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991.
Aspergillus infection can be a major cause of morbidity in immunocompromised patients, especially when there is pulmonary involvement. Diagnosis of aspergillosis is often complicated by the varied clinical presentation and compromised medical status of such patients. Four cases of head and neck Aspergillus infections in bone marrow transplant patients are presented. Involvement predominantly was limited to the oral cavity and/or sinuses, and in one case, the ear. Two cases were successfully managed with a combined antibiotic and surgical approach, and one case with antibiotics only. The fourth case was managed with antibiotics and surgery, but fatal hemorrhage secondary to sinus involvement developed.  相似文献   
992.
Cases of recurrence of breast cancer can pose considerable diagnostic and therapeutic challenges for the oncologic team. The prognosis and management decisions are based on knowledge of the true extent of disease. Conventional staging methods, including physical examination, assessment of levels of tumor markers, cross-sectional imaging, and bone scintigraphy, may not reliably demonstrate the extent of disease in all cases. Physical examination and cross-sectional imaging (computed tomography [CT] or magnetic resonance imaging) can be problematic because (a) the sequelae of previous surgery and radiation therapy can be difficult to distinguish from recurrent neoplasms and (b) early metastatic disease (small lesions) can be difficult to distinguish from benign lesions that are too small to characterize. Positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) can help clarify inconclusive findings from physical examination and cross-sectional imaging. FDG PET is more sensitive than CT in detection of lymphatic spread of disease to locoregional and mediastinal nodes. Metastases at distant sites including the lung, bone, and the liver are also readily detected at FDG PET. FDG PET has been proved accurate in restaging cases of recurrent breast cancer and will likely aid in directing therapy in these cases.  相似文献   
993.
994.
This is a report on A.F. Hecker, professor of medicine and founder of the scientific venereology in Germany in his historical period.  相似文献   
995.
Transendothelial cell diapedesis of neutrophils in inflamed human skin   总被引:1,自引:0,他引:1  
Summary The mode of extravasation of neutrophils (PMNs) in cutaneous inflammation was studied in sequential biopsy specimens taken from human skin. Inflammatory skin reactions were produced by intracutaneous injection of endogeneous mediators of inflammation — C5ades arg, LTB4, neutrophil-activating peptide (NAP) and interleukin-1 (IL-1). Within 30 min after injection neutrophils were observed in close contact with endothelial cells of postcapillary venules and, following cytoplasmic engulfment, the cells were found to be transported transcellulary through the endothelial layer. In a total of 20 biopsy specimens taken at various times, cell migration via interendothelial gaps was absent. Instead, the transcellular pathway appeared to be the first and foremost mode of diapedesis. During this migratory process PMNs lacked signs of degranulation and numerous electron-lucent vesicles and secondary lysosomes were found. In addition, coated pits present on leukocyte as well as endothelial-cell membranes were indicative of receptor-mediated endocytotic processes.  相似文献   
996.
Trauma und Berufskrankheit - Zusammenfassung Die Arthrodese am Fuß ist aus orthopädischer Sicht zur Funktionsverbesserung und Schmerzbeseitigung insbesondere bei chronischer Polyarthritis...  相似文献   
997.
The upward creep of the heart during myocardial single photon emission tomography (SPET) acquisition has been reported as a frequent source of false-positive results. The aim of this study was to simplify the detection and correction of this upward creep and to estimate its clinical relevance during routine patient care. To recognize the upward heart motion a straight line was fitted to the upper and lower border of consecutively displayed tomographic projection images. In this way, vertical translation of at least 1 pixel in size could be detected easily. On the assumption of a slow but continuous upward motion a fast interpolation correction method was developed. From 100 consecutive, supine, ergometric exercise studies, 1, 2 or 3 pixels of upward creep were found in 16, 4 or 3 patients, respectively. It was found that an upward creep of at least 2 pixels (7/100 cases) led to evident, mostly antero-septal defects on quantitative bull's-eyes, whereas only upward creeps of 3 pixels or more (3/100 cases) produced false-positive diagnostic results. The simple correction method offered a sufficient compensation of image and/or bull's-eye artefacts. These clinical findings could be reproduced in a computer model. Thus, it can be stated that clinically significant upward creep of the heart during stress SPET acquisition is relatively rare; it may have been overestimated in the past, and its artificial effects can be corrected by a quick and simple algorithm.Research fellow of the Alexander von Humboldt Foundation working at Department of Nuclear Medicine, University Medical School Szeged, Hungary  相似文献   
998.
Cytochrome P450 3A4 (CYP3A4) is a major determinant of the metabolism of many drugs, including important anticancer drugs, with sometimes profound impact on therapeutic efficacy and toxic side effects. To study in vivo CYP3A(4) functions, we have generated and characterized transgenic mice with functional expression of human CYP3A4 cDNA in the liver. Two transgenic lines displayed substantial, physiologically relevant and stable CYP3A4 levels in liver and moderate levels in kidney, but not in small intestine. The mice did not display obvious physiological abnormalities. The CYP3A4 substrate drugs midazolam and cyclosporin A were used to test functional activity of CYP3A4 in liver. The area under the plasma concentration versus time curve (AUC) of intravenously administered midazolam (30 mg/kg) was 2.2-fold decreased in the transgenic mice compared with wild-type (5.45 +/- 0.21 versus 11.7 +/- 0.46 microg . h ml(-1); P < 0.01), and early formation of the primary metabolite 1-hydroxymidazolam was about 2-fold increased, demonstrating the functionality of CYP3A4 in the liver. Similarly, following intravenous administration of cyclosporin A (20 mg/kg), CYP3A4 transgenic mice displayed a reduced plasma AUC compared with wild-type (24.3 +/- 0.66 versus 35.8 +/- 0.53 microg . h ml(-) (1); P < 0.01). Thus, midazolam and cyclosporin A, compounds with markedly different clearance rates and half-lives, both demonstrated clearly accelerated kinetics in the CYP3A4 transgenic mice. We expect that this CYP3A4 transgenic model will provide a useful tool to study the impact of CYP3A4 on drug levels, especially when combined with other transgenic and knockout strains.  相似文献   
999.
1000.

Background  

Studies have suggested that vitamin D may be important for both insulin sensitivity and insulin secretion, and that supplementation with vitamin D may subsequently prevent development of type 2 diabetes.  相似文献   
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