The evoked spinal potentials (ESPs) of cats were observed in this experiment. 29 animals weighing 2 to 3.5kg were Used, and divided into three groups:I, control and general observations; II, acute contusion of spinal cord; III, spinal cord compression and decompression. In each mode of trauma. the intensity of traumatizing factor included three different levels.The normal lumbar segmental ESPs consist of two predominant components: N1 and N2 wave, within the first 20 msec after stimulation artefact. Preceding to N1 was a positive wave P1. From a series of tests, it was suggest N1 is related to the activity of dorsal part of cord and N2 is related to the activity of dorsal as well asventral part of cord.After the transection of spinal cord at L4-5, the ESPs recorded rostral to that site disappeared and were replaced by a single positive wave, the so called "killed end" potential.Immediately after cord contusion, the P1-N1 components of ESPs of traumatized portion disappeared and were replaced by a single positive wave, and simu-1 tenously, the N2 diminished or flattend. If the impacting energy level was lower, the N1 or both N1 and N2 reappeared, and gradually increased their amplitude with the improvement of peak latency of N1 which was abnormally prolonged in the earlier hours of recovery.During cord compression both N1 and N2 of ESPs at the compressed portion decreased their amplitude with the peak latency of N1 prolonged. N2 disappeared earlier than N1 and finally only a single positive wave was left. If the compression time was shorter, both N1 and N2 might reappear after decompession, and the trend of recovering their original amplitude and peak latency was shown.Data proved that changes of ESPs may be used as the indicator of the viability of the traumatized spinal cord. The transient disappearance of ESPs would not indicate that the cord function coud not get recovery. On the other hand dying out of ESPs for several hours or even longer might reflect the serious-damage of cord function.The results of this experiments also suggested that N1 and N2 have different implications in reflecting the mechanisms of injuries.

Based on the analysis of anatomic, biomechanically experimental materials and clinical cases of wrist injuries between 1978 to 1982 in Changzheng Hospital, a general biomechanical concept about the function of proximal carpal row (PCR) and the significance of PCR to the wrist injury is established. An investigation of the kinematics and dynamics of the scaphoid was particularly conducted so that a rationale about which wrist posture is the best one on externally fixing the limb with scaphoid frac-ture was presented.

Objective To observe the inhibition effect of recombinant human monocyte chemoattractant protein－ 1(MCP－ 1) on implantation and growth of human osteosarcoma cells. Methods The method of protein fusion was used for the expression of MCP－ 1 in b.coli and then the MCP－ 1 was extracted and purified. Fifty nude mice were divided into 10 groups. For A1－ 4 groups, the 5 mice in each group were locally injected with doses of 1? g, 10? g, 100? g, 1 mg of MCP－ 1 at the same time when 4.4? 106 osteosarcoma cells were implanted in vivo. For B0－ 4 groups, 5 mice in each group, the injection were given 2 weeks later when there was the formation of the tumor mass at doses of 0? g(0.2 ml normal saline), 1? g, 10? g, 100? g, 1 mg of MCP－ 1 every other day. Five mice in group C were injected with dose of 0.2 ml NS as control. Results Implantation of osteosarcoma cells were completely prevented among mice of group A2－ 4, tumor inhibiting effect even in group A1 and the rate of tumor inhibition was 69.69％ . AKP values in mice of group A1－ 4 were much lower than those of group B0(P

BACKGROUND: In recent years, the method of bladder reconstruction is still at the experimental stage. Therefore, anatomical study is necessary for its clinical application.OBJECTIVE: To provide anatomical bases for the selection of proper spinal roots, the ideal level for cross anastomosis, and the identification of anterior roots of spinal nerves during bladder functional reconstruction with Achilles tendon reflexes.DESIGN: It was a single sample study with anatomical specimen as subjects.SETTING: The experiment was conducted in the department of orthopaedics of a municipal hospital.PARTICIPANTS: The experiment was completed in the Department of Anatomy, Second Military Medical University of Chinese PLA, from May 1999 to January 2000. Altogether 20 adult corpse specimens (14 males and 6females, 40 sides) were involved.INTERVENTION: The origin of spinal roots of the sacral plexus and sciatic nerve, the distribution of corresponding spinal root between the sciatic nerve and other nerves were followed up.MAIN OUTCOME MEASURES: Overlapping length, horizontal area, and relative position of anterior roots of L4-S4 spinal nerves in the dura mater.of S2 -4 anterior spinal roots originating from the spinal cord was higher than that of L4, L5 and S1 anterior spinal roots running through the dura; the cross-sectional area of L4(2. 19 ±0.39) mm2, L5(2.58 ±0.58) mm2 and S1(2.19 ± 0.42) mm2 anterior spinal roots was more than that of S2-4 anterior dentify their sequence at the terminal cone level than under this level.should be taken during bladder functional reconstruction with Achilles tendon level.