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131.
Fatin N. Mohd Jaya Sergio G. Garcia Francesc E. Borras Dolores Guerrero Godfrey C. F. Chan Marcella Franquesa 《International journal of molecular sciences》2021,22(9)
Regulatory B (Breg) cells are endowed with immune suppressive functions. Various human and murine Breg subtypes have been reported. While interleukin (IL)-10 intracellular staining remains the most reliable way to identify Breg cells, this technique hinders further essential functional studies. Recent findings suggest that CD9 is an effective surface marker of murine IL-10 competent Breg cells. However, the stability of CD9 and its relevance as a unique marker for human Breg cells, which have been widely characterized as CD24hiCD38hi, have not been investigated. Here, we demonstrate that CD9 expression is sensitive to in vitro B cell stimulations. CD9 expression could either be re-expressed or downregulated in purified CD9-negative B cells and CD9-positive B cells, respectively. We found no significant differences in the Breg differentiation capacity of the CD9-negative and CD9-positive B cells. Furthermore, CD9-positive B cells co-express CD40 and CD86, suggesting their nature as B cell activation or co-stimulatory molecules, rather than regulatory ones. Therefore, we report the relatively unstable CD9 as a distinct surface molecule, indicating the need for further research for a more reliable marker to purify human Breg cells. 相似文献
132.
Conclusion Separation of martensitic transformation into several stages in martensitic corrosionresistant steels may be explained by a concentration gradient for carbon and carbide-forming elements in austenite as a result of precipitation of them during cooling.Spain. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 7–8, July, 1991. 相似文献
133.
Silicon Nitride Derived from an Organometallic Polymeric Precursor: Preparation and Characterization 总被引:1,自引:0,他引:1
Wayde R. Schmidt Vijay Sukumar William J. Hurley Jr. Roberto Garcia Robert H. Doremus Leonard V. Interrante Gary M. Renlund 《Journal of the American Ceramic Society》1990,73(8):2412-2418
Partially crystalline Si3 N4 , with nanosized crystals and a specific surface area greater than 200 m2 /g, is obtained by pyrolysis of a commercially available vinylic polysilane in a stream of anhydrous NH3 to 1000°C. This polymer does not contain N initially. Crystallization to high-purity α-Si3 N4 proceeds with additional heating above 1400°C under N2 . The changes in crystallinity, powder morphology, infrared spectra, and elemental compositions, for samples annealed from 1000° to 1600°C under N2 , are consistent with an amorphous-to-crystalline transformation. Although macroscopic consolidation and local densification occur at 1400°C, volatilization and accompanying weight loss limit bulk densification. The effect of temperature on specific surface area is examined and related to the sintering process. These results are applicable to pyrolysis, decomposition, and crystallization studies of ceramics synthesized by polymeric precursor routes. 相似文献
134.
M. T. Garcia J. Sanchez Leal I. Ribosa 《Journal of the American Oil Chemists' Society》1992,69(1):20-24
The influence of various experimental parameters on the flux of sodium dodecyl sulfate (SDS) through a collagen membrane has
been studied. The variables evaluated were donor concentration, time, temperature, pH and ionic strength. Data on the influence
of both surfactant concentration and time on surfactant diffusion through the collagen film allow one to postulate a diffusion
process mainly of the monomeric type. This diffusion mechanism based on surfactant monomers has been corroborated by studying
the effect of ionic strength. Thisin vitro technique could be a useful tool to predict the effect of diverse experimental parameters on the percutaneous absorption
of surfactants. 相似文献
135.
Filiberto González Garcia Bluma G. Soares Victor J. R. R. Pita Rubén Sánchez Jacques Rieumont 《应用聚合物科学杂志》2007,106(3):2047-2055
The mechanical properties of epoxy networks based on diglycidyl ether of bisphenol A epoxy resin cured with various linear aliphatic amines, such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and cyclic amines such as 1‐(2‐aminoethyl)piperazine and isophorone diamine, were studied. General characteristics such as Tg, density, and packing density, were determined and related to the structure and funcionality of the curing agent. Dynamic mechanical spectra were used to study both the α and β relaxations. Tensile and the flexural tests were used to determine the Young's and flexural modulus, and fracture strength all in the glassy state. Furthermore, linear elastic fracture mechanics was used to determine KIC. As a rule, isophorone diamine network presented the higher tensile and flexure modulus while 1‐(2‐aminoethyl)piperazine gave the highest toughness properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
136.
