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31.
Brunette I Rosolen SG Carrier M Abderrahman M Nada O Germain L Proulx S 《Veterinary ophthalmology》2011,14(6):365-377
Purpose The goal of this study was to report on the advantages and limitations of the pig and feline models for experimental in vivo corneal transplantation. Methods Ten healthy domestic pigs and ten healthy cats were used. Full thickness penetrating keratoplasty was performed using autologous (eight cases), allogeneic (seven cases) or human xenogeneic (three cases) tissue. In two other cases, the inflammatory response to partial thickness trephination (without transplantation) was evaluated. Eyes were assessed daily before and after surgery by slit‐lamp, pachymetry, and tonometry. A transparency score ranging from 0 (opaque graft) to 4 (clear graft) was used, based on the slit‐lamp examination. Optical coherence tomography, histology, and electron microscopy were performed postmortem. Results In the pig, the mean (±SD) transparency score for the eight full thickness grafts was 0.88 ± 0.99, ranging from 0 to 3. In the feline model, the mean transparency score for the seven uncomplicated grafts was 3.93 ± 0.19, ranging from 3.5 to 4. Both negative controls without endothelium remained opaque at all time. Intraoperative tendency for iris incarceration into the wound, rapid corneal swelling, suture cheese wiring, and postoperative intraocular inflammation were the main factors jeopardizing the functional success of the corneal transplant in the pig model. Conclusion Suboptimal functional results were obtained after full thickness corneal transplantation in the pig model, while in the feline model, the same protocol yielded uneventful surgeries and clear transplants, with functional results similar to those achieved in human subjects. 相似文献
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针对现有瓜科嫁接机砧木生长点去除不干净,以及生长点去除过程中砧木苗易损伤的缺点,该文以葫芦苗为试验对象,通过瓜科蔬菜砧木苗生长点去除理论运动轨迹分析和对生长点去除机构的动力学分析,设计开发了一种应用于瓜科蔬菜嫁接的生长点去除机构,该机构利用模仿人工方法通过手指去除生长点的原理,采用曲柄连杆机构外加柔性手指,实现生长点的去除。试验结果表明,砧木苗在13~17 d培育期间内,所设计的机构能较好地去除砧木苗生长点,去除成功率达90%以上,伤苗率小于5%,所研发的瓜科蔬菜嫁接砧木生长点去除机构是可行的。该研究可为解决蔬菜嫁接砧木苗生长点去除困难提供参考。 相似文献
34.
嫁接两年生茶树新梢主要生化成分的变化 总被引:1,自引:1,他引:1
研究了两年生嫁接茶树浙农113/鸠坑,龙井43/鸠坑,水仙/鸠坑及相应接穗,砧木品种新梢的主要生化成分,嫁接茶树浙农113/鸠坑,龙井/鸠坑氨基酸含量的升高,多酚含量的减少使其较对应接穗品种的酚氨比降低,而水仙/鸠坑的酚氨比升高,咖啡碱含量因嫁接组合的不同而呈不同的变化趋势,与嫁接一年生时的结果作比较,未表现出一致的规律,表明嫁接初时对茶树产生的影响有一个“时效”问题,嫁接后两年,嫁接茶树体的茶多酚,咖啡碱,氨基酸等主要滋味成分的含量受砧木影响较大。 相似文献
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OBJECTIVE: To evaluate the effectiveness of a herniorrhaphy technique, using an autogenous fascia lata graft (FLG) for perineal hernia (PH) repair in dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Twelve dogs with PH. METHOD: PHs were repaired with FLG harvested from the dog's ipsilateral thigh and sutured directly into the perineal defect. Correction of associated conditions, and castration were performed. Surgical time, pain, inflammation, pattern of defecation, lameness, hospitalization time, postoperative complications, and owner satisfaction were recorded. Histopathologic examination was performed in 1 dog euthanatized 10 months after repair. RESULTS: Hernia did not recur (mean follow-up, 5.8 months). Lameness was the most frequent minor complication, and was resolved within a few days. Transient rectal prolapse occurred in 2 dogs with bilateral PH. The mean (+/-SD) hospitalization was 1.8+/-0.9 days, and the surgical time was 76.5+/-9.8 minutes. Histopathologic examination in 1 dog revealed perfect integration of FLG into adjacent tissues without substantial tissue reaction. CONCLUSIONS: FLG reconstruction of PH is a simple, effective method of treatment. CLINICAL RELEVANCE: FLG can be used without major complications for primary repair of PH, as an augmentation procedure when the internal obturator muscle is thin or friable, or when herniation has recurred after another repair technique. 相似文献
37.
