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1.
Fifty-six patients with recurrent bronchopulmonary infections associated with chronic bronchitis were randomly allocated to 2 groups, to assess whether treatment with an immunomodulator, Diribiotin CK, could enhance resistance to infection. The double-blind, placebo-controlled prospective trial over a 9 month period showed that this immunomodulator was well tolerated and significantly reduced the rate of respiratory tract infection. The drug also significantly reduced the prescribing of antibiotic medication and the rate of absenteism from work. These effects have been demonstrated in a rigorously designed clinical study. This is the first time that a clear clinical activity has been attributed to an inducer of soluble mediators of immunity.  相似文献   
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Cytomegalovirus (CMV) antigenemia was directly detected in polymorphonuclear leukocytes (PMNLs) from transplant recipients by using flow cytometry (FC). Two fixation and permeabilization methods and seven anti-CMV monoclonal antibodies (MAbs) were evaluated. 1C3, SL20, and NEA-9221 MAbs were more efficacious. The antigenemia detection threshold of FC was 0.05% positive PMNLs, and percentages correlated well with DNA viral load and the appearance of clinical symptoms.  相似文献   
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Summary: Multiple myeloma (MM) is a plasma cell malignancy mainly characterized by the accumulation of malignant plasma cells within the bone marrow. This review shows that the biology of CD45 illuminates that of MM and, more specifically, provides a better delineation of a tumor cell ‘hierarchy’ of clinical interest. We show that in MM, as in normal plasma cell differentiation, there is an intraclonal CD45 hierarchy that is a gradient of CD45 expression on myeloma cells directly related to their proliferation rate and differentiation status. This CD45 hierarchy allows for the design of a cellular model for MM‐cell growth and maturation in which CD45 bright myeloma cells represent the proliferating compartment and CD45 low myeloma cells the quiescent compartment. This model includes an aberrant phenotype that is annihilation rather than decline of CD45, annihilation reflecting the terminal phase of the disease and/or an aggressive presentation of MM. Data from the literature suggest that CD45 bright myeloma cells are targeted by interleukin (IL)‐6, whereas CD45 negative myeloma cells with a high clonogenic capacity are targeted by insulin/insulin‐like growth factor 1 (IGF‐1). This model will be useful for both a better understanding of the basic biology of MM and a better stratification of and therapeutic approach to the patients. Finally, this model presents MM as a self‐renewing plasma cell disease, although the first oncogenic events such as 14q32 translocations clearly occur earlier in a B cell.  相似文献   
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A technique that allowsin vivo measurements of the specific impedance of brain structures is analysed and implemented. This technique uses the 4-electrode method. The system includes an optically isolated current source and an interchangeable electrode module. Tests on the measuring system, including the electrodes and calibration procedures, are presented. Experiments in media of known resistivity and in cat brains define the present limits of the spatial resolution.  相似文献   
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Reclaru L  Lerf R  Eschler PY  Blatter A  Meyer JM 《Biomaterials》2003,24(18):3027-3038
The corrosion behavior of titanium with vacuum plasma sprayed titanium coatings and with anodized surfaces, both with and without polymeric bone cement were evaluated. Electrochemical extraction tests were carried out with subsequent analysis of the electrolyte by ICP-MS in order to verify our hypothesis of the ionic permeability of the polymer cement. The complexity of the situation resides in the existence of two interfaces: electrolyte-polymer and polymer-metal. The surface preparation (treatment of the surface) plays an important role in the corrosion resistance of titanium. The electrochemical magnitudes that were examined reveal that the plasma spray surfaces have the lowest corrosion resistance. The cement, in spite of having reduced electrical conductivity in comparison to metal, is an ionic transporter, and therefore capable of participating in the corrosion process. In the present study, we observed in fact crevice corrosion at the metal-cement interface. In the case of plasma spray surfaces, a process of diffusion of titanium particles in the electrolyte could accompany the crevice corrosion. In this study, we have shown that there is a corrosion process at the surface of the titanium through the cement which has as a consequence on the one hand the formation of titanium cations and on the other hand the growth of a passive layer on the titanium. In conclusion, we identified two principal factors that influence the corrosion process: [1] the type of surface treatment for the titanium, and [2] the ionic conductivity of the cement. There is indeed ionic transport through the cement; as evidenced by the presence of titanium in the electrolyte solution (ICP-MS analysis) and chloride at the surface of the titanium sample (EDX analysis).We show that the polymer cement is an ionic conductor and participates in the corrosion of the embedded titanium. We cannot deduce from our results, however, whether the polymer itself possesses corrosive properties. Long-term experiments will be necessary to study the degradation behavior of the polymer cement.  相似文献   
8.
Enzyme immunoassays (EIAs) using synthetic peptides SP-E1 and SP-E1E2 (DETECT-RUBELLA [Bio-Chem]) were compared with two viral lysate-based EIAs (Enzygnost [Behring] and IMx [Abbott]) for the detection of rubella virus-specific immunoglobulin G antibodies. Sensitivities of 94.7, 100, 98.6, and 100% and specificities of 100, 97.4, 100, and 73.7% were found for the SP-E1, SP-E1E2, Enzygnost, and IMx EIAs, respectively.  相似文献   
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The present review summarizes recent studies describing the role of renal sympathetic innervation in the regulation of renal function during development. The afferent renal innervation appears early during fetal life and probably precedes the development of efferent renal nerves. There is suggestive evidence that renal nerves are required for the proper development of the kidney and that neurotrophic growth factors play an important role in renal embryogenesis and in renal tubular differentiation. Renal sympathetic innervation modulates renal hemodynamics early during development. Renal nerve stimulation during -adrenoceptor blockade produces renal vasodilation in fetal and newborn animals but not in adults. Unlike the effect of renal nerves on fetal renal hemodynamics which is observed in the young fetus, the role of renal sympathetic nerves in modulating fluid and electrolyte homeostasis seems to develop during late gestation. Recent studies have also shown that renal nerves play an important role in regulating renin secretion during the transition from fetal to newborn life. For example, renal denervation during fetal life suppressed the physiological rise in plasma renin activity associated with delivery and decreased renal renin mRNA levels after birth. Taken together, these studies suggest that renal nerves influence fetal renal development and that the influence of renal sympathetic innervation on renal hemodynamics and function changes with maturation.  相似文献   
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