苏乐康等抑制细胞转化能力及其机制的探讨

研究了苏乐康、绿茶提取物对~(60)钴γ射线和雌性激素联合诱发叙利亚金黄地鼠胚胎细胞恶性转化的抑制能力,并用脉冲辐解技术,对其抑制机制进行初步探讨。实验结果表明,苏乐康、绿茶提取物对γ射线和雌性激素联合诱发的金黄地鼠胚胎细胞恶性转化的抑制率分别为70.15％(P<0.05)和81.59％(P<0.05),它们的这种抑制能力与其清除超氧阴离子的能力有关,     

Nonlinear excitation profiles for three-dimensional inflow MR angiography

An RF excitation pulse for three-dimensional (3D) time-of-flight (TOP) MR angiography (MRA) with a nonlinear excitation profile was numerically calculated under the condition of uniform vessel signal across the excitation volume (slab), and the superiority of the optform pulse as compared with conventional RF pulses and TONE pulses was demonstrated. For this purpose we acquired MRA of the lower leg and of the carotid and vertebral arteries in a 30-year-old healthy volunteer. Although the flow velocity ranges in these two anatomic locations are different by about a factor of 10, in both cases the corresponding optform pulse provided the best signal homogeneity at the highest level.     

Human imaging of phosphorus in cortical and trabecular bone in vivo.

Phosphorus was imaged in vivo in human cortical and trabecular bone and the T(1) and T(2) (*) were measured. An ultrashort TE (UTE) pulse sequence (TE = 70 microm) was used with half pulse excitation and radial mapping of k-space from the center out. T(2) (*) was measured using multiple echo times and T(1) was measured both by saturation recovery and by a method using different RF pulse amplitudes. Seven normal subjects (32-85 years) were examined. Phosphorus was imaged, with a true in-plane resolution of 2.9 x 2.9 mm and a signal-to-noise ratio (SNR) of 19:1, in both cortical and trabecular bone. The mean T(2) (*) value was 207 +/- 12 micros, and the mean T(1) value was 8.6 +/- 3.0 sec. Images and measurements were obtained in realistic times on a clinical MR system. This may provide a new approach to characterizing disease of bone.     

42.3GHz毫米波电场治疗大鼠脊髓损伤的实验研究

研究毫米波对损伤脊髓修复的生物效应。方法采用频率４２．３ＧＨｚ，波长７．１ｍｍ，同功率密度２ｍＷ／ｃｍ＾２，７ｍＷ／ｃｍ＾２，２０ｍＷ／ｃｍ＾２的毫米波治疗大鼠损伤脊髓，３０ｍｉｎ，２次／ｄ＊２０，观察组织学及皮层体感诱发电位、运动诱发电位变化。     

Detection of Human Heart Rate in Exercises State

作者介绍了一种动态心率检测电路，它能准确、可靠地检出在运动状态下的人体心率。电路采用两种检测技术，一种为双时值ＱＲＳ波检测法，另一种为光电脉搏检测法。     

细脉者左心室舒缩功能的研究

采用超声心动图对43例细脉者左心室舒缩功能进行了检测,并以26例滑脉和30例平脉作为对照组,发现细脉者8项左心室舒缩功能指标与各对照组比较有非常显著性差别(P>0.01)。说明细脉者具有左心室收缩功能和舒张功能的异常.左心室舒缩功能的减退是细脉产生的重要原因之一。不同原因的细脉者左心室舒缩功能的差别无显著性(P>0.05),揭示不同原因的细脉其产生的机理存在着同一性。     

Microalbuminuria and nerve conduction velocity in type-I diabetics during conventional therapy and during continuous I.V. insulin infusion

Summary The objective of this study was to follow the development of microalbuminuria and nerve conduction velocity under continuous i.v. insulin therapy over a limited period of 4 months. For this purpose, 8 labile type I diabetics were selected (age 33±8 years, duration of diabetes 16±9 years) and treated conventionally with two insulin injections daily over 4 months. Afterwards, the same patients were treated with continuous i.v. insulin infusion and finally again with two injections daily over 4 months each. This procedure allowed each diabetic to serve as his own control. HbA₁, microalbuminuria, nerve conduction velocity and relative refractory period of the ulnar nerve were checked at montly intervals. During the continuous i.v. infusion over 4 months, blood sugar values were significantly lower, glucosuria had disappeared almost completely and the glycosylated hemoglobin had fallen to near normal values. The mean rate of albumin excretion was 16±5 μg/min at rest and 76±26 μg/min during exercise (normal: 3.9±0.4 and 4.8±1.2 μg/min, respectively) and did not change significantly. Nerve conduction velocity in the ulnar nerve rose significantly under i.v. insulin therapy from 47.9±0.6 m/sec to 52±0.6 m/sec. Similarly, the relative refractory period of the same nerve fell significantly from 3.7±0.2 to 1.9±0.1 msec (i.e. to within normal range). It is concluded that functional disturbances of peripheral nerve can regress by improved blood sugar control with continuous i.v. insulin infusion over 4 months. On the other hand, incipient microangiopathy measured as microalbuminuria remains unchanged over the same period of time. If an improvement is at all possible, considerably longer periods of euglycemia are likely to be necessary. Supported by Grant No. 3.964-0.80 from the Swiss National Science Foundation.     

动脉波形分析计算心排出量及临床应用

动脉波形分析技术用于测量心排出量(arterial pressure-based cardiac output,APCO)和每搏输出量变异指数(stroke volume variation,SVV)是一项新的微创血流动力学技术,它能够连续通过对外周动脉的波形特征结合患者的基本信息(年龄、性别、身高、体重等)进行分析测定心排出量(CO),并且不需要通过其他方法来校准.临床上已经显示出可以接受的准确性和良好的即时性和方便性,但也存在一定的局限性,如在一些心脏疾病如主动脉返流、二尖瓣返流或给予α1受体激动药,APCO并不能准确反映心排血量.     

体外冲击波对兔输尿管形态及组织学影响的研究

目的 :探讨冲击波 (SW )对输尿管形态的影响。方法 :将 4 2只成年兔随机分为 7组 ,每组 6只。第 1组为正常对照组 ;第 2～ 6组为液电式SW组 ;第 7组为电磁式SW组。各组接受冲击并在冲击后不同时间取材。全部标本行常规病理检查并予评分。结果 :第 2～ 5组和第 7组 ,肉眼可见焦点周围组织有出血、水肿等改变 ,输尿管直径较冲击前显著增加 (P <0 .0 1 )。光镜下可见平滑肌细胞变性及管腔狭窄 ,病理量化评分显著高于正常组 (P <0 .0 5 ) ;电镜下则有肌细胞线粒体破坏等改变。第 6组形态改变不明显 ,病理评分和正常组的区别无显著性意义。结论 :临床剂量的冲击波能导致输尿管多种病理变化。冲击后第 5天 ,输尿管形态已基本恢复正常。由液电式和电磁式冲击波所致的输尿管急性损伤程度无明显的区别     

频闪喉镜对声带病理情况观察的研究

对1997年以来423例病态喉的频闪喉镜表现进行分析,结果显示声带有病理改变者其粘膜波、振幅、闭合相、运动周期性、对称性均有不同程度的变化,这种变化能直接反映声带病变的深度及范围,对喉部疾病的诊断、鉴别诊断、治疗指导及预后评价具有重要意义.