超短波治疗慢性肺源性心脏病患者的初步探讨

目的:探讨超短波对慢性肺心病CCP患者的临床应用价值。方法:急性发作期CCP患者87例分为超短波治疗组45例和对照组42例,治疗组在常规治疗的基础上给予超短波治疗,对照组行常规治疗。治疗前后分别测定两组患者血浆中血管内皮生长因子VEGF、内皮素(ET-1)含量,动脉血氧分压(PaO2)和平均肺动脉压(mPAP)水平。结果:与对照组比较治疗组治疗后PaO2显著升高(P<0.01),VEGF、ET-1、mPAP明显降低(P<0.01)。VEGF、ET-1与PaO2呈负相关(P<0.01)、与mPAP呈正相关(P<0.01)。结论:超短波可以通过降低肺动脉高压对CCP患者起治疗作用。     

Blood Flow and Leukocyte Adhesiveness Are Reduced in the Microcirculation of a Peritoneal Disseminated Colon Carcinoma

Dynamic behavior of leukocytes in the microcirculation of solid tumor tissue was visualized using a fluorescent labeling technique combined with the use of a real-time confocal laser-scanning microscope (CLSM) system. Colon tumor cells (RCN-9) were inoculated into the peritoneal cavity of male Fischer 344 rats. Tumor-free rats were similarly injected with physiological saline (intraperitoneally). Ten days after tumor inoculation, the mesentery was exteriorized and subjected to vital microscopic observation under the CLSM system. Leukocytes were labeled with rhodamine 6G (100 g kg^–1, intravenously), and their behavior within the microvessels (10–30 m in diameter) was analyzed both in the solid tumor tissues and the normal mesentery. Wall shear rate was calculated from the measured values of vessel diameter and erythrocyte flow velocity. In tumor microvasculature of tumor-bearing rats, the centerline erythrocyte velocity (0.73 ± 0.58 mm s^–1, mean±standard deviation) and wall shear rate (210 ± 151 s^–1 were significantly lower than those of the tumor-free rats (1.27 ± 0.83 mm s^–, 344 ± 236 s^–1, respectively). Despite such reduced flow conditions, flux of the rolling leukocytes as well as density of the adhered leukocytes both decreased significantly in tumor microvasculature as compared with normal controls. The methods developed in this work show promise in improving our understanding of tumor biology and pathophysiology. © 1998 Biomedical Engineering Society. PAC98: 8722Fy, 8745Hw, 8745Ft, 8764-t, 4262Be     

ESWL实际焦点位置的理论和数值分析

从理论和数值模拟两个方面分析了ESWL中的非线性的动力学焦点和实际焦点的位置 ,给出三种典型的动力学焦点的数值结果 ,说明非线性动力学焦点和实际焦点一般不是几何焦点 ,指出正确确定实际焦点在ESWL技术中的重要性。     

Effects of fluid flow on elution of hydrophilic modifier from dialysis membrane surfaces

When uremic blood flows through dialyzers during hemodialysis, dialysis membrane surfaces are exposed to shear stress and internal filtration, which may affect the surface characteristics of the dialysis membranes. In the present study, we evaluated changes in the characteristics of membrane surfaces caused by shear stress and internal filtration using blood substitutes: water purified by reverse osmosis and 6.7 wt% dextran70 solution. We focused on the levels of a hydrophilic modifier, polyvinylpyrrolidone (PVP), on the membrane surface measured by attenuated total reflectance Fourier transform infrared spectroscopy. Experiments involving 4 h dialysis, 0-144 h shear-stress loading, and 4 h dead-end filtration were performed using polyester-polymer alloy (PEPA) and polysulfone (PS) membranes. After the dialysis experiments with accompanying internal filtration, average PVP retention on the PEPA membrane surface was 93.7% in all areas, whereas that on the PS membrane surface was 98.9% in all areas. After the shear-stress loading experiments, PVP retention on the PEPA membrane surface decreased as shear-stress loading time and the magnitude of shear stress increased. However, with the PS membrane, PVP retention scarcely changed. After the dead-end filtration experiments, PVP retention decreased in all areas for both PEPA and PS membranes, but PVP retention on the PEPA membrane surface was lower than that on the PS membrane surface. PVP on the PEPA membrane surface was eluted by both shear stress and internal filtration, while that on the PS membrane surface was eluted only by internal filtration.     

