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排序方式: 共有921条查询结果,搜索用时 265 毫秒
821.
J. N. Bryan H. Mohsin F. Jia C. B. Siegall C. J. Anderson W. H. Miller C. J. Henry M. R. Lewis 《Veterinary and comparative oncology》2004,2(2):99-99
Objectives: We previously presented preliminary data on pilot biodistributions of 64Cu‐labeled monoclonal antibodies (mAbs). 1 The purpose of the present studies was to obtain comprehensive biodistributions using a two‐antibody model for direct comparison of an internalizing and a non‐internalizing mAb in the same animal model of cancer. These studies will allow evaluation of the efficacies of the two 64Cu‐labeled mAbs for radioimmunotherapy (RIT) and are part of a larger, ongoing project examining the unusual tumoricidal properties of internalized 64Cu. Methods: DOTA (1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid) was conjugated to an internalizing antibody, cBR96, and a non‐internalizing antibody, cT84.66. Biodistributions of the 64Cu‐labeled conjugates in nude mice bearing LS174T human colorectal carcinoma xenografts were obtained at time points from 15 min to 48 h. Mouse tumor dosimetry was calculated using a Monte Carlo N‐Particle Transport Code. Results: The 64Cu‐DOTA‐cBR96 conjugate demonstrated rapid tumor uptake, reaching 20.2% injected dose per gram of tissue (% ID/g) at 3 h and peaking at 35.4% ID/g by 24 h. Tumor accumulation of 64Cu‐DOTA‐cT84.66 was more gradual, 8.19% ID/g at 3 h (p = 0.002), and reached 43.8% ID/g by 24 h, but maximum uptake was not statistically different from 64Cu‐DOTA‐cBR96 (p = 0.05). Liver, spleen, and kidney uptakes were statistically similar at 24 h for both conjugates (p = 0.05). Tumor absorbed radiation doses were estimated to be 1128 rad/mCi for 64Cu‐DOTA‐cBR96 and 1409 rad/mCi for 64Cu‐DOTA‐cT84.66. Conclusion: The biodistributions and tumor dosimetry of these two radiolabeled antibodies were sufficiently similar for direct comparison of the therapeutic efficacies of internalizing versus non‐internalizing 64Cu RIT agents in the same animal model of cancer. RIT studies using this two‐antibody model are currently in progress to test the hypothesis that internalization of 64Cu is necessary for enhanced cytotoxic properties at low tumor absorbed doses. 相似文献
822.
Henry Wai‐Chung Yeung 《Asia Pacific viewpoint》2007,48(1):1-25
Abstract: This paper aims to explain how a number of leading electronics firms from Asian newly industrialised economies of Hong Kong, Singapore, South Korea and Taiwan are articulated into global production networks and become major players in their respective market niches. Developing a triangular theoretical framework, I seek to explain the complex relationships between the dynamic articulation of these leading Asian electronics firms into different global production networks and their simultaneous upgrading from typical followers to market leaders. As a critique of the dominant developmental state discourse, I argue that the interplay between corporate strategies and home base advantages within the context of changing global production networks can offer a better explanation of the differentiated competitive outcomes of these Asian firms. This paper draws upon original data collected through personal interviews with top executives from leading electronics firms in the four Asian newly industrialised economies. I conclude the paper with some implications for theory and policy in relation to corporate development in Asian economies. 相似文献
823.
Using Plastinated Specimens in Teaching Veterinary Anatomy 总被引:1,自引:0,他引:1
R. W. Henry 《Anatomia, histologia, embryologia》2005,34(S1):17-17
Aim: The aims of this study were immunhistochemical (IHC) and ultrastruktural characterization of cells involved in vaccine granuloma formation in Atlantic salmon.
Methods: Fish suffering from severe reaction 6 to 9 months after vaccination were selected. We investigated granuloma from peritoneum, at the injection site. Morphological staining techniques, IHC to visualise MHC+ cells and ultrastructural analysis were performed.
Results: Microbial investigations revealed no infective agents. Histological and ultrastructural studies revealed Russel bodies, macrophages, multinucleated giant cells, melanomacrophages (MMP), mast cells (MC) and Splendore–Hoepply material in the lesions.
