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1.
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   
2.
In this report, a case is presented with large recurrent, benign, vascular and proliferative lesion on the scalp. Complete surgical excision of the tumor mass and split thickness skin grafting of the defect had favorable results with no recurrences after 24-month follow-up.  相似文献   
3.
During the treatment of patients with renal failure or renal transplants the most important consideration is to eliminate sources of infection before and after the treatment. Acute or chronic oral infections or bacteraemias resulting from dental procedures may cause serious complications in these patients who already have lowered host resistance caused by immunosuppressant therapy. In order to determine the latest concepts from some international transplantation centres relating to the importance of and the effect of infective sources in the oral cavity, a survey form was prepared which included several questions related to oral foci of infection and renal transplantations.
Results obtained from 22 centres from 12 countries indicated that the majority of the centres included a dental examination in their routine protocol and required completion of any necessary dental treatment before transplantation. However, full agreement among all these centres on the necessity for dental examination as part of the protocol has not yet been reached.  相似文献   
4.
Dysembryoplastic neuroepithelial tumor in the left lateral ventricle.   总被引:3,自引:0,他引:3  
Extracortical location of dysembryoplastic neuroepithelial tumor (DNT) is rare. We present a case of DNT localized in the left lateral ventricle of a 21-year-old female patient. Magnetic resonance imaging of the brain showed a round mass lesion in the floor of the anterior horn of the left lateral ventricle. The lesion was hypointense on T (1)-weighted images and slightly hyperintense on T (2)-weighted images without contrast enhancement. Total removal of the yellowish-white colored soft tumor was performed through a transcallosal approach. Histologically, the tumor was of simple type of DNT that was composed of small oligodendrogliocytes clustered tightly about perivascular spaces with neurons floating in mucoid pools showing an eosinophilic fibrillary matrix in the background. The recognition of DNT with an unusual location in lateral ventricle has therapeutic and prognostic significance since DNT is curable by surgical excision and radiation therapy is of no obvious benefit.  相似文献   
5.
Summary: The equilibrium swelling degree, modulus of elasticity and the spatial inhomogeneity of poly(N,N‐dimethylacrylamide) (PDMAAm) hydrogels were investigated over the entire range of the initial monomer concentration. The degree of dilution of the networks after their preparation was denoted by ν, the volume fraction of crosslinked polymer after the gel preparation. The linear swelling ratio of the gels increased linearly with increasing ν. Depending on the value of ν, three different gel regimes were observed: (1) For ν < 0.3, increasing ν decreases the extent of cyclization during crosslinking so that the effective crosslink density of gels increases with rising ν. (2) For 0.3 < ν < 0.7, increasing ν reduces the accessibility of the pendant vinyl groups during crosslinking due to steric hindrance at high polymer concentrations. As a result, the effective crosslink density of gels decreases with increasing ν. (3) For ν > 0.7, the modulus of elasticity increases sharply with increasing ν due to the increasing extent of chain entanglements in this high concentration regime. Static light scattering measurements on the gels show that the degree of spatial gel inhomogeneity in PDMAAm gels attains a maximum value at ν = 0.06. The appearance of a maximum as well as the ν‐dependence of scattered light intensities from gels was successfully reproduced by the theory proposed by Panyukov and Rabin.

Effective crosslink density νe of the hydrogels shown as a function of ν.  相似文献   

6.
Blood-borne metastases to the kidneys from solid tumors have received little attention in the medical literature because they usually occur in a setting of advanced systemic disease, and renal involvement is a elatively minor cause of symptoms. Although the frequency of metastases to the kidney in cancer patients is 7–13% in large autopsy series, incidental discovery of a renal metastasis as the first manifestation of a primary tumor is a very rare event. The most common primary malignancy to involve the kidney is bronchogenic carcinoma, followed by breast and gastrointestinal cancers. In this article, we report a patient with left colon cancer and isolated metastasis to the right kidney at the time of initial diagnosis. Left hemicolectomy and right nephrectomy were performed. Adjuvant systemic chemotherapy consisting of 5-fluorouracil (5-FU) and folinic acid (FA) was given. 5-FU and FA were stopped after four cycles because metastases to the lung and liver occurred about 3 mo after the surgery during adjuvant chemotherapy. Capecitabine was started. The patient died 9 mo after the discovery of the isolated renal metastasis. Nephrectomy is more for diagnostic clarification in the setting of synchronous primary because it has no effect on survival and its effect on quality of life is minimal; as seen in our case, the other organ metastases rapidly occur and the survival is limited. Nephrectomy may also compromise the choice of chemotherapy agents that require renal clearance, thus a careful evaluation of renal functions is necessary if a nephrectomy is performed. In the matter of a decreased renal clearance, the doses of these drugs should be decreased or the choice should be reevaluated.  相似文献   
7.
Primary nephrotic syndrome during childhood in Turkey   总被引:3,自引:0,他引:3  
BACKGROUND: Minimal change nephrotic syndrome (MCNS) is the most common cause of primary nephrotic syndrome (NS) during childhood. However, recent studies from different countries have reported an increasing incidence of focal segmental glomerulosclerosis (FSGS) in children. METHODS: This is a retrospective study in which 392 Turkish children who were diagnosed with NS during the last 10 years and were followed for at least 2 years, were evaluated. Mean age of the study group was 4.6 +/- 3.4 years (range 0.9-16 years) and 232 were male and 160 were female. RESULTS: In total, 280 patients were diagnosed as MCNS with their initial presentations, laboratory features, and clinical course. Kidney biopsy was performed in the remaining 112 children according to current recommendations. The results showed that membranoproliferative glomerulonephritis (MPGN) was the most common histopathologic diagnosis, 38 (34%) of the 112 patients were found to have MPGN. The number diagnosed as FSGS was 26 (23%). A significant difference was found between the age groups for both MPGN and FSGS, the former being more common in children >6 years of age and the latter more frequent in children 相似文献   
8.
9.
A selection of commercially available products containing stannous fluoride (SnF2)/sodium fluoride (NaF), SnF2/amorphous calcium phosphate (ACP), SnF2/NaF/ACP, tin (Sn)/fluorine (F)/chitosan were compared with phytosphingosine (PHS) with respect to their anti‐erosive properties in vitro. One‐hundred and twenty bovine enamel specimens were immersed in the respective product slurries for 2 min, twice daily. The formulations were diluted with either remineralization solution or artificial saliva. After each treatment, an erosive challenge was performed for 10 min, twice daily, using citric acid, pH 3.4. The specimens were stored in remineralization solution or artificial saliva until the next treatment‐erosion challenge. After 10 d, tissue loss was determined using profilometry. Enamel softening was determined through surface microhardness measurements. Tissue‐loss values (measured in μm and expressed as mean ± SD) for PHS, SnF2/NaF, SnF2/ACP, SnF2/ACP/NaF, and Sn/F/chitosan treatment groups and for the negative‐control group, were, respectively, 35.6 ± 2.8, 15.8 ± 1.8, 22.1 ± 2.0, 22.9 ± 1.8, 16.2 ± 1.2, and 51.2 ± 4.4 in the presence of remineralization solution and 31.7 ± 3.3, 15.6 ± 2.9, 16.5 ± 2.7, 16.8 ± 2.1, 13.1 ± 3.0, and 50.7 ± 2.8 in the presence of artificial saliva. There were no significant differences in surface microhardness measurements between the treatment groups. In conclusion, PHS resulted in a significant reduction of tissue loss compared with the negative control, but in comparison, the toothpastes containing Sn2+ and F? ions were significantly more effective compared with PHS.  相似文献   
10.
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