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941.
F Hammarqvist B Westman CE Leijonmarck K Andersson J Wernerman 《Canadian Metallurgical Quarterly》1996,119(4):417-423
A number of studies have localized CGRP to nerves in the cornea and iris, and it is thought that CGRP, along with other neuropeptides, is involved in pain sensation. It is also possible that CGRP could mediate trophic influences between nerve endings and corneal epithelium. This investigation utilized an in vitro rabbit corneal whole mount preparation to study the effect of topical 2.5 microM CGRP application on epithelial wound healing rates of 5 mm diameter epithelial wounds. CGRP (2.5 microM) was applied topically to 5 mm epithelial wounds at 0, 4, 16, 20, 24, 28, 40, 44, 48, 52, 56, 64, 68, and 72 hours after wounding and healing was visualized with fluorescein. CGRP was found to increase the epithelial wound healing rate by 25%, from 51 +/- 3 microns/hr for the control corneas, to 64 +/- 2 microns/hr for CGRP-treated corneas (mean +/- standard error, n = 10). Histological examination of the corneas following healing showed that the epithelium of the CGRP-treated corneas healed in a similar manner as in the control corneas. These findings may have clinical utility for the understanding and treatment of corneal and other epithelial wounds. 相似文献
942.
943.
I F?rster 《Canadian Metallurgical Quarterly》1998,6(1-2):89-94
We have used a plasmid containing the argB gene to transform an Aspergillus nidulans argB-deleted strain in the presence of restriction enzymes and show a 20- to 60-fold increase in transformation frequency via restriction enzyme-mediated integration (REMI). This procedure was used to try to tag new genes involved in the asexual development of this fungus. More than 2000 transformants isolated following electroporation of conidia and approximately 3700 transformants recovered following protoplast fusion were screened for sporulation defects. Unexpectedly, developmental mutants were obtained only when the protoplast fusion approach was used. Southern blot analysis of these mutants, and of randomly selected transformants obtained by electroporation, was consistent with the occurrence of single plasmid integration events in 33 and 65% of the cases, respectively. The argB marker was shown to be tightly linked to the mutant phenotype in only 62% of the mutants analyzed by sexual crosses. Partial DNA sequencing of a tagged gene, whose mutation delays asexual sporulation and results in a fluffy phenotype, showed no homology to previously reported sequences. Our results indicate that REMI can be used in A. nidulans to increase the transformation frequency and illustrate the advantages and potential problems when using REMI to tag genes of interest in this and other fungi. 相似文献
944.
A series of 7-deazapurine 2'-deoxyribofuranosides were synthesized according to already known procedures and their substrate and inhibitor properties with purified E. coli purine nucleoside phosphorylase were examined. In agreement with previous findings, substrate activity was not detected for any of the compounds tested. Most of the nucleosides showed weak inhibition in the preliminary screening, i.e. at a concentration of about 100 microM. However some combinations of 6-chloro, 6-amino or 6-methoxy substituents with bulky hydrophobic groups at position 7 of the base and/or chloro, amino, methoxy or methylthio group at position 2 markedly enhanced affinity of such modified nucleosides for the E. coli enzyme. The most potent inhibition was observed for two nucleosides: 6-chloro- and 2-amino-6-chloro-7-deazapurine 2'-deoxyribofuranosides that show inhibition constants Ki = 2.4 and 2.3 microM, respectively. Several other compounds were also found to be good inhibitors, with inhibition constants in the range 5-50 microM. In all instances the inhibition was competitive vs. the nucleoside substrate 7-methylguanosine. Inhibition constants for 7-deazapurine nucleosides are in general several-fold lower than those observed for their purine counterparts. Therefore 7-deaza modification together with substitutions at positions 2, 6 and 7 of the base is a very promising approach to obtain competitive noncleavable inhibitors of E. coli PNP that may bind to the enzyme with inhibition constants in the microM range. 相似文献
945.
946.
