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TM Moran E Toy Y Kuzu H Kuzu H Isobe JL Schulman 《Canadian Metallurgical Quarterly》1995,155(2):759-765
Cell-mediated immunity is a crucial part of recovery from virus infections. Adoptive transfer of T cells into infected animals is restricted by the need for Ag-specific and MHC-restricted T cells. One way to overcome these limitations is to use bifunctional Abs to redirect the T cells against virus-infected cells. We have demonstrated that bifunctional Abs can inhibit virus replication in the presence of activated T cells. To generate a large number of activated T cells in a short time, we tested the ability of the superantigen, staphylococcal enterotoxin B (SEB), to activate T cells. We demonstrate that SEB-activated T cells are effective killers when bridged to Fc receptor-bearing target cells using anti-CD3 Abs. SEB T cells can lyse virus-infected target cells in the presence of HHA6, a bifunctional Ab specific for the V beta 8 TCR product and the H1 hemagglutinin of influenza A/PR/8/34 virus. In addition, bifunctional Ab and SEB T cells can inhibit multicycle virus replication in vitro. In a conventional 4-h chromium release assay, SEB-activated CD8 T cells are efficient killers, whereas CD4 T cells are not. Yet both subpopulations have the ability to inhibit multicycle replication in vitro. Superantigens may represent a potent method for generation of effector cells for use in redirected immunotherapy protocols. 相似文献
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本文根据石宝露天铁矿的实际地质情况及其边坡目前已经产生的一些不良状况,对影响边坡稳定性的诸多因素进行全面的分析,并采用极限平衡法中的Bishop法对该矿的边坡稳定性进行分析计算,通过计算得到的安全系数来判断该边坡是否稳定,并提出一些合理的整改及加固措施,为石宝铁矿的安全生产提供科学依据。 相似文献
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In many parts of the world, mine production and expansion are increasingly limited by access to water. One solution is to
consider a water market that would allow trading of mine site water (worked water) from wetter mines to drier mines. However,
there is currently no policy support for such a market and it is likely that without government support via incentives, mines
will continue to favour freshwater use because it is relatively inexpensive. Furthermore, mines have a high capacity to pay
for the water they use, and freshwater creates few risks for production. The opportunity provided by water savings within
a trading scheme could be viewed as a source of money to provide incentives for the transfer of worked water between mines.
In this paper, we present a new method to trade water among mines based on a site water balance assessment utilising historical
climate data, and apply this method to a demonstration region containing multiple coal mines. On average, 340 ML could be
transferred per year to drier mines but there remains 11,440 ML per year of water demand unable to be met by trading. The
direct monetary value of the worked water that could be transferred, derived from additional coal mining, would be significant.
Irrigation may be an attractive option if available infrastructure can be used to trade the saved fresh water in existing
markets, thereby providing indirect monetary value (i.e. external to coal production). Alternative uses of water savings may
have considerable additional non-monetary value that directly affects the mining industry’s social license-to-operate and
its security of long term water supply. 相似文献
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Sivasegaran K Ho L Moran KL Bantseev V Sivak JG 《International journal of cosmetic science》2007,29(2):103-110
Pre-screening of cosmetic ingredients is vital for consumer safety. Previous in vivo techniques, such as the Draize test, have proved to be unreliable in predicting ocular irritancy and therefore there is a need for alternate testing methodologies. One such test is the scanning laser in vitro assay system which quantifies irritancy based on the focusing ability of the cultured bovine lens. In combination with confocal microscopy, a more thorough documentation of ocular irritancy can be achieved. This study investigates the response of cultured bovine lenses over time to butyl, methyl and propyl parabens, which are common antimicrobial agents found in cosmetic and ophthalmic products. The focusing ability of the lens was measured with an automated laser scanner over a period of 96 h. At 120 h post-treatment, the lenses were analysed by using a confocal laser scanning microscope to determine the characteristics of nuclei, and the morphology and distribution of mitochondria within the lenses. Irritancy to the three parabens was investigated at both an optical and cellular level. Each of the parabens was tested at 0.002% and 0.2%, where the 0.2% butyl paraben was found to be the most irritating. 相似文献
90.