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31.
S C Chua A W Brown J Kim K L Hennessey R L Leibel J Hirsch 《Brain research. Molecular brain research》1991,11(3-4):291-299
We have used a novel method to identify genes expressed in the hypothalamus which may be potentially involved in controlling food intake and energy metabolism. We assumed that food deprivation, a powerful stimulus of food intake, would stimulate the activity of neural pathways involved in feeding behavior which should be reflected in an increase in the synthesis of any relevant neuropeptide and its messenger RNA. A study of 5 neuropeptides in 5 strains of mice has identified neuropeptide Y (NPY) as a gene whose expression in the hypothalamus is controlled by nutritional status, suggesting that hypothalamic NPY neurons are a link in the neural network regulating feeding behavior and energy metabolism. In addition, we have studied the effect of the diabetes mutation on neuropeptide gene expression during fasting and refeeding. Our findings suggest that abnormal NPY and enkephalin gene expression in the hypothalamus may be two important determinants of the expression of the diabetes mutation. 相似文献
32.
Angiogenesis induction and regression in human surgical wounds 总被引:2,自引:0,他引:2
Nicola J. Brown PhD ; Edward A. E. Smyth Bmedsci ; Simon S. Cross MD ; Malcolm W. R. Reed MD 《Wound repair and regeneration》2002,10(4):245-251
Angiogenesis in human wound healing is not well characterized, with only sparse information available regarding the maturation and fate of vessels formed as a consequence of human tissue repair. Therefore, this study aimed to establish the temporal profile of angiogenesis in human dermal wounds. Punch biopsies were obtained under local anesthesia from 45 patients following breast surgery. Scars were predominantly between 2 and 52 weeks after surgery but in five patients were > 52 weeks. Control samples were taken from breast skin peroperatively (n = 24). Quantification of vascular density was performed using the Chalkley grid, following antibody staining for platelet endothelial cell adhesion molecule. Vascular patterns, wound cellularity and morphology were also determined. Cumulative microvessel density was increased in all samples when compared to controls (p < 0.05). This was greatest 2 to 24 weeks following surgery 17 (15-21) median (range), decreased thereafter, but remained elevated compared to controls even in the mature scars > 52 weeks. Control tissue showed an ordered morphological arrangement of dermal structures, collagen, and elastic fibers. However, wounding resulted in marked structural distortion for up to 15 weeks. In conclusion, this study shows for the first time the prolonged persistence of both microvessels and cellularity (fibroblastic cells), in addition to structural distortion in human dermal wounds, which is in contrast to previous in vitro and in vivo studies. 相似文献
33.
Power density producing damage at a probability of 0.5 (ie, damage threshold, DT-50) was determined for PMMA (with/without UV absorber) and Silicone intraocular lenses. Scattered light from a collinear diagnostic He:Ne beam was one of four damage monitors deployed to enhance the sensitivity of the system. In order of increasing laser resistance the following results were obtained: injection molded PMMA (1.9/GW/cm2) Silicone (2.63 GW/cm2) Lathe-cut PMMA (4.47 GW/cm2), Lathe-cut PMMA with UV absorber (8.32 GW/cm2), Cast-molded PMMA (12.30 GW/cm2). An analysis of variance revealed interclass differences significant at the .01 level. Cast-molded PMMA was the most laser-resistant IOL material. 相似文献
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To measure intestinal absorption by using a single, random stool sample, polyethylene glycol (PEG), 1 g/d, and a constant diet were given to healthy infants, with a constant PEG-to-macronutrient ratio. After 10 d equilibration, apparent intestinal absorption of macronutrients was estimated from a standard 3-d metabolic balance and compared with that estimated by using the ratio of PEG to macronutrients in a single random sample of feces. Correlation coefficients for this comparison were 0.649, 0.715, and 0.924 for nitrogen, carbohydrate, and fat, respectively. Additionally, apparent intestinal absorptions estimated from two separate consecutive 3-d metabolic-balance studies were compared, showing correlation coefficients of 0.106, 0.653, and 0.463 for nitrogen, carbohydrate, and fat, respectively. The random sample-marker technique appears to be acceptable for measuring apparent absorption of macronutrients and is at least as accurate as a standard 3-d metabolic-balance study. 相似文献
39.
Quantitative studies of morbidity, food intake, and somatic growth were done prospectively during 14 mo for 70 children aged 5-18 mo in two Bangladeshi villages. When random-effect regression models were used, monthly changes in weight were inversely related to proportions of days in the month with fever and diarrhea and positively related to energy intake per kilogram body weight. Interestingly, weight changes did not vary with age in this interval. Estimates indicate that increasing energy intakes to the recommended World Health Organization level would have a significantly greater effect on weight gain than would the elimination of diarrhea and fever. With energy at recommended intake and diarrhea and fever prevalence as found in US children, weight gain is predicted to be near that of the international reference population. Therefore, interventions aimed at improving dietary intake may be as important as infection-control programs for improving growth of children in poor developing nations. 相似文献
40.
Potential aripiprazole-mediated extrapyramidal symptoms in an adult with developmental disabilities.
Nancy C Brahm David L McElwain Robert C Brown 《American journal of health-system pharmacy》2007,64(8):827-829
PURPOSE: A case of extrapyramidal symptoms (EPS) following administration of aripiprazole to a man with developmental disabilities who had never received antipsychotic medications and had no history of movement disorders is presented. SUMMARY: The patient was a 40-year-old male with developmental disabilities. He was nonverbal, profoundly mentally retarded, and diagnosed with obsessive compulsive disorder (OCD) and orthopedic problems. He developed episodic movements possibly consistent with EPS secondary to aripiprazole usage. The patient was antipsychotic naive before initiation of aripiprazole 5 mg daily. Concurrent medications at the time of EPS onset included oxazepam, baclofen, and citalopram. Baclofen and oxazepam were prescribed secondary to right-sided hemiparesis contractures. Aripiprazole, 5 mg daily, was initiated in November 2004 as an augmentation strategy for the diagnosis of OCD. Facial, tongue, and arm movements were first reported approximately five weeks after the initiation of aripiprazole. Initial symptoms resolved after approximately 24 hours. The dosage was increased to 10 mg daily two weeks later. Dystonic episodes continued on an intermittent basis, and the patient presented with lower-lip thrusting and upper-limb athetosis. These movements interfered with the patient's eating, chewing, and holding of utensils. Several of the standard treatment strategies for EPS were used. Initially, diphenhydramine hydrochloride 25 mg was administered orally every six hours. The patient's movements resolved following diphenhydramine administration. Aripiprazole was subsequently discontinued secondary to its lack of efficacy for OCD and the development of a movement disorder. CONCLUSION: A patient with developmental disabilities who had no history of movement disorders developed EPS following initiation of aripiprazole. 相似文献