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131.
C Llado Carbonell O Arango Toro J Vesa Llanes O Bielsa Gali A Gelabert Mas 《Canadian Metallurgical Quarterly》1996,6(2):292-296
Initially thought to act as tissue replacement, cultured epithelial allografts are now known to work by providing a potent stimulus for healing. In a similar fashion, we believe that traditional autografts may also provide a stimulus to help heal chronic wounds, thus acting as pharmacological agents for healing. We attempted to assess the possibility of augmenting the stimulatory properties of donor skin by initiating the healing process in the donor region prior to grafting. This was accomplished by pre-wounding the donor area 3 days prior to harvesting the donor skin. We compared these 'pre-wounded' grafts to those harvested immediately. Two patients underwent punch grafting for chronic leg ulceration. Half of the ulcer was grafted with donor skin harvested from an area that was pre-wounded and the other half from freshly harvested skin. We evaluated each for improvement of granulation tissue and degree of edge effect (migration of the previously dormant wound edges). All the grafts did well. There was marked improvement in granulation tissue in the ulcer bed after grafting, and the obvious presence of an edge effect. The edge effect was increased on the site where the pre-wounded grafts were placed. It may be possible to augment the growth stimulatory properties of donor skin. This may offer therapeutic options in patients with chronic wounds. 相似文献
132.
Galavotti Christine; Saltzman Linda E.; Sauter Steven L.; Sumartojo Esther 《Canadian Metallurgical Quarterly》1997,52(2):154
Behavioral research and surveillance activities are conducted across the Centers for Disease Control and Prevention (CDC). This article highlights activities in 4 program areas: violence against women, tuberculosis elimination, HIV prevention, and occupational health. The unique constraints and opportunities of each organization and program focus have shaped the way research has developed in each of these areas. Behavioral scientists also face many common challenges at CDC. Despite the difficulties of integrating behavioral research into an institution that historically has focused on biomedical and epidemiological research, behavioral scientists have made important contributions to public health. Many opportunities remain for psychologists to translate theory and operationalize constructs for use in solving important public health problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
133.
Abstract. This paper analyses how outliers affect the identification of conditional heteroscedasticity and the estimation of generalized autoregressive conditionally heteroscedastic (GARCH) models. First, we derive the asymptotic biases of the sample autocorrelations of squared observations generated by stationary processes and show that the properties of some conditional homoscedasticity tests can be distorted. Second, we obtain the asymptotic and finite sample biases of the ordinary least squares (OLS) estimator of ARCH(p) models. The finite sample results are extended to generalized least squares (GLS), maximum likelihood (ML) and quasi‐maximum likelihood (QML) estimators of ARCH(p) and GARCH(1,1) models. Finally, we show that the estimated asymptotic standard deviations are biased estimates of the sample standard deviations. 相似文献
134.
Describes 3 relatively simple computer algorithms for estimating the average number of syllables/word in text from letter counts. The syllable counts were used to determine Flesch Reading Ease Scores for text by computer. Vowel counts worked well. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
136.
Juan Parrado Esther MiramontesMaria Jover Juan Fco GutierrezLaura Collantes de Terán Juan Bautista 《Food chemistry》2006,98(4):742-748
The production, stabilization, by enzymatic treatment, physicochemical composition, and biological properties (including the anti-proliferative activity), of a water-soluble rice bran enzymatic extract (RBEE) are described. The main component of RBEE is proteins (38.1%) – in the form of peptide and free amino acids – having a 6% content of sulfur amino acids. The second component is fat (30.0%), with oleic and linoleic acids as the major components, and 1.2 mg/g of γ-oryzanol. Carbohydrates (14.2%) are comprised mainly of slowly absorbed carbohydrates. Preliminary studies on the anti-proliferative effect of RBEE on leukemia tumor cell growth in vitro are also reported. This property makes RBEE potentially useful as a functional food for the treatment and prevention of chronic pathological states associated with abnormal proliferation of cells, as is the case with cancer. 相似文献
137.
Tested the hypothesis that task variables account for previous findings that reading rate is unaffected by readability. In a study with 68 high school students, variations in a reading task were used to induce different processes during reading. When the S had to inspect a text to remember enough for a subsequent word match, easy texts were read faster than difficult texts. When word matching was attempted as the S read, easy texts were read no faster than difficult texts. Findings suggest that when appropriate reading tasks are chosen, reading rate can be used to infer underlying processes in reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
JM Bermúdez de Castro JL Arsuaga E Carbonell A Rosas I Martínez M Mosquera 《Canadian Metallurgical Quarterly》1997,276(5317):1392-1395
Human fossil remains recovered from the TD6 level (Aurora stratum) of the lower Pleistocene cave site of Gran Dolina, Sierra de Atapuerca, Spain, exhibit a unique combination of cranial, mandibular, and dental traits and are suggested as a new species of Homo-H. antecessor sp. nov. The fully modern midfacial morphology of the fossils antedates other evidence of this feature by about 650, 000 years. The midfacial and subnasal morphology of modern humans may be a retention of a juvenile pattern that was not yet present in H. ergaster. Homo antecessor may represent the last common ancestor for Neandertals and modern humans. 相似文献
139.
The dispersion of a pulse of solute in a capillary tube undergoing irreversible, heterogeneous reaction or reversible adsorption at the tube wall is considered in order to test certain concepts regarding the construction of dispersion equations. To compare theory and experiment, computer experiments have been performed which indicate that the time dependence of the coefficients in a general dispersion equation may be quite complex. For sufficiently long times the computer experiments provide confirmation of the well-established Taylor-Aris result in addition to providing the first experimental proof of the Golay theory for reversible adsorption. 相似文献
140.
A Hernándiz Martínez V Pallarés Carratalá J Cosín Aguilar F Andrés Conejos C Capdevila Carbonell M Portolés Sanz 《Canadian Metallurgical Quarterly》1997,50(9):650-657
INTRODUCTION AND OBJECTIVES: Myocardial ATP is produced mainly by fatty acid oxidation, a process in which the fatty acid metabolite carrier carnitine is needed to carry the metabolites into the mitochondria. Cardiac ischemia is associated with carnitine depletion. Our objective was to study the functional effect of L-carnitine on myocardium stunned by very brief, repeated ischemias, and to examine its actions in the recovery period. METHODS: The two series studied were the control series (7 dogs) and the carnitine series (7 dogs). L-carnitine was administered to the carnitine series at doses of 250 mg/kg/day starting 7 days before the ischemic protocol and continuing during the follow-up period (10 and 15 days). The ischemic protocol consisted of 20 anterior descending coronary artery occlusions lasting 2 min and with 3 min of reperfusion between occlusions. Global and regional cardiac function parameters were recorded daily. RESULTS: No differences in the global functional (haemodynamic) or ECG of the two series were found, but there were differences in regional myocardial function. The control series segment shortening fraction fell to dyskinesis values during the occlusion periods, then recovered during reperfusions. The segment shortening fraction worsened during the stunning period, reaching its maximal impairment on the 5th day, after which it returned to basal values on the 15th day. The carnitine series showed the same performance in the occlusion/reperfusion period. However, during the stunning period the segment shortening fraction recovered and reached values close to the basal ones maintained them during the follow-up period. CONCLUSIONS: L-carnitine induces an almost immediate recovery of myocardial contractility, when it has been affected by very brief, repeated coronary occlusions. It limits the myocardial stunning apparition. 相似文献