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81.
82.
Weimin Hu Deborah Kelly Barnard Esther Parker Ann Thomas 《环境与职业医学》2007,24(1):117-119
A drinking water supply is a complicated system in its construction,operation,maintenance and need for public health surveillance. 相似文献
83.
An intraperitoneal injection of the preferential opiate receptor agonist (+/-) bremazocine HCl given to male rough-skinned newts acutely and dose-dependently reduced their spontaneous locomotor activity. Inversely, and contrary to the situation generally observed in other vertebrates, administration of the opiate receptor antagonist naloxone HCl dose-dependently and acutely stimulated locomotion. Given at a behaviorally active dosage, naloxone counteracted the inhibitory effect of bremazocine on locomotion. The behavioral influence of the two substances was observed using two different sampling techniques (continuous recording for 3 minutes: repeated instantaneous sampling for 60 minutes). These data are discussed in view of our current knowledge on the opiate regulation of locomotor activity in vertebrates. 相似文献
84.
Nonvoluntary sexual activity among adolescents 总被引:3,自引:0,他引:3
Data from the 1987 round of the National Survey of Children indicate that seven percent of Americans aged 18-22 have experienced at least one episode of nonvoluntary sexual intercourse. Women were more likely than men to report having had such an experience, with just under half of all nonvoluntary experiences among women occurring before the age of 14. Multiple classification analysis reveals that white women who had lived apart from their parents before age 16, those who had been brought up in poverty, those who had had a physical, emotional or mental limitation when they were young, those whose parents had been heavy drinkers, those whose parents had used illegal drugs and those whose parents had smoked cigarettes when they themselves were teenagers were at significantly greater risk for experiencing sexual abuse. Six percent of young white women with no risk factors, nine percent of those with one, 26 percent of those with two, and 68 percent of those with three or more had been sexually abused before or during adolescence. 相似文献
85.
Peter A. Blume DPM FACFAS J. Christopher Moore DPM David C. Novicki DPM FACFAS 《The Journal of foot and ankle surgery》2005,44(1):44-48
There are a number of proposed causes and treatment approaches for digital mucoid cysts. The described treatment outcomes for this cyst have been variable, with the highest success rate reported with complete excision and single-lobe skin flap closure. This report describes a bilobed flap reconstruction in conjunction with resection of the head of the middle phalanx. A retrospective review was undertaken to evaluate the recurrence rate, complications, and patient satisfaction with this combined procedure. Fifteen patients with an average follow-up of 4.6 years were evaluated. There were no recurrences, flap failures, or other major complications. The use of this flap allows for greater exposure than traditional semi-elliptical incisions while allowing the wide excisional defects to be closed primarily. 相似文献
86.
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88.
Thyroid-stimulating hormone restores bone volume, microarchitecture, and strength in aged ovariectomized rats. 总被引:2,自引:0,他引:2
T Kuber Sampath Petra Simic Rebecca Sendak Natasa Draca Ann E Bowe Stephen O'Brien Susan C Schiavi John M McPherson Slobodan Vukicevic 《Journal of bone and mineral research》2007,22(6):849-859
We show the systemic administration of low levels of TSH increases bone volume and improves bone microarchitecture and strength in aged OVX rats. TSH's actions are mediated by its inhibitory effects on RANKL-induced osteoclast formation and bone resorption coupled with stimulatory effects on osteoblast differentiation and bone formation, suggesting TSH directly affects bone remodeling in vivo. INTRODUCTION: Thyroid-stimulating hormone (TSH) receptor haploinsufficient mice with normal circulating thyroid hormone levels have reduced bone mass, suggesting that TSH directly affects bone remodeling. We examined whether systemic TSH administration restored bone volume in aged ovariectomized (OVX) rats and influenced osteoclast formation and osteoblast differentiation in vitro. MATERIALS