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Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification.  相似文献   
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Myocardial activation under depolarized conditions was studied in spontaneously beating Langendorff perfused hearts from albino rats. Depolarization was obtained by increasing external potassium concentration in steps (5.4, 7.4, 10, 10.5, 11 and 11.5 mM) in the perfusing solution with or without adrenaline (Adr). Left ventricle isovolumic systolic pressure and coronary flow did not change as external potassium increased, albeit being larger with Adr in the perfusing solution. Atrial and ventricular rates decreased, the latter showing a larger decline. The same behaviour was displayed by perfused hearts, with higher rates being developed by the group with Adr. PR interval and QRS complex duration increased as a function of external potassium. PR intervals were the same in both groups but QRS duration was larger in the Adr group, indicating that AV conduction was not changed in presence of Adr but intraventricular conduction was delayed in that situation. It was also observed that in the great majority of perfused hearts, differing from isolated preparations, ventricular mechanical activity ceased at around 11.5 mM external potassium.  相似文献   
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The authors present a case of infected emphysematous bulla. Surgical treatment is always indicated also when a preoperative sure diagnosis between this and other pulmonary infections is not possible. The surgical management is often simple, without serious postoperative complications.  相似文献   
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The follicular basement membrane (FBM) prevents thyroglobulin from escaping to the peri-follicular space, where it can act as an antigen to induce experimental thyroiditis. Laminin, a component of the FBM, is responsible for directing cell migration and stimulates greater adhesion of activated T lymphocytes. Our purpose was to study the expression of laminin in the thyroid of NOD mice, which have a propensity for autoimmune diseases, including thyroiditis. Thirty NOD mice between 3 and 42 weeks old were studied. Eight had thyroiditis and 22 showed no inflammatory infiltration. An immunohistochemical examination using the streptavidin-biotin-peroxidase technique was conducted on paraffin-embedded tissue sections, with a polyclonal antilaminin antibody. Antigen retrieval was achieved through pepsin digestion and microwave irradiation in citrate buffer. Staining for laminin was restricted to the basement membrane. In thyroids with no infiltration, laminin was shown as a fine, continuous brown line in the basement membrane. In 6 out of the 8 cases of thyroiditis, clearcut interruption and destruction of the FBM was observed, particularly when the follicles were located in lymphocyte infiltrated areas or when there was fibrosis. There were significant alterations in the pattern of the FBM with extensive areas of discontinuity in the distribution of laminin. Such discontinuities could facilitate antigen exposure, especially thyroglobulin, which may contribute to autoimmune thyroiditis in NOD mice.  相似文献   
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