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31.
Evaluation of the competence of a mitral valve can often be impossible in the clinical setting of a giant atrial myxoma. A 50-year-old woman with severe mitral regurgitation in the post-bypass period following a myxoma resection was managed with a mitral valve replacement.The absence of mitral insufficiency in the preoperative examination should not be taken as a reliable predictor of normal valve function. So herein, we discuss the role of the intraoperative echocardiographic examination, the underlying mechanisms, and the proposed management of severe mitral regurgitation following the resection of an atrial myxoma.  相似文献   
32.
Superficial granulomatous pyoderma gangrenosum, a rare variant of pyoderma gangrenosum, has been considered to be the most benign form of the disease. We present the case of a 15‐year‐old boy with pulmonary involvement and nodular scleritis associated with this unusual type of pyoderma gangrenosum and discuss its differential diagnosis.  相似文献   
33.
Las circunstancias actuales provocadas por la COVID-19 nos obligan a los profesionales de atención primaria a idear nuevas formas de garantizar la atención sanitaria de nuestros pacientes con diabetes tipo 2 (DM2). Existen evidencias que respaldan la eficacia de la telemedicina en el control glucémico de los pacientes con DM2. Ante la rápida adaptación de la práctica clínica al uso de la telemedicina, el Grupo de Trabajo de Diabetes de la Sociedad Española de Medicina Familiar y Comunitaria (SemFyC) optó por elaborar un documento de consenso plasmado en un algoritmo de actuación/seguimiento telemático en la atención de los pacientes con DM2.Palabras clave: Telemedicina, Diabetes mellitus tipo 2, COVID-19  相似文献   
34.
The aim of this study was to define the histological spectrum, frequency and significance of nonconventional tumour cells in clear cell renal cell carcinomas (CCRCC). Fifty‐one totally sampled CCRCC were studied histologically to evaluate the spectrum of cell morphology variability, its frequency and significance, and their correlation with tumour grade and stage, and other histological parameters of aggressive behaviour like necrosis. Aside from conventional clear/eosinophilic granular cells, three additional cellular types were identified and considered in this study: small clear cells, syncytial cells and rhabdoid cells. Small clear cells were detected in 11 cases (21.5%), syncytial cells in 8 (15.6%) and rhabdoid cells in 5 (9.8%). The presence of syncytial and rhabdoid cells statistically correlated with grade (p = 0.003 and p = 0.006) and stage (p = 0.049 and p = 0.05) in CCRCC. Necrosis correlated with stage (p = 0.018) and grade (p = 0.004), but not with syncytial, rhabdoid or small clear cells. The presence of syncytial and rhabdoid cells in CCRCC is a relatively frequent event that significantly correlates with high‐grade tumours and high stage status.  相似文献   
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36.
Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline.  相似文献   
37.
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states.  相似文献   
38.
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites.  相似文献   
39.
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity.  相似文献   
40.
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