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Neurofibromas are benign neoplasms of the peripheral nerve sheath, characterized by the proliferation of Schwann cells, perineural cells and endoneural fibroblasts. Their occurrence in the oral and maxillofacial complex is uncommon. This study aimed to evaluate the clinical and histopathological characteristics of neurofibromas of the oral and maxillofacial complex excised at our institution over a 48-year period. Using light microscopy, two previously trained oral pathologists re-evaluated all hematoxylin and eosin slides. From a total of 15,375 cases diagnosed at a referred Oral Pathology Service, 24 cases were diagnosed as neurofibromas. Eighteen neurofibroma patients were female, with a mean age of 39.1 years. Three patients presenting neurofibromas exhibited neurofibromatosis type I. Clinically, most of the lesions presented as asymptomatic nodules, and the most frequent sites were the tongue (n = 6; 25.0%), gingiva (n = 6; 25.0%) and intraosseous maxillary bone region (n = 3; 12.5%). Histopathologically, the lesions were predominantly well delimited, exhibiting interlocking bundles of spindle-shaped cells that usually displayed wavy nuclei, associated with delicate collagen fibers. Thus, knowledge of their clinical and histopathological features by dentists and oral pathologists is essential for the correct diagnosis of these lesions.  相似文献   
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A 6-year-old girl with Glanzmann thrombasthenia presented with caries and periapical lesions in the primary mandibular second molars and moderate gingivitis of the maxillary and mandibular anterior teeth. Dental extraction was recommended, and before every surgical intervention, the patient underwent platelet-concentrate transfusion to prevent hemorrhage. Epsilon aminocaproic acid was administered 6 hours before, and 48 hours after every dental procedure to prevent bleeding. In this case, treatment was effective in the prevention of hemorrhagic complications, during the required dental procedures.  相似文献   
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Britto RR, Rezende NR, Marinho KC, Torres JL, Parreira VF, Teixeira-Salmela LF. Inspiratory muscular training in chronic stroke survivors: a randomized controlled trial.

Objective

To assess the effectiveness of inspiratory muscular training (IMT) on measures of strength, resistance, functional performance, and quality of life (QOL) for chronic stroke survivors.

Design

Double-blinded randomized controlled trial.

Setting

Research laboratory.

Participants

Subjects (N=21) with stroke (11 men, 10 women; maximal inspiratory pressure [MIP] <90% of predicted values) were randomly assigned to the experimental (n=11) and control groups (n=10); 18 participants completed all testing and training.

Interventions

Interventions were based on home-based training, with resistance adjusted biweekly to 30% of MIP for the experimental group. The control group underwent the same protocol without the threshold resistance valve. Both groups received home training 30 minutes a day 5 times a week for 8 weeks.

Main Outcome Measures

MIP, inspiratory muscular endurance (IME), functional performance, and QOL.

Results

There were significant between-group differences for the MIP and IME measures. Significant changes were observed for only the experimental group for MIP (67.8±14.6 at baseline to 102.2±26.0cmH2O at posttraining) and IME (31.8±19.3 to 49.2±21.1cmH2O). No statistically significant differences were observed for measures of functional performance and QOL.

Conclusions

Significant short-term effects of the IMT program for inspiratory strength and endurance were observed in chronic stroke survivors. These findings gave some indications that IMT may benefit people with stroke, and it is feasible to be included in rehabilitation interventions with this population.  相似文献   
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To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge.  相似文献   
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BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates.  相似文献   
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IntroductionCholangiocarcinoma is a rare tumor but recent data report a worldwide increase in incidence and mortality. There are several risk factors associated with cholangiocarcinoma, and chronic inflammation of billiary tree seems to be implied in the cholangiocarcinogenesis, but little is known about this process.Presentation of caseWe present a 56-year-old female with a bile duct adenoma incidentally discovered in the follow up of breast cancer that 18 months later progress to intrahepatic cholangiocarcinoma.DiscussionThis is a rare presentation of intrahepatic cholangiocarcinoma that suggests the classic adenoma-carcinoma sequence in cholangiocarcinogenesis. Furthermore this case gives rise to some questions about the possible common ground on intrahepatic cholangiocarcinoma and breast cancer.ConclusionCholangiocarcinogenesis is a complex multi-step mechanism and further investigations are needed to fully understand this process.  相似文献   
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