Differential effects of two types of environmental novelty on activity and sleep in BALB/cJ and C57BL/6J mice

Change in the sleeping environment can produce significant alterations in sleep. To determine how these alterations may vary with the amount of change and the relative reactivity of the sleeper, we examined the influences of environmental novelty on sleep in two mouse strains that differ in behavioral anxiety. Mice [BALB/cJ (n=7) and C57BL/6J (n=8)] were implanted for recording EEG and activity via telemetry. Following baseline data collection, activity and sleep were examined over 46 h after routine cage change, after placing a simple novel object (PVC Tee) in the home cage, and after handling controls. Mice of both strains showed immediate increases in activity and decreases in rapid eye movement sleep (REM) and non-REM (NREM) after cage change and novel object. Within strain, changes in activity and sleep were greater after cage change than after novel object. Changes in activity and sleep time were significantly correlated in each strain. Compared to C57BL/6J mice, BALB/cJ mice exhibited greater and longer duration initial reductions in sleep time, and greater increases in EEG slow wave activity power after cage change and novel object, but these changes were not followed with subsequent increases in sleep time. In contrast, C57BL/6J mice showed significantly greater subsequent increases in sleep time following the initial reductions induced by both manipulations. The results suggest that initial decreases and subsequent increases in sleep time are related to putative differences in the intensity of environmental novelty (cage change>novel object) and to previously described strain differences in anxiety (BALB/cJ>C57BL/6J).     

Matched adaptations of electrophysiological, physiological, and histological properties of skeletal muscles in response to chronic hypoxia

This study tried to differentiate the consequences of chronic hypoxia on the electrophysiological and physiological properties and the histological characteristics of slow and fast muscles in rats. Animals inhaled a 10% O₂ concentration for a 1-month period. Then, slow [soleus (SOL)] and fast [extensor digitorum longus (EDL)] muscles were analyzed in vitro by physiological and electrophysiological measurements and histological analyses. The results were compared to those obtained in corresponding muscles of an age-matched normoxic group. After exposure to hypoxia: (1) in SOL, there was a tendency to elevated F_max, a significant increase in twitch force and tetanic frequency and a shortening of M-wave duration, and a reduced percentage of type I fibres, whereas the proportion of type IIa fibres doubled; (2) in EDL, F_max and tetanic frequency were lowered, the muscle became less resistant to fatigue, and the proportion of type IId/x fibres was halved. Then, after 1 month of hypoxia, in the SOL muscle, both the contractile and histological properties resemble those of a fast muscle. By contrast, the EDL became slower, despite its histology was modestly affected. Reduced muscle use in hypoxia could explain the tendency for deteriorating adaptations in EDL, and the faster properties of SOL could result from hypoxia-induced inhibition of the growth-related fast-to-slow shift in muscle fibre types.     

神经脉冲波传播形态的研究

Hodgkin-Huxley模型（H—H模型）是研究神经电生理不可或缺的数学依据。但是，到目前为止，对H—H神经元模型的分析缺少解析研究。本文对经典的H-H模型进行具体分析，得到简化H—H模型以及Nagumo方程，利用齐次平衡方法首次求出简化H-H方程和Nagumo方程的孤波解。研究表明：神经冲动可以孤波的模式传播。     

Ambient temperature related sleep changes in rats neonatally treated with capsaicin

Ambient temperature related sleep changes in rats neonatally treated with capsaicin. PHYSIOL BEHAV 00(0) 000-000, 2004. The study was conducted on adult male Wistar rats, neonatally treated with capsaicin to destroy the peripheral warm receptors. The sleep-wakefulness was recorded for 5 h at an ambient temperature (T(amb)) of 18, 24, 30 and 33 degrees C on different days. The rectal temperatures (T(r)) of the rats were studied on exposure to 6 and 37 degrees C for 2 h to assess their thermoregulatory ability. The changes in the behavioral thermoregulation were assessed by noting the thermal preference of rats when they were placed in an environmental chamber with 3 interconnected compartments maintained at 24, 27 and 30 degrees C. Slow wave (SWS) and rapid eye movement (REM) sleep were decreased at 18 degrees C and increased at 30 degrees C, in control rats. There was a decrease in REM sleep and no change in SWS when T(amb) was raised from 30 to 33 degrees C. However, in neonatally capsaicin treated rats, sleep was increased even at 33 degrees C, though there was no significant change in sleep when T(amb) was increased from 18 to 24 degrees C. Capsaicin treated rats showed thermoregulatory deficiency at 37 degrees C but the thermal preference was unaltered in these rats. The results suggest that the central warm receptors can produce alteration in sleep at different T(amb), even in absence of peripheral warm receptors. The behavioral thermoregulation was unaffected in these rats, though their ability to defend the body temperature in warm environment was affected.     

Parabrachial neuron discharge in the cat is altered during the carbachol-induced REM sleep-like state (DCarb)

Pontine parabrachial neurons have been suggested to play a regulatory role in both respiratory and sleep cycle control. Encouraged by the finding that microinjections of the cholinergic agonist carbachol into the medial pontine reticular formation (mPRF) of the cat produced respiratory changes paralleling those observed during rapid eye movement (REM) sleep (Neurosci. Lett., 102 (1989) 211–216), this study tested the hypothesis that cholinergic mechanisms in the mPRF can also cause state-dependent changes in the discharge of parabrachial neurons. This paper describes extracellular recordings of parabrachial neurons during REM sleep and during the carbachol-induced REM sleep-like state (DCarb). Cells which were activated (REM-on) or inactivated (REM-off) during REM maintained these same state-dependent firing patterns during the DCarb state. These results support the hypothesis that cholinergic mechanisms in the mPRF can cause state-dependent changes in the discharge of parabrachial neurons.