The experiment was earied out on the a boomen of the whiterats. The epigastric vein wasarterialized by means of anastomcois with the femoral artery, lateral thoracic vein was reserved as aefferent vessel. The changes of hemorheology were mesured after arterialization, and were comparedwith the changes in the normal A-V skin flaps. The levels of platelet, aggreation, blood viscosityand plasma fibrinogen in arterialized vein flape were signmeantly higher than that in A-V flaps. ASa r...
It was reported that the systemic use of phenytoin could promote healing of fracture. In order to observe the effect of local application of phenytoin in the healing of fracture, the experiment was performed. Seventy-two rabbits were divided into three groups. Fractures were created on both radius of all rabbits. Group 1, intraperitoneal injection of phenytoin with a dosage of 50 mg/kg per day; Group 2, local use of phenytoin with a dosage of 40 mg/kg was injected in the fracture site every seventy-two hours, and Group 3, injection mormal saline of in the control group. Eight rabbits in each group were sacrificed in the 9th, 16th and 30th days after operation respectively. By X-ray excuiualtion, the healing of fracture was observed. Dry and wet weights of the callus were determined. After HE and Mallory’s stain, the samples were examined under microscope. Results showed that both local and systemic use of phenytoin promoted healing of fracture. The effects of phenytoin in the two groups were the same and had no significant difference.
This experiment consisted of removing a segment of femoral artery measuring 3cm from Japanese white rabbits. The arterial segments were divided into 3 groups and grafted as homograft at different periods of time. The segments in group 1 were grafted immediatly after their removals, those in the group 2 and group 3 were stored at -30 and -196 degrees centigrade before grafting, respectively. The results from gross and histological examinations, it was noted that following deep freezing the long term patency rate after grafting of the arterial homografts was superior to those not undergoing deep freezing. Those stored at 30 degrees centigrade for 12 weeks had the lowest patency rate.
Abstract An animal experiment had been conducted for the purpose to find out the possibility of application of instantaneous sustained limited expansion (ISLE). A total of 54 skin defects in 9 pigs were obtained and were divided into two groups. One group of the pigs were subjected to instantaneous sustained limited expansion, the others, as the control group, just received the tension suture. At the same time the blood supply of the skin was measured by laser doppler flowmeter (LDF). It was showed that microcirculatory perfusion of the ISLE group was considerably better than that of the control. Inaddition, the correlation between the blood flow of the skin and the expanding pressure, as well as the pathologic changes of the skin were discussed.
Abstract In order to find a new method to repair large bone defect, the free periosteum autograft was investigated in experiment, and then the method was used clinically. In the experiment, a 6mm×18mm×5mm bone defect was made at upper end of both tibiae of 42 rabbites. The periosteum of each rabbit was cut into 1mm cubes, and implanted randomly into the tbial bone defect on one side and the other side was used as control. After 2, 4, 8 weeks, the bone defects of each group were examined for bone formation by roentgenography, radionuclide and histology. The results showed that the defects treated by free periosteum autografts healed twice as fast as the controls (its natural healing). The reason probably was that the periosteum provided with many osteogenic cells. On thebasis of these results, 21 cases of bone defects (the largest was 10.5cm×4cm×4cm, the smallest was 2cm×2cm×2cm) including 17 cases of benign bone tumor and4 cases of chronic osteomyelitis, were treated by free periosteum autografts. The defects were all healed, and the function of the joints was restored.
Local hypothermia as a preventive method to reperfusion injury of skeletal muscles was studied. Sixteen Japanese rabbits were divided into four groups at random. Before the tourniquet was inflated, a cold gel pack was applied to the right hind leg of each rabbit for 15 minutes to produce local hypothermic condition, without application of tourniquet the left hind limb was under local hypothermic condition as a control. The duration of tourniquet ischemia was 4 hours, and then reperfusion for one and two hours in the A and B groups respectively; in the C and D groups the duration of ischemia was 5 hours, and reperfusion for one and two hours, respectively. The muscle temperature averaged 16.6 degrees C with a needle thermocouple in the hind limb under local hypothermia. The serum K+, LA, SOD, LPO were determined from bilateral femoral veins, and electron and light microscopic studies of sural muscles were done in the post-reperfusion period. It was found that the K+, LA, LPO were lower than that of the control groups (P lt; 0.01), but SOD was higher than that of the control group (P lt; 0.01). Electron and light microscopic studies showed sight but reversible damage of muscular structure with the possibility of in the hypothermic groups cell regeneration. Basing on this experimental results, this method was applied in 45 cases reparative and reconstructive surgery of limbs. The duration of application of tourniquet averaged 2 hours and 57 minutes, the longest being 4 hours and 31 minutes, when the muscle temperature had reduced to 22.4 degrees C. There were no postoperative complications associated with this technique. Local hypothermia appeared to be a safe and effective method of decreasing the reperfusion damage after ischemia.
Motor endplate is the structure connected between the nerve terminal and muscle fibre and plays a very important role in conducting nerve impulses to the target, therefore, systemical study of the sequential changes of the motor end-plate upon denervation is quite important.Ninety New Zealand rabbits were divided into nine groups from two weeks to nine months after denervation. Acetycholinesterase(AchE) was analyzed quantitatively to study the sequential changes of the motorendplates of tibialis anterior muscle. The results showed that there was no significant reduction of AchE at theend if one month after denervation, whereas a sharp reduction of AchE afterwards. AchE could not be stained after five month denervation.
OBJECTIVE To investigate the effect of meniscus suture on meniscus healing which included healing time and healing pattern. METHODS Fourty healthy rabbits were adopted in this study. The model of meniscus injury was made by a longitudinal incision at the medial meniscus of the left knee. The rabbits were divided into two groups, the experimental group was treated by meniscus suture and the control group was unsutured. After operation, the meniscus samples were collected periodically and observed by gross, light and electronic microscope to analysis the meniscus healing. RESULTS The injured meniscus was healed gradually and completely at the sixth week in the experimental groups. More fibroblasts and less fibrocartilage cells could be observed in the healed meniscus. Oppositely, there was no meniscus healing in the control group and the edge of injured meniscus was sealed by epithelioid cells. CONCLUSION The meniscus suture can accelerate the healing process of meniscus injury. Besides, early suture make the injured meniscus correctly positioned to ensure the normal healing process.
To study the blood supply and revascularization of super thin skin flaps with a presserved subcutaneous vascular retwork , we carried out a randomized self-matched experimental study in 10pigs. The free skin grafts with a preserved subcutaneous vascular network served as control. All skingrafts and flaps were divided into 6 groupe, besed on the potoperative days (1st , 3rd, 5th , 7th , 10thand 14th day). The revascularization of flape were assessed by means of intravenous fluorescein test...
Abstract In order to study the influence of chitosan on bone infection, 27 New-Zealand rabbits were randomly divided into 3 groups. According to the Norden technique, the model of osteomyelitis of the tuberosity of tibia was produced experimentally by injection of staphylococcus aureus.Immediately following injection of the staphylococci, the chitosan gel, acetic acid solution and sterile distilled water were injected into the bones in the 3 groups respectively. The latter two groups were served as control. The severity of the infection was evaluated by clinical symptoms and signs, radiographicdata as well as the bone culture and bacterial counts. Compared the results from chitosan with the other two controls, it was found that the local injection ofchitosan could not reduce the incidence of bone infection, however, it could provide actual improvement when other data were concerned. The effects of chitosangel might be attributed to its bacteriostatic and immunological activity as well as its slow degradation in the body.