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A major goal of plant biotechnology is to improve the nutritional qualities of crop plants through metabolic engineering. Melatonin is a well‐known bioactive molecule with an array of health‐promoting properties, including potent antioxidant capability. To generate melatonin‐rich rice plants, we first independently overexpressed three tryptophan decarboxylase isogenes in the rice genome. Melatonin levels were altered in the transgenic lines through overexpression of TDC1, TDC2, and TDC3; TDC3 transgenic seed (TDC3‐1) had melatonin concentrations 31‐fold higher than those of wild‐type seeds. In TDC3 transgenic seedlings, however, only a doubling of melatonin content occurred over wild‐type levels. Thus, a seed‐specific accumulation of melatonin appears to occur in TDC3 transgenic lines. In addition to increased melatonin content, TDC3 transgenic lines also had enhanced levels of melatonin intermediates including 5‐hydroxytryptophan, tryptamine, serotonin, and N‐acetylserotonin. In contrast, expression levels of melatonin biosynthetic mRNA did not increase in TDC3 transgenic lines, indicating that increases in melatonin and its intermediates in these lines are attributable exclusively to overexpression of the TDC3 gene.  相似文献   
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Women with germline mutations in BRCA1 and BRCA2 genes have significantly increased lifetime risks of breast and ovarian cancer. To manage both the ovarian and breast cancer risks the current recommendation is undergo a risk reducing salpingo-oophorectomy (RRSO) prior to natural menopause. To date, studies have focussed on quality of life and sexual dysfunction in women who undergo RRSO, but few have reported on the wider physical consequences. We performed a questionnaire study in women with BRCA 1 or 2 gene mutations known to the Peter MacCallum Familial Cancer Centre. We gathered information about ovarian surgery, ongoing follow-up, management of risk factors including osteoporosis, and current severity of menopausal symptoms. Two hundred and nineteen women were surveyed. One hundred and forty-three of 157 responding participants (91?%) reported having RRSO. Sixty one were pre-menopausal at RRSO. Post surgical follow-up rates were generally low, and a minority of women reported recent bone density imaging or pharmaceutical prevention or treatment of osteoporosis. Menopausal symptoms appeared generally mild. No significant differences in symptom severity were observed in women who underwent a pre-menopausal RRSO compared to RRSO after natural menopause. These data indicate that a formalised follow-up protocol is necessary to optimally manage the consequences of a RRSO.  相似文献   
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Nursing for Women's Health convened a group of nurse researchers for a roundtable discussion about the relationship of research to the profession of nursing, how research drives evidence‐based practice and how nurses can get involved in research and in its application to the care of women and newborns.  相似文献   
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