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21.
To determine the effect of calcium supplementation on parathyroid hormone levels (PTH) in a group of elderly subjects at risk for developing Type II (senile) osteoporosis, 40 healthy volunteers participated in a randomized double-blind crossover study. Calcium carbonate or placebo was administered for 4 weeks, followed by a 4-week administration of the alternative intervention. Fasting blood samples and 24-hour urine collections were obtained at baseline, and at the end of each intervention period. Calcium supplementation (1000 mg/day) decreased serum PTH levels from a mean of 50.1 +/- 3.0 pg/ml to 41.9 +/- 2.4 pg/ml (p less than .001). Additionally, urine calcium excretion significantly increased during calcium administration (from 3.64 mmol/mmol creatinine at baseline to 4.28 mmol/mmol creatinine), but creatinine clearances and serum calcium levels remained unchanged. Type II osteoporosis has been associated with age-related increases in PTH levels. We have demonstrated the ability of increased calcium intake to decrease these levels, which may have implications for the management of a subset of patients with involutional osteoporosis.  相似文献   
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Betel nut is one of the mostly widely used substances in the world, particularly across Asia. Arecoline, a partial muscarinic agonist, has been hypothesized to have beneficial effects on both positive and negative symptoms of schizophrenia. This study aims to further explore associations between betel use and symptoms of schizophrenia in a 4-month longitudinal study in Nepal. Sixty Nepali patients with schizophrenia were recruited from regional outpatient clinics. The Positive and Negative Syndrome Scale (PANSS) and the Social Adaptation Self-Evaluation Scale were used to assess symptoms and social functioning in regular betel users and non-users. No significant group differences or dose–response relationships were noted on either initial or follow-up assessments. Stratifying by sex also failed to reveal an association between symptoms and betel use, which stands in contrast with previously reported data from Micronesia. There were no differences seen in social functioning other than a significantly higher proportion of betel users holding jobs. It was also noted that significantly fewer betel chewers were taking anti-cholinergic medication, which may tentatively indicate a potentially therapeutic role in the future for partial muscarinic agonists in the treatment of medication-induced movement disorders.  相似文献   
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Radiographic mottle and patient exposure in mammography   总被引:1,自引:0,他引:1  
Barnes  GT; Chakraborty  DP 《Radiology》1982,145(3):815
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J D Bales 《Ear and hearing》1989,10(2):109-111
A case is presented of a patient with lateral pontine stroke which resulted in a moderate unilateral sensorineural hearing loss. ABR, word recognition scores, acoustic reflexes, neurological evaluation, and CT scan were consistent with brain stem lesion. Recovery of hearing, including acoustic reflexes and word recognition ability, occurred 2 months after the stroke.  相似文献   
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