Objective To compare the effect of calcium sulfate pellets made by different methods in repair of segmental radial defect of rabbits. Methods Eighty white New Zealand rabbits were sub-jected to defects of middle part of the left radial bone and divided into four groups according to repair ma-terials: control group (Group A, implanted with no artificial bone substitute), uncoated pressed calcium sulfate pellets (Group B), coated pressed calcium sulfate pellets (Group C) and coated pressed calcium sulfate pellets combined with rhBMP-2 (Group D). Histologic examination and biological test were done at 4, 8 and 12 weeks after operation. The data were processed with mono-factor variance analysis. Re-sults New bone formation was found on the defected bone in Group D and Group C, with better in Group D. The bone strength test showed that the anti-bending strength was (39.6±1.7) % in Group C and (47.5±2.1) % in Group D, which were higher than (21.3±2.7) % in Group A and (23.6±3.3) % in Group B, with higher anti-bending strength in Group D than that in Group C (F = 125.3 ,P <0.01). Conclusions For restoration of segmental bone defects, chitosan-coated pressed calcium sulfate pellet shows relatively high density and slightly slow resorption, which closely coincides with the growth rate of new bone. The coated pellet combined with rhBMP-2 can enhance its osteogeneais in restoring segmental Done defects.

[Objective]To explore the effects on surrounding tissue and bone regeneration by citrated calcium sulphate(CCaS) and Ostesset~.[Method]Bilateral or lateral femoral condyles were drilled into defects in 18 rabbits,and divided into 3 groups: A,12 rabbits,left defect filled with CCaS cylinder,right defect with osteoset~;B,3 rabbits,left defect with CCaS,right defect blank;C,3 rabbits,left defect with osteoset~GFDA3,right defect blank.The rabbits were sacrificed at 3 wks,6 wks and 13 wks,and defect samples were taken for histological exam,roengenographic observation and bone tissue calculation by image-plus CCD system.[Result]The defects that were not grafted were filled with bone marrow and there was minimal new bone,only at the margen of the defects CCaS and osteoset~GFDA3 implanted in the defects were gradually absorbed,and substituted by new bone trabecula,which became more mature and thicker.The area fraction and trabecula thickness of new bone in defects treated with CCaS were not significantly different from defects treated with osteoset~ after 3,6,13 wks.However,the degradation velocity of CCaS was slower than that of osteoset~.No inflammatory and foreign body response was observed.[Conclusion]Just like osteoset~,CCaS is more benefitial to new bone formation compared with osteoset~,because CCaS has relatively slower degradation velocity.

0.05).The maximum relaxant forces of vitrification and fresh arteries groups were greater than the freezing group(P 0.05).The arteries of three groups began obvious relaxant responses when sodium nitroprusside was 10-7 mol/L, and nearly reached their maximal relaxant responses when sodium nitroprusside was 10-4 mol/L.CONCLUSION:The vitrification could preserve more active smooth muscle cells of arteries than the freezing method.The norepinephrine has better effect on contraction ability of artery, which preserved in the vitrification group than the freezing group;however, there is no difference in relaxation of sodium nitroferricyanide.

Objective To research and make one kind of intravascular soluble hollow stent for vascular anastomosis. Methods According to the chemical industry, CaCl2, polyethylene glycol (PEG)and gelatin were used to make one kind of intravascular soluble hollow stent for vascular anastomosis, whose surface was covered with CaCl2 membrane(CaCl2 hollow stent). After putting the stent into the two cut sides of vascular, the author put the two sides together, and dropped alginic acid sodium solution, CaCl2 solution, and glue respectively. As soon as the glue solidified, the anastomosis was finished. Results The CaCl2 hollow stent could not only support the cannel of vascular, but also generate two membrane in the two side of anastomosis site. Thus the thickness of sealant was increased. It was effective to prevent leaking of cyanoacrylate glue and its toxicity. Conclusion The CaCl2 hollow stent can generate two membrane in the two side of anastomosis site, and could increase seal effectively. Using this stent could improve the anastomosis patency by increasing the sealant thickness, and preventing leakage of cyanoacrylate glue and its toxicity.

Periosteal autograft from different sources have been used to repair 1.5cm bone defects of radius in 10 rabbits.On the left side,sharp-dissected grafts were implanted and the animals were sacrificed 4,8,14,30 and 60 days after operation.Bone formation was studied with X-ray and histologic technique.The results showed that the way of sharp-dissecting can preserve the periosteum completely,and good bone formation was found in this group.It suggested that the sharp-dissecting of the periosteum is the important key for periosteal graft.

