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261.
Graft-versus-host disease (GvHD) includes inflammatory and/or fibrosing manifestations that may arise at various times after transplantation of any organ containing lymphoid cells. For the dermatologist, the importance of GvHD is real and current. Indeed, because it has become easier to perform bone marrow transplantation (EMT), the indications of BMT have become broader, making follow-up of patients receiving grafts a widespread practice. Nonetheless, GvHD remains a frequent complication of BMT and its principal target organ is the skin. Furthermore, recent innovations, such as grafting of umbilical cord blood and the mobilization of peripheral blood progenitor cells, will be the source of new questions concerning the development of GvHD under these conditions. Finally, because of its analogies with other spontaneous idiopathic skin diseases, GvHD constitutes a model that may lead to a better understanding of the pathophysiological features of these diseases. In this review, the cutaneous aspects of GvHD are emphasized. 相似文献
262.
263.
The authors present a biosensor intended to evaluate prostatic stiffness. The stiffness of the prostate was modulated using hormonal induction and adrenergic stimulation. The results show that the sensor can be sufficiently accurate to discriminate between soft prostates used as controls and those stiffened with hormones. The modulation produced by an adrenergic agent on prostatic stiffness was detected using this system. An electrical model was constructed embodying the parameters of prostatic stiffness, micturition frequency, and volume, demonstrating that prostatic stiffness correlates with micturition frequency 相似文献
264.
H Akoum C Duez H Vorng O Fahy B Wallaert AB Tonnel A Tsicopoulos 《Canadian Metallurgical Quarterly》1998,10(9):706-712
The mechanism by which specific immunotherapy exerts its beneficial effect remains unclear. Chemokines are implicated in inflammatory and allergic diseases, in particular via their ability to induce histamine release from basophils, a potential early target of rush venom immunotherapy (RVIT), In this study, the authors evaluated ex vivo regulated upon activation normal T-cell expressed and secreted (RANTES), interleukin 8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1) production and mRNA expression by mononuclear cells (MNC) from nine patients undergoing a 3.5-h ultra rush treatment, before treatment at Day 0 (D0), at the end of the 3.5-h of the rush at Day 4h (D4h), at Day 15 (D15) and Day 45 (D45) after treatment. Increased RANTES release and mRNA expression were observed in 24-h culture of peripheral blood MNC collected at D4h. This was followed by a decrease in the production of RANTES, IL-8 and MCP-1, 45 days after initiation of RVIT. The same pattern was observed after in vitro venom stimulation of MNC. At the mRNA level, similar profiles were observed except for IL-8 mRNA which inversely increased during RVIT. These results suggest that RVIT is associated with a general decrease in chemokines which may explain, in part, the clinical efficacy of specific immunotherapy. 相似文献
265.
266.
W Zorzi O Thellin B Coumans F Melot G Hennen B Lakaye A Igout E Heinen 《Canadian Metallurgical Quarterly》1998,19(4):269-277
Thrombopoietin (TPO) or Mpl ligand is the primary physiological regulator of platelet production. This cytokine is the most potent stimulator of the proliferation and differentiation of MK progenitor and precursor cells in vitro. It also acts additively or synergistically with several cytokines on progenitor cells from various hematopoietic lineages, including the primitive stem cells. The factor is an extremely potent thrombocytopoietic agent when administrated to normal animals, and it accelerates platelet and erythropoietic recovery in several models of myelosuppression. Phase I/II clinical trials are ongoing with no detectable adverse effects. Mpl ligand does not induce platelet aggregation, but it lowers the platelet sensitivity to physiological dose of agonists. In experimental mouse models, high and chronic dose of Mpl ligand results in myelofibrosis. TPO is constantly produced by the liver and the kidney; its plasmatic clearance occurs by binding to its receptor expressed on megakaryocytes and platelets. However, the full spectrum of the biological effects of this new cytokine is not fully understood, in particular its the role in the terminal stage of platelet production. In the near future, it is likely that new insights will be obtained in the physiopathological mechanisms underlying abnormal platelet production in human. 相似文献
267.
T. A. Bykhovskaya K. P. Zakharova T. T. Karpova O. L. Masanov A. A. Orlova O. M. Khimchenko 《Atomic Energy》1995,79(3):606-608
Main Science Center of the Russian Federation, A. A. Bochvara All-Russia Scientific-Research Institute of Standardization
in Machine Engineering. Atomnaya énergiya, Vol. 79, No. 3, pp. 197–200, September, 1995. 相似文献
268.
The β and γ decay of uranium atoms from xUO3(100 - x)[3B2O3 · MO] glass systems, where M=Sr or Pb and 0 ≤ × ≤ 20 mol%, is investigated. The γ decay data are very close to each other, for the same UO3 contents, in both the systems. The composition dependence of the β decay exhibits a lower slope in the lead borate matrix than in the strontium borate matrix. The ratio between the β activity of samples with the same uranium ion concentrations in the two investigated glass systems is a function of the x values. The results are correlated with the amount of radioactive nuclides and with the structural environments of the radionuclides. The leaching treatment in water at temperatures below 100°C evidenced no aqueous dissolution of glass samples. 相似文献
269.
A dilatometer for measuring autogenous deformation in hardening portland cement paste 总被引:1,自引:1,他引:0
Different techniques for measuring autogenous deformation in cement paste are discussed, and a newly developed dilatometer designed specially for measuring this deformation is described. A particular characteristic of the dilatometer is the encapsulation of the cement paste in corrugated moulds. This restricts moisture loss and ensures that the hardening cement paste suffers insignificant restraint. In addition, the encapsulation permits measurements to commence shortly after casting. 相似文献
270.
V. M. Polyanskii N. I. Volkov O. M. Gorodkova Yu. N. Kopanov T. A. Frol'tsova A. N. Khailov 《Strength of Materials》1990,22(1):59-70
Direct data have been obtained for the creep of high- and medium-strength aluminum alloys in the stress range of O.6–1.2 of the nominal yield strength 0.2 in laboratory air and in aqueous NaCl solution at room temperature. On this basis using known theories approximating functions have been determined for the creep curves. Stress 0.2 serves as a natural boundary for the macroelastic and macroplastic regions in the first of which creep is only transient, and in the second there are transient, quasisteady-state, and accelerated stages. Extrapolated estimates of creep strain in the macroelastic region from data measured in the macroplastic region are not physically competent. However, a tendency towards an increase in ductility with an increase in time to failure at stresses greater than o.2 makes it possible to estimate by extrapolation the time for onset of the accelerated creep stage with low test stresses from measured values at greater stresses in the macroplastic region. Fractographic and strain indices revealed the harmful effect of moist atmospheres on the deformation and failure resistance of alloys with prolonged loading.Translated from Problemy Prochnosti, No. 1, pp. 50–58, January, 1990. 相似文献