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61.
Growth hormone effects on hypertrophic scar formation: a randomized controlled trial of 62 burned children 总被引:3,自引:0,他引:3
Gisele V. de Oliveira MD ; Arthur P. Sanford MD ; Kevin D. Murphy MD ; Hermes M. de Oliveira MD ; Judy P. Wilkins RGN ; Xiaowu Wu MD ; Hal K. Hawkins MD PhD ; Gregory Kitten PhD ; David L. Chinkes PhD ; Robert E. Barrow PhD ; David N. Herndon MD 《Wound repair and regeneration》2004,12(4):404-411
The hypercatabolism after massive pediatric burns has been effectively treated with recombinant human growth hormone, an anabolic agent that stimulates protein synthesis and abrogates growth arrest. While experimental studies have shown increased potential for fibrosis induced by growth hormone therapy, adverse effects on human scars have not been investigated. Our aim was to evaluate hypertrophic scar formation in 62 patients randomized to receive injections of 0.05 mg/kg/day of recombinant human growth hormone or placebo, from discharge until 1 year after burn. Scar scales were used to evaluate scar-severity at discharge, 6, 9, 12, and 18-24 months after burn, by three observers blinded to treatment. Computer-assisted planimetry allowed quantification of percentage of hypertrophic scar formation. Types I and III collagens were localized and quantified in scars and normal skin of patients from both groups, using immunohistochemistry with confocal laser microscopy analysis. Insulin-like growth factor-1 blood levels helped assess compliance. Statistical analysis showed that scar hypertrophy significantly increased from 6 to 12 months after injury in both groups, while decreasing at 18-24 months postburn. Types I and III collagens were statistically increased in the reticular layer of scars from both groups when compared to paired normal skin. Insulin-like growth factor-1 was significantly increased in the recombinant human growth factor-treated group. No differences were seen when recombinant human growth factor and control groups were compared using the scar scales, planimetry, or immunohistochemistry. We concluded that recombinant human growth hormone therapy did not adversely affect scar formation and should not contraindicate the administration of recombinant human growth hormone as a therapeutic approach to severely burned children. 相似文献
62.
Ng Esther; Leader Arthur; Claman Paul; Domingo Minerva; Spence John E.H. 《Human reproduction (Oxford, England)》1995,10(4):807-810
A cohort study was undertaken to compare the effect at the timeof oocyte retrieval of the i.v. administration of either 1000ml of lactated Ringer' solution or 1000 ml of a 5% solutionof human albumin on in-vitro fertilization patients at riskfor severe ovarian hyperstimulation syndrome (OHSS). A totalof 207 patients with an oestradiol concentration > 10 000pmol/l and/or > 15 follicles (>10 mm diameter) on theday of human chorionic gonadotrophin (HCG) injection were reviewed.Of these, 158 women received 500 ml of lactated Ringerssolution both before and after egg retrieval, and 49 women receivedtwo infusions of 500 ml of 5% human albumin in normal salineat the time of egg retrieval. Severe OHSS developed in two patientswho received human albumin and in 10 women who did not receivethe albumin. This difference was not statistically significant.There were no differences between the two groups in terms ofage, number of follicles punctured at transvaginal oocyte retrievalor oestradiol concentration at the time of HCG injection. Theadministration of a 5% human albumin solution does not preventthe development of severe OHSS in at risk patients. It doesappear to blunt the severity of the condition. 相似文献
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The January 7, 1988 issue of The New England Journal of Medicine has two interesting articles concerning what might generally be termed euthanasia. The article titled Initiating and Withdrawing Life Support represents a consensus among members of the Stanford University Medical Center Committee on Ethics. Its main authors have written a fine example of applied ethics (1). 相似文献
66.
Chest radiographs and chest computed tomography (CT) scans were compared in 203 patients with newly diagnosed Hodgkin disease. The incidence of positive findings was tabulated from six intrathoracic lymph node groups, lung parenchyma, pericardium, pleura, and chest wall. The discordant cases were assessed to determine impact on clinical management. The CT scans provided additional evidence of disease involvement, ranging from 0% to 15% at each of the designated anatomic sites. Treatment was altered in 9.4% of all patients (19 of 203), including 13.8% (nine of 65) of those undergoing radiation therapy alone and 8.2% (ten of 122) of those undergoing combined-modality treatment. We conclude that routine chest CT examinations are valuable in the clinical management of those patients for whom radiation therapy is planned. 相似文献
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PURPOSE: To examine the relationship between ametropia and optical aberrations in a population of 200 normal human eyes with refractive errors spanning the range from +5.00 to -10.00 D. METHODS: Using a reduced-eye model of ametropia, we tested the hypothesis that the optical system of the eye is uncorrelated with the degree of ametropia. These predictions were evaluated experimentally with a Shack-Hartmann aberrometer that measured the monochromatic aberrations across the central 6 mm of the dilated pupil in well-corrected, cyclopleged eyes. RESULTS: Optical theory predicted, and control experiments on a model eye verified, that Shack-Hartmann measurements of spherical aberration will vary with axial elongation of the eye even if the dioptric components of the eye are fixed. Contrary to these predictions, spherical aberration was not significantly different from emmetropic eyes. Root mean square of third-order aberrations, fourth-order aberrations, and total higher aberrations (third to 10th) in myopic and hyperopic eyes were also uncorrelated with refractive error. Astigmatic eyes tended to have larger total higher-order aberrations than nonastigmatic eyes. CONCLUSIONS: We conclude that a reduced-eye model of myopia assuming fixed optical parameters and variable axial length is not tenable. 相似文献
69.
Xin Hong Larry N Thibos Arthur Bradley Russell L Woods Raymond A Applegate 《Optometry and vision science》2003,80(1):15-25
Repeated measures of wavefront aberrations were taken along the line-of-sight of seven eyes using two instruments: an objective, cross-cylinder aberroscope (OA) and a Shack-Hartmann (SH) aberrometer. Both instruments were implemented on the same optical table to facilitate interleaved measurements on the same eyes under similar experimental conditions. Variability of repeated measures of individual coefficients tended to be much greater for OA data than for SH data. Although Zernike coefficients obtained from a single measurement were generally larger when measured with the OA than with the SH, the averages across five trials were often smaller for the OA. The Zernike coefficients obtained from the two instruments were not significantly correlated. Radial modulation-transfer functions and point-spread functions derived from the two sets of measurements were similar for some subjects, but not all. When average Zernike coefficients were used to determine optical quality, the OA indicated superior optics in some eyes, but the reverse trend was true if Zernike coefficients from individual trials were used. Possible reasons for discrepancies between the OA and SH measurements include difference in sampling density, quality of data images, alignment errors, and temporal fluctuations. Multivariate statistical analysis indicated that the SH aberrometer discriminated between subjects much better than did the objective aberroscope. 相似文献
70.
C A Blank J E Nagel W H Adler F J Heldrich 《Maryland medical journal (Baltimore, Md. : 1985)》1989,38(9):739-742
A varicella infection in a previously healthy young girl was complicated by bacterial sepsis, arthritis, and osteomyelitis in multiple locations. This secondary complication caused by Staphylococcus aureus was associated with a transient defect in granulocyte function and an alteration in the representation of CD4 and CD8 positive lymphocyte subpopulation. The mechanism responsible for secondary bacterial infections following varicella may be due to transient defects in granulocyte function. 相似文献