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Theileria parasites infect and transform bovine leukocytes. We have analyzed laboratory-established Theileria sp.-infected leukocyte lines and observed that transformed macrophages express CD5. Low-level expression of CD5 by macrophages was further confirmed on three independent Theileria annulata clinical isolates from Tunisia. Interestingly, the fourth CD5(+) clinical isolate (MB2) was morphologically different, expressed surface immunoglobulin M (IgM) and BoLA class II, and had rearranged Ig light-chain genes. To demonstrate that MB2 did indeed contain CD5(+) B cells, individual clonal lines were obtained by limiting dilution, and CD5 expression and Ig gene rearrangement were confirmed. This suggests that in natural infections T. annulata can invade and transform CD5(+) B cells.  相似文献   
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In this paper, the synthesis of Ca0.1Na0.9Ti0.1Nb0.9O3 (CNTN) ceramic by a solid-state reaction method is reported. The results of Rietveld refinement of X-ray diffraction (XRD) patterns at room temperature showed a pure tetragonal perovskite (P4mm space group). Raman spectroscopy analysis, ranging from of 50 to 1000 cm−1, at room temperature, validates the results of XRD. The dielectric properties was studied by complex impedance spectroscopy examined in broad frequency range, 100 Hz to 200 kHz, at different temperatures. The dielectric permittivity for our CNTN compound confirms the typical relaxor behavior. The investigation of the diffuseness of the transition was conducted by fitting the experimental data with modified Curie–Weiss law; Gaussian distribution and Power law confirm the presence of a short-range association between the polar nanoregions (PNRs). The obtained values of the diffuseness coefficient are of the order 1.6, which corresponds to the diffuse phase transition (DPT) ascribed to the existence of various states of polarization, thus various relaxation times in different regions. The value of diffuseness is of the order 85 and the degree of relaxor (ΔTcm = 65 K) is interesting as far as microelectric applications are concerned. Moreover, based on the frequency dependence of temperature at dielectric maxima using Vogel–Fulcher relationship, a strong evidence for a static freezing temperature with regards to thermally-activated polarization fluctuations was found.

In this paper, the synthesis of Ca0.1Na0.9Ti0.1Nb0.9O3 (CNTN) ceramic by a solid-state reaction is reported. The results of Rietveld refinement of X-ray diffraction patterns at room temperature showed a pure tetragonal perovskite (P4mm space group).  相似文献   
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The use of anticoagulants in pregnancy is problematic. In this focus, the authors reviewed the problems associated with the use of vitamin K antagonist during pregnancy. Then, they presented the general considerations on the use of unfractioned heparin and low molecular weight heparin during pregnancy. Finally they established the therapeutic recommendations for anticoagulation during pregnancy including treatment and prophylaxis of venous thromboembolism, anticoagulation of pregnant women with mechanical heart valves and the management of pregnant women with antiphospholipid antibodies and multiple pregnancy losses.  相似文献   
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INTRODUCTION: Langerhans' cell histiocytosis is a rare disorder of unknown etiology characterized by a wide clinical spectrum and varied behavior. Diabetes insipidus is a relatively common feature in Langerhans' cell histiocytosis. The presence of both diabetes insipidus and mellitus associated with histiocytosis in an adult is rare. To our knowledge, only three previous cases have been reported. EXEGESIS: We report the clinical presentation, pathologic findings and clinical progress in an adult female who had disseminated Langerhans' cell histiocytosis (hypothalamic infiltration, multifocal bone involvement) associated with both diabetes insipidus and mellitus. CONCLUSION: The pathogenesis of diabetes mellitus in such an association will be discussed.  相似文献   
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The aim of this prospective study is to evaluate the frequency of the obesity in the population of 951 children aged between 6 and 12 years old, scholarized in two primary schools situate in Ariana. We found 50 obese children between them (5.25%). The weight and the height of these children were more than 3 standards deviations compared to the normal. 66% of these children have one or two obese parents and 74% were the oldest or the youngest child in the family. The food intake was more important than the normal and it was hyperglucidic rich in sugar and hyperprotidic with troubles of dietetic comportment.  相似文献   
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