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The aim of the study was to determine the effect of exogenous melatonin treatment on circulating prolactin levels in red deer. Melatonin was administered from 12 June 1984 (day 1) to lactating and non-lactating hinds in the feed daily at 1600 h, and to non-lactating hinds by a subcutaneous implant. Average concentrations (ng/ml) of prolactin in plasma taken serially over 15-h periods were significantly higher for untreated hinds than for melatonin-treated animals on day 15 whether lactating (66-133 v. 23-28, P less than 0.05) or non-lactating (28-174 v. 8-13, P less than 0.01), remained higher on day 36 (lactating: 41-152 v. 15-21, P less than 0.05; non-lactating: 21-50 v. 1-7, P less than 0.001) but had decreased to similar levels on day 72 (lactating: 5-24 v. 7-17; non-lactating: 2-9 v. 0-4). The advanced reduction in plasma prolactin for all melatonin-treated hinds was associated with an advanced onset of seasonal breeding activity.  相似文献   
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? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place.  相似文献   
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A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate.  相似文献   
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