The psychologist interested in expanding or diversifying practice will find the relatively new field of applied sport psychology rich in opportunities for learning, collaboration, and development. Exercise can be an important adjunct to psychotherapy, and psychological skills training offers systematic methods for performance improvement. Sport psychology is derived from a blending of sport science and psychology, and practitioner psychologists bring unique skills to this domain. Building on already developed areas of expertise, the psychologist can apply new skills to different populations in diverse settings. At the same time, the practitioner with an interest in sport psychology should obtain sufficient training, consider credentialing, and recognize ethical issues particular to this field. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
947.
Luis Armando Rosas Rivera Norma F. Hubele PhD Frederick P. Lawrence PhD 《Computers & Industrial Engineering》1995,29(1-4):55-58
Process capability indices (PCIs) are used in industry to assess percentages of nonconforming parts. An underlying assumption is that the output process measurements are distributed as normal random variables. When normal distributions are assumed, but different distributions are present - such as skew, heavy-tailed, and short-tailed distributions - the percentages of nonconforming parts are significantly different than the computed PCIs indicate. Data arising from nonnormal distributions can sometimes be transformed to conform to the normality assumption and the PCI's computed for the transformed data. In this paper, the effect of the transformation on the estimate of nonconforming parts is examined for three examples of nonnormal distributions - gamma, lognormal, and Weibull. The results of this experimental analysis suggest that data transformation can be useful for estimating an interval for Cpk values and the number of nonconforming parts. 相似文献
948.
M Degiuli T Allone A Pezzana D Sommacale P Gaglia F Calvo 《Canadian Metallurgical Quarterly》1996,51(5):255-264
The relations between incidence and prognosis of postoperative fistulas after gastrectomy and some different variables were analysed in the present retrospective study. Thirteen digestive fistulas of 113 patients (11.9%) submitted to gastrectomy during the period 1989-1994 represent the study population. The incidence of postoperative fistulas was compared to the kind of gastric pathology, to the extension of gastrectomy, to different nutritional (serum haemoglobin, albumin and transferrin level, weight loss) and immunological factors (serum lymphocytes) and, for oncological patients, to the stage of the disease. Incidence was directly related to the extension of gastrectomy, to serum albumin and haemoglobin level, and to weight loss rate. The results were not statistically significant at Kruskal-Wallis and ANOVA tests. No relation was found between incidence of fistulas and serum transferrin level, number of lymphocytes and adoption of early postoperative enteral nutrition. Six patients had spontaneous closure of the fistula with conservative therapy. Seven patients required reoperation because of abdominal sepsis (53.8%). Three patients died (23%). Although spontaneous closure, reoperation and mortality were related to nutritional and immunological state, no examined variables showed a statistically significative relation. The adoption of early postoperative enteral nutrition was not related to the prognosis, unlike the stage of the disease: patients submitted to reoperation had a TNM III or IV stage; dead patients had a TNM IV stage. Treatment of metabolic-nutritional unbalance can prevent anastomotic failure and fistula after gastrectomy and improve the prognosis. The relation between early postoperative enteral nutrition and incidence and prognosis of postoperative fistulas remains unclear. 相似文献
949.
950.
PURPOSE: The present study evaluated the expression of alpha1-adrenoceptor subtypes in human corpus cavernosum. MATERIALS AND METHODS: The mRNA encoding alpha1a, alpha1b and alpha1d subtypes were assessed by RNA-directed complementary cDNA synthesis followed by Taq DNA amplification. The level of alpha1 mRNA was calculated in arbitrary optical density units and normalized with respect to the length of the respective cDNA fragments. RESULTS: We found that alpha1a, alpha1b and alpha1d adrenoceptor subtypes are expressed in human corpus cavernosum, with a predominant expression of the alpha1a subtype. CONCLUSION: These results suggest that alpha1a-adrenoceptor subtype is important and that understanding the biochemical and functional characteristics of this subtype may lead to the development of specific antagonists in the treatment of impotence. 相似文献