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1.
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   
2.
Cranial malignant fibrous histiocytomas are rare tumors. Most are hypervascular, destructive masses that are similar to other malignant lesions and to malignant fibrous histiocytomas found elsewhere in the body. We describe a myxoid malignant fibrous histiocytoma of the temporal bone, possibly of dural origin, with features that more closely resembled a meningioma at CT, MR imaging, and angiography.  相似文献   
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4.
Brainstem auditory evoked potentials (BAEPs) were recorded from 39 preterm infants, divided into 3 groups: small-for-gestational-age, with a birthweight less than or equal to 1500 g (SGA); appropriate-for-gestational-age, with a birthweight less than or equal to 1500 g (AGA1); and appropriate-for-gestational-age, with a birthweight higher than 1500 g (AGA2). A significant shortening of the I-V interval due to an increase in wave I latency was found in the SGA group. The lower-weight AGA group (AGA1) was never significantly different from the SGA group. Although there was no correlation between conceptional age and weight at the time of the examination for the studied population, negative correlations were found between wave I latency and weight at the time of the examination. These findings confirm previous research and suggest the existence of a link between weight and basal cochlear maturation.  相似文献   
5.
Cultures ofTrypanosoma (Megatrypanum) freitasi with L929 mouse fibroblasts at 27.5°C were examined by scanning and transmission electron microscopy in an attempt to clarify the processes of colony formation by the epimastigotes and of their attachment to substrata. It was seen that the flagellates occupy intercellular spaces and do not associate with intact fibroblasts. As the trypanosome population increases, ever larger portions of the substratum are cleared of fibroblasts and occupied by conglomerates of epimastigote colonies consisting of about a dozen organisms that attach to the substratum by their anterior extremities and form pyramidal clusters. Attachment of the epimastigotes involves the flagellar membrane, which becomes extraordinarily enlarged and assumes various aspects of broad sheets, filaments and loops over the substratum or along the flagellum, which exhibits a shortened axoneme. Desmosome or hemidesmosome plaques are present when the attachment takes place between membranes or between the membrane and the substratum.Supported by grants from CNPq and FINEP  相似文献   
6.
Sleep disorders in women: clinical evidence and treatment strategies.   总被引:4,自引:0,他引:4  
Sleep disorders are more prevalent in women than in men. Sex hormones modulate sleep-wake behaviors and mood and may contribute to heightened risk across the life cycle of women. Sleep disorders may have a unique expression in women, emerging throughout their reproductive life cycle. These conditions require careful treatment strategy to manage medical, hormonal, and behavioral contributing factors to poor sleep efficiency and impaired quality of life. This review focuses on clinical evidence for sleep disorders in women and discusses existing evidence of risk factors and treatment options for insomnia and sleep-disordered breathing in women.  相似文献   
7.
In this oral presentation, the author emphasized the need for individualization of drug treatment, reviewing the most known factors of variability in drug response. The importance of studies of clinical pharmacokinetics was focused. The main parameters for a judgement on the efficacy and virtual tolerability of a medicine, on the basis of its sequential concentrations in the blood after administration, were briefly outlined. The influence of congestive heart failure on the volume of distribution, systemic clearance, elimination half-life and bioavailability, was discussed. The changes that renal failure makes in drug elimination were equally presented, having been pointed the modification of protein binding, volume of distribution, and hepatic elimination. A selection of eight clinical cases was summarily presented, to illustrate the important contribute that can be afforded to practice by pharmacokinetics. The dosing of aminoglycosides and of other drugs with narrow therapeutic ranges was evaluated through some of the examples. A case of complex interferences of heart failure, renal failure and therapeutic hemoperfusion on the kinetics of an antibiotic drug was included. Two cases of intoxications (phenytoin and theophylline), whose management has been greatly improved by repeated drug dosing in blood, were discussed, too. A special call of attention was made to the need the currently practicing physician has of being aware of kinetic characteristics of the drugs he prescribes, and of how can disease modify the body fate of those medicines, and their therapeutic and nontherapeutic effects.  相似文献   
8.
This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine.  相似文献   
9.
The involvement of the pulmonary vessels by tumour emboli may lead to a clinical picture defined as 'subacute cor pulmonale'. Information about this syndrome has been limited to case reports and a few series. A study of 214 autopsied cancer patients was undertaken to investigate the clinical signs and symptoms of tumour involvement of the pulmonary vessels (TIPV). The lungs were removed as a block and 15 sections (3 from each lobe) were analyzed. Clinical data about right ventricular failure, dyspnoea, cough, pleuritic chest pain, cyanosis, engorgement of jugular veins, peripheral oedema, haemoptysis and haemoptoic sputum were obtained from the medical records of each patient. Tumour emboli were detected in 89 cases, and no respiratory symptoms were recorded in 39. The presence of dyspnoea and cyanosis were highly significant in the group with TIVP, and right ventricular failure and peripheral oedema showed slight significant differences between the patients with and without TIPV. The classical picture of subacute cor pulmonale was observed in 13 patients and TIPV was considered to be the main cause of death in 29 cases. Our results indicate that although the development of subacute cor pulmonale was rare in patients with cancer, TIPV may be suspected when the patient presents respiratory distress and should be included in the differential diagnosis of dyspnoea in cancer patients.  相似文献   
10.
Increased amounts of brown adipose tissue have been reported to occur in association with several diseases. The objective of the present study was to determine whether brown adipose tissue accumulation is related to nutritional status. Histologic sections of periadrenal tissue prospectively obtained at consecutive autopsies from 366 adults were examined. The cases were separated into three groups: malnourished (101 autopsies), normotrophic (128 autopsies), and obese (137 autopsies), according to the Quetelet index. Of these patients, 89 had brown adipose tissue accumulation, 35 were malnourished, 32 were normotrophic, and 22 were obese. The results showed a correlation between brown adipose tissue and patient nutritional status and a higher brown adipose tissue accumulation in malnourished patients. Cardiovascular disease was the most common type of illness present in the cases with brown adipose tissue accumulation.  相似文献   
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