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101.
As basic research for the effect of heavy oil on the fish immune system, in this study, the number of leukocyte was counted in Japanese flounder Paralichthys olivaceus, after exposure to heavy oil at a concentration of 30 g/8L for 3 days. To compare the numbers of bacteria in the skin mucus between oil-exposed and control fish, viable bacteria were enumerated by counting colony forming unit (CFU). Compared with 5.79+/-1.88 x 10(7)leukocytes/mL in the controls, the exposed fish demonstrated higher counts, averaging 1.45+/-0.45 x 10(8)cells/mL. The bacterial numbers of control fish were 4.27+/-3.68 x 10(4)CFU/g, whereas they were 4.58+/-1.63 x 10(5)CFU/g in the exposed fish. The results suggest that immune suppression of the fish occurred due to heavy oil stressor, and bacteria could invade in the mucus, resulting in the increasing leukocyte number to prevent infectious disease.  相似文献   
102.
Lalou  C 周立君 《世界地质》1999,18(3):49-54
通常认为,构造变形是热传递对流和热液循环以及伴生矿床产出的必要条件。迄今为止,对海底热液成矿作用的勘探调查还主要集中于太平洋和大西洋的扩张洋脊附近,而对扩张速度缓慢的印度洋海脊的调查不多。直到1987年,印度洋上除少数低温热液矿床以外,还没有发现高温热液成矿作用指示。在GEMINOⅢ航次中,利用深拖照相机在Rodriguez三图1 研究区位置联点北部首次发现了高温成矿作用指示。为了确定和研究目前及过去印度洋中脊的热液活动情况,已经进行了多个航次,最后两个航次主要对Rodriguez三联点北部的印…  相似文献   
103.
基于了解中国早期期刊(1815-1930年)的发展历史,通过回顾和分析那些有影响的期刊,总结出中国早期期刊发展的6点特征,以期对现代办刊人有所启示.  相似文献   
104.
The corals of the Persian/Arabian Gulf are better adapted to temperature fluctuations than elsewhere in the Indo-Pacific. The Gulf is an extreme marine environment displaying the highest known summer water temperatures for any reef area. The small and shallow sea can be considered a good analogue to future conditions for the rest of the world’s oceans under global warming. The fact that corals can persist in such a demanding environment indicates that they have been able to acclimatize and selectively adapt to elevated temperature. The implication being that colonies elsewhere may be able to follow suit. This in turn provides hope that corals may, given sufficient time, similarly adapt to survive even in an impoverished form, under conditions of acidification-driven lowering of CaCO3 saturation state, a further consequence of raised atmospheric CO2. This paper demonstrates, however, that the uniquely adapted corals of the Gulf may, within the next three centuries, be threatened by a chronic habitat shortage brought about by the dissolution of the lithified seabed on which they rely for colonisation. This will occur due to modifications in the chemical composition of the Gulf waters due to climate change.  相似文献   
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