OBJECTIVE: (1) To determine whether an extracapsular patellar ligament/fascia lata graft would provide stability in the cranial cruciate ligament (CrCL)-deficient stifle comparable with that of the intact stifle. (2) To determine if different tibial anchor points would enhance stability of the CrCLdeficient stifle when compared with the standard fabellar-tibial suture (FTS) placement. STUDY DESIGN: Experimental. ANIMALS: Twenty-eight canine cadaver hind limbs. METHODS: Stifles were mounted in a jig and tested between loads of -65 and 80 N. After testing the intact CrCL, 4 stabilization techniques were tested after CrCL transection: lateral graft technique (LGT) and 3 FTS with different tibial anchor points. RESULTS: There were no significant differences in displacement between the LGT and standard FTS, between the LGT and the intact CrCL, or between the FTS and the intact CrCL, in either the Securos or the Screw-washer experiments. Stiffness of the intact CrCL was significantly greater than that of any stabilization technique and the cut CrCL. The standard FTS showed the least displacement of all suture stabilization techniques. Differences in stiffness were not significant between the suture stabilization techniques. CONCLUSIONS: Securely anchored, the LGT results in a reduction in drawer motion similar to that of the intact CrCL and the standard FTS. Altering the tibial anchor point for the FTS does not improve stiffness or enhance stabilization of the CrCL-deficient stifle. CLINICAL RELEVANCE: The LGT could be used for the treatment of CrCL ruptures in the dog. A clinical study is recommended. 相似文献
38.
Pooya HA Séguin B Mason DR Walsh PJ Taylor KT Kass PH Stover SM 《Veterinary surgery : VS》2004,33(4):301-308
OBJECTIVE: To compare the biomechanical properties of radial graft (RG) versus ulnar transposition graft (UTG) limb-sparing techniques in the dog. STUDY DESIGN: Cadaveric study. ANIMALS: Six pairs of normal canine thoracic limbs. METHODS: In each pair of limbs, 1 limb was subjected to the RG technique and the other to the UTG technique. Limbs were tested in axial loading until failure. Modes of failure and biomechanical properties were compared between the 2 groups. Percent coverage of the metacarpal bone by the plate was retrospectively compared between the limbs that failed by fracture of the metacarpal bones and those that did not. RESULTS: RG limbs had significantly greater stiffness, yield load, maximum load, maximum energy, and post-yield energy. All UTG limbs failed by cranial bending of the plate. Half of the RG limbs failed by caudal bending of the plate and half by fracture of the third metacarpal bone at the distal end of the plate. Limbs with <80% plate coverage of the metacarpal bone were significantly more likely to fail by metacarpal fracture. CONCLUSIONS: The RG technique was biomechanically superior to the UTG technique under the conditions studied. At least 80% plate coverage of the metacarpal bone should be achieved. CLINICAL RELEVANCE: Exercise restriction and coaptation bandages should be considered for patients undergoing the UTG technique to minimize potential biomechanical complications. 相似文献
39.
A greater one-horned Asian rhinoceros (Rhinoceros unicornis) presented for presumed ocular trauma to the left eye, with secondary bacterial infection, resulting in severe and progressive corneal ulceration. Following a poor response to medical therapy, the animal was anesthetized for further examination, and a bulbar conjunctival pedicle graft performed. This graft failed by 48-h postsurgery as a result of self-trauma. The animal was re-anesthetized, and a free island tarsoconjunctival graft performed. This second procedure was successful, resulting in globe preservation, cosmesis, and functional vision in the affected eye. 相似文献
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