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41.
From the Editors
Referees 相似文献42.
43.
M Kárteszi E Stark G Rappay F A László G B Makara 《The American journal of physiology》1981,240(6):E689-E693
Electrical stimulation of the neural lobe of the pituitary resulted in an increase of corticosterone secretion in both normal and Brattleboro rats. Bioassaying the corticoliberin (CRF) activity of stalk-median eminence and neural lobe extracts obtained from normal and Brattleboro rats revealed that the endogenous vasopressin was not a prerequisite of ACTH-releasing potency. Arginine-8-vasopressin failed to potentiate the CRF activity of the different extracts. These data suggest that a nonvasopressin substance(s) with CRF activity can be released from the neurohypophysis of the rat, and it may contribute to activating the pituitary-adrenal axis under certain experimental conditions. 相似文献
44.
OBJECTIVE: To examine, using direct observation methodology, differences in family functioning at mealtime between families of school-age children with cystic fibrosis (CF) and families of school-age children without a chronic illness. METHOD: Family functioning was rated using the McMaster Mealtime Interaction Coding System (MICS) during a videotaped dinner among 28 families of children with CF and 27 families of non-ill, age-matched peers. Families were rated on overall family functioning and on six dimensions of the MICS: task accomplishment, communication, affect management, interpersonal involvement, behavior control, and role allocation. RESULTS: Ratings for families of a child with CF were significantly lower than they were for comparison families on overall family functioning and on four of the six MICS dimensions: communication, affect management, interpersonal involvement, and behavioral control. Moreover, a significantly greater percentage of families of children with CF were rated in the unhealthy range on overall family functioning and on five of six MICS dimensions. There was no relationship between family functioning and child weight status for children with CF. CONCLUSIONS: The current study suggests that for families of school-age children with CF, the family system is negatively affected during mealtime. Dietary interventions need to address family-centered, as well as child-centered, interventions to help families manage challenges presented during the family meal. 相似文献
45.
Chorioallantoic membrane angiogenesis model for tissue engineering: a new twist on a classic model 总被引:4,自引:0,他引:4
Tissue-engineering (TE) applications include the isolation, culture, and seeding of cells into a suitable matrix or scaffold before in vivo transplantation. After transplantation, vascularization of the scaffold is a principal limiting factor for cell viability for the first 6-8 days posttransplantation. A model for systematic analysis of this process has been developed. Fertilized White Leghorn eggs were incubated (at 37.8 degrees C in 60% relative humidity) and opened on day 3 of incubation. Preadipocyte-seeded fibrin constructs were implanted in a specially designed plastic cylinder and placed through the opening on the surface of the chorioallantoic membrane (CAM) on day 8 of incubation. Vascularization of the constructs by chorioallantoic blood vessels was assessed for up to 8 days posttransplantation. The survival rate for embryos receiving transplanted constructs was about 90%. Histology confirmed transplant cell viability at day 4 posttransplantation and vascularization of the constructs by avian endothelial cells began at this time. A new in vivo model to study the effect of angiogenesis in TE constructs, including assessments of viability, proliferation, and differentiation of transplanted cells and biomaterial properties, is presented. Advantages include easy access to the vascular network of the CAM, lack of immunocompetence, low costs, and avoidance of animal experiments. 相似文献
46.
