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In a prospective randomized clinical trial comprising 22 postmenopausal women with backache and a halisteretic spine with crush fracture(s), 12 women completed a 12-week therapy with sodium fluoride, calcium and calciferol and 10 with placebo. A statistically significant improvement (p less than 0.05), evaluated by a four-stage scale on pains, infirmity, and consumption of analgesics, was observed in the actively treated patients. 相似文献
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Regional extraction of circulating norepinephrine, DOPA, and dihydroxyphenylglycol in humans 总被引:1,自引:0,他引:1
D S Goldstein R O Cannon A Quyyumi P Chang M Duncan J E Brush G Eisenhofer 《Journal of the autonomic nervous system》1991,34(1):17-35
Dihydroxyphenylglycol (DHPG) is the main intraneuronal metabolite of the sympathetic neurotransmitter, norepinephrine (NE), and dihydroxyphenylalanine (DOPA) the immediate product of the rate-limiting step in catecholamine biosynthesis. Simultaneous measurements of regional rates of appearance (spillovers) of NE, DOPA, and DHPG in plasma have the potential to provide unique information about aspects of sympathoneural function but have not actually been measured in humans. In the present study, spillovers of DHPG, DOPA, and NE in the heart, head, leg, and lungs, were estimated from regional extraction fractions of infused [3H]-1-NE, DHPG, and [13C6]DOPA or unlabelled DOPA in humans during cardiac catheterization. There was little cardiac extraction of DHPG (7 +/- SEM 2%) or DOPA (8 +/- 4%) but substantial extraction of NE (69 +/- 4%). Values for cardiac spillover of DHPG and DOPA therefore were similar to values for the arteriovenous increment times plasma flow (arteriovenous production rate), whereas the cardiac spillover of NE averaged about 7-times the NE arteriovenous production rate. Cardiac DHPG spillover (28 +/- 3 ng/min) exceeded the spillovers of NE (9 +/- 2 ng/min) and DOPA (15 +/- 4 ng/min). In contrast, cranial DOPA spillover (159 ng/min) exceeded those of NE and DHPG by 8- and 2-fold and accounted for about 1/10 of the total spillover of DOPA into arterial plasma. In the femoral vascular bed, arteriovenous production rates of NE and DHPG were unrelated to femoral spillovers of NE and DHPG. Arterial and regional clearances of [13C6]DOPA were similar to those of unlabelled DOPA. The results suggest that (1) endogenous NE, DOPA, and DHPG all are released into the bloodstream by the heart, head, and limbs of humans; (2) DHPG and DOPA are not co-released with NE; (3) cardiac arteriovenous production rates of DOPA and DHPG can be used to indicate cardiac spillover of these catechols, whereas the cardiac NE arteriovenous production rate substantially underestimates cardiac NE spillover; and (4) estimates of limb spillover of NE and DHPG require concurrent measurements of the corresponding regional clearances. 相似文献
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Current perspectives on childhood depression: an overview 总被引:2,自引:0,他引:2
J H Kashani A Husain W O Shekim K K Hodges L Cytryn D H McKnew 《The American journal of psychiatry》1981,138(2):143-153
The rapidly increasing research interest in childhood depression indicates that it has become a recognized disorder. The authors review the literature on depression in children, focusing on epidemiology, various diagnostic criteria, classification schemes, assessment instruments, and intervention studies that have been applied to childhood depression. Given that there are many etiological factors, it will be important to study the disorder from various conceptual frameworks, including biochemical, genetic learned helplessness, life stresses, cognitive distortion, behavioral reinforcement, and sociological models. 相似文献