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BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease.  相似文献   
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Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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Monoclonal antibodies against cell surface receptors can be useful for the study of structural and biochemical features involved in protein interactions underlying platelet adhesion and aggregation. We report here the characterization of a monoclonal antibody, IID510g52 (hereafter referred to as IID5), which has been selected based on its specific binding properties against the platelet membrane glycoprotein IIIa. Characterization of the reactive epitope, including evolutionary conservation and identification of related IID5 target antigens in tumor cells, suggest that the IID5 epitope is implicated in the ligand-binding function of integrin receptors. Indeed, we show that this MoAb acts as a potent inhibitor of platelet aggregation and cell adhesion. Taken together, these results indicate that such a monoclonal may be a strategic tool for better understanding multiple integrin-mediated adhesive reactions, as well as the determination of interacting recognition sites.  相似文献   
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Summary Ten rabbits received by gastric tube 0.3 to 0.8 g pure cholesterol every second day for 4 to 8 weeks. Ten animals were used as control. Total serum cholesterol was determined weekly in experimental and control groups. The mean value of the total serum cholesterol in the experimental group was 482±79.6 mg/100 ml, about 2.5 times more than the cholesterol value of the control group (206±51.0 mg/100 ml).Early and selective lipid deposition was present in spontaneous mesenchymal thickenings of all aortas of the animals receiving cholesterol. The deposition failed to be observed in the aortic intima without that thickening. The intimal thickening is a change of the arterial wall that predisposes to lipid deposition.This observation supports the view that the proliferative changes seen in human atherosclerosis precede the lipid deposition and are a predisposing factor to this deposition.  相似文献   
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A microcomputer system for studying photo-plethysmography of the finger (PPF) was designed and applied to 50 non-premedicated healthy boys (one to ten years old) undergoing general anaesthesia (halothane in 70% N2O, with mechanical ventilation) for outpatient inguinal hernia repair. The purpose of this study was to assess the accuracy of computerized estimations of the photo-plethysmographic (arterial waves) amplitude and to evaluate whether or not PPF allows discrimination between two different surgical stimuli (skin incision, and manipulation of the spermatic cord). When anaesthesia was stable for at least five minutes (end-tidal halothane=1.25–1.5%;PetCO2=32–38 mmHg; SpO2≥98%; rectal temperature=36.3–37°C; ambient operating room temperature=20–21°C), and immediately before the skin incision, computerized estimations of the photo-plethysmographic (arterial waves) amplitudes (PPA) were recorded and saved for later comparison with direct (manual) measurements of the plethysmographic tracing, using an arbitrary scale of 0–255 units. Also, the values of PPA, systolic blood pressure, and pulse rate recorded immediately before the skin incision were later compared with the maximum changes in these same values recorded 30–90 sec after skin incision, and 30–90 sec after manipulation (traction + dissection) of the spermatic cord. Six boys (three to ten years old) stayed quiet enough, during induction of anaesthesia by mask, to allow regression analysis of PPA, systolic blood pressure, and pulse rate (Y) on end-tidal halothane/70% N2O (X). Computerized estimations tended to give a higher reading, by between 0.2 to 0.8 units, than direct measurements. Spearman and Kendall correlations showed that computerized and direct measurements were associated (P<0.0001), the Kolmogorov-Smirnov’s test revealed that the two distributions were identical (P=1), the mean difference between computerized and direct estimations of the PPA was 0.52±1.08 units, and the limits of agreement (?1.6 and 2.6 units) were small enough to be confident that computerized (automatic) estimations of PPA can be used for clinical purposes. Skin incision caused a smaller decrease of PPA (24%) than manipulation of the spermatic cord (37%). Changes in PPA were more pronounced than changes in systolic blood pressure or pulse rate (P<0.05). Linear regressions and Fisher’s exact test (two-tailed) showed that, during induction of anaesthesia with halothane in 70% N2O by mask (n=6), changes in end-tidal halothane concentration were related more to changes in PPA than to changes in systolic blood pressure and/or in pulse rate (P<0.05). In conclusion, computerized PPF allows discrimination between two different surgical stimuli, provides quantification of the sympathetic response to preoperative anxiety, and may be useful for studying pre-anaesthetic sedation.  相似文献   
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