Stark AR Carlo WA Tyson JE Papile LA Wright LL Shankaran S Donovan EF Oh W Bauer CR Saha S Poole WK Stoll BJ;National Institute of Child Health Human Development Neonatal Research Network 《The New England journal of medicine》2001,344(2):95-101
BACKGROUND: Early administration of high doses of dexamethasone may reduce the risk of chronic lung disease in premature infants but can cause complications. Whether moderate doses would be as effective but safer is not known. METHODS: We randomly assigned 220 infants with a birth weight of 501 to 1000 g who were treated with mechanical ventilation within 12 hours after birth to receive dexamethasone or placebo with either routine ventilatory support or permissive hypercapnia. The dexamethasone was administered within 24 hours after birth at a dose of 0.15 mg per kilogram of body weight per day for three days, followed by a tapering of the dose over a period of seven days. The primary outcome was death or chronic lung disease at 36 weeks' postmenstrual age. RESULTS: The relative risk of death or chronic lung disease in the dexamethasone-treated infants, as compared with those who received placebo, was 0.9 (95 percent confidence interval, 0.8 to 1.1). Since the effect of dexamethasone treatment did not vary according to the ventilatory approach, the two dexamethasone groups and the two placebo groups were combined. The infants in the dexamethasone group were less likely than those in the placebo group to be receiving oxygen supplementation 28 days after birth (P=0.004) or open-label dexamethasone (P=0.01), were more likely to have hypertension (P<0.001), and were more likely to be receiving insulin treatment for hyperglycemia (P=0.02). During the first 14 days, spontaneous gastrointestinal perforation occurred in a larger proportion of infants in the dexamethasone group (13 percent, vs. 4 percent in the placebo group; P=0.02). The dexamethasone-treated infants had a lower weight (P=0.02) and a smaller head circumference (P=0.04) at 36 weeks' postmenstrual age. CONCLUSIONS: In preterm infants, early administration of dexamethasone at a moderate dose has no effect on death or chronic lung disease and is associated with gastrointestinal perforation and decreased growth. 相似文献
47.
Reuvit Halperin Arie Herman Abraham Golan Eran Hadas David Schneider Ian Bukovsky Raphael Ron-El 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(2):102-105
PROBLEM: To examine the relationship between the concentration of uterine fluid human decidua-associated protein (hDP) 200, identified as a monoclonal rheumatoid factor, and different phases of the menstrual cycle. METHODS: Sequential measurements of hDP 200 concentration in uterine fluid were performed in 11 normal ovulatory women, aged 22–36 years. The samples were collected in early proliferative phase, late proliferative phase, periovulatory period, early secretory phase, and late secretory phase. RESULTS: Consistent fluctuations of hDP 200 levels in uterine fluid were found throughout the menstrual cycle. High levels were found during early proliferative phase and periovulatory period related to significantly lower levels during late proliferative and early luteal phases. CONCLUSION: There is menstrual phase dependent variation in the uterine fluid levels of hDP 200. 相似文献
48.
Group behavioral treatment of retentive encopresis 总被引:1,自引:0,他引:1
L J Stark J Owens-Stively A Spirito A Lewis D Guevremont 《Journal of pediatric psychology》1990,15(5):659-671
Investigated the efficacy of behavioral group treatment for children with retentive encopresis who had previously failed medical management. Eighteen children between the ages of 4 and 11 years and their parents were seen in small treatment groups of 3 to 5 families over 6 sessions. The sessions focused on education about retentive encopresis, and the integration of behavioral parenting procedures with medical management. Parents and children were taught to deliver an enema clean-out, increase the children's dietary fiber, and appropriate toileting techniques. The results indicated that children significantly increased their fiber consumption by 40%, increased appropriate toileting by 116%, and decreased their soiling accidents by 83% pre- to posttreatment. Further, these treatment gains maintained or improved at the 6-month follow-up. The results are discussed in terms of cost-effective interventions and the interface between psychology and medicine in pediatric psychology. 相似文献
49.
50.
A behavioral approach to increasing calorie consumption in children with cystic fibrosis 总被引:1,自引:1,他引:1
To increase calorie consumption of 5 mildly malnourished children with cystic fibrosis (CF), intervention was implemented in multiple baseline fashion across snack and three meals. Intervention involved nutritional education establishing gradually increasing calories goals, teaching parents contingency management strategies, and a reward system for achieving calorie goals. Following 6 treatment sessions, the children's calorie intake increased across meals and total calorie intake was 25 to 43% above baseline. The calorie increase was maintained at 9-month follow-up. Significant changes in weight and height were made during treatment and the year following intervention. The results suggest that the long-term oral intake of children with CF can be modified by a short-term behavioral intervention. 相似文献