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1.
Because hypercellularity is an important feature in acute serum sickness (AcSS), we quantified glomerular proliferation with immunoperoxidase staining using anti-proliferating cell nuclear antigen (PCNA Mab) and studied its relationship with lymphocyte infiltration (M108 Mab). AcSS was induced in 31 New Zealand White rabbits; group A (n = 14), with proteinuria, sacrificed 6-8 days after immunization; group B (n = 10), without proteinuria, sacrificed 6-7 days after immunization; group C (n = 7), sacrificed prior to development of AcSS. Four normal rabbits were included as controls. Intraglomerular proliferation (PCNA-positive cells/glomerular cross section) was increased in group A (12.2 +/- SEM, 1.84) but not in groups B (0.93 +/- 0.17) and C (0.37 +/- 0.05), which were similar to controls (0.66 +/- 0.06). Lymphocyte infiltration (lymphs/glomerular cross section) increased with time and was more prominent in rabbits with proteinuria (1.9 +/- 0.21, P < 0.001 vs controls). Lymphocyte infiltration was correlated with proliferative activity (Spearman correlation, r = 0.67, P < 0.0001). There was correlation between the severity of glomerular deposition of IgG and C3 and glomerular proliferation and proteinuria. These studies demonstrate a chronological association between lymphocyte infiltration and proliferative activity in AcSS. 相似文献
2.
结合单相电子式电能表在石家庄电业局的使用情况,介绍了单相电子式电能表的特点、适用范围和选型时应注意的一些问题。 相似文献
3.
A novel noise-shifting differential Colpitts VCO is presented. It uses current switching to lower phase noise by cyclostationary noise alignment and improve the start-up condition. A design strategy is also devised to enhance the phase noise performance of quadrature coupled oscillators. Two integrated VCOs are presented as design examples. 相似文献
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Specific regulation of VLA-4 and alpha 4 beta 7 integrin expression on human activated T lymphocytes
T Hernández-Caselles M Martínez-Esparza AI Lazarovits P Aparicio 《Canadian Metallurgical Quarterly》1996,156(10):3668-3677
Modulation of VLA integrins was studied in several human T cell clones upon specific and nonspecific cellular activation. Human activated T lymphocytes down-regulated both alpha 4 beta 1 and alpha 4 beta 7 integrins upon specific recognition of alloantigens (cytotoxic T cells) or in the presence of Staphylococcus enterotoxin B (superantigen recognizing noncytotoxic T cells). In contrast, the expression of other membrane integrins, such as VLA-1 and VLA-5 integrins, was not modified. Down-regulation of alpha 4 beta 1 and alpha 4 beta 7 integrins was observed as early as 3 h after stimulation, lasted later than 72 h and was partially inhibited by cytochalasin D. Interestingly, neither target cells nor NK cells modulated CD49d expression after interaction with T cells of K562, respectively, suggesting that CD49d expression was linked to specific T cell activation. The down-regulation of the CD49d chain in T cell clones stimulated with immobilized anti-CD3 mAbs confirmed the role of TCR-mediated activation in CD49d regulation. However, the CD3-independent cellular aggregation induced by soluble anti-CD43 mAb was also able to strongly down-regulate alpha 4 beta 1 and alpha 4 beta 7. The present work shows the first evidence that CD49d subunit-bearing integrin expression is distinctly regulated from other integrins after Ag or superantigen recognition by human activated T cells. CD49d modulation may be relevant for the traffic and tissue localization of locally activated T cells during immune responses. 相似文献
6.
In this companion paper, flow patterns in the upstream and downstream tubes of a sudden-expansion cross-section (SECS) in a vertical straight pipe were presented. The effect of SECS on flow patterns upstream and downstream was analyzed by comparing with flow patterns in uniform cross-section vertical tubes. It is found the effect is great. There exist great instabilities of two-phase flow in the neighboring areas of the SECS both downstream and upstream. 相似文献
7.