[Objeetive]To report the repairing offect of cancellous bone defect with calcium sulphate.[Method]A defect 5mm in diameter and 12 mm in deep,which was drilled in the lateral aspect of rabbit lateral femoral condyle,was filled with CCaS(Citrated Calcium Sulphate)cylinder or Osteoset tablets respectively.Rabbits were killed 3,6,13 weeks after surgery.And then general oberservations and mechanical analyzing were conducted.[Result]After surgery,rabbits had good movements,spirits and eating,good healing of incision.There was no arthroedema and inflammatory response around the joints.Mechanical analyzing reports:both anticompressive strength and elasticity coefficient in the artificial bone repair bone defect area 3 weeks after surgery,were higher than in that of normal femur condyle;Anti-compressive strength and elasticity coefficient in the defect area 6 weeks,which drop comparing to 3 weeks,was lower than that of normal femur condyle;Anti-compressive strength and elasticity coefficient 13 weeks,which is higher than 6 weeks,is approaching normal.Mechanics intensity of two groups in the different time had no significant difference,but was significantly higher than one of the same time blank group.[Conclusion]To some extent,Calcium Sulphate has mechanical supportive effects on cancelloues bone defect in spite of the absorption and degradation of Calcium Sulphate.There is no significant difference between Citrated Calcium Sulphate and Osteoset tablets.

In order to determine the efficacy of mannitol and anisodamine in the treatment of compartment syndrome, a new animal model of compartment syndrome was used to observe the changes in CPK, MDA, tissue pressure and pathology before and after the use of the drugs. The results showed that the values of CPK, MDA and intracompartmental pressure declined and pathological changes improved after the therapy. The result indicated that this new animal model is reproducible and successful. Mannitol is useful in the treatment of compartment syndrome, and at the same time it acts as a free radical scavenger, so that it can prevent reperfusion injury. Anisodamine can improve the limb's microcirculation. CPK can be an index for judging the therapeatic effect in the treatnent of compartment syndrome.

Bi-polar,bi-pedicled separation delayed flaps were designed on the backs of New Zealand rabbits with the application of a medical silicon membrane as the separation material. Values of glucose and lactic acid, PtcO 2 were measured separately at proximal,middle and distal areas of the flaps after the distal pedice was cut at 0,1,4,7,14,21 days,respectively, after the formation of flaps. After flap delaying,PtcO 2 in separated flap was always lower than that of the mormal control,accompanied with glucose decrease and lactic acid increase, although there were significant differences in different areas of the flap. The survived area of the flap increased after 7 days. Furthermore,all the length of the flap survived after 21 days,although the level of glucose in the flap was still lower and lactic acid was still higher.The results suggested that by separation and delaying the flap may adapt gradually to hypoxia via lowered metabolism.For flap survival,the threshold value of glucose in flap is 0 01mmol/L , lactic acid is 0 47mmol/L,and PtcO 2 is 3mmHg .

Relation between change of capillary pressure, survival length in bi pedicled separation delay flap was observed. Bi polar, bi pedicled separation delay flaps were designed on the backs of New Zealand rabbits. Medical silicon membrane was used as separative material. Values of capillary pressure were measured at proximal, middle and distal points. Survival length increased with delayed time, capillary pressure at middle was lower in the bi pedicled separation delay flap. It is concluded that capillary pressure is increased greatly by separation delay, and there is a linear relation between capillary pressure and survival length of flaps.

Objective To evaluate the causes,clinical manifestations and diagnosis of tarsal tunnel syndrome. Methods Operation was performed for 18 patients ( 21 sides) with tarsal tunnel syndrome. Preoperative Takakura index was 3-7 points with an average of 6.4 points. Ganglion was found in 15 cases (17 sides), varicosity in 2 cases (3 sides) and lipoma in 1 case. Results The symptoms disappeared without recurrence in 0.5 to 17 years' follow-up (average 7.3). Postoperative Takakura index was 9-10 points (average 9.7). Conclusion Tarsal tunnel syndrome is rare in the clinical practice with varied causes and different clinical manifestations. Operation can be performed with satisfactory results for the patients unsuitable for conservative treatment.