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排序方式: 共有690条查询结果,搜索用时 187 毫秒
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M K Javaid K M Godfrey P Taylor S R Shore B Breier N K Arden C Cooper 《Journal of bone and mineral research》2004,19(1):56-63
IGF-1 is a key growth factor during fetal life. Using DXA, we found that the concentration of IGF-1 in umbilical cord serum is strongly related to neonatal whole body bone mineral content, lean mass, and fat mass. However IGF-1 did not explain the relationships of maternal smoking, fat mass, and physical activity with neonatal bone mass. The study supports a direct role for circulating IGF-1 in growth of the fetal skeleton. INTRODUCTION: Evidence is accumulating that the risk of osteoporosis in later life may be determined in part by environmental influences during intrauterine and early postnatal life. We previously reported that maternal birthweight, smoking, fat stores, and physical activity during pregnancy predict neonatal bone mass. While the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis is an important determinant of postnatal skeletal growth, there are few data relating the concentration of growth factors in umbilical cord blood to bone mineral content (BMC) and other indices of body composition in the newborn infant. MATERIALS AND METHODS: We conducted a population-based study in a cohort of full-term, newborn infants whose mothers were characterized for lifestyle, body composition, and nutrition through their normal pregnancies. In a sample of 119 infants from the cohort, we related cord serum IGF-1 and insulin-like growth factor binding protein (IGFBP)-3 concentrations to neonatal body composition measured by DXA and evaluated the extent to which this cytokine mediates the previously reported effects of maternal diet and lifestyle on neonatal bone mass. RESULTS: There were strong positive associations between cord serum IGF-1 concentration and whole body BMC (r = 0.38, p < 0.001), whole body lean mass (r = 0.40, p < 0.001), and whole body fat mass (r = 0.50, p < 0.001) after adjusting for gestational age and sex. There was no association between cord serum IGF-1 and BMC adjusted for bone size. Neither cord serum IGF-1 nor IGFBP-3 explained the relationships that we previously reported between maternal influences and neonatal bone mass. CONCLUSIONS: Cord serum IGF-1 is more closely related to the size of the neonatal skeleton than to its degree of mineralization. Documented maternal determinants of neonatal bone mass seem to mediate their effects independently of variations in cord serum IGF-1 in healthy pregnancies. 相似文献
143.
H C Sabelli J Fawcett F Gusovsky J I Javaid P Wynn J Edwards H Jeffriess H Kravitz 《The Journal of clinical psychiatry》1986,47(2):66-70
To test the hypothesis that 2-phenylethylamine (PEA) modulates affect, plasma levels and urinary excretion of its main metabolite, phenylacetic acid (PAA), were studied in depressed and manic subjects, and the mood-elevating effects of its precursor, L-phenylalanine, were studied in depressed subjects. Mean total plasma PAA concentrations were 491.83 +/- 232.84 ng/ml in 12 healthy volunteers and 300.33 +/- 197.44 ng/ml in 23 drug-free patients with major depression. The 24-hour urinary PAA excretion was also measured in 48 healthy volunteers (141.1 +/- 10.2 mg PAA/24 hr) and in 144 patients with major depression (78.2 +/- 41.0 mg PAA/24 hr). The results suggest that low plasma and urinary PAA may be state markers for depression and are compatible with the PEA hypothesis. In further support, phenylalanine elevated mood in 31 of 40 depressives. 相似文献
144.
H C Sabelli U N Durai J Fawcett J I Javaid 《The Journal of neuropsychiatry and clinical neurosciences》1989,1(1):37-39
Twenty-four hour urinary phenylacetic acid was high in 12 acutely psychotic schizoaffective patients (240.3 +/- 51.9 mg/day) and low in 16 acutely psychotic schizophrenic patients (53.6 +/- 15.1 mg/day). These results indicate a biochemical difference between these two types of acute psychoses and indicate alterations in phenylalanine metabolism. 相似文献
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Rohan Shad Robyn Fong Nicolas Quach Cayley Bowles Patpilai Kasinpila Michelle Li Kate Callon Miguel Castro Ashrith Guha Erik. E. Suarez Sangjin Lee Stefan Jovinge Theodore Boeve Yasuhiro Shudo Curtis P. Langlotz Jeffrey Teuteberg William Hiesinger 《The Journal of heart and lung transplantation》2021,40(8):778-785
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Mehwish Javaid Dana Ashrawi Rachel Landgren Lori Stevens Rosalind Bello Lewis Foxhall Melissa Mims Lois Ramondetta 《Journal of community health》2017,42(1):58-65
The purpose of this study was to identify barriers to and facilitators of human papillomavirus (HPV) vaccination in children aged 9–17 years across Texas. A literature review informed the development of a web-based survey designed for people whose work involves HPV vaccination in settings serving pediatric patients. The survey was used to examine current HPV vaccine recommendation practices among healthcare providers, barriers to HPV vaccination, reasons for parent/caregiver vaccine refusal, staff and family education practices, utilization of reminder and recall systems and status of vaccine administration (payment, ordering and stocking). 1132 responses were received representing healthcare providers, administrative and managerial staff. Respondents identified perceived barriers to HPV vaccination as parental beliefs about lack of necessity of vaccination prior to sexual debut, parental concerns regarding safety and/or side effects, parental perceptions that their child is at low risk for HPV-related disease, and parental lack of knowledge that the vaccine is a series of three shots. Of responding healthcare providers, 94 % (n = 582) reported they recommend the vaccine for 9–12 year olds; however, same-day acceptance of the vaccine is low with only 5 % (n = 31) of providers reporting the HPV vaccine is “always” accepted the same day the recommendation is made. Healthcare providers and multidisciplinary care teams in pediatric care settings must work to identify gaps between recommendation and uptake to maximize clinical opportunities. Training in methods to communicate an effective HPV recommendation and patient education tailored to address identified barriers may be helpful to reduce missed opportunities and increase on-time HPV vaccinations. 相似文献
148.
Organic light-emitting field-effect transistors (LEFETs) provide the possibility of simplifying the display pixilation design as they integrate the drive-transistor and the light emission in a single architecture. However, in p-type LEFETs, simultaneously achieving higher external quantum efficiency (EQE) at higher brightness, larger and stable emission area, and high switching speed are the limiting factors for to realise their applications. Herein, we present a p-type polymer heterostructure-based LEFET architecture with electron and hole injection interlayers to improve the charge injection into the light-emitting layer, which leads to better recombination. This device structure provides access to hole mobility of ~2.1 cm2 V−1 s−1 and EQE of 1.6% at a luminance of 2600 cd m−2. Most importantly, we observed a large area emission under the entire drain electrode, which was spatially stable (emission area is not dependent on the gate voltage and current density). These results show an important advancement in polymer-based LEFET technology toward realizing new digital display applications. 相似文献
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