AND METHODS: Sprague-Dawley rats were OVX at 6 months, and TSH therapy was started immediately after surgery (prevention mode; n = 80) or 7 mo later (restoration mode; n = 152). Hind limbs and lumbar spine BMD was measured at 2- or 4-wk intervals in vivo and ex vivo on termination at 8-16 wk. Long bones were subjected to microCT, histomorphometric, and biomechanical analyses. The direct effect of TSH was examined in osteoclast and osteoblast progenitor cultures and established rat osteosarcoma-derived osteoblastic cells. Data were analyzed by ANOVA Dunnett test. RESULTS: In the prevention mode, low doses (0.1 and 0.3 microg) of native rat TSH prevented the progressive bone loss, and importantly, did not increase serum triiodothyroxine (T3) and thyroxine (T4) levels in aged OVX rats. In restoration mode, animals receiving 0.1 and 0.3 microg TSH had increased BMD (10-11%), trabecular bone volume (100-130%), trabecular number (25-40%), trabecular thickness (45-60%), cortical thickness (5-16%), mineral apposition and bone formation rate (200-300%), and enhanced mechanical strength of the femur (51-60%) compared with control OVX rats. In vitro studies suggest that TSH's action is mediated by its inhibitory effects on RANKL-induced osteoclast formation, as shown in hematopoietic stem cells cultivated from TSH-treated OVX rats. TSH also stimulates osteoblast differentiation, as shown by effects on alkaline phosphatase activity, osteocalcin expression, and mineralization rate. CONCLUSIONS: These results show for the first time that systemically administered TSH prevents bone loss and restores bone mass in aged OVX rats through both antiresorptive and anabolic effects on bone remodeling. 相似文献
89.
Effects of sex and age on bone microstructure at the ultradistal radius: a population-based noninvasive in vivo assessment. 总被引:8,自引:0,他引:8
Sundeep Khosla B Lawrence Riggs Elizabeth J Atkinson Ann L Oberg Lisa J McDaniel Margaret Holets James M Peterson L Joseph Melton 《Journal of bone and mineral research》2006,21(1):124-131
In a population-based cross-sectional study, we examined effects of sex and age on bone microstructure at the wrist using high-resolution 3-D pQCT. Compared with women, men had thicker trabeculae in young adulthood and had less microstructural damage with aging. These findings may contribute to the virtual immunity of men to age-related increases in wrist fractures. INTRODUCTION: Although changes in bone microstructure contribute to fracture risk independently of BMD, it has not heretofore been possible to assess this noninvasively in population-based studies. MATERIALS AND METHODS: We used high-resolution 3-D pQCT imaging (voxel size, 89 mum) to define, in a random sample of women (n = 324) and men (n = 278) 21-97 years of age, sex and age effects on bone microstructure at the wrist. RESULTS: Relative to young women (age, 20-29 years), young men had greater trabecular bone volume/tissue volume (BV/TV; by 26%, p = 0.001) and trabecular thickness (TbTh; by 28%, p < 0.001) but similar values for trabecular number (TbN) and trabecular separation (TbSp). Between ages 20 and 90 years, cross-sectional decreases in BV/TV were similar in women (-27%) and in men (-26%), but whereas women had significant decreases in TbN (-13%) and increases in TbSp (+24%), these parameters had little net change over life in men (+7% and -2% for TbN and TbSp, respectively; p < 0.001 versus women). However, TbTh decreased to a greater extent in men (-24%) than in women (-18%; p = 0.010 versus men). CONCLUSIONS: Whereas decreases with age in trabecular BV/TV are similar in men and women, the structural basis for the decrease in trabecular volume is quite different between the sexes. Thus, over life, women undergo loss of trabeculae with an increase in TbSp, whereas men begin young adult life with thicker trabeculae and primarily sustain trabecular thinning with no net change in TbN or TbSp. Because decreases in TbN have been shown to have a much greater impact on bone strength compared with decreases in TbTh, these findings may help explain the lower life-long risk of fractures in men, and specifically, their virtual immunity to age-related increases in distal forearm fractures. 相似文献
90.
Spencer Moore Cynthia Smith Tammy Simpson Sharlene Wolbeck Minke 《BMC health services research》2006,6(1):141