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Comprehensive and designed experiment is beneficial to improving and developing students' comprehensive quality and innovation ability.In the last two years,we have carried out the comprehensive and designed experiment of physiology among the seven-year program students,which combine book knowledge and clinics.It has proved that this teaching mode can not only help students master the knowledge systematically but also lay a good foundation for them to analyze the clinical problems.
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Objective: To study the effects of TNFα on wound healing. Methods: The skin lesion and incisions were made on mice and rhTNFα was applied in both skin lesion and incision. Tissue strips were evaluated for tensiometry and histologic features after healing. Results: It was found that rhTNFα markedly improved wound healing both in skin lesion and incision wound model, it also markedly enhanced the breaking strength of treated incision and increased wound cellularity in rh TNF α treated groups. Conclusion: The results suggest that TNFα play an important role in regulating inflammatory reactions of local injured tissues and it may improve the functions of fibroblasts, mononuclear phagocytes and endothelial cells. rhTNFα of suitable doses can promote wound healing. This shows that TNFα, as a wound healing promoter, has the potentials for clinical application.
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Objective: To find out the pathomechanism of low back and leg pain related to intervertebral disc. Methods: The nucleus pulposus of coccygeal vertebral was transplanted to the cavum epidurale of rats to establish the non-compressive model with transplanted nucleus pulposus. The evoke potentials and morphology of nerve roots were observed. Results: Even without mechanical compression, rats transplanted with nucleus pulposus resulted in significant harm to evoked potential and morphology of cauda equina. Conclusion: The biomechanical and/or immunologic inflammatory effect of nucleus pulposus can result in nerve roots injury and is an important factor in the pathogenesis of low back and leg pain.
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Objective:To study the role of phospholipase A 2 in the pathomechanism of low back and leg pain. Methods:Phospholipase A 2 was injected into rats′ cavum epidurale, then the pathologic changes of cauda equina was viewed under light microscopy and electronic microscopy. The substance P(SP) in the dorsal root ganglia(DRG) and spinal cord was determined by immunohistochemistry. Results:After phospholipase A 2 injection, the nerve fibers of cauda equina displayed significant degeneration and demyelination. In L 4 to L 6 segment, the number and area of SP positive neurons in the DRG increased significantly. The relative density of positive nerve endings in the dorsal horn of spinal cord was also increased significantly. There were significant difference compared to the normal solution control group by statistic analysis. Conclusion:Phospholipase A 2 is a nocuous substance to cauda equina. It may play an important role in the pathomechanisms of low back and leg pain related to lumbar disc herniation.
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Objective: To investigate the effect of N methyl D aspartate(NMDA) on cochlear potentials and to find out the possible neurotoxic effect of NMDA on cochlea function in guinea pigs. Methods: After basal compound action potentials (CAP) and cochlear microphonics (CM) were recorded by round window electrode, animals ( n =5) were treated with Hanks applied to the round window membrane (RWM) for 20 min as control. Then 100 ?mol/L NMDA was applied to the RWM for another 20 min. Results: Hanks produced no obvious changes in CAP threshold, CAP N1 and CM latency and amplitude. CAP thresholds at all frequencies of tone burst were significantly elevated by application of NMDA, threshold shifts ranged from 13 27 dB. NMDA significantly reduced the CAP N1 amplitudes at all intensities of stimulations. CAP amplitudes were suppressed by 50% 75%. NMDA also significantly increased the CAP latency, the latency of CAP evoked by 6 kHz tone burst at intensity of -90 dB(output attenuation) was (1.9?0.06) ms after Hanks treatment and (2.76?0.21) ms after NMDA treatment ( P
Résumé
In 34 hypothalamic slices of rats, spontaneous discharging of 63 paraventricular neurons was extracellulariy recorded by glass microelectrode. When the slices were perfused with artificial cerebrospinal fluid (ACSF) containing noradrenaline (NA) (10-6 mol/L), firing rates of 20 units significantly increased, those of 8 units decreased or even ceased, and those of 35 units, not affected. When low Ca2+ high Mg2+-ACSF was applied to block synaptic transmission, of 20 units which were excited by NA, 14 units still had excitatory responses and 6 units had no significant response to NA. When synaptic transmission was blocked, of 8 units which were inhibited by NA, 7 units still had inhibitory responses and only one unit had no significant response to NA. The results of this experiment strongly suggest the existence of direct effects of NA on paraventricular neurons.