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PURPOSE: There is limited support for the validity and reproducibility of dietary assessment in culturally diverse populations. The goal of this study was to evaluate the comparative validity and reproducibility of a Food Frequency Questionnaire (FFQ) used in the observational, multi-cultural Insulin Resistance Atherosclerosis Study (IRAS). METHODS: Women (n = 186) were approximately equally distributed by ethnicity from one urban center (African Americans and non-Hispanic whites) and one rural center (Hispanics and non-Hispanic whites). The IRAS FFQ was modified from the National Cancer Institute Health Habits and History Questionnaire to include ethnic and regional foods. Validity was assessed by comparing dietary values, including supplements, obtained from the FFQ to the average intake estimated from a series of 8 24-hour dietary recalls collected by telephone over the same 1-year period. Reproducibility was assessed among women who reported no change in their usual diet (n = 133) by comparing data from the original IRAS FFQ (in-person) with the FFQ administered for the validity study (two to four years later, by telephone). RESULTS: Correlation coefficients for validity were statistically significant for most nutrients (mean r = 0.62 urban non-Hispanic white, 0.61 rural non-Hispanic whites, 0.50 African American, 0.41 Hispanic) and did not differ among subgroups of obesity or diabetes status. The median correlation coefficient for the total sample was 0.49. Correlations were lower for women with less than 12 years of education (mean r = 0.30; median r = 0.25). The lower correlations among Hispanics was largely explained by the lower educational attainment in that sample. For reproducibility, the mean correlation for nutrients evaluated was r = 0.62 (median r = 0.63) and did not differ for subgroups. CONCLUSIONS: Although educational attainment must be considered, the IRAS FFQ appears to be reasonably valid and reliable in a diverse cohort.  相似文献   
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骨髓干细胞分化为肝细胞的多种移植途径   总被引:3,自引:0,他引:3  
近年来许多研究证实,人类和啮齿类动物的骨髓细胞可分化为多种细胞类型,包括骨骼肌细胞、心肌细胞、神经细胞和肝细胞等,这些骨髓干细胞的可塑性研究,为肝细胞移植提供了新的供体来源.骨髓干细胞替代肝细胞进行移植具有来源丰富,费用相对低廉,对患者损伤小等优点,且自体骨髓干细胞移植可以完全避免移植排斥反应,同时,骨髓干细胞只有 5-15 μm,移植后不会发生栓塞等并发症.因此骨髓干细胞移植在治疗肝病以及解决供体肝脏来源短缺方面具有广泛的应用前景.本文就骨髓干细胞的移植途径做一综述.  相似文献   
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Breast cancer has been suggested to potentially have prenatal origins. We examined associations between birth weight, body mass index (BMI) at four-time points over 25 years of adulthood, and risk of postmenopausal breast cancer, with emphasis on whether the association between birth weight and risk of breast cancer was mediated by weight and height changes over the adult life course. Postmenopausal women (n = 70,397) aged 50–79 years without breast cancer at enrollment (1993–1998) were followed up to 25 years. Weight and height were measured at baseline. Birth weight, and weights at ages 18, 35 and 50 were self-reported. Breast cancer cases were centrally adjudicated. Compared to women with birth weight of 6–8 pounds, women with birth weight of <6 pounds had lower risk of breast cancer (HR = 0.88 95% CI: 0.79–0.99). 44% and 21% of the relationship between birth weight and breast cancer risk was mediated by adult height and weight at baseline, respectively. Birth weight of 8 pounds or more was not associated with risk of postmenopausal breast cancer. Weight gain in adulthood was associated with increased risk of breast cancer regardless of time periods. In conclusion, lower birthweight was associated with lower risk of postmenopausal breast cancer, and this reduction in risk was significantly mediated by childhood or adolescent growth, especially by adult height. Our data suggest that reaching and maintaining a healthy weight during adulthood is key in the prevention of breast cancer.  相似文献   
