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This study compares health status, demographic and socioeconomic characteristics of users and non-users of NHS Direct in order to establish whether the service is being used by people with the greatest need for healthcare services. It suggests that use of NHS Direct is widespread among carers of children under 5 years old, but there is evidence that it may not be accessed equitably by those from ethnic minorities, lower socioeconomic groups and those with established ill health.  相似文献   
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BACKGROUND: To investigate vergence adaptation during the incipient phase of presbyopia, when the amplitude of accommodation approaches the level where the first reading addition is required. The study aimed to assess the ability of the vergence system to counteract changes in the component contributions to the overall vergence response with the decline in the amplitude of accommodation in presbyopia, although previous reports on the nature of changes in accommodative, tonic and proximal vergence are equivocal. METHODS: Using a 'flashed' Maddox rod technique, an assessment of vergence adaptation to 6delta base-out and 6delta base-in prism was made for 28 subjects (aged 35-45 years at the commencement of the study). The measurements were taken four times over a 2-year period. RESULTS: Using a repeated measures analysis of variance, the results show that with the decline in amplitude of accommodation, there is a statistically significant reduction in the magnitude of vergence adaptation to both base-out (p < 0.05) and base-in prism (p < 0.01). CONCLUSIONS: This study shows that with ageing, there is a decrease in the ability of the slow vergence mechanism to overcome a change in fusional vergence demand and would suggest that either the fast component of fusional vergence must cope with any change in fusional vergence demand or that the sum of the accommodative, tonic and proximal vergence responses are virtually stable with age.  相似文献   
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The purpose of this study was to examine the effect of first metatarsophalangeal arthrodesis on the sagittal plane orientation of the first ray and the medial longitudinal arch. Lateral weightbearing radiographs of 48 patients (54 feet) having undergone the procedure were retrospectively reviewed. Patients were separated into three groups based on their preoperative diagnosis: hallux rigidus, hallux valgus, or rheumatoid forefoot deformity. First metatarsal declination, talometatarsal, talar declination, calcaneal inclination, and talocalcaneal angles were measured on pre- and postoperative radiographs. Multivariate analysis of variance determined that there was a significant postoperative change (p < .001) in angular measurements, particularly in the first metatarsal declination, talometatarsal, and talocalcaneal angles. There was also a significant difference (p < .01) in the angular measurements between the hallux rigidus group and the other two groups. However, the amount of change from pre- to postoperatively did not vary significantly between the groups. A calculation of Pearson correlation coefficients found no significant correlation between the hallux dorsiflexion angle and changes in angular measurements. The radiographic changes found in this study support Hicks' windlass model: fixed dorsiflexion of the hallux causes plantarflexion of the first ray and an increase in the medial longitudinal arch.  相似文献   
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Stimulation of the nasal mucosa produces a number of respiratory reflexes the afferent limb of which is provided by the ethmoidal nerve, a branch of the trigeminal nerve. In the cat this nerve terminates within the trigeminal nucleus. It has no direct projection to brainstem respiratory centres. This study examines the response of respiratory-related neurones in the nucleus of the solitary tract (NTS) to ethmoidal stimulation. It demonstrates that these neurones show both excitatory and inhibitory responses to ethmoidal stimulation. Thus, the NTS appears to be involved in respiratory reflexes initiated by stimulation of the nasal mucosa.  相似文献   
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Ebstein's anomaly is the most significant congenital anomaly involving the tricuspid valve. This lesion may present in a simple form or may be complicated by other lesions. Patients with this anomaly may vary from mildly symptomatic to severely debilitated. The role of surgical treatment is not uniformly agreed upon, and the optimal procedure for correction or palliation is not clearly defined. Because of the wide spectrum of morphologic abnormalities which may be present in Ebstein's anomaly, no one particular operation may always be satisfactory. We and other groups continue to search for optimal procedures and feel strongly that individualization must be carried out to optimize the result in each patient. We encountered a patient with Ebstein's anomaly in an almost atretic tricuspid valve. In addition, there was severe right ventricular outflow tract obstruction and pulmonary valve stenosis. In this patient the "Fontan Principle" was successfully applied in his management.  相似文献   
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