Modeling of complex interfaces: Gadolinium‐doped ceria in contact with yttria‐stabilized zirconia 下载免费PDF全文
Xavier Aparicio‐Anglès Nora H. de Leeuw 《Journal of the American Ceramic Society》2017,100(7):3329-3339
Gadolinium‐doped ceria (GDC) and yttria‐stabilized zirconia (YSZ) are well‐known electrolyte materials in solid oxide fuel cells (SOFCs). Although they can be used independently, it is common to find them in combination in SOFCs, where they are used as protective layers against the formation of secondary phases or electron conduction blockers. Despite their different optimum operating temperatures, it appears that oxygen conduction is not affected by their interface. However, the intrinsic mechanisms of oxygen diffusion at these interfaces still remain unclear. One of the main difficulties when modeling the contact between different materials, or indeed different particles of the same material, is caused by the structural complexity of these systems. If we wish to evaluate the properties of the materials, we first need to obtain a model that includes the main features of the GDC/YSZ interface, such as large‐scale defects or cation interdiffusion in the contiguous phase. Since the generation of such a mixed system is complicated, we show here how the “amorphization and recrystallization” strategy can help us to obtain realistic systems. In this, the first of our papers on the structure and properties of layered GDC/YSZ materials, we discuss the structural features of the grain boundary between GDC and YSZ obtained by molecular dynamics simulations. 相似文献
8.
Rheological,Thermodynamic, and Gas Solubility Properties of Phenylacetic Acid‐Based Deep Eutectic Solvents 下载免费PDF全文
Tausif Altamash Mert Atilhan Amal Aliyan Ruh Ullah Mustafa Nasser Santiago Aparicio 《化学工程与技术》2017,40(4):778-790
Choline chloride + phenylacetic acid‐based deep eutectic solvents are studied. Their most relevant experimental physicochemical properties at different mixing ratios together with the CO2 solubility data obtained in wide pressure and temperature ranges are reported. The presented materials exhibit a significant CO2 capture performance with low corrosion effect when compared with the most common amine‐based CO2 capture agents. Detailed rheological measurements are carried out and various models are applied to describe the dynamic flow behavior of the solvents. The CO2 absorption mechanism is evaluated by studying the behavior of the liquid gas and interface. Due to the advantages of low cost, nontoxicity, and favorable physical properties, these solvents are an environmentally promising alternative for effective CO2 capture technological applications. 相似文献
9.
Guadalupe Aparicio Gallego Vanessa Medina Villaamil Enrique Grande Isabel Santamarina Ca��nzos Lu��s M. Ant��n Aparicio 《International journal of molecular sciences》2012,13(10):12710-12733
Historically, cell-signaling pathways have been studied as the compilation of isolated elements into a unique cascade that transmits extracellular stimuli to the tumor cell nucleus. Today, growing evidence supports the fact that intracellular drivers of tumor progression do not flow in a single linear pathway, but disseminate into multiple intracellular pathways. An improved understanding of the complexity of cancer depends on the elucidation of the underlying regulatory networks at the cellular and intercellular levels and in their temporal dimension. The high complexity of the intracellular cascades causes the complete inhibition of the growth of one tumor cell to be very unlikely, except in cases in which the so-called “oncogene addiction” is known to be a clear trigger for tumor catastrophe, such as in the case of gastrointestinal stromal tumors or chronic myeloid leukemia. In other words, the separation and isolation of the driver from the passengers is required to improve accuracy in cancer treatment. This review will summarize the signaling pathway crossroads that govern renal cell carcinoma proliferation and the emerging understanding of how these pathways facilitate tumor escape. We outline the available evidence supporting the putative links between different signaling pathways and how they may influence tumor proliferation, differentiation, apoptosis, angiogenesis, metabolism and invasiveness. The conclusion is that tumor cells may generate their own crossroads/crosstalk among signaling pathways, thereby reducing their dependence on stimulation of their physiologic pathways. 相似文献
10.
Santiago Aparicio 《International journal of molecular sciences》2010,11(5):2017-2038
17 selected flavones derivatives, flavonoids, were analyzed through a systematic B3LYP/6-311++G** computational study with the aim of understanding the molecular factors that determine their structural and energetic properties in gas phase. Flavonoids were selected in a systematic way to infer the effect of the number and relative positions of hydroxyl groups on molecular properties. Different conformers for each flavonoid were analyzed and the strength and topology of the intramolecular hydrogen bonds studied through the computation of the corresponding torsional profiles. Atoms in a Molecule, and Natural Bond Orbital methodology was applied to the analysis of charge distribution along the studied molecules, and the intramolecular hydrogen bonds. Molecular shapes were studied through full geometry optimization, and the position of the catechol ring analyzed through dihedral scans. 相似文献