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We reviewed all English-language articles on associations among circulating levels of the insulin-like growth factors (IGF) and their binding proteins (IGFBP), polymorphisms in their genes, and breast cancer risk. In premenopausal women, five of eight IGF-I studies and four of six IGFBP-3 studies of circulating levels found that women in the highest quantile had more than twice the risk of developing breast cancer of those in the lowest, although in some this effect was only apparent at young ages. In postmenopausal women, however, there was no consistent effect. A simple sequence length polymorphism 1 kb 5' to IGF-I was examined in relation to circulating levels of IGF-I (12 studies) or breast cancer risk (4 studies), but there was no convincing evidence of any effect. For an A/C polymorphism 5' to IGFBP-3, all three studies were consistent with a modest effect on circulating levels, but no evidence of a direct effect on breast cancer risk was seen in the only relevant study. Variation within the reference range of IGF-I and IGFBP-3 may confer only modest increases in breast cancer risk, and any single polymorphism may only account for a small proportion of that variation. Nevertheless, population attributable fractions for high circulating levels of IGF-I and IGFBP-3 and for common genetic variants could be substantial. Further large studies, or combined analysis of data from existing studies, are needed to quantify these effects more precisely.  相似文献   
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BackgroundDentists may choose to integrate intraoral scanners (IOSs) into their practices, but there are many different IOS technologies and system generations to choose from, posing a challenge for dentists who want to invest in them.MethodsA survey of IOS use rates, advantages, satisfaction, and training was developed and deployed through Qualtrics to the 968 members of the American Dental Association Clinical Evaluators (ACE) Panel on February 19, 2021. Nonrespondents were sent reminders, and data were analyzed in SAS Version 9.4 (SAS).ResultsA total of 369 panelists responded to the survey. IOS use was split among the ACE Panel; 53% indicated they use one in their practice. The top reason respondents began using IOSs was to improve clinical efficiency (70%). Ninety percent of respondents use IOSs for single tooth-supported crowns, and 58% began using IOSs less than 4 years ago. Most users are at least mostly satisfied (91%) with the results. Among nonusers, the top reason for not using an IOS was the high level of financial investment (66%); 34% and 40% of nonusers are thinking of buying or training with IOSs in 2021, respectively.ConclusionsUptake of IOSs is split; most users are satisfied with their results, and nonusers cited financial barriers as the most common reason for not investing in one.Practical ImplicationsAs IOSs continue to penetrate the market and dentists are faced with a decision whether to invest in one, they will need guidance on how to choose the most appropriate device for their patients.  相似文献   
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The purpose of the current study was to identify effects of neurodevelopmental stimulation as administered by board certified music therapists to premature infants admitted to the neonatal intensive care unit. Premature infants (N = 108) admitted and meeting inclusion criteria were included. Experimental subjects received the developmental multimodal stimulation protocol paired with live singing (n = 25) or live singing with guitar accompaniment (n = 29). The no contact control group received standard neonatal intensive care unit care (n = 54). An ANCOVA analyses with birth weight as a covariate resulted in significant main effects found for infant length of stay (p < .05). When comparing the means, differences were found between gender and types of music paired with the developmental multimodal stimulation. The results of this study suggest an increase in neurodevelopment for infants receiving developmental multimodal stimulation as hypothesized.  相似文献   
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