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ObjectiveThe objective of this study was to learn about the experiences of principals and school food service directors with the Texas Public School Nutrition Policy.DesignSemistructured qualitative interviews were conducted to gain first hand reactions to the new nutrition policy.SettingData were gathered from Texas middle schools.ParticipantsPrincipals and food service directors from 24 schools randomly selected from 10 Texas Education regions were interviewed.Phenomenon of InterestParticipants were interviewed about their reactions to the implementation of the Texas School Nutrition Policy.AnalysisTwo researchers, using thematic analysis, independently analyzed each interview. Differences in coding were reconciled and themes were generated.ResultsThe themes that surfaced included resistance to the policy, policy development process, communication, government role, parental role, food rewards, fund raising, and leadership.Conclusions and implicationsResistance to the policy was not extreme. In the future a wider array of school personnel who are affected by school food regulations should be included in the development of new policies. It is critical to communicate with all concerned parties about the policy.  相似文献   
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Neurogenesis is nearly completed after birth, whereas gliogenic activities remain intense during the postnatal period in the developing rat cortex. These include involution of radial glia, proliferation of astrocytes and oligodendrocytes and myelin formation. Little is known about the effects of hypoxic–ischemic (HI) injury on these critical postnatal processes. Here we explored the glial reactions to mild HI injury of the neonatal rat cerebral cortex at P3. We show that the HI lesion results in disruption of the normal radial glia architecture, which was paralleled by an increase in GFAP immunopositive reactive astrocytes. The morphology of these latter cells and the fact that they were immunolabelled for both nestin and GFAP suggest an accelerated transformation of radial glia into astrocytes. In addition, BrdU/GFAP immunostaining revealed a significant increase of double-labelled cells indicating an acute proliferation of astrocytes after HI. This enhanced proliferative activity of astrocytes persisted for several weeks. We found an elevated number and increased mitotic activity of both NG2-positive oligodendrocyte progenitors and RIP-positive oligodendrocytes after injury. These findings imply that glial responses are central to cortical tissue remodelling following neonatal ischemia and represent a potential target for therapeutic approaches.  相似文献   
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Background. Delivery of home parenteral nutrition (PN) is typically cycled over 12 hours. Discharge to home on PN is often delayed due to potential adverse events (AEs) associated with cycling PN. The purpose was to determine whether patients requiring long‐term PN can be cycled from 24 hours to 12 hours in 1 day instead of 2 days without increasing the risk of PN‐related AEs. Methods. Hospitalized patients receiving PN at goal calories infused over 24 hours without severe electrolyte or blood glucose abnormalities were eligible. Patients were randomly assigned to a 1‐step “fast‐track” protocol or 2‐step “standard” protocol. AEs were defined as hypoglycemia or hyperglycemia, new‐onset or worsening dyspnea, tachycardia, tachypnea, lower extremity or sacral edema, pulmonary edema, or abdominal ascites and were graded as minor or major. Results. In the 63 patients studied, the most prevalent PN‐related AE was hyperglycemia, occurring in 24.2% and 30.0% of patients in the fast‐track and standard groups, respectively. Overall, there was no significant difference in the prevalence of PN‐related minor AEs between fast‐track and standard groups (33.3% and 53.3%, P = .5). No major PN‐related AEs occurred in the fast‐track group, while 1 major PN‐related AE (pulmonary edema) occurred in the standard group. Conclusions. Fast‐track cycling is as safe as standard cycling in patients without diabetes mellitus or major organ dysfunction requiring long‐term PN. Fast‐track cycling could potentially expedite hospital discharge, resulting in decreased healthcare costs and improved patient satisfaction.  相似文献   
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A well-documented case of non-mosaic Turner syndrome, with spontaneous pubertal development and ovulatory cycles is reported. Mosaicism could be excluded both by karyotyping of 172 metaphases of blood lymphocytes and fibroblasts, and by fluorescence in situ hybridization, using an X-centromeric probe, in 200 blood lymphocyte nuclei. This Turner syndrome patient underwent normal pubertal development, with spontaneous menarche at 14 years, followed by regular monthly periods. Hormonal measurements performed during puberty were consistent with the patient's pubertal development. At the age of 26 years the patient was referred for complete fertility evaluation. Detailed hormonal analyses were performed in a given cycle. They showed midluteal phase estradiol and progesterone values within the range corresponding to normal ovulation and corpus luteum function. In the same cycle, pelvic ultrasonography was also performed at days 13, 15 and 18. It demonstrated a spontaneous ovulation, with follicular rupture that occurred between days 15 and 18. This is the first report of a spontaneous ovulation in Turner syndrome evidenced, not only by hormonal analysis, but also by ultrasonographic demonstration of follicular rupture.  相似文献   
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High molecular weight antigen (HMWA) is a tumor-associated proteoglycan of human malignant melanoma. I-131 labeled Fab fragments of these specific antibodies were used for preliminary feasibility studies for radioimmunodetection and therapy of human subjects who had inoperable metastatic melanoma. Ten patients received tracer doses of 5-13 mCi (185-481 MBq) of I-131 (anti-HMWA) Fab. All patients (8/8) who had melanoma lesions greater than 1 cm by correlative diagnostic methods had one or more lesions that had localization to tumor of the radiolabeled Fab. In all, 17 of 23 (74%) documented metastases were seen. There were no false positives in this series. Two patients who had avid uptake received potentially radiotherapeutic doses of 142 mCi (5,254 MBq) (one patient) and 181 mCi (6,697 MBq) and 193 (7,141 MBq) (total: 374 mCi or 13,838 MBq) (one patient). For both of these patients, whole body imaging studies showed that the localization of the high dose I-131 Fab was predominantly in tumor. The patient who received the larger dose showed a greater than 50% reduction in the size of pelvic and pericaval nodes, with stabilization of disease at the smaller nodal size for a period of three months. On whole body images, the anti-Fab HMWA appears to be more tumor selective than Fab preparations that target the p97 antigen for melanoma, and there is less uptake in liver.  相似文献   
100.
Extremely preterm infants commonly show brain injury with long‐term structural and functional consequences. Three‐day‐old (P3) rat pups share some similarities in terms of cerebral development with the very preterm infant (born at 24–28 weeks of gestation). The aim of this study was to assess longitudinally the cerebral structural and metabolic changes resulting from a moderate neonatal hypoxic ischemic injury in the P3 rat pup using high‐field (9.4 T) MRI and localized 1H magnetic resonance spectroscopy techniques. The rats were scanned longitudinally at P3, P4, P11, and P25. Volumetric measurements showed that the percentage of cortical loss in the long term correlated with size of damage 6 h after hypoxia–ischemia, male pups being more affected than female. The neurochemical profiles revealed an acute decrease of most of metabolite concentrations and an increase in lactate 24 h after hypoxia–ischemia, followed by a recovery phase leading to minor metabolic changes at P25 in spite of an abnormal brain development. Further, the increase of lactate concentration at P4 correlated with the cortical loss at P25, giving insight into the early prediction of long‐term cerebral alterations following a moderate hypoxia–ischemia insult that could be of interest in clinical practice. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
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