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This investigation was designed to test the hypothesis that alterations in small-bowel motility are associated with total parenteral nutrition (TPN). Motility, as reflected by intestinal transit, was studied in rats maintained by TPN for 7–10 days and compared to that of rats fed an oral diet isocaloric with the intravenously administered solution. Transit was measured by injecting radioactively labeled chromium (Na2 51CrO4) into the duodenum via permanently implanted catheters. Fifteen minutes after injection of the label, animals were killed and the linear distribution of the isotope in the gut was determined. The leading edge of radioactivity traversed 75–87% (95% confidence limit) of the gut length in enterally fed rats and 83–97% in rats on TPN. The difference between the average position of these fronts for the two groups was not statistically significant (P>0.05). In addition, the regression of percent radioactivity traversing or present in a given segment on gut length yielded a slope with 95% confidence limits of –10.48 to –15.02 for orally fed control rats and –9.83 to –12.87 for rats on TPN. Differences between these slopes were not statistically significant (P>0.05). Results support the conclusion that factors which regulate small-bowel motility are not altered significantly by TPN during the time that other functional and structural changes reportedly occur.This study was supported by NIH Grants AM 18164, AI 11361, AM 16305. Dr. Castro is the recipient of NIH Research Career Development Award AI 00087. Dr. Weisbrodt is the recipient of PHS Research Scientist Development Award DA 00022.  相似文献   
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In this paper, we present evidence on the health effects of a health insurance intervention targeted to poor children using data from a randomized policy experiment known as the Quality Improvement Demonstration Study. Among study participants, using a difference‐in‐difference regression model, we estimated a 9–12 and 4–9 percentage point reduction in the likelihood of wasting and having an infection, respectively, as measured by a common biomarker C‐reactive Protein. Interestingly, these benefits were not apparent at the time of discharge; the beneficial health effects were manifest several weeks after release from the hospital. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Peptic and/or duodenal ulcers are characterized by diverse acute and chronic ulcerative lesions that commonly arise in any portion of the gastric mucosa that is exposed to the aggressive action of gastric acid. The pathophysiology of peptic ulcers has been attributed to an imbalance between aggressive and protective factors. In Brazil, medicinal plants are commonly used to treat this ailment. A country with great biodiversity, Brazil is considered a rich source of therapeutic products. There have been popular and pharmacological reports on the medicinal relevance of the Brazilian cerrado plant species, including Ananas ananassoides, Celtis iguanaea, Encholirium spectabile, Hymenaea stigonocarpa, Lafoensia pacari, Qualea grandiflora, Qualea parvifora, Mouriri pusa, Solanum lycocarpum, Solanum paniculatum, Serjania erecta, and Vochysia tucanorum, in the treatment of stomach disorders. The aim of the present review was to report on some of the Brazilian cerrado plants that are used in folk medicine because of their gastroprotective potential and to encourage novel studies in the search and preservation of plants with this therapeutic potential.  相似文献   
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Onion-like graphitic structures are of great importance in different fields. Pentagons, heptagons, and octagons are essential features of onion-like graphitic structures that could generate important properties for diverse applications such as anodes in Li metal batteries or the oxygen reduction reaction. These carbon nanomaterials are fullerenes organized in a nested fashion. In this work, we produced graphitic nano onion-like structures containing phosphorus and nitrogen (NP-GNOs), using the aerosol assisted chemical vapor deposition method. The NP-GNOs were grown at high temperature (1020 °C) using ferrocene, trioctylphosphine oxide, benzylamine, and tetrahydrofuran precursors. The morphology, structure, composition, and surface chemistry of NP-GNOs were characterized using different techniques. The NP-GNOs showed diameters of 110–780 nm with Fe-based nanoparticles inside. Thermogravimetric analysis showed that NP-GNOs are thermally stable with an oxidation temperature of 724 °C. The surface chemistry analysis by FTIR and XPS revealed phosphorus–nitrogen codoping, and several functionalities containing C–H, N–H, P–H, P–O, P Created by potrace 1.16, written by Peter Selinger 2001-2019 O, C Created by potrace 1.16, written by Peter Selinger 2001-2019 O, and C–O bonds. We show density functional theory calculations of phosphorus–nitrogen doping and functionalized C240 fullerenes. We present the optimized structures, electronic density of states, HOMO, and LUMO wave functions for P-doped and OH-functionalized fullerenes. The P Created by potrace 1.16, written by Peter Selinger 2001-2019 O and P–O bonds attributed to phosphates or hydroxyl groups attached to phosphorus atoms doping the NP-GNOs could be useful in improving supercapacitor function.

Nitrogen–phosphorus doped graphitic nano onion-like structures.  相似文献   
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