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21.
Hypertension and tachycardia are well known features of acute porphyria and have been shown to be related to increased circulating catecholamines. The mechanism by which circulating catecholamines are increased was studied using the isolated perfused rat heart and human platelets as a model of adrenergic neuronal function. It was found that neither delta-aminolevulinate (ALA) nor porphobilinogen (PBG) blocked uptake or caused release in the isolated perfused rat heart. Platelets from six patients with acute prophyria, three in remission and three latent, with matching normal controls were studied with regard to their uptake of [(3)H]norepinephrine in the presence of ALA or PBG. It was found that ALA and PBG significantly reduced uptake and accumulation of [(3)H]-norepinephrine in patients with acute porphyria; however, no similar reduction in uptake and accumulation was observed in the platelets of normal controls. Therefore, it appears that there is a latent defect in the catecholamine uptake and (or) accumulation of platelets of patients with acute prophyria which only manifests itself in the presence of ALA or PBG. If platelet uptake serves as a model of adrenergic neuron uptake, this suggests that elevated circulating catecholamine levels during acute attacks of acute porphyria are caused at least partially by blockade of re-uptake into the sympathetic neurons. 相似文献
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Five newborn infants who developed subaponeurotic haemorrhage are described. Three infants were delivered by vacuum extraction, and 3 infants died. The importance of early diagnosis and prompt treatment is emphasized. 相似文献
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E Bennett-Guerrero L Ayuso C Hamilton-Davies WD White GR Barclay PK Smith SA King LH Muhlbaier MF Newman MG Mythen 《Canadian Metallurgical Quarterly》1997,277(8):646-650
This study assesses the reliability of a self-reported health questionnaire completed by 413 subjects aged 25-74 yr in the Erie County Periodontal Disease (ECPD) Study. Specific questions on general and oral health conditions were completed by each subject during a first visit and at a follow-up examination 2 yr later, and the two compared. Results showed that the overall measure of agreement between the two visits is substantial (average kappa, kappa = 0.80). Variation by gender and age were minimal. Questions regarding allergy to medications, oral treatment, reason for tooth extraction, health symptoms and history of systemic diseases exhibited high levels of agreement (kappa ranged from 0.71-0.90). Information on vitamin and mineral intake yielded kappa = 0.63. Oral conditions scored the lowest but were still acceptable (kappa = 0.57). These findings indicate that there were no significant discrepancies in self-reported responses to the health questionnaire used in the ECPD Study. Although the information provided by the subject may not be as accurate as compared to laboratory testing, it is nevertheless a reliable source of information which can be utilized cost-effectively in research studies. 相似文献
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This is the first report showing VIP fibers in the optic chiasm and the optic nerves of intact rats. These fibers form a fan-shaped dorso-medial bundle in the optic nerves. After colchicine injection into the vitreous body VIP fibers could be followed farther in the optic nerve toward the eye when compared to intact rats. After removal of eyes (enucleation) the VIP fiber-bundle became more prominent and VIP immunoreactive perikarya appeared in the supraoptic and para ventricular nuclei. When five-nine months after the enucleation Phaseolus vulgaris leucoagglutinin was administered to the paraventricular or supraoptic area, the anterogradely transported tracer was demonstrated in the optic nerve. These observations suggest the existence of a hypothalamic projection to the eye, which is, at least in part, VIP immunoreactive. 相似文献
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NS Levitt D Bradshaw MF Zwarenstein AA Bawa S Maphumolo 《Canadian Metallurgical Quarterly》1997,14(12):1073-1077
This study was undertaken to investigate the prevalence of diabetes complications and level of glycaemic and blood pressure control in Black African patients at the primary care level in the public sector Cape Town, South Africa. A stratified random sample of 300 patients attending the three largest ambulatory diabetes clinics in community health centres in Black African residential areas of Cape Town (100 patients from each) during the last 6 months of 1992 was selected. Each patient had a clinical examination, interview, and 1 year retrospective record review. Eighty-one per cent of the sampled patients were reviewed, 90% were non-insulin-dependent (NIDDM) and 10% were treated with insulin. The mean duration of diabetes was 8 (range 0-28) years. Acceptable glycaemic control was present in 49.4% (95% Confidence Intervals 45.6-53.5) of patients while 38.5% (CI 24.8-52.2) of hypertensive patients had acceptable blood pressure control. The prevalence of any grade of retinopathy was 55.4% (CI 48.90-62.9), proliferative and preproliferative retinopathy 15.6% (CI 8.5-22.8), cataracts 7.9% (CI 4.4-11.4), peripheral neuropathy 27.6% (CI 15.2-39.4), absent foot pulses 8.2% (CI 5.2-12.6), amputations 1.4% (CI 0.4-2.4), persistent proteinuria 5.3% (CI 2.5-8.1) and an elevated albumin-creatinine ratio 36.7% (CI 29.0-44.4). The complications were not documented in the clinic records of the preceding year with the exception of 1 patient with absent foot pulses and the 12 patients with proteinuria. The high prevalence of suboptimal glycaemic and blood pressure control as well as complications of diabetes, largely unrecorded in the preceding years' clinic notes, demonstrates the deficiency of and need for preventative diabetes care at the primary care level. The design, institution, and evaluation of effective intervention programmes are a priority to improve the quality of care provided and the health of diabetic patients. 相似文献
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