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71.
KL Komschlies TA Gregorio ME Gruys TC Back CR Faltynek RH Wiltrout 《Canadian Metallurgical Quarterly》1994,152(12):5776-5784
These studies investigate the effects of exogenously administered recombinant human IL-7 (rhIL-7) on mouse leukocyte subsets in vivo in normal and tumor-bearing mice. The administration of rhIL-7 to normal mice caused a pronounced leukocytosis (three- to fivefold increase over background) in the spleen and lymph nodes, with B-lineage and T cells, NK cells, and macrophages all being increased. CD8+ T cells increased disproportionately, such that the CD4 to CD8 ratio decreased dramatically. The rhIL-7-induced effects were dose-dependent, increased with duration of treatment, and were reversible after cessation of rhIL-7 administration. T cell number increases after rhIL-7 treatment were primarily a result of an expansion of the peripheral T cell population. Importantly, splenocytes from rhIL-7-treated mice have enhanced proliferative responses to various T cell stimuli in vitro and were able to potentiate an allogeneic CTL response in vivo. The rhIL-7-induced changes in T cell number and the CD4 to CD8 ratio also were observed in mice bearing early Renca renal adenocarcinoma pulmonary metastases, and these changes coincided with up to a 75% reduction in pulmonary metastases. Overall, these results demonstrate that the administration of rhIL-7 to mice profoundly increases the number of B and T cells, and reduces the number of pulmonary metastases. The results also suggest that IL-7 may be useful for restoring lymphoid subsets in immunosuppressed hosts and in enhancing T cell-mediated immune responses. Such effects may be useful in the treatment of microbial diseases and cancer. 相似文献
72.
73.
In this article we make a critical analysis of the model proposed by Weber, present an improvement that gives the logarithmic correction on the shape of sandpiles properly, and study the normal forces on the surface supporting a pile using the improved model. 相似文献
74.
The letter describes how a magnetostatic constant delay line can be designed and practically realised by using two identical dispersive delay lines operating with forward volume waves and frequency-inverting one of the band responses. 相似文献
75.
M Virno L Taverniti F De Gregorio L Sedran F Longo 《Canadian Metallurgical Quarterly》1996,20(1-3):141-146
BACKGROUND: Topically administered 2% ibopamine (a dopaminergic agonist) induces a transitory ocular hypertension in 92% of patients with primary open-angle glaucoma and in 52% of patients with normal tension glaucoma. In normal eyes, ibopamine has no effect on IOP. PURPOSE: The aim of the present study was to verify, by means of fluorophotometric techniques, which hydrodynamic changes could be induced in normal and glaucomatous eyes, stimulating the D1 receptor with 2% ibopamine administered topically. In addiction, we wanted to evaluate if ibopamine could modify IOP before and after an experimentally induced outflow system impairment in rabbits. METHODS: In study 1 we performed a measurement of aqueous humor flow in 6 healthy volunteers and in 6 glaucomatous patients, before and after 2% ibopamine administration. In study 2 the alteration of outflow pathways was induced by means of Laminaria Digitata in 10 rabbits. RESULTS: After 2% ibopamine administration we found a significant increase in aqueous humor production, both in glaucomatous (P = 0.035) and normal eyes (P = 0.004). In rabbits, we found no significant change in IOP at basal conditions. After experimentally induced outflow system impairment by laminaria, we observed a marked increase in IOP (+ 13.5 mmHg SD 7.2; P < = 0.001) following ibopamine administration. CONCLUSIONS: These experimental data have a diagnostic value in glaucoma, since they show how an intraocular hypertensive response due to ibopamine in normotensive eyes is a sign of initial outflow impairment. Moreover, the possibility to increase the aqueous humor production sets new trends in the treatment of post surgical ocular hypotony. 相似文献
76.
Multimedia information broadcasting using digital TV channels 总被引:1,自引:0,他引:1
Atzori L. De Natale F.G.B. Di Gregorio M. Giusto D.D. 《Broadcasting, IEEE Transactions on》1997,43(3):242-251
The structure of a new system used to broadcast multimedia information within a digital TV channel is outlined. The proposed scheme is based on the the Digital Storage Media Command and Control (DSM-CC) functions, and uses a newly developed protocol that allows to efficiently convey multimedia information. Such information has the same characteristics of HTML files used in WWW environments, as it may contain text, images, sounds and animation organized as an hypertext. The transport structure used is the MPEG-2 Transport Stream, which is the most standardized platform for the development of new digital TV services. A prototype software was developed to encode the file system by means of DSM-CC operations and include it in a MPEG-2 compatible Transport Stream 相似文献
77.
Y Ma G Gregorio J G?ken L Muratori FB Bianchi G Mieli-Vergani D Vergani 《Canadian Metallurgical Quarterly》1997,26(6):1396-1402
78.
79.
Mara L. Polo Marisa E. Spontón Franklin Jaramillo Diana A. Estenoz Gregorio R. Meira 《应用聚合物科学杂志》2018,135(4)
This work investigates the two‐step polymerization between methylene diphenyl diisocyanate (MDI), two different poly(tetramethylene oxide) macrodiols, and 1,4‐butanediol (BD) as chain extender. At the end of the prepolymerization, the reaction mixture contains MDI in excess and a prepolymer with isocyanate end group. Then, BD and a solvent (tetrahydrofuran) were added to start the finishing stage under nominal stoichiometric equilibrium. The reaction was analyzed by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H‐NMR), and size exclusion chromatography. 1H‐NMR was employed to follow global concentrations of unreacted isocyanate end groups and internal urethane groups. This information enabled to estimate the following “effective” rate constants: k1 = 1.07 × 10?3 L mol?1 s?1 for the prepolymerization; and k2 = 1.94 × 10?4 L mol?1 s?1 for the finishing stage. These values are subject to errors caused by biases introduced in the recipe, in the measurements, in the reaction conditions, in the quality of reagents, and in the reaction mechanism assumptions. Such errors also explain the dispersion of the published rate constants values. The 1H‐NMR measurements also enabled to estimate the evolution (with extent of reaction) of the number‐average number of structural units along the prepolymerization and finishing stages; and such estimates reasonably verify Flory's classical expressions. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45747. 相似文献
80.
Enrique Chirivella-Perez Ricardo Marco-Alaez Alba Hita Ana Serrano Jose M. Alcaraz Calero Qi Wang Pedro M. Neves Giacomo Bernini Konstantinos Koutsopoulos Manuel Gil Pérez Gregorio Martínez Pérez Maria João Barros Anastasius Gavras 《Software》2020,50(5):741-756
This paper presents the design and prototype implementation of the SELFNET fifth-generation (5G) mobile edge infrastructure. In line with the current and emerging 5G architectural principles, visions, and standards, the proposed infrastructure is established primarily based on a mobile edge computing paradigm. It leverages cloud computing, software-defined networking, and network function virtualization as core enabling technologies. Several technical solutions and options have been analyzed. As a result, a novel portable 5G infrastructure testbed has been prototyped to enable the preliminary testing of the integrated key technologies and to provide a realistic execution platform for further investigating and evaluating software-defined networking– and network function virtualization–based application scenarios in 5G networks. 相似文献