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The current study was performed to understand the relationship between graft length placed within the bone tunnel and intraosseous graft healing in anterior cruciate ligament (ACL) reconstruction. Twenty-four adult beagle dogs were divided into two groups of 12 animals each. In each animal, ACL reconstruction using a 4-mm diameter autogenous flexor tendon graft was done in the left knee. In groups I and II, the graft having a length of 15 and 5 mm, respectively, was placed within the tibial tunnel. The proximal end of the graft was placed through the over-the-top route in all animals. In each group, five animals were sacrificed immediately after surgery, and the remaining seven were sacrificed at 6 weeks postoperatively. Biomechanical and histologic evaluations were performed. In pull out testing, the ultimate failure load and the linear stiffness of the graft-tibia complex harvested at 6 weeks were significantly greater than those harvested at the time-zero period. There were no significant differences in those parameters between groups I and II at 6 weeks. In each group, the perpendicular collagen fibers connecting the tendon to the bone tunnel wall were observed only in the narrow area located close to the intra-articular tunnel outlet. In conclusion, excessively long placement of the flexor graft within the bone tunnel does not result in an additional increase of anchoring strength and stiffness of the graft in ACL reconstruction.  相似文献   
3.
目的 为了减轻免疫诱导过程中对受体的侵袭 ,进一步探讨以家兔为动物模型 ,通过异体骨髓移植诱导同种皮肤移植免疫耐受。方法 通过骨髓腔内直接注射异体骨髓细胞 ,进行骨髓移植。结果 皮片的平均存活时间是 (88.0± 6 .0 )天 (P <0 .0 0 1 )。为了探讨其普遍性 ,我们用此诱导方法 ,还进行了同种全耳移植。平均存活时间是 (1 4 6 .0± 1 5 .1 )天 ,并有 1只移植耳存活时间已超过 1年 ,未见任何排斥反应。结论 本研究证明了以家兔为动物模型 ,在不使用免疫抑制剂的情况下 ,通过骨髓腔内直接注射异体骨髓细胞 ,进行骨髓移植的方法 ,不仅在皮肤移植上可以诱导长期稳定的特异性免疫耐受 ,而且在实质性器官耳的同种移植上取得了良好的效果  相似文献   
4.
We experienced a case of mediastinal lipoma, which is considered to be a relatively rare disease. A 3-year-old girl was referred to Gifu University hospital because of fever and an abnormal shadow on her chest X-ray. The chest X-ray clearly showed a well-delineated tumor shadow which seemed to oppress the diaphragm and the right atrium in the right lower lung area. A computed tomogram (CT) of the chest showed a homogeneous mass localized on the right diaphragm and adjoining the right anterior chest wall and heart. The mass showed a fat density measuring about-100 HU. Magnetic resonance imaging (MRI) showed a high-intensity mass which was almost the same level as the subcutaneous fat on both the T1-weighted and T2-weighted images. Thoracotomy was performed and a fatty tumor was found. It arose from the right side of the pericardium and adjoined the diaphragm, the anterior chest wall, and the thymus. There was no adhesion between the tumor and the surrounding organs. It was resected easily and its contents were yellowish and homogeneous. The patient made an uneventful recovery and was discharged 10 days after the operation. Light microscopy showed a lipoma consisting of mature adipose tissue and no malignancy was found.  相似文献   
5.
蝮蛇抗栓酶对骨内高压降压作用实验研究   总被引:12,自引:0,他引:12  
本实验随机将家兔一侧后肢于膝关节伸直位夹板外固定5周,制成固定侧胫骨上端骨内高压模型。对其全身和局部血液流变学指标进行测定,发现全血粘度,血浆粘度增大,血沉增快,血浆纤维蛋白原含量明显增高。对上述模型应用蝮蛇抗栓酶(svate)连续治疗21天,骨内压降低,血液流变学各项指标亦降低。本实验结果显示,蝮蛇抗栓酶通过改善骨内高压状态下的异常血液流变学状态可使骨内高压降低,从而认为血液流变学疗法可能成为临床治疗骨内高压症的一种新手段,而蝮蛇抗栓酶可能为其中高效药物之一。  相似文献   
6.
目的 探讨股动外膜交感神经网剥脱切除对骨内高压超微结构的影响。方法 30只新西兰纯种大白兔制作成右胫骨上端骨内高压模型,随机分为对照组和实验组,实验组行右股动脉外膜交感神经网剥脱切除术,测量手术前、后两组骨内压值及观察骨髓内超微结构。结果 手术后实验组骨内压值下降明显(P<0.05),骨髓内血窦腔及内皮细胞间隙大小无明显改变,内皮细胞结构、成分及血液成分趋向正常,血窦内血浆无形成分减少。结论 股动脉外膜交感神经网剥脱切除后,血液瘀滞状态有改善,骨内压下降。  相似文献   
7.
Sialolipoma is a new variant of salivary gland lipoma, which was first proposed by Nagao et al. (Histopathology 2001; 38: 30) in 2001. We report this rare case of sialolipoma in the hard palate. A 60-year-old Japanese woman was referred to our department complaining of a painless swelling on the right side of the hard palate. Intra-oral examination revealed a soft, elastic, dome-shaped mass with 1 cm in diameter located in the posterior part of the hard palate. Magnetic resonance imaging examination revealed high intensity on T(1)-weighted image and isointensity on T(2)-weighted image. Incisional biopsy revealed that the tumor was encapsulated by fibrous tissue, consisted of adipose tissue, and also contained normal salivary gland tissue peripherally. First diagnosed as an ordinary lipoma of the hard palate, the tumor was excised. According to the recent criteria of histologic findings of sialolipoma, we rediagnosed the tumor as sialolipoma of the hard palate.  相似文献   
8.
A 2-year-old boy presented with an accessory scrotum associated with penoscrotal transposition and a perineal lipoma. He also had a retrocerebellar arachnoid cyst. The accessory scrotum was resected with concurrent scrotoplasty. The retrocerebellar arachnoid cyst was seen on a subsequent brain computed tomography scan and was left untreated because there was no evidence that the volume was increasing.  相似文献   
9.
Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multi-nucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. the correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. in addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis.  相似文献   
10.
Hepatic angiomyolipoma (AML) is very rare and only about 80 cases have been reported. The tumor is fundamentally heterogeneously composed of the three tissue components of blood vessels, smooth muscle cells (SMC), and fat cells. Two cases of hepatic AML are reported here, both of which are histologically composed predominantly of a fat cell element and resembled true lipoma (lipomatous AML). However, careful examination of both tumors revealed the presence of a small amount of epithelioid SMC, especially around blood vessels. Immunohistochemical study using monoclonal antibody for melanoma (HMB-45) clearly revealed a small amount of HMB-45-positive SMC around the blood vessels and scattered in the diffuse fat cell growth in both tumors. Since no liver tissue components or primary liver tumors are reactive with HMB-45 except AML cells, the presence of HMB-45-positive cells within the tumor clearly established the diagnosis of hepatic AML. Any fatty tumor or focal fatty lesion of the liver that superficially resemble true lipomas should be tested for the presence of HMB-45-positive SMC in the tumor to differentiate it from AML.  相似文献   
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