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The aim of the present study was to explore the perspectives of patients receiving treatment for colorectal cancer and compare priorities and attitudes in rural and urban areas.

The plateau‐like depolarizing potentials evoked in Purkinje cell dendrites by impulses in climbing fibres (Ekerot & Oscarsson, 1981) were conditioned by single parallel fibre volleys and investigated by intra‐ and extracellular recording from cat cerebellar cortex. The conditioning parallel fibre volleys evoked predominantly inhibitory potentials of long duration in the Purkinje cell dendrites. Massive parallel fibre volleys, which may evoke plateau‐like depolarizing potentials (Campbell, Ekerot, Hesslow & Oscarsson, 1983) were avoided. In proximal dendrites parallel fibre volleys preceding climbing fibre responses reduced or abolished the plateau potential, whereas the initial spike‐like component of the climbing fibre responses was largely unaffected. Parallel fibre stimulation during already established plateau potentials immediately terminated the plateaus. In distal dendrites parallel fibre stimulation preceding climbing fibre responses reduced or abolished both the plateau potential and the initial component of the climbing fibre responses. Parallel fibre stimulation during established plateau potentials did not immediately terminate the plateau potentials but reduced their duration. The results of the present investigation suggest that single dendritic branches of Purkinje cells serve as independent integrators of mossy fibre and climbing fibre inputs.

Responses evoked in Purkinje cell dendrites by parallel fibre volleys and climbing fibre impulses were investigated by intra‐ and extracellular recording from cat cerebellar cortex. The depth distribution of recording sites suggested that the intracellular recordings were predominantly from proximal dendrites whereas the extracellular recordings were predominantly from distal dendrites. Parallel fibre stimulation evoked monosynaptic excitation and disynaptic inhibition in the dendrites and, at higher strength, prolonged plateau‐like responses in distal dendrites but only rarely in proximal dendrites. However, when the inhibitory synapses were blocked with topically applied picrotoxin, parallel fibre volleys evoked plateau potentials also in proximal dendrites. The duration of the parallel‐fibre‐evoked plateau potentials in distal dendrites was prolonged by increasing the intensity of the eliciting stimulus or by increasing the number of stimuli. A similar prolongation in the duration of climbing‐fibre‐evoked plateau potentials was observed when brief repetitive stimulation was applied to the inferior olive. The investigation provided evidence that under physiological conditions plateau potentials in Purkinje cell dendrites are exclusively evoked by climbing fibre impulses.

Extracellularly recorded climbing fibre responses in Purkinje cell somata in the cerebellar cortex were investigated in cats deeply anaesthetized with barbiturate. The effects on the amplitude of initial and secondary spikes of preceding climbing fibre activation, on‐beam parallel fibre activation and off‐beam parallel fibre activation were studied. When a climbing fibre response was preceded by climbing fibre activation there was a decrease in the amplitude of the initial spike of the second response at intervals up to 25 ms and little effect at longer intervals. Secondary spike amplitude was greatly increased at intervals up to 100 ms. When a complex spike was preceded by on‐beam parallel fibre activation there was a decrease in the initial spike amplitude at short intervals and an increase in the amplitude at long intervals. Secondary spike amplitude was increased up to 150 ms after an on‐beam parallel fibre volley. When a complex spike was preceded by off‐beam parallel fibre stimulation there was an increase in initial spike amplitude at intervals up to about 200 ms and a decrease in secondary spike amplitude at intervals up to about 150 ms. The results show that the amplitude of the secondary spikes can be modified by a preceding input to the Purkinje cell. The results also suggest that the secondary spikes are generated in the Purkinje cell dendrites and the initial spike in the soma.

Responses evoked in Purkinje cells by climbing fibre activity were investigated by recording from Purkinje cell axons in the cerebellum of anaesthetized cats. Purkinje cell axons were identified by firing pattern and by latency of responses to stimulation of peripheral nerve and of the inferior olive. Axonal climbing fibre responses usually consisted of one to two spikes, suggesting that normally only the initial spike or, at most, this and one of the secondary spikes are propagated down the Purkinje cell axon. When two successive climbing fibre responses were evoked, the number of spikes in the second response was increased, usually up to three to five. This effect could be obtained at stimulation intervals of up to 100 ms. In a few cases it was possible for a climbing fibre response to be preceded by a parallel fibre volley evoked by stimulation of the cerebellar surface. This increased the number of spikes in the axonal climbing fibre response. The results suggest that the number of propagated spikes in the climbing fibre response can be modified by a preceding input to the Purkinje cell.

OBJECTIVE: To determine secondary preventive treatment and habits among patients with coronary heart disease in general practice. DESIGN: Process of care data on a random sample of patients were collected from medical records. Health and lifestyle data were collected by postal questionnaire (response rate 71%). SETTING: Stratified, random sample of general practices in Grampian. SUBJECTS: 1921 patients aged under 80 years with coronary heart disease identified from pre-existing registers of coronary heart disease and nitrate prescriptions. MAIN OUTCOME MEASURES: Treatment with aspirin, beta blockers, and angiotensin converting enzyme inhibitors. Management of lipid concentrations and hypertension according to local guidelines. Dietary habits (dietary instrument for nutritional evaluation score), physical activity (health practice indices), smoking, and body mass index. RESULTS: 825/1319 (63%) patients took aspirin. Of 414 patients with recent myocardial infarction, 131 (32%) took beta blockers, and of 257 with heart failure, 102 (40%) took angiotensin converting enzyme inhibitors. Blood pressure was managed according to current guidelines for 1566 (82%) patients but lipid concentrations for only 133 (17%). 673 of 1327 patients (51%) took little or no exercise, 245 of 1333 (18%) were current smokers, 808 of 1264 (64%) were overweight, and 627 of 1213 (52%) ate more fat than recommended. CONCLUSION: In terms of secondary prevention, half of patients had at least two aspects of their medical management that were suboptimal and nearly two thirds had at least two aspects of their health behaviour that would benefit from change. There seems to be considerable potential to increase secondary prevention of coronary heart disease in general practice.

OBJECTIVE: To evaluate the effects of secondary prevention clinics run by nurses in general practice on the health of patients with coronary heart disease. DESIGN: Randomised controlled trial of clinics over one year with assessment by self completed postal questionnaires and audit of medical records at the start and end of the trial. SETTING: Random sample of 19 general practices in northeast Scotland. SUBJECTS: 1173 patients (685 men and 488 women) under 80 years with working diagnoses of coronary heart disease who did not have terminal illness or dementia and were not housebound. INTERVENTION: Clinic staff promoted medical and lifestyle aspects of secondary prevention and offered regular follow up. MAIN OUTCOME MEASURES: Health status measured by the SF-36 questionnaire, chest pain by the angina type specification, and anxiety and depression by the hospital anxiety and depression scale. Use of health services before and during the study. RESULTS: There were significant improvements in six of eight health status domains (all functioning scales, pain, and general health) among patients attending the clinic. Role limitations attributed to physical problems improved most (adjusted difference 8.52, 95% confidence interval 4.16 to 12. 9). Fewer patients reported worsening chest pain (odds ratio 0.59, 95% confidence interval 0.37 to 0.94). There were no significant effects on anxiety or depression. Fewer intervention group patients required hospital admissions (0.64, 0.48 to 0.86), but general practitioner consultation rates did not alter. CONCLUSIONS: Within their first year secondary prevention clinics improved patients' health and reduced hospital admissions.