Palmitoyl CoA-glycerol-3-phosphate acyltransferase, phosphatidate phosphohydrolase, and phospholipase A were assayed in subcellular
fractions of rat lung, including lamellar bodies, the putative site of storage and secretion of lung surfactant. The specific
activity of each of these enzymes in lamellar bodies was relatively low and could be entirely accounted for by a small contamination
of the lamellar bodies fraction by microsomes, as quantitated by the presence of the microsomal marker reduced triphosphopyridine
nucleotide cytochromec reductase. These data indicate that lamellar bodies are not the site of synthesis of the lipid component of pulmonary surfactant
by pathways involving these enzymes. 相似文献
137.
Luis A. Garcia Maria Antonieta Alfaro Ricardo Bressani 《Journal of the American Oil Chemists' Society》1987,64(3):371-375
Oils from a selection ofAmaranthus caudatus, A. hypochondriacus andA. cruentus were extracted with hexane. The crude oils were analyzed for acid value, saponification and iodine number, and were included
in basal casein diets for rat studies at 5 and 10% levels to replace equal amounts of refined cottonseed oil. The oils fromA. cruentus andA. hypochondriacus were similar in the oil properties studied and different fromA. caudatus. At either 5 or 10% food intake levels, weight gain and PER were not statistically different from values reported for cottonseed
oil. True digestibility of amaranth oil was lower than that of cottonseed oil.A. cruentus oil gave the lowest digestibility. Oil levels induced statistical differences in food intake and digestibility. Oils fromA. caudatus, A. hypochondriacus and cottonseed induced similar serum cholesterol levels, while oil fromA. cruentus gave statistically higher values. Hemoglobin, hematocrit and serum proteins were similar among all groups. Microscopic analysis
of the organs of the rats revealed some changes that were also found in cottonseed oil-fed rats. It was concluded that crude
amaranth oil has lower digestibility than cottonseed oil, but that it is not responsible for growth-depressing effects when
the seed is fed raw as compared to processed materials. 相似文献
138.
HY zeolites catalyze the crossed aldol condensation of acetophenone with benzaldehyde, in benzene at 80 °C, to give trans- and cis-chalcones. Together with these expected products, 3,3-diphenylpropiophenone is also produced. In the analogous basic condensation, using phase transfer catalysis, the Michael adduct was not detected, and besides chalcone a small percentage of the Cannizzaro reaction product was observed. 相似文献
139.
Symmetries in constraint problems present an opportunity for reducing search. This paper presents Lightweight Dynamic Symmetry Breaking, an automatic symmetry breaking method that is efficient enough to be used as a default, since it never yields a major slowdown while often giving major performance improvements. This is achieved by automatically exploiting certain kinds of symmetry that are common, can be compactly represented, easily and efficiently processed, automatically detected, and lead to large reductions in search. Moreover, the method is easy to implement and integrate in any constraint system. Experimental results show the method is competitive with the best symmetry breaking methods without risking poor performance. 相似文献
140.
We analyze the complexity of equilibria problems for a class of strategic zero-sum games, called angel-daemon games. Those games were introduced to asses the performance of the execution of a web orchestration on a moderate faulty or under stress environment. Angel-daemon games are a natural example of zero-sum games whose representation is naturally succinct. We show that the problems of deciding the existence of a pure Nash equilibrium or of a dominant strategy for a given player are ${\Sigma}^{p}_{2}$ -complete. Furthermore, computing the value of an angel-daemon game is EXP-complete. Thus, our results match the already known classification of the corresponding problems for the generic families of succinctly represented games with exponential number of actions. 相似文献