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目的:目前临床进行隧道法舌根射频治疗时,其作用参数的设置仍缺乏统一的标准,故通过计算机三维重建射频损伤区域,分析猪舌根射频损伤体积与射频能量、时间的关系,从中得出应用舌根隧道法射频治疗的最佳作用能级和作用时间。 方法:实验于2006-06/2007-05在上海交通大学耳鼻喉科研究所完成。将36只实验用猪以射频作用能级1,2,3,4,5,6随机分成6组,每组6头猪,各个猪舌的作用时间分别设置为2,5,10,15,20,25s。用Coblation射频发生仪及Reflex55刀头进行猪舌根射频操作。射频作用后的舌根组织行连续冰冻切片,苏木精-伊红染色后,进行序列组织切片的全貌二维图像采集,对拟重建的结构进行边界提取和图像分割。将提取分割图像导入Image-Pro Solution图像处理软件,利用3D Constructor插件进行三维重建,并根据设定参数进行体积计算。用SPSS10.0统计学软件对所测数据进行统计学分析。 结果:①作用能级固定时,舌根组织射频损伤体积随时间延长而增大,符合Logarithmic回归曲线。②作用时间固定时,舌根组织射频损伤体积随能级增大而增大,符合直线回归。③射频损伤体积随能量增大而增加亦符合Logarithmic回归曲线。④Coblation射频治疗系统在能级6时,在作用10s之前,损伤体积随作用时间增加而迅速增加,其后变化趋势平缓,超过20s后损伤体积无显著增加。 结论:①舌根区域射频治疗时,舌根组织射频损伤体积与时间或能量呈Logarithmic曲线相关,与能级呈直线相关。②Coblation射频治疗系统在能级6时,最佳作用时间范围为10-20s。  相似文献   
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EDITORIAL COMMENT: We accepted this paper for publication because the authors have explored the possible value of ultrasound versus clinical assessment of fetal size to see whether they can predict the need for Caesarean section when the baby is large. In this study both the ultrasound and the clinical assessment were impressively accurate and fetal femur length was the most accurate of the ultrasound parameters in assessing fetal weight in predicting the need for Caesarean section. However, as the authors indicate, none of these methods of assessment of fetal size are recommended as an absolute indication for Caesarean section. Every obstetrician uses clinical assessment of the fetus when evaluating management of the patient but the need for clinical judgment remains.
Summary: One hundred and five women with singleton pregnancies and cephalic presentation were assessed. Fundal height and a clinical estimate of fetal weight were recorded. The fetal biparietal diameter, abdominal circumference and femur length were measured with ultrasound. Ultrasound estimated fetal weight was calculated using 3 different formulas (Shepard, Campbell and CUHK). The liquor volume was assessed using the amniotic fluid index.
Ultrasound was able to predict Caesarean section with more reliability than clinical assessment of fetal size or weight. The biparietal diameter, fundal height and amniotic fluid index were poor predictors of mode of delivery. The measurements which best predicted the mode of delivery were the fetal femur length and abdominal circumference. Femur length, but not abdominal circumference, was a statistically better predictor of Caesarean section than clinical estimation of fetal weight. There was no improvement in prediction using ultrasound estimated fetal weight.  相似文献   
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师丙帅  宫民庄  朱二霞 《医学争鸣》2005,26(16):1459-1459
1临床资料我们1999-06/2004-10收治女性出口处梗阻性便秘176例,其中耻骨直肠肌肥厚、直肠黏膜内脱垂、直肠前突三者并存57例,占32.4%,均为经产妇;年龄26~76岁,分娩1~5胎;病程1~32 a.合理的肠道及阴道准备,体位为膀胱截石位.用络合碘消毒阴道及肛管直肠腔.  相似文献   
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高三尖杉酯碱在大鼠及兔肝微粒体的代谢研究   总被引:1,自引:0,他引:1  
崔燕岩  王慕邹 《药学学报》1991,26(4):274-279
采用动物肝微粒体体外代谢法对高三尖杉酯碱进行了代谢转化的研究。应用梯度洗脱—反相HPLC结合二极管陈列检测器对体外代谢体系进行了分析。判定在体外代谢体系中,高三尖杉酯碱主要产生一个代谢产物。用HPLC法制备出一定量代谢物纯品,经光谱分析及与化学制备的对照品相比较,推定其代谢物结构为:2′-羟基-2′(α-乙酸)-6′-甲基-6′-羟基-庚酰三尖杉碱。  相似文献   
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