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1.
J Y Paterson C A Bedford F A Harrison R B Heap 《Journal of reproduction and fertility》1976,46(2):313-322
The rates of metabolism of progesterone and 20alpha-dihydroprogesterone (20alpha-diHP) in sheep have been measured during and after the infusion of tracer amounts of [3H]progesterone. There were significant differences in the blood concentration of [3H]progesterone between experiments, but these were not attributable to the stage of gestation or to the difference between pregnant and non-pregnant animals. The mean (+/- S.E.M.) metabolic clearance rate of progesterone was 3-277 +/- 0-239 litres blood/min. The simplest model of the distribution of progesterone was one containing two pools, V1[P] and V2[P], where [p] is the blood concentration of progesterone, and in 23 experiments on 7 sheep the mean pool dimensions were 7-8[P] mug and 70[P] mug, respectively. This model was developed to include the formation of 20alpha-diHP from progesterone. Progesterone appeared to be the major source of 20alpha-diHP, though this did not seem to be an obligatory metabolite. The parameters obtained gave comparably low residual deviations for both labelled steroids and were consistent with other observations made on progesterone clearance. 相似文献
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Catherine Hofer Levison Donald W. Hastings Jerry N. Harrison 《American journal of physical anthropology》1981,56(1):83-93
Census reports and information in burial records of Manti, Utah from 1849 to July 1977 are examined in order to (1)document mortality trends and differentials by age, sex, cause-of-death, and seasonality as Manti passed from a frontier settlement to a rural agricultural community; and (2) ascertain whether the shifts in the cause-of-death structure follow those patterns outlined by Omran (1971, 1974, 1977) in his theory of the epidemiologic transition. Findings parallel patterns suggested by Omran. Major factors accounting for mortality reductions are (1) elimination of the population's dependence upon a contaminated water supply, and (2) adoption of medical advances as they became available. 相似文献
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A comparative study using either glycerol or an egg yolk-citrate-glycerol mix for cryoprotection under the conditions described showed the latter to give a significantly better post-thaw motility. The greatest drop was noted within the first hour, suggesting that freezability of a sample could be judged accurately by rethawing at that time.Controlled studies using scanning electron microscopy clearly showed a greater head disruption after freezing with glycerol and looped tails after centrifugation, which could account for some of the findings of the first part of the study.These findings are reviewed and it is recommended that seminal samples are not centrifuged and that a complex medium be employed for seminal freezing and storing. 相似文献
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Edward Harrison 《BMJ (Clinical research ed.)》1916,1(2888):645-647
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Of 106 patients admitted for investigation to a neurological hospital with a presumptive diagnosis of dementia, 84 were confirmed to have intellectual impairment or loss of learning and memory function or both. A possible aetiology for the dementia was found in 36 of these 84 patients; the commonest causes discovered were intracranial mass lesions, arterial disease, and alcoholism. Fifteen of the 106 patients were found not to be demented but to have some other illness, most commonly depression. Of the whole series some 15% of the patients suffered from conditions that were amenable to treatment. 相似文献