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21.
The influence of fibrin glue on adhesion formation and peritoneal healing is evaluated in a prospective, randomized, controlled study. In all, 20 Wistar rats underwent microsurgical suturing of two silicone sheets, one covered with a fibrin glue barrier, to the anterior peritoneum. Each animal thus served as its own control. After 10 days, adhesions and peritoneal healing were evaluated by a blinded observer through a second-look laparotomy. Adhesions were scored using a modification of the classification of Diamond. Tissue around the silicone sheet was examined histologically and by scanning electron microscopy to evaluate the inflammatory reaction and peritoneal healing (ingrowth of blood vessels and quality of peritoneal cells). Adhesion scores for treated and control sides were (mean +/- SD) 2.89 +/- 4.68 and 6.79 +/- 9.09 (P = 0.181) respectively, and the percentage of the sheet covered by peritoneum was 26.25 +/- 31.50 and 29.21 +/- 40.21 (P = 0.226) respectively. Using the paired Wilcoxon rank test, the P values for the ingrowth of blood vessels and peritoneal healing evaluated by histology and scanning electron microscopy were 0.842, 0.692 and 0.695 respectively. We conclude that although the mean adhesion score was reduced by > 50% by fibrin glue, there is no statistically significant difference concerning adhesion formation or peritoneal healing with the use of fibrin glue. 相似文献
22.
Button Cathryn M.; Grant Malcolm J.; Hannah T. Edward; Ross Abraham S. 《Canadian Metallurgical Quarterly》1993,25(2):230
Two studies identified and labeled the dimensions that people use to judge others' attitudes. In the 1st study, 50 male and 50 female undergraduates viewed pairs of attitude statements drawn from 1 or 2 large sets. For each pair of statements, Ss judged whether or not a person who agreed with one statement in the pair would be likely to agree with the other. The dimensions of liberalism and traditional values were found to underlie perceived attitudes. Validity was confirmed in a 2nd study with 60 male and 60 female undergraduates who rated the characteristics of hypothetical people who agreed strongly with particular statements. Results suggest that there is a common structure to people's perceptions of others' attitudes. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Flory–Huggins interaction parameters, λ, were determined for a series of probes in an amine cured epoxy resin matrix (433–493 K) and its precursors (324–363 K) by inverse gas chromatography (IGC). Hildebrand–Scatchard theory was combined with Flory–Huggins theory in order to estimate infinte dilution solubility parameters (δ2) for the matrix and its precursors at 298 K. It was shown that the value of the solubility parameter for the cured resin matrix lies between those of its precursors. Compared to the majority of published work, an unusual aspect of this application of IGC is that solubility parameters have been determined when the stationery phases are (i) small molecules and (ii) a highly crosslinked polymer. Moreover, all possible attempts have been made to ensure equilibrium conditions between probe and stationary phase, and compensation for asymmetry of peak profile has been applied in determining δ2. The solubility parameters estimated by IGC are in good agreement with those calculated by other methods. 相似文献
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Magnetorheological materials have been used in many applications in recent years. To develop new materials, polyurethane and silicone polymer gels were investigated. Rheology is qualitatively controlled for each system by controlling the concentration of reactants and diluents. The resulting polymers have solid, gel, or liquid states, depending on the crosslinking and dilution. The gels were characterized through kinetic analysis. Differential scanning calorimetry (DSC) was used with analysis methods to find the kinetic properties for diluted and undiluted polyurethane systems. Heat of reaction, order of reaction, preexponential constant, and activation energy were obtained from the experimental DSC data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2733–2742, 2002 相似文献
26.
IA Likhtarev GM Gulko IA Kairo K Henrichs HG Paretzke 《Canadian Metallurgical Quarterly》1994,66(2):137-146
In the context of the radiation exposure of the Ukrainian population resulting from the Chernobyl accident, the quantification of the thyroid doses due to iodine incorporation is of special interest. This first part of a series of planned publications deals with the dose and risk estimation for Kiev citizens. Although these doses are expected to be considerably lower than those for some other regions of Ukraine, the investigations started with this population because the quantification of the thyroid doses due to iodine incorporation is of special interest. This first part of a series of planned publications deals with the dose and risk estimation for Kiev citizens. Although these doses are expected to be considerably lower than those for some other regions of Ukraine, the investigations started with this population because of the availability of rather reliable measurements and because of the size of this population. The methods developed allowed the estimation of individual thyroid doses. The average values of individual thyroid doses for five age groups (birth years 1983-1986, 1979-1982, 1975-1978, 1971-1974, and < 1971) are 104, 62, 19, 18, and 41 mGy, respectively. The collective thyroid doses were estimated as 83 x 10(3) person-Gy for those born before 1971 and as 38 x 10(3) person-Gy for younger inhabitants. The numbers of expected thyroid cancers in the whole Kiev population are 66 and 130, respectively. 相似文献
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JI Babitskaya IA Budashov SF Chernov IN Kurochkin NV Doroshenko SV Zubov 《Canadian Metallurgical Quarterly》1997,10(6):689-697
A technique for forming Langmuir films from antibodies based on an amphiphilic polyelectrolyte was developed. The physicochemical and immunochemical properties of the Langmuir films obtained were studied. The interaction of HBsAg with the films was found to be described by a model with one binding site, whereas that of HBsAg with antibodies adsorbed on a polystyrene plate, by a model with a positive cooperativity. The use of the novel Langmuir films from antibodies increases the sensitivity of the immunoenzyme assay. 相似文献
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