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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
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Caroline Bolton-Smith Marion E T McMurdo Colin R Paterson Patricia A Mole Julia M Harvey Steven T Fenton Celia J Prynne Gita D Mishra Martin J Shearer 《Journal of bone and mineral research》2007,22(4):509-519
Dietary supplementation with vitamin K(1), with vitamin D(3) and calcium or their combination, was examined in healthy older women during a 2-year, double-blind, placebo-controlled trial. Combined vitamin K with vitamin D plus calcium was associated with a modest but significant increase in BMC at the ultradistal radius but not at other sites in the hip or radius. INTRODUCTION: The putative beneficial role of high dietary vitamin K(1) (phylloquinone) on BMD and the possibility of interactive benefits with vitamin D were studied in a 2-year double-blind, placebo-controlled trial in healthy Scottish women > or =60 years of age. MATERIALS AND METHODS: Healthy, nonosteoporotic women (n = 244) were randomized to receive either (1) placebo, (2) 200 microg/day vitamin K(1), (3) 10 microg (400 IU) vitamin D(3) plus 1000 mg calcium/day, or (4) combined vitamins K(1) and D(3) plus calcium. Baseline and 6-month measurements included DXA bone mineral scans of the hip and wrist, markers of bone turnover, and vitamin status. Supplementation effects were tested using multivariate general linear modeling, with full adjustment for baseline and potential confounding variables. RESULTS: Significant bone mineral loss was seen only at the mid-distal radius but with no significant difference between groups. However, women who took combined vitamin K and vitamin D plus calcium showed a significant and sustained increase in both BMD and BMC at the site of the ultradistal radius. Serum status indicators responded significantly to respective supplementation with vitamins K and D. Over 2 years, serum vitamin K(1) increased by 157% (p < 0.001), the percentage of undercarboxylated osteocalcin (%GluOC) decreased by 51% (p < 0.001), serum 25-hydroxyvitamin D [25(OH)D] increased by 17% (p < 0.001), and PTH decreased by 11% (p = 0.049). CONCLUSIONS: These results provide evidence of a modest synergy in healthy older women from nutritionally relevant intakes of vitamin K(1) together with supplements of calcium plus moderate vitamin D(3) to enhance BMC at the ultradistal radius, a site consisting of principally trabecular bone. The substantial increase in gamma-carboxylation of osteocalcin by vitamin K may have long-term benefits and is potentially achievable by increased dietary intakes of vitamin K rather than by supplementation. 相似文献
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静松灵[2-(2,4-二甲基苯胺基)-4,5-二氢噻唑,XT]是国内合成的麻醉物,经ip给药后,从大鼠尿中分离、纯化、鉴定了四个代谢产物。MB1即XT原形;MB3及MA2互为异构体,分别为2位、4位甲基氧化为羧基的产物;MA1则4位甲基氧化为羧基,二氢噻唑环中41位亚甲基氧化为羰基。初步实验表明:代谢产物MB3,MA2,MA1的药效与毒性均远低于原形药,大鼠与小鼠对XT的转化机制相近,但也存在种属的差异。 相似文献
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R L Cooper M L Mole G L Rehnberg J M Goldman W K McElroy J Hein T E Stoker 《Toxicology》1992,71(1-2):69-81
Two experiments were conducted in which the acute effects of inhaled methanol on serum hormones associated with reproductive function in the male rat were evaluated. In the first experiment, rats exposed to methanol (0, 200, 5000 and 10,000 ppm) for 6 h were killed at the end of the exposure period (6 h) or the following morning (24 h). Also, because the process of exposure itself could modify neuroendocrine function, the effect of the handling associated with placing the rat in the exposure chamber was evaluated further by dividing the exposed animals into acclimated (2 weeks of prior handling) and non-acclimated groups. At 6 h, an effect of prior handling was noted in the sham-exposed rats, with serum luteinizing hormone (LH) of the non-acclimated group being greater than that of the acclimated group. Serum LH concentrations were altered by methanol exposure, but the direction of change and the exposure level at which an effect was noted differed between the acclimated and non-acclimated rats. Methanol (5000 ppm) reduced serum LH in the non-acclimated animals, while 10,000 ppm increased LH in the acclimated rats. Follicle stimulating hormone (FSH) and testosterone were unchanged by methanol in rats killed at 6 h. Thus, this experiment did not confirm earlier reports that exposure to 200 ppm for 6 h reduced serum testosterone. At 24 h, an effect of prior handling was still present in the hormonal measures, with serum and interstitial fluid testosterone concentrations being greater in the non-acclimated rats. Also, there was a dose x handling interaction with methanol exposure inducing an increase in serum testosterone in the non-acclimated rats (up to 5000 ppm) and a decrease in the acclimated rats (up to 10,000 ppm). In the second experiment, groups of acclimated and non-acclimated rats were exposed to 0 or 5000 ppm methanol for 1, 2 and 6 h and killed immediately after removal from the chamber. Serum LH, testosterone and FSH values were not different in sham- vs methanol-exposed rats at any time point. As in experiment 1, an effect of prior handling was noted. In general, the concentrations of these hormones and serum prolactin in the non-acclimated rats were greater than those observed for acclimated rats. Methanol exposure resulted in increased prolactin concentrations under both handling conditions.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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The management of patients with asymptomatic hyperparathyroidism remains controversial. This study examined the extent to which the presence of prospect of bone disease should influence treatment. Bone mineral content (BMC) of the distal forearm was measured by single photon absorptiometry in 67 patients with mild hyperparathyroidism. Twenty-six patients treated surgically and 17 managed conservatively were reviewed regularly for up to 4 years. Eighty per cent of patients had a baseline fat-corrected BMC within the local reference interval for age and sex, but about 75 per cent of values fell below the mean. BMC at the 'distal' site of the surgically treated patients improved or stabilized, but a continuing decline was seen in the patients managed conservatively (P less than 0.01). Differences were small and concern about future osteoporotic fracture should seldom be a major factor in making decisions about surgical correction of mild hyperparathyroidism. 相似文献
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Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging. 相似文献