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S Farrah C Wallis P T Shaffer J L Melnick 《Applied and environmental microbiology》1976,32(5):653-658
Virus can be adsorbed from effluents of sewage treatment plants on large-surface membranes. Subsequent elution of virus requires large volumes, which in turn requires reconcentration of virus for assay. However, reconcentration of such viral eluates on small adsorbent surfaces is difficult because certain soluble sewage components are adsorbed along with the virus on the initial virus adsorbent and are removed along with the virus by the eluent. Upon acidification of the initial eluate to reconcentrate the virus on smaller membrane surfaces, flocs are formed that interfere with the reconcentration process. To circumvent this problem, the interfering sewage components can be removed by activated carbon and ion-exchange resins. The virus is then readily reconcentrated on small membranes. 相似文献
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Janette Wallis Barbara J. King Christian Roth-Meyer 《Primates; journal of primatology》1986,27(1):83-94
Twelve adult female crab-eating monkeys (Macaca fascicularis) were placed in six pairs of adjacent cages, allowing physical contact between members of these experimental pairs. Twelve
additional females remained singly caged (no physical contact allowed) and served as six control “pairs.” In both experimental
and control pairs, one member had a history of regular menstrual cycles, whereas the other tended to have cycles that were
unusually long and/or irregular. Over a six-month period, menses and amount of vaginal secretion were recorded daily for all
subjects, and the behavior of experimental pairs was sampled three times per week. During the course of the study, the irregular
experimental subjects began to exhibit menstrual cycles of near normal length although there was no apparent trend to synchronize
cycles. Irregular controls continued to show cycles that were abnormally long. Vaginal secretions tended to increase in all
regularly cycling animals during days 9–15 (peak day 11) or reverse days 21–16 of the cycle, consistent with the estimated
time of ovulation. Analysis of behavior indicated that irregularly cycling subjects inspected the genitalia of their regularly
cycling cagemates at a significantly higher frequency than the converse (F=12.61,p<.005), particularly during the follicular phase (F=3.39,p<.07). These results suggest that close physical contact may serve to transmit chemical and/or hormonal cues that can normalize
the menstrual cycle of crab-eating monkeys. 相似文献