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21.
Nonunion in the forearm following a radioulnar fracture is one of the nightmares of the orthopedic surgeon. Fortunately, it is rare. We treated a large bone defect of the forearm, using a vascularized fibular graft after excision of the unhealed bone segment in a 10-year-old boy with neurofibromatosis. This situation followed a double fracture that had been operated on several times using conventional methods. Following the debridement of the unhealthy tissues in the pseudoarthrotic region, the vascularized fibula was placed on the dorsal surface of the proximal radius fragment. The distal fragment of the radius was inserted into the fibular cavity and fixation was established with a Kirschner wire distally and with a plate proximally. Only two screws were used to fix the plate. The peroneal artery was anastomosed with the radial artery; one of its venae comitantes was anastomosed with the cephalic vein in an end-to-end fashion. After surgery, the elbow was immobilized at 90 degrees of flexion with a splint for 6 weeks. One year after surgery, forearm stabilization and elbow and hand functions were very satisfactory. However, because the distal epiphyses of the bones were destroyed following the repeated surgery and the original trauma itself, a very prominent difference between the two forearms occurred, suggesting the need for bone lengthening in the future. By presenting this case we would like to conclude that one can expect good bone healing with a vascularized bone transfer in these cases when there is not enough space to place screws, but support can be provided by an external splint and K wire.  相似文献   
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A morphological examination of synovial tissue from 25 patients with rheumatoid arthritis revealed that binucleated or multinucleated plasma cells were present in all samples and absent in synovia obtained from 16 control patients. Plasma cells containing two, three of four nuclei constitutet a mean 3% of the total plasma cell population. They were aways found amongst plasma cell infiltrates and in close association with small blood vessels. Ultrastructural analysis found no evidence of cellular membranes separating the individual nuclei in binucleated or multinucleated plasma cells, suggesting that the cells did not arise from fusion. Some of these plasma cells had a diameter approaching 100 μm, and many were in intimate contact with macrophages. The demonstration of a few cells with mitotic figures within the infiltrates suggests that the maintenance of plasma cell numbers in rheumatoid synovium may depend, in part, upon their local proliferation. Received: 25 August 1997 / Accepted: 2 October 1997  相似文献   
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OBJECTIVE: We aimed to demonstrate the time-dependent ultrastructural changes in pneumocyte type II cells following brain injury, and to propose an electron microscopic scoring model for the damage. METHODS: Forty Wistar-Albino female rats weighing 170-200 g were used. The rats were allocated into five groups. The first group was the control and the second was the craniotomy without trauma. The others were trauma groups. Weight-drop method was used for achieving head trauma. Samples were obtained from the right and left pulmonary lobes at 2-, 8-, and 24-h intervals after transcardiac perfusion. An electron microscopic scoring model was used to reveal the changes. RESULTS: There were no ultrastructural pathological findings pointing to lung injury in any rat of the control groups. There was intense intracellular oedema in type II pneumocyte and interstitial oedema in the adjacent tissue in trauma groups. Oedema in mitochondria and dilatation in both smooth endoplasmic reticulum and Golgi apparatus was more evident in the 8- and 24-h trauma groups. The chromatin dispersion was disintegrated in the nucleus in all trauma groups. Scores of all trauma groups were significantly different from the controls (P<0.05). All trauma groups were different from each other at significant levels (P<0.05 for each trauma groups). CONCLUSIONS: The data suggested that ultrastructural damage is obvious at 2 h and deteriorates with time. The electron microscopic scoring model worked well in depicting the traumatic changes, which were supported by lipid peroxidation. Further experiments are needed to determine the exact outcome after brain death model.  相似文献   
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Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h)201Tl (111 MBq) and 4-h and 24-h111In-octreotide (111–148 MBq) static planar anterior images (matrix 256×256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathologcial tumour size (mean largest diameter) was 3.38±1.9 cm.111In-octreotide detected 16 of the 17 breast cancers (94%) while201Tl detected 13 of them (76%). Both111In-octreotide and201Tl missed one nonpalpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5×1.5 cm. Of the four benign lesions, only the breast abscess revealed both201Tl and111In-octreotide uptake.111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed201Tl uptake. The tumour/background (T/B) ratios of late111In-octreotide and201Tl images were 1.71±0.38 and 1.46±0.30 respectively (P=0.039). In this preliminary study,111In-octreotide yielded more favourable results than201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of111In-octreotide imaging needs to be investigated in larger patient series.  相似文献   
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Oxygen-derived free radicals have been implicated in the pathogenesis of tissue injury after ischaemia-reperfusion. Caffeic acid phenethyl ester (CAPE), an active ingredient of honeybee propolis, has been identified as having potent antioxidant and anti-inflammatory properties. We evaluated the ability of CAPE applied intraperitoneally in reducing tissue injury after ischaemia-reperfusion. To investigate whether treatment with CAPE modifies the concentrations of the endogenous indices of oxidant stress, we examined its effects on a model of flap ischaemia-reperfusion injury in rats. CAPE (10 micromol/kg) was given through the peritoneum before reperfusion. CAPE given intraperitoneally had an inhibitory effect on tissue injury after ischaemia-reperfusion comparable to that of a control group. The anti-inflammatory and antioxidant properties of CAPE may contribute to its suppression of tissue injury.  相似文献   
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Bleeding into a pancreatic pseudocyst is a rare but life-threatening entity. Early diagnosis is crucial in its management. There are reports suggesting that computed tomography (CT), scintigraphy, endoscopic retrograde cholangiopancreatography (ERCP), and angiography could be the diagnostic maneuvers. In this report, we present a case of arterial bleeding into a pancreatic pseudocyst, which was diagnosed by the turbulent echo-currents seen in real-time ultrasonography.  相似文献   
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