Using 70 SD white rats, diveded in two groups at random, after the common carotid artery wa(?) exposed, anastomosis of the artery was done by whole-layer suture and suture without including the endothelial layer, respectively. The rate of patency of both groups immediately after operation was 100 percent, where as in late stage, 94 percent and 97 percent, respectively. From the histologic exam ination, it was found that in the group of whole-layer suture, the time required to cover the sutureline with endothelium was delayed and there was rupture of the clastic fibers.
An in vitro experiment showed that the skin expanders were permeable to metronidazole and procaine. Twenty kidney shaped skin expanders were divided into four groups. Group 1. 100ml 0.2% metronidazole solution was injected into the expanders and the expenders were immersed in a flask filled with 100ml saline solution, and then were placed in a hermetically sealed glass chamber; Group 2.the whole procedure was the same as that of Group 1 except the expander was previously boiled in water for 30 minutes; Group 3. 100 ml 2% procaine was injected instead of metronidazole, other step was the same as that ofgroup I; and Group 4. the whole procedure was the same as that of Group 2 except the solutioninjected was 2% procaine. The concentration of metronidazole and procaine in the surrounding saline was measured at 1st, 2nd, 4th, 16th, 24th, 48th, 72nd 120th hours. The rate of diffusion of a drug was highest at 2 and 4 hous. The rate of diffusion was inversely proportional to its molecular weight, i.e., the smaller the molecular weight the greater the permeability. In view of this, during the process of expansion, metronidazole and procaine would diffuse out of the expander which might be beneficial for preventing infection and controlling pain.
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.
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.
The aim of this experiment was to study the osteogenesis in vivo of allogenic osteoblast combined culture with calcium phosphate composites. The osteoblasts were obtained by enzymatic digestion of periosteum from fibula subcultured to 13 generations, the cells were combined culture with hydroxyapatite and biphasic calcium phosphate. Subseguently, the composite was implanted into rabbits subcutaneously or intramuscularly. The blank material was implanted in the contralateral side as control. Four weeks later, all animals were sacrificed. All the implants were examined by gross observation, histological examination and EDXA. The results showed: 1. obvious ingrowth of connective tissue with very little inflammatory reaction; 2. new bone formation in the composites with deposit of Ca and P on the surface of osteoblast, but none in the blank materials; 3. no significant difference of new bone formation between the different sites of implantation or different materials, but those implanted intramuscularly had lamellae form of new bone while those implanted subcutaneously had only mineralization of extracellular matrix. The conclusion were: 1. the composites are biocompatible with prior osteogenesis property; 2. periosteal-derived allogenic osteoblasts obatined by enzymatic digestion could survive following implantation with bioactivity; 3. rich blood supply might be advantageous to new bone formation and its maturation.
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.
In this experiment, two proximal ends of themedian and ulnar nerves of rabbit wereapproxirnated within the chitin tube for thepurpose to inhibit the neuroma formation. Byobservation under light and transmission electronmicrnscopo and immunohistochemistry, wefound that: (1) the axons of the two proximalstumpe could regenerate in the chitin tube for 2to 5mm, and then ceased to grow when anaxonal overlap happened resulting in inhibitingneuroma formation; (2) chitin tube could bedegradated a...
This experiment was to study the blood supply of diffcrent types of skin flaps and the revascularization of the host region. The types of skin flaps used in this cxpcriment were the axial pattern flap and the random pattern flap on the back of rabbite. Forty New Zealand rabbits were divided into 5 groups at random. In gathering the data For assessment, besides the local changes such as color, swelling of the flaps, the area of survival of flaps after division of the pedicles, the tests used to observe the postoperative changes included the isotope (99mTc) clearance test, intravenous orescein test, tissue transparent method by perfusion of the flap vessels with Chengdu ink and histologie study. The following conclusions cule be drawn: The complete revaseularization of random pattern flap occurred at 10 days after operation and that of xaial pattern flap was 14 days, the random pattern flaps had a quicker rate of revascularization. It was suggested that the flap ischemia was a factor which enhanced revascularization.
ObjectiveTo investigate the feasibility of magnamosis rings designed based on magnetic compression technique in esophageal anastomosis reconstruction.MethodsAccording to the anatomical characteristics of esophagus in SD rats, the esophageal magnamosis rings were designed. SD rats were used as animal models (n=10, 5 males and 5 females) to complete the magnetic anastomosis reconstruction of the cervical esophagus using magnamosis rings, and the operation time, animal survival, postoperative complications, magnetic rings excretion time were recorded. Two weeks after operation, the rats were killed, and the esophageal anastomotic specimens were obtained. The blasting pressure of the anastomotic site was measured and the formation of the anastomotic site was observed with naked eyes.ResultsEsophageal magnamosis was successfully performed in 10 SD rats, and the median operation time was 11 (8-13) min. All rats survived without anastomotic leakage, anastomotic stenosis, or magnetic rings incarceration. The magnetic rings were discharged after 8 (5-10) days and the burst pressure was higher than 300 mm Hg. Visual observation showed that the anastomotic muscle healed well and the mucosa was smooth.ConclusionThe magnetic compression technique can be used for anastomosis reconstruction of esophagus, which has the advantages of simple operation and reliable anastomosis effect, and has clinical application prospect.