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91.
Genomic signature maps of different cell types can aid in the interpretation of genomic data of specimens collected during disease states. We have defined "lineage-specific" genes, as well as "activation" genes, for cellular components of the skin: keratinocytes, fibroblasts, macrophages, monocytes, T cells, immature, and mature dendritic cells (DCs). Re-analysis of a previously published gene set of psoriasis then provided a model for assessing the usefulness of these maps. We were able to ascribe over 90% of these genes to specific cell types, and there was a surprisingly large contribution from DCs. This shows the utility of such cellular gene maps.  相似文献   
92.
The authors report a case of hemarthrosis complicated by severe anemia related to a congenital connective tissue disease: Ehlers-Danlos syndrome. A boy fell down and suffered tumefaction of both knees with bilateral rupture of the rotula tendon. He underwent surgical reinsertion of each tendon on the rotula. He later showed an unexpected ongoing hematic effusion, with severe anemia. He was screened for coagulation disorders with no results. On taking a more detailed history and investigating the patient's phenotypical features, the authors diagnosed Ehlers-Danlos syndrome, hypermobile variant. The hemarthrosis and anemia were thus concluded to be consequences of excessive tissue fragility due to a congenital connective tissue disease.  相似文献   
93.
Hydrostatic pulmonary edema is as an abnormal increase in extravascular water secondary to elevated pressure in the pulmonary circulation, due to congestive heart failure or intravascular volume overload. Diagnosis of hydrostatic pulmonary edema is usually based on clinical signs associated to conventional radiography findings. Interpretation of radiologic signs of cardiogenic pulmonary edema are often questionable and subject. For a bedside prompt evaluation, lung ultrasound (LUS) may assess pulmonary congestion through the evaluation of vertical reverberation artifacts, known as B-lines. These artifacts are related to multiple minimal acoustic interfaces between small water-rich structures and alveolar air, as it happens in case of thickened interlobular septa due to increase of extravascular lung water. The number, diffusion and intensity of B lines correlates with both the radiologic and invasive estimate of extravascular lung water. The integration of conventional chest radiograph with LUS can be very helpful to obtain the correct diagnosis. Computed tomography (CT) is of limited use in the work up of cardiogenic pulmonary edema, due to its high cost, little use in the emergencies and radiation exposure. However, a deep knowledge of CT signs of pulmonary edema is crucial when other similar pulmonary conditions may occasionally be in the differential diagnosis.  相似文献   
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To assess the feasibility of contrast-enhanced ultrasound (CEUS) of the thyroid gland and to evaluate the potential of this method for characterising solitary thyroid nodules.18 patients affected by solitary thyroid nodules (size range: 0.6 to 3.6 cm; mean: 1.8 cm) confirmed by surgery (nine papillary carcinomas, four follicular carcinomas, three hyperplasias, one follicular adenoma and one Plummer’s adenoma) underwent pulse inversion US at low M.I. (0.06 to 0.08) after i.v. injection of a 2.4-mL bolus of SonoVue. Baseline echogenicity and the dynamic enhancement pattern of each nodule, in comparison with adjacent thyroid parenchyma, were assessed. Signal intensity values on grey-scale images were also calculated at baseline, 30 s, 60 s and 120 s after SonoVue administration. Following administration of SonoVue, malignant nodules showed absent (4 out of 13), faint dotted (4 out of 13) and diffuse (5 out of 13) contrast enhancement, in this last case inhomogeneous (4 out of 5 cases) or homogeneous (1 out of 5). Benign nodules showed diffuse contrast enhancement, both homogeneous (3 out of 5) and heterogeneous (2 out of 5). Quantitative data have confirmed subjective findings, but CEUS never modified precontrast analysis. CEUS of thyroid gland is a feasible technique, but overlapping findings seem to limit the potential of this technique in the characterization of thyroid nodules.  相似文献   
98.
PURPOSE: The aim of this study was to investigate the effects of magnetic fields (MF) of different intensity generated by a magnetic resonance (MR) unit (0.5 Tesla) and a double cylindrical coil (0.5 m Tesla) on human CD4(+) T cell lines. MATERIALS AND METHODS: CD4(+) T cells were exposed for two hours under isothermal conditions (37 +/- 0.5 degrees C) to the above mentioned MF; a control group was provided for each exposed sample. After exposure, the samples were analysed in the laboratory for the following endpoints: release of cytokines, expression of surface markers, cell proliferation and levels of cytosolic free-calcium. RESULTS: Exposure to MF for 2 h and subsequent in vitro stimulation in the presence of the appropriate mitogen, caused a decrease of interferon-gamma production, a decrease of cell proliferation, a decrease of expression of CD25 and a decrease of cytosolic free calcium concentration in exposed CD4(+) T cell lines. Data obtained, were statistically significant when evaluated after 24 h of in vitro culture, but were not significant, for both types of MF, when the experimental groups were analysed after prolonged in vitro culture. CONCLUSION: These results indicate that static magnetic fields (SMF) can give rise to transient biological effects on T lymphocytes and the present system is a sensitive model for understanding the effects of MF on the immune system.  相似文献   
99.
The mediastinum is divided into compartments (anterior, middle, posterior) on the basis of lateral chest radiographs. Several anatomical and radiological classifications of the mediastinum are reported in the literature. Most mediastinal abnormalities are initially suspected following chest radiography; the need for further investigation and the most appropriate imaging modality are largely dictated by the tentative diagnosis made on this examination. Although routine chest radiography initiates the evaluation of mediastinal disorders, it is rarely diagnostic: notable exceptions are teeth or bones within a mass, which are diagnostic of a teratoma; air/fluid levels suggest an oesophageal origin, hernia, cyst, or abscess. Chest radiography is followed by spiral computed tomography (sCT). However, even sCT with contrast material is occasionally diagnostic (a confident diagnosis can be made of some lesions such as mature teratoma and mediastinal goiter) but is usually sufficient for preoperative evaluation before mediastinotomy or mediastinoscopy: it is instrumental in planning further diagnostic workup. In certain cases, magnetic resonance imaging (MRI) may be complementary to sCT, but its use is not considered routine. Besides, although the anterior mediastinum is suitable for sonographic examination, the diagnostic value of ultrasonography has not been fully exploited. Thyroid scanning with radioactive iodine is useful in identifying and evaluating masses of suspected thyroid origin. The role of fluorodeoxyglucose positron emission tomography (FDG-PET) in mediastinal diseases continues to be evaluated: it has potential for differentiating between benign and malignant disease and is expected to play a more extensive role in the imaging of mediastinal neoplasms in the future. In this paper, the radiological features of masses located in the anterior mediastinum are discussed, with particular reference to radiographic and CT patterns useful to the clinician's everyday practice.  相似文献   
100.
This study describes the diffuse neoplastic conditions that may affect pleural membranes. These include mesothelioma, the most important and common malignancy of pleural origin, and metastatic involvement by carcinomas, lymphomas and thymomas. On the basis of diagnostic imaging, we identify the distinctive features of pleural involvement by each of these conditions and provide elements enabling accurate differential diagnosis. Finally, we discuss the best diagnostic approach in the case of suspected primary or secondary neoplastic involvement of pleural membranes.  相似文献   
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