Conclusion: Signet ring cells identified after vaccination have been hitherto described as svollen mast cells. This study shows that these cells fit the Russel body characteristic, consistent with humoral stimulation following vaccination and foreign material precipitate, Splendore-Hoepply material. MHC+ cells were located circumferal to granuloma centers. MMP were present containing melanosomes in different developmental stages. 相似文献
Methods: Fish suffering from severe reaction 6 to 9 months after vaccination were selected. We investigated granuloma from peritoneum, at the injection site. Morphological staining techniques, IHC to visualise MHC+ cells and ultrastructural analysis were performed.
Results: Microbial investigations revealed no infective agents. Histological and ultrastructural studies revealed Russel bodies, macrophages, multinucleated giant cells, melanomacrophages (MMP), mast cells (MC) and Splendore–Hoepply material in the lesions.
Conclusion: Signet ring cells identified after vaccination have been hitherto described as svollen mast cells. This study shows that these cells fit the Russel body characteristic, consistent with humoral stimulation following vaccination and foreign material precipitate, Splendore-Hoepply material. MHC+ cells were located circumferal to granuloma centers. MMP were present containing melanosomes in different developmental stages. 相似文献
824.
825.
Effects of background colour on growth performance,skin pigmentation,physiological condition and innate immune responses of goldfish,Carassius auratus 下载免费PDF全文
Khalil Eslamloo Sobhan R Akhavan Ahmad Eslamifar Morgane A Henry 《Aquaculture Research》2015,46(1):202-215
A study was carried out to investigate the effects of background colour on the growth performance, skin colour, haematology, physiological condition and non‐specific immune responses of goldfish, Carassius auratus. Goldfish were reared in tanks with four different background colours (white, black, blue and red) for 8 weeks. Fish growth performance markedly rose in white background compared with the other treatments. There was no significant difference in haematological parameters or plasma proteins concentrations between treatments. Plasma cortisol of fish reared in red background was significantly higher than that in black and white backgrounds. Plasma antiprotease and lysozyme activities were more than doubled in white and black treatments compared with the red and blue groups. The other immune parameters tested (plasma peroxidase, complement and bactericidal activities) did not significantly change between treatments. Skin carotenoid content and the intensity of fish skin colour extremely diminished in white background. This study revealed that red and blue backgrounds are chronically stressful and immunosuppressive in goldfish. White backgrounds will preferably be used for the culture of goldfish for best fish growth. However, a way to revert the colour loss of goldfish skin reared in white backgrounds remains to be investigated. 相似文献
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829.
New Forests - Wind is a common canopy disturbance in the upland oak (Quercus)- and hickory (Carya)-dominated stands of the Central Hardwood Region of the eastern US. Canopy openings range from... 相似文献
830.
The impact of a fungicide and an insecticide on soybean growth, yield, and profitability 总被引:1,自引:0,他引:1
A growing number of soybean producers have begun to incorporate below threshold fungicide and insecticide treatments into their management programs in attempts to increase yield. The objective of this study was to determine the influence of a fungicide and insecticide on soybean yield and growth when disease and insect pressure is minimal. Soybean was planted at three locations across Indiana, USA, in 2009 and 2010 and treated with various combinations of glyphosate, pyraclostrobin, and lambda-cyhalothrin. Yield was increased by 100 kg ha−1 and 150 kg ha−1 by a R4 application of pyraclostrobin alone and by lambda-cyhalothrin alone, respectively. Seed mass was increased 3% by pyraclostrobin, while seed number m−2 was increased 5% by lambda-cyhalothrin. No other yield component was influenced by the fungicide or insecticide. Economic analysis using Simulation and Econometrics to Analyze Risk (SIMETAR) demonstrated a single, post application of glyphosate to be the most efficient treatment option across a range of risk attitudes. This study indicates that yield increases are possible using below threshold applications of fungicides and insecticides. However, growers may not benefit from such applications if input costs are higher than the economic returns of the increased yield. 相似文献