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《Journal of Natural History》2012,46(18):1431-1442
Predator‐induced defence responses have been reported in 15 species of ciliates representing three subclasses: Hypotrichia, Stichotrichia and Hymenostomia. However, the discovery of this phenomenon in such distantly related groups suggests that it could be more widespread within the Ciliophora. In laboratory experiments, we tested 23 potential prey species with a range of potential predators including other ciliates (12 spp.), amoebae (two spp.), rotifers (two spp.), a turbellarian worm (Stenostomum sphagnetorum), and an oligochaete worm (Chaetogaster sp.). In each experiment, one predator species was incubated for 24?h with one potential prey species and the latter was examined for evidence of a defence response. One new example of predator‐induced morphological change was recorded (Euplotes viridis) and detailed observations were made for one poorly known example (E. eurystomus). Both species significantly increased their width (by about 35% and 23%, respectively) in the presence of the turbellarian worm S. sphagnetorum. An induced life cycle change was recorded for the first time among hypotrichs with E. muscorum exhibiting significantly increased rates of encystation in the presence of the ciliate predators Dileptus anser and Spathidium sp. Finally, Euplotes patella, Euplotes sp. and Stylonychia pustulata, which are usually regarded as omnivorous rather than predatory ciliates, all induced morphological change in Colpidium kleini, the C. kleini cells becoming significantly shorter and wider. No examples of induced defence response were found among groups other than hypotrichs and hymenostomes. 相似文献
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陈国平 《西南科技大学学报》2001,16(4):44-46
基于现有的多弹头导弹技术,通过质心运动定理分析导弹防御系统NMD的防御能力,从而得出结论导弹防御系统NMD的防御能力是非常有限的. 相似文献
14.
防空C3I系统综合集成仿真环境研究 总被引:2,自引:0,他引:2
防空C3 I系统综合集成仿真环境的研究 ,是降低防空C3 I系统仿真复杂性、提高仿真全过程透明度以及系统重用性的根本途径。根据防空C3 I系统仿真的特点 ,探讨了防空C3 I系统综合集成仿真环境的概念框架 ,并针对其综合集成仿真环境的体系结构和仿真支撑环境等关键技术进行了深入的分析 ,提出了构建防空C3 I系统综合集成仿真环境的基本框架。 相似文献
15.
Scavenger receptor family proteins: roles for atherosclerosis, host defence and disorders of the central nervous system 总被引:11,自引:1,他引:10
Y. Yamada T. Doi T. Hamakubo T. Kodama 《Cellular and molecular life sciences : CMLS》1998,54(7):628-640
In this review, we summarize the structure and function of the scavenger receptor family of proteins including class A (type
I and II macrophage scavenger receptors, MARCO), class B (CD36, scavenger receptor class BI), mucinlike (CD68/macrosialin,
dSR-CI) and endothelial (LOX-1) receptors. Two motifs have been identified as ligand-binding domains a charged collagen structure
of type I and II receptors, and an immunodominant domain of CD36. These structures can recognize a wide range of negatively
charged macromolecules, including oxidized low-density lipoproteins, damaged or apoptotic cells, and pathogenic microorganisms.
After binding, these ligands can be either internalized by endocytosis or phagocytosis, or remain at the cell surface and
mediate adhesion or lipid transfer through caveolae. Under physiological conditions, scavenger receptors serve to scavenge
or clean up cellular debris and other related materials, and they play a role in host defence. In pathological states, they
mediate the recruitment, activation and transformation of macrophages and other cells which may be related to the development
of atherosclerosis and to disorders caused by the accumulation of denatured materials, such as Alzheimer's disease.
Received 17 September 1997; received after revision 16 March 1998; accepted 17 March 1998 相似文献
16.
蒋林华 《安庆师范学院学报(自然科学版)》2002,8(3):13-16
在21世纪中华武术逐渐走向世界,我国全民健身体育不断发展的形势下,着重分析了在太极拳技击运动中的力学原理,阐述了太极拳技击运动中的用力都是受着运动定律的支配,使太极拳的技击运动的技术动作更趋规范化. 相似文献
17.
战略导弹突防仿真模型 总被引:3,自引:1,他引:2
汪民乐 《系统工程与电子技术》1996,(10)
本文提出了战略导弹突防仿真模型,在此基础上建立了导弹突防模拟系统并在微机上实现运行。该系统可为战略导弹作战提供决策支持,也可为研究导弹突防提供实验手段。运用所建立的仿真模型,本文进行了模拟运行,得到了一些有益的结果,另外对改变模型参数结果将怎样变化,也作了探索。本文的结果将有助于导弹武器系统的研制、论证及使用。 相似文献
18.
该文基于野战防空C ̄3I系统战前决策的内容,提出了一种统一的战前辅助决策的MADM模型;并讨论了它在实际问题中的应用. 相似文献
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