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Mechanics and Morphology of Silk Drawn from Anesthetized Spiders 总被引:1,自引:0,他引:1
CO2 and N2 anesthetized Nephila spiders produced dragline silk with mechanical properties that differed from control silk as a function of time under anesthesia.
Silk from CO2 spiders had a significantly lower breaking strain and breaking energy, significantly higher initial modulus, and marginally
lower breaking stress. At the onset of anesthesia the silk diameter became highly variable. During deep anesthesia silk either
became thinner or retained cross-section but fibrillated.
Received: 26 August 1999 / Accepted in revised form: 22 December 1999 相似文献
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Werner J. Kloft 《Die Naturwissenschaften》1989,76(4):149-155
The question whether the possibility exists of transmission of HIV by hematophagous insects from infected to uninfected persons is a point of very intensive discussion. The solution of this problem could help to explain the spreading of the disease in human populations and could contribute to an understanding of the evolution of AIDS and the possible transfer from wild primates into human populations. The classical routes of pathogen transmission by blood-sucking arthropods are either "mechanical" or "biological". Both ways are rejected, the latter since no replication of the retro-virus in the vector exists and its survival in the arthropod is very limited. Based on long experimental experience with biting flies as well as with plant-sucking insects a third hitherto neglected way of transmission by regurgitation of gut content can be introduced. Since regurgitation is neither "mechanical" nor "biological", "regurgitative transmission" must be introduced as an additional term. 相似文献
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Wir danken Dr. Kerndorff für die kritische Durchsicht des Manuskripts. 相似文献
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Gerald M. Slutzky 《Die Naturwissenschaften》1981,68(10):498-500
Parasite biochemistry is a field growing in parallel with the new surge of interest in tropical diseases. Whereas previously parasitologists have been required to adopt biochemical methodology in order to stay abreast of developments, today we find a new phenomenon: biochemists abandoning their classical systems (E. coli, red blood cells, etc.) to work on parasites. The 13th annual meeting of the Federation of European Biochemical Societies (FEBS) held in Jerusalem in August 1980 presented the perfect opportunity to summarize work done by parasite biochemists and to introduce this field to workers in classical biochemistry. 相似文献
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