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D. I. SMITH 《Addiction (Abingdon, England)》1988,83(2):219-222
Following the introduction of flexible hotel trading hours in Tasmania, hotels stayed open for approximately the same duration, but closed later than the previous 10.00 p.m. closing time. In the year after the legislative change there were 382 casualty accidents from 10.01 p.m. to 6.00 a.m., whereas the 95% confidence interval calculated on the basis of the previous five years was 309.3 to 356.3. By contrast, for the control time of 6.01 p.m. to 10.00 p.m. the 362 casualty accidents during the after period was within the 95% confidence interval of 331.1 to 365.3. With the later closing the accidents were significantly more likely to occur after midnight than before midnight. 相似文献
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The health promoting school: progress and future challenges in Welsh secondary schools 总被引:12,自引:2,他引:10
SMITH CHRISTOPHER; ROBERTS CHRIS; NUTBEAM DON; MACDONALD GORDON 《Health promotion international》1992,7(3):171-179
Data were obtained from a random sample of 87 secondary schoolsin Wales (UK) about the organization and provision of healtheducation teaching, the implementation of health related policies,and the involvement of outside agencies and professionals inthe planning and delivery of health education programmes. Theresults suggest that schools have made progress in curriculumdevelopment. However, if the concept of the health promotingschool is to be translated into practice, greater attentionwill need to be given us the development of broadly based policiesfor health covering both pupils and staff and the better integrationof school programmes with community resources. Greater understandingof the health promoting school concept by teaching staff andthe development of examples of good practice in embedding healtheducation into national curriculum subjects, are also advocated. 相似文献
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Electrical responses of the muscularis externa to distension of the isolated guinea-pig distal colon 总被引:8,自引:0,他引:8
T. K. SMITH R. A. BYWATER G. S. TAYLOR M. E. HOLMAN 《Neurogastroenterology and motility》1992,4(3):145-156
Abstract Enteric reflex pathways were studied in isolated segments of guinea-pig distal colon by recording the electrical responses to distension from the muscularis externa with suction electrodes. The end of the electrode wire were in the circular muscle and thus the recordings discussed below are deduced to be primarily from this layer. Moreover, intracellular microelectrodes in circular muscle cells and suction electrodes recorded similar events. Spontaneous activity consisted of myogenic slow waves at about 25 min -1 and transient biphasic potentials at about 6 min-1 and 3-sec duration which were dependent on a stimulus from the enteric nervous system as they were blocked by tetrodotoxin (0.5 μM), d-tubocurarine (30 μM) and hexa-methonium (100 μM). Atropine (0.8 μM) blocked the depolarizing part of the biphasic potentials and unmasked transient spontaneous inhibitory junction potentials (IJPs) (~2-sec duration) which appeared to be responsible for the hyperpolarizing part of the biphasic potential. Three different responses were observed at sites oral to distension of the colon: a transient depolarizing response that was cholinergic (blocked by atropine (0.8 μM); ascending cholinergic excitation) and, after atropine, a transient IJP (ascending inhibition) which was followed by a transient non-cholinergic depolarizaton (ascending non-cholinergic excitation) that was sometimes followed by several cycles of slow wave activity. The oral responses to anal distension were also blocked by the nicotinic antagonists and were similar to the neurogenic spontaneous events, which also appeared to originate from activity in ascending nervous pathways. Four different responses were observed following distension of the oral end of the segment: an IJP followed by a prolonged phase of hyperpolarization that lasted for the duration of the distension (descending inhibition); a burst of depolarizing potentials (for up to 30 sec) that followed the termination of distensions up to 25 sec and was blocked by atropine (0.8 μM) (delayed cholinergic excitation), and a transient non-cholinergic response that immediately followed the termination of distension (non-cholinergic ‘off’ response). Apamin (0.5 μM) reduced the amplitude of the spontaneous IJPs and evoked IJPs. After apamin, distension evoked a small transient hyperpolarization at oral sites, which was similar to spontaneous events, and the prolonged hyperpolarization at anal sites. A second distension given within 20 sec of the first evoked an IJP of reduced amplitude at oral sites in every preparation. In contrast, the amplitudes of the oral Cholinergic excitation and descending inhibition were relatively unaffected by reducing the interval between distensions. Thus distension stimulates excitatory and inhibitory motor neurons supplying the circular muscle both oral and anal to the stimulus. The polarity of the reflex relies in part on the differences in timing and duration of responses as well as the transmission characteristics of the nervous pathways. 相似文献
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