placebo-controlled, double-blind, confirmatory clinical study undertaken in four outpatient orthopedic clinics. The patients, 114 adult subjects with chronic plantar fasciitis, recalcitrant to conservative therapies for at least 6 months, were randomized to two groups. Treatment consisted of approximately 3,800 total shock waves (+/-10) reaching an approximated total energy delivery of 1,300 mJ/mm(2) (ED+) in a single session versus placebo treatment. This study demonstrated a statistically significant difference between treatment groups in the change from baseline to 3 months in the primary efficacy outcome of pain during the first few minutes of walking measured by a visual analog scale. There was also a statistically significant difference between treatments in the number of participants whose changes in Visual Analog Scale scores met the study definition of success at both 6 weeks and 3 months posttreatment; and between treatment groups in the change from baseline to 3 months posttreatment in the Roles and Maudsley Score. The results of this study confirm that ESWT administered with the Dornier Epos Ultra is a safe and effective treatment for recalcitrant plantar fasciitis.     

体表电位标测微机系统(Ⅰ型)

本系统的107个电极中,103个分布于胸、背部,1个为参考电极,1个为V_3,其余用于肢导。本系统除能绘出2、4、8ms任意间隔的103通道同步的体表等电位图,常规12导联和V_(7 9)心电图,胸、背部位的心电图外,还可记录R峰值等电位图,∑R,Q波等电位图,nQ30、40,极大、极小轨迹图等。     

Lithium increases slow wave sleep: possible mediation by brain 5-HT2 receptors?

The effect of lithium on slow wave sleep (SWS) was studied in ten normal male volunteers using home based cassette sleep recording and automatic sleep stage analysis. Lithium increased SWS, an effect consisten with a reduction in brain 5-HT₂ receptor function.