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161.
BD Palmer JB Smaill M Boyd DH Boschelli AM Doherty JM Hamby SS Khatana JB Kramer AJ Kraker RL Panek GH Lu TK Dahring RT Winters HD Showalter WA Denny 《Canadian Metallurgical Quarterly》1998,41(27):5457-5465
1-Phenylbenzimidazoles are shown to be a new class of ATP-site inhibitors of the platelet-derived growth factor receptor (PDGFR). Structure-activity relationships (SARs) are narrow, with closely related heterocycles being inactive. A systematic study of substituted 1-phenylbenzimidazoles showed clear SARs. Substituents at the 4'- and 3'-positions of the phenyl ring are tolerated but do not significantly improve activity, while substituents at the 2'-position abolish it. Substituents in the 2-, 4-, and 7-positions of the benzimidazole ring (with the exception of 4-OH) also abolish activity. Most substituents at the 5- and 6-positions maintain or increase activity, with the 5-OH, 5-OMe, 5-COMe, and 5-CO2Me analogues being >10-fold more potent than the parent 1-phenylbenzimidazole. The 5-OMe analogue was both the most potent inhibitor, and showed the highest selectivity (50-fold) between PDGFR and FGFR isolated enzymes, and also a moderately effective inhibitor (IC50 = 1.9 microM) of PDGF-stimulated PDGFR autophosphorylation in rat aorta smooth muscle cells. 相似文献
162.
163.
M. Kent K. Christiansen I.A. van Haneghem E. Holtz M.J. Morley P. Nesvadba K.P. Poulsen 《Journal of food engineering》1984,3(2):117-150
Collaborative measurements of the thermal properties of foods and model foods are reported. They were part of a European Cooperation in Science and Technology (COST) project and provide data on thermal diffusivity and thermal conductivity of fish paste, meat paste, yoghurt, milk powder, apple pulp. ‘Model’ foods also examined were various mixtures of carrageenan, sugar and water and a monodisperse ‘powder’ of glass beads. Dependence of the measured properties on temperature, density and composition was also examined. 相似文献
164.
Binding properties of bovine colostral anti-dinitrophenyl (dnp) immunoglobulins g2 (igg2) 总被引:1,自引:0,他引:1
The number of combining sites per mole of bovine colostral anti-DNP IgG2 was found to be 2 and the total affinity constant was 0.81 X 10(4) M-1. Unlike bovine colostral IgG1, the nonspecific binding of H3-epsilon-DNP-1-lysine by IgG2 as a function of increased concentrations, did not show a negative, cooperative slope. Spectral measurements made with anti-DNP IgG2 in the reference cell vs. anti-DNP IgG2 plus hapten in the experimental cell revealed a hypochromic, red shift from 363 to 365 nm. If the reference cell contained hapten, a red shift from 280 to 283 nm and an enhancement in the extinction coefficient of IgG2 was observed. These spectral changes were not observed if nonspecific IgG2 was substituted for anti-DNP IgG2 in the experimental cell. The enhancement in the extinction coefficient was interpreted to be due to a possible exposure of previously buried tryosine and tryptophan residues. 相似文献
165.
166.
167.
The application of different methods of tissue culture, in particular, investigations on trophoblast cells outside the mother's body, opens new possibilities for understanding pathogenesis of premature interruption of pregnancy caused by the hormonal and metabolic disorders. To study the effects of various hormones (Choriogonien, estrone and estradiol) on the growth and development of trophoblast cells the method of tissue culture was applied. 683 histological preparations, obtained after incubating trophoblast tissues with and without hormones were examined. It was established that choriogonine in doses of 5-100 IU/L stimulated growth in trophoblast cells but 200-400 IU/L of hormone did not increase this stimulating effect. Estrone and estradiol added to incubated tissues in doses of 60-120 IU/L brought about no changes or else had a weak effect on development of cultivated tissues. When choriogonine (or estrone) was added to the trophoblast tissues together with blood serum taken from women in danger of premature interruption of pregnancy the negative effect of the serum on the development of the trophoblast cells was prevented. 相似文献
168.
Looking for a coronary artery restenosis model closer to human pathology, a protocol of balloon injury/reinjury (plaque of dilatation) in swine coronary artery was designed. Pig coronary arteries (n = 24) were dilated for this study: 12, group 1, once (sacrifice at 10.0 +/- 2.2 weeks); 6, group 2, twice at 2-wk intervals (sacrifice at 5.2 +/- 0.2 wk); 6, group 3, twice at 4-wk intervals (sacrifice at 9.3 +/- 1.9 wk). A single overdilatation resulted in an eccentric neointimal hyperplasia representing half of the wall area (group 1, 45.6 +/- 5.1%). In animals (groups 2 and 3) subjected to redilatation, fracture length, ratio of fracture length to internal elastic lamina (IEL) circumference, and neointimal hyperplasia response were similar to those observed in group 1. In group 3, the shape of the lesion appeared more concentric and the fracture of the IEL more fragmented than in group 1. Although this model of injury/reinjury did not lead to more severe intimal hyperplasia, performing a second angioplasty at the same site did lead to a more concentric intimal response, related to multiple fractures of the IEL. 相似文献
169.
This paper presents the results of a study on the introduced, free-ranging patas monkey population of Southwestern Puerto Rico (SWPR). It describes information on the population size, social group composition, diet, daily ranging patterns, and patas home range during a 3 year period. The patas monkey population in the study area consisted of approximately 120 individuals in four heterosexual groups and several all-male bands. Within their home ranges (26.8 km2), the population density was 4.47 individuals/km2. Home range size among the population's four heterosexual groups varied from 3.72 km2 to 15.39 km2, and minimum daily distance traveled ranged from 0.8-2.0 km. In general, the social structure and mating system of this population parallels what has been described for African populations. However, habitat use, ranging behavior, and the quality of intergroup interactions suggests that patas of this population exhibit territorial behavior. 相似文献
170.
TC Krejcie JA Jacquez MJ Avram CU Niemann CA Shanks TK Henthorn 《Canadian Metallurgical Quarterly》1996,24(6):569-588
The gamma and Erlang density functions describe a large class of lagged, right-skewed distributions. The Erlang distribution has been shown to be the analytic solution for a chain of compartments with identical rate constants. This relationship makes it useful for the analysis of first-pass pulmonary drug uptake data following intravenous bolus administration and the incorporation of this analysis into an overall systemic drug disposition model. However, others have shown that one Erlang density function characterizes the residence time distribution of solutes in single tissues with significant systematic error. We propose a model of two Erlang density functions in parallel that does characterize well the arterial appearance of indocyanine green, antipyrine, and alfentanil administered simultaneously by right atrial bolus injection. We derive the equations that permit calculation of the higher order moments of a system consisting of two parallel Erlang density functions and use the results of these calculations from the data for all three indicators to estimate pulmonary capillary blood volume and mean transit time in the dog. 相似文献