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971.
972.
973.
974.
Osteopontin in chronic puromycin aminonucleoside nephrosis 总被引:1,自引:0,他引:1
Increased expression of osteopontin (OPN) associated with interstitial monocyte infiltration has been demonstrated in the early phase of a variety of experimental renal diseases. Whether these changes occur in the chronic phase of progressive glomerular disease is unknown. Chronic puromycin aminonucleoside nephrosis (PAN) was induced in 16 rats by the injection of a single bolus of PA into the internal jugular vein, which results in a triphasic disease characterized by minimal glomerular change and marked proteinuria, peaking at about 10 to 14 d and subsiding by 28 d, followed by a quiescent 4-wk period of no or minimal proteinuria and then the development of progressive focal glomerulosclerosis (FGS) and increasing proteinuria. Fifteen rats injected similarly with normal saline served as controls. At 11 d after injection, PA rats demonstrated significantly greater urinary protein excretion (P = 0.0107), cortical tubular OPN expression (P = 0.0086), and intraglomerular (P = 0.0009) and interstitial (P = 0.0212) monocyte infiltration than did the controls. At 42 d, no significant differences between the two groups with respect to the above parameters were detected. At 98 d, PA rats had FGS and showed a definite trend to increased proteinuria, cortical tubular OPN, and intraglomerular monocyte infiltration. Although the cortical interstitial monocyte count was not elevated in PA rats compared with controls, there were significantly more monocytes around OPN-positive cortical tubules than around OPN-negative ones (P = 0.0011). Cortical tubular OPN expression correlated well with urinary protein excretion (r = 0.932, P < 0.0001), cortical tubular proliferating cell nuclear antigen (r = 0.796, P < 0.0001), and intraglomerular monocyte count (r = 0.552, P = 0.0013). The results are consistent with a monocyte chemoattractant role for OPN and suggest that OPN is upregulated in the chronic phase of PAN and that this increase in expression is a result of glomerular events. 相似文献
975.
The para-toluene sulfonic acid (p-TSA) was used to catalyze the moisture curing of an organic/inorganic hybrid coating system. The organic phase was based on the isocyanurate of 1,6-hexamethylene of diisocyanate (HDI). The inorganic phase was based on the prepolymerized oligomers of tetraethyl orthosilicate (TEOS). An alkoxysilane-functionalized HDI isocyanate was added into the coating formulation to aid in phase miscibility. The general coating and tensile properties were evaluated as a function of the acid catalyst concentration. In addition, the films were analyzed using differential scanning calorimetry (DSC) and dynamical mechanical thermal analysis (DMTA). The results indicated that the acid catalyst enhanced the adhesive properties of the hybrid coatings. The addition of the acid catalyst increased the changed crosslink density of films and decreased the crystallinity of the organic phase. 相似文献
976.
Regular variation is an analytic condition on the tails of a probability distribution which is necessary for an extended central limit theorem to hold, when the tails are too heavy to allow attraction to a normal limit. The limiting distributions which can occur are called operator stable. In this paper we show that moving averages of random vectors with regularly varying tails are in the generalized domain of attraction of an operator stable law. We also prove that the sample autocovariance matrix of these moving averages is in the generalized domain of attraction of an operator stable law on the vector space of symmetric matrices.
AMS 1990 subject classification. Primary 62M10, secondary 62E20, 62F12, 60F05. 相似文献
AMS 1990 subject classification. Primary 62M10, secondary 62E20, 62F12, 60F05. 相似文献
977.
Watson Deborah J.; Herbert Mariel R.; Stanton Mark E. 《Canadian Metallurgical Quarterly》2009,123(1):44
Two experiments examined the effect of the noncompetitive NMDA receptor antagonist, dizocilpine maleate (MK-801), on spatial working memory during development. Rats were trained on spatial delayed alternation (SDA) in a T-maze after ip administration of 0.06 mg/kg MK-801, 0.1 mg/kg MK-801, or saline on postnatal days (P) P23 and P33 (Experiment 1), or following bilateral intrahippocampal administration of 2.5 or 5.0 υg per side MK-801 or saline on P26 (Experiment 2). In Experiment 1, MK-801 dose-dependently impaired SDA learning at both ages. Because the same doses of systemic MK-801 have no effect on T-maze position discrimination learning, impairment of SDA by MK-801 likely reflects disruption of spatial working memory. Both doses of MK-801 abolished acquisition of SDA performance in Experiment 2. Disruption of hippocampal plasticity may account for the effects produced by systemic MK-801 administration. These results confirm and extend earlier lesion studies by implicating plasticity of hippocampal neurons in the ontogeny of spatial delayed alternation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
978.
This article describes a new perceived whiteness index, C/V index, which focuses on the brightness‐enhancement effect of color components included in the spectral reflectance factor distribution of approximate white objects or in the spectral power distribution of illuminations. The index is developed on the basis of a color vision model. The perceived whiteness of 18 approximate white samples was evaluated, and then a predictability of the index was compared with 17 types of existing whiteness indices. As a result, the C/V index was one of the indices indicating the best predicting performance. The aforementioned findings show that the C/V index is effective in evaluating the perceived whiteness of approximate white objects and the brightness‐enhancement effect of color components is an important factor in determining the perceived whiteness. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010 相似文献
979.
The Unified Problem-Solving Method
Development Language UPML 总被引:2,自引:1,他引:2
980.
MP Scolnik MF Palacios SH Acevedo MV Castuma IB Larripa A Palumbo EB Moiraghi AM Sasot AB Huberman 《Canadian Metallurgical Quarterly》1998,31(1-2):231-236
The murine monoclonal antibody A7 (MAb A7) is reactive against most human gastric cancer cell lines. Using a nude mouse peritoneal dissemination model of human gastric cancer, we investigated targeted chemotherapy using a conjugate of neocarzinostatin (NCS) with MAb A7 (A7-NCS). After demonstrating cytotoxicity of the complex against the human gastric cancer cell line MKN45 in vitro, we intraperitoneally injected A7-NCS, NCS or saline into nude mice bearing peritoneally disseminated human gastric cancer. A7-NCS inhibited peritoneal dissemination significantly more effectively than NCS. MAb A7 may prove to be an effective carrier for antineoplastic drugs in patients with peritoneal dissemination of gastric cancer. 相似文献