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51.
Raymond Wootton 《FEBS letters》1984,178(2):187-192
In a recent communication Lehninger and co-workers (Costa, L.E., Reynaferje, B., and Lehninger, A.L. (1984) J. Biol. Chem. 259, 4802-4811) reported values approaching 8 for the H+/O ratio of vectorial proton ejection from rat liver mitochondria respiring with succinate. Here we present a rigorous analysis of these measurements which reveals that they may significantly overestimate the true H+/O stoicheiometry.  相似文献   
52.
Blood chemistry values were collected over a three-year period from at least 10 colony-born and 24 wild-born apparently normal common marmosets. BUN, SGOT, creatinine, calcium, phosphorus, alkaline phosphatase, protein, albumin, cholesterol, triglycerides, uric and glucose values were determined. A statistical comparison of baseline values was made between wild-born, colony-born, male and female marmosets. Also the same comparison was made between common marmosets and cotton-top tamarins, white lipped tamarins and human subjects.  相似文献   
53.
Résumé Les performances de pièges à Tabanidae de type Manitoba ont été étudiées en milieu montagnard et subalpin. On a testé les influences respectives de la présence ou de l'absence d'une source de CO2, de la nature de cette source (solide ou gazeuse), de la présence ou de l'absence d'un leurre visuel (sphère noir brillant), de la nature transparente ou opaque de la partie supérieure du piège (hotte conique). Plus de 8.000 Tabanidae et plus de 51.000 Muscidae ont été pris au cours de ces essais totalisant 660 heures-pièges.
Summary Manitoba traps, traps without decoy or with black canopy, unbaited or baited with dry ice or compressed carbon dioxide, were compared for the numbers of horse flies and muscid flies caught in mountainous mixed wood and pasture land and in subalpine larch forest between 1500 m and 2200 m, in July. More muscid flies were captured in the compressed CO2 baited traps than in dry ice baited traps. Haematopota pluvialis, Tabanus maculicornis and Tabanus quatuornotatus were more attracted by CO2 than Tabanus bromius. T. bromius was more attracted by the decoy than other species. The genus Atylotus and T. bromius are more attracted to the black canopy than other species. The visual decoy is more necessary to the efficiency of the trap than the chemical bait. The CO2 baited Manitoba trap caught the greatest number of horse flies (180 per trap and per hour). The unbaited Manitoba trap was efficient too, but other traps were inefficient. About 8000 horse flies and 51000 muscid flies were caught.
  相似文献   
54.
The incidence of caries and abscesses in 246 archeologically derived skeletal specimens from the Ipiutak and Tigara levels at Point Hope, Alaska, and 79 specimens excavated from Jones Point, Kodiak Island, Alaska were investigated. All three collections span long periods of time. Only pre-white contact specimens were used. Each specimens was sexed and aged in five year groupings, using standard techniques. Caries and abscesses were recorded by type and degree of severity and correlated with age, sex, and site of origin. All samples displayed very low caries rates and few abscesses per tooth and per individual (both observed frequencies, and frequencies corrected for postmortem loss of teeth). DMF scores were tabulated using both observed and corrected frequencies. Very heavy occlusal wear in all three samples could account for the majority of abscesses and pulp exposures, while the low caries rates are attributable to traditional diets totally devoid of refined sugars, starches, and food additives.  相似文献   
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Some novel studies of the properties of the antimony microelectrode used for intracellular pH measurements are described. First, it is shown that currents in the picoampere range, such as those encountered as leakage in some electrometers, induce important changes in pH sensitivity. The response time of the electrode has also been measured and indicates that the electrode exhibits a rapid time course which would be very useful for dynamic cytoplasmic pH investigations. An example of internal pH recording during cellular acidification in Xenopus laevis oocyte is also presented.  相似文献   
59.
Two large groups of prehistoric Eskimo skeletons from Point Hope, Alaska, were evaluated for dental wear and several measures of periodontal disease. Occlusal attrition was found to increase steadily with increasing age. Crown height decreased proportionately. Assessing periodontal disease by inspecting apparent alveolar recession was judged ineffective due to possible supereruption. Infrabony pockets, the result of severe localized periodontal disease indicated that in Ipiutak people between the ages of 25 and 30, and Tigara people between 35 and 40, more dental sites were affected by periodontal disease than were not. This suggests a cultural, genetic, or dietary difference between the two groups. Male/female differences were slight in all parameters studied.  相似文献   
60.
李贵山  梁妮 《蛇志》1991,3(4):4-5
本文选用金黄地鼠的微血管,利用显微高速摄影技术,放大微观流场和血细胞,连续地“冻结”短瞬间的变化状态,把物理图象呈现在胶片上,经图像分析和数据处理,从定性及定量方面研究血液微流变学,为生命科学和医学研究提供了又一种新的方法。  相似文献   
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