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This paper presents experimental data on : (1) the natural emission of microwave radiation by biological systems, and (2) the effect of drugs as well as microwave radiation on specimen microwave emission. Experiments were conducted on guinea pigs, mice, rabbits, and human subjects. The results were obtained with two different radiometers, one of the correlation type and one of the Dicke type, operating in the X-band at about 9 GHz with a sensitivity of approximately 0.1 degrees K. The results demonstrate the feasibility of this technique and suggestions are made for its use in bilogy, medicine, and in the field of biocommunications. 相似文献
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Watts FZ Hoffmann E 《BioEssays : news and reviews in molecular, cellular and developmental biology》2011,33(7):529-537
Recent discoveries have identified the small ubiquitin-like modifier (SUMO) as the potential 'missing link' that could explain how the synaptonemal complex (SC) is formed during meiosis. The SC is important for a variety of chromosome interactions during meiosis and appears ladder-like. It is formed when 'axes' of the two homologous chromosomes become connected by the deposition of transverse filaments, forming the steps of the ladder. Although several components of axial and transverse elements have been identified, how the two are connected to form the SC has remained an enigma. Recent discoveries suggest that SUMO modification underlies protein-protein interactions within the SC of budding yeast. The versatility of SUMO in regulating protein-protein interactions adds an exciting new dimension to our understanding of the SC and suggests that SCs are not homogenous structures throughout the nucleus. We propose that this heterogeneity may allow differential regulation of chromosome structure and function. 相似文献
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Kevin?B.?PottsEmail author David?P.?Watts Richard?W.?Wrangham 《International journal of primatology》2011,32(3):669-690
Several recent studies have documented considerable intraspecific and intrapopulation ecological variation in primates. However,
we generally lack an understanding of how such variability may be linked to concomitant demographic variation among groups
or populations of the same species, particularly in regard to large-bodied and wide-ranging species with high ecological flexibility,
such as chimpanzees (Pan troglodytes). We compared the feeding ecology of chimpanzees inhabiting 2 sites in Kibale National Park, Uganda that differ 3-fold in
chimpanzee density and support notably different plant communities. Chimpanzees at Ngogo, a site with the largest known chimpanzee
community and unusually high chimpanzee density, spent a significantly lower percentage of time resting (and pregnant and
lactating females spent more time feeding), incorporated higher percentages of ripe fruit in their diet, had lower dietary
diversity values, and had shorter and less variable average patch residency times than did their counterparts at the nearby
Kanyawara site, which supports a relatively low density of chimpanzees. In addition, feeding party size was significantly
and positively related to feeding patch size at Ngogo, but not at Kanyawara. Together these findings aid in explaining the
noted disparity in chimpanzee community size and density between Ngogo and Kanyawara by suggesting that the diet of Ngogo
chimpanzees is of higher overall quality than that of Kanyawara chimpanzees. They also highlight the potentially profound
influence of even small-scale habitat heterogeneity on the ecology of primates. Researchers must take such influences into
account when attempting to draw conclusions about species- or population-level characteristics. 相似文献