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11.
In Hank's balanced salt solution EL-4 ascites thymoma cells possessed endogenous respiration which was sufficient for the maintenance of their ATP level: pH decrease down to 6.0 had no effect either on endogenous respiration or the ATP level. Glucose had no influence on the respiration of EL-4 cells but inhibited that of Ehrlich ascites carcinoma (EAC) cells by 40% (Crabtree effect); respiration of the both cell lines was strongly (4-fold) inhibited after simultaneous addition of glucose, lactate and pH decrease. EL-4 cells had no endogenous glycolysis; EAC cells showed a low level of glycolysis only after pH decrease. Glucose addition led to activation of glycolysis (both inhibited 2-fold after a decrease of pH down to 6.0. The respiration inhibition at pH 7.3 and 6.0 caused no decrease of ATP depletion when glucose was present in the medium; this result may be due to suppression of ATP consumption. Incubation of EL-4 cells under respiration and glycolysis deficiency conditions resulted in a sharp ATP depletion; pH decrease delayed this depletion. 相似文献
12.
H G van der Poel M E Boon L P Kok E A van der Meulen R D van Caubergh W C de Bruijn F M Debruyne 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1991,13(5):307-315
An image analysis method of grading histologic sections of bladder carcinoma was tested. The method was new in four respects. First, for fixation of the biopsies a coagulant fixative was used. Second, 2-microns plastic sections were used to ensure the reproducibility of nuclear imaging. Third, a new stereologic approach was used for calculation of the nuclear volume and DNA content. Fourth, for the classification rule the morphometric, densitometric and texture features were used in concert. The IBAS 2000 instrument was used for the measurements. Texture analysis of the chromatin patterns was performed using Markovian texture features. Using discriminant analysis, of 22 parameters, 2 morphometric, 2 densitometric and 3 texture features were selected for the classification rule. With them, 89% of the bladder carcinomas were correctly classified into the three grades. All grade III tumors were classified correctly. Among the features tested, the densitometry of the DNA had the highest F values. All of the grade III tumors and 45% of the grade II tumor group had DNA histograms indicating aneuploidy. This study showed that plastic-embedded material is well suited to morphