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BACKGROUND: Low serum 25-hydroxyvitamin D ?25(OH)D concentrations are commonly found in the elderly and are associated with hip fracture. Treatment with vitamin D and calcium can reduce the risk of fracture. The relation between the rise in parathyroid hormone (PTH) with age and the decrease in 25(OH)D is not clear. Neither is there any consensus on the serum concentration of 25(OH)D required for bone health. OBJECTIVE: Our objective was to study the relations between serum PTH, serum vitamin D metabolites, and other calcium-related variables in postmenopausal women. DESIGN: This was a cross-sectional study of 496 postmenopausal women without vertebral fractures attending our menopausal osteoporosis clinics. RESULTS: PTH was significantly positively related to age and serum 1, 25-dihydroxyvitamin D ?1,25(OH)(2)D and inversely related to 25(OH)D and plasma ionized calcium. There was a step-like increase in PTH as serum 25(OH)D fell below 40 nmol/L. In women with 25(OH)D concentrations >40 nmol/L, 1,25(OH)(2)D was positively related to 25(OH)D; in women with 25(OH)D concentrations 40 nmol/L, 1,25(OH)(2)D was most closely (inversely) related to plasma creatinine. Therefore, with serum 25(OH)D concentrations increasingly <40 nmol/L, serum 1,25(OH)(2)D becomes critically dependent on rising concentrations of PTH. CONCLUSION: The data suggest that aging women should maintain 25(OH)D concentrations >40 nmol/L (which is the lower limit of our normal range for healthy young subjects) for optimal bone health.  相似文献   
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应用改进的眼震图检查先天性眼球震颤   总被引:2,自引:0,他引:2  
目的评价改进后的眼震图对先天性眼球震颤波形的分析,为其手术治疗提供较为精确的量化标准.方法改进电生理仪的视网膜电图(EOG)程序,分别记录68例患者33cm原在位、右5°、10°、15°、20°,左5°、10°、15°、20°,3m原在位及闭眼的波形,并对其中28例手术患者术前和术后的眼震图进行比较.结果68例患者中,跳动型48例,其中水平跳动46例,垂直跳动2例;水平钟摆型20例.跳动型中,有代偿头位的40例,钟摆型无明显代偿头位.28例手术患者中,水平跳动型26例,水平钟摆型2例.26例跳动型患者均有中间位和代偿头位.术后20例代偿头位消失,6例代偿头位在左5°~10°.按震频、振幅、震强的分组中,处于中等震频、振幅、震强范围内的多见.结论改进的眼震图可以对眼震的振幅、震频、震强、中间位进行量化的检测,从而指导其治疗.  相似文献   
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Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans.  相似文献   
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BACKGROUND: The purpose of this case report is to describe the first experience with erlotinib (Tarceva) in the treatment of locally advanced vulvar cancer. CASE: Two elderly patients presented with locally advanced vulvar cancer. Surgery was not a suitable method of treatment for either of them because of multiple medical co-morbidities and stage of disease. One patient had disease progression on standard chemoradiation. Erlotinib, an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, was tried in both cases and dramatic responses were observed. CONCLUSION: Therapy targeted to EGFR may be effective in the treatment of locally advanced vulvar cancer. This new therapeutic approach deserves further evaluation in carefully designed studies.  相似文献   
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