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S R Wise  M Quigley  A W Saxe  M J Zdon 《Surgery》1990,108(6):1058-63; discussion 1063-4
Patients with hyperparathyroidism appear to be a particular risk for peptic ulcer disease. To test the hypothesis that hypercalcemia or parathyroid hormone plays a role in promoting ulcer disease, we studied the effect of varying concentrations of extracellular calcium on acid secretion using in vitro isolated rabbit gastric glands. Acid secretion was assessed by the accumulation of carbon 14-labeled aminopyrine (14C-AP). Glands were incubated with varying calcium concentrations in the unstimulated state and with histamine or carbachol (10(-7) to 10(-4) mol/L) in 1 or 2 mmol/L calcium medium. The effect of parathyroid hormone was also examined under identical conditions. Compared to 1 mmol/L standard calcium medium, unstimulated 14C-AP accumulation was significantly inhibited (p less than 0.05) at both lower (0.33 mmol/L) and higher (2 and 2.5 mmol/L) calcium concentrations. Accumulation of 14C-AP in response to histamine stimulation was unaffected by alteration of extracellular calcium (p greater than 0.2). Carbachol-stimulated 14C-AP accumulation was significantly augmented (p less than 0.01) by an increase in calcium concentration from 1 to 2 mmol/L. The addition of parathyroid hormone (10(-7) to 10(-4) mmol/L) alone or in combination with carbachol or histamine (10(-6) mmol/L) incubation did not alter 14C-AP accumulation. These data suggest that elevations in extracellular calcium play an active role in the potentiation of cholinergic-mediated gastric gland acid secretion and may thereby play a role in hyperparathyroid-related ulcer disease.  相似文献   
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Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.  相似文献   
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Fear of falling, defined as a lack of self-confidence that one may avoid falls while doing everyday activities, may have serious consequences for elderly people. This article examines the prevalence, risk factors, and consequences of fear of falling in the elderly population; methods for assessing those fears; and suggests evidence-based interventions. Incorporating successful strategies into programs to reduce falling can result in improved patient outcomes as well as decreased healthcare utilization and costs.  相似文献   
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. We invited Dr Peplau to provide a personal reflection on the recent history of psychiatric nursing and her thoughts on immediate challenges facing the profession. The paper is an individual scholar's commentary on the way that psychiatry has waxed and waned over the years, in relation to nursing. This historical review discovers and reports a challenge to current practice. Dr Peplau describes a professional shift that is pulling nurses toward the subordinate role observed earlier this century. The paper draws attention to how contemporary practice can be positively influenced, e.g., by giving a structure to the allocation and conduct of nurse–patient time.  相似文献   
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To determine if amplification of the C-erb-B2 proto-oncogene could be correlated with prognosis in carcinoid tumours, 49 pulmonary carcinoid tumours (26 typical, 23 atypical) were examined using a polyclonal antibody to the C-terminal peptide of the C-erb-B2 protein sequence. No C-erb-B2 gene product could be shown: the demonstration of C-erb-B2 does not seem to help, therefore, in determining diagnosis or prognosis in pulmonary carcinoid tumours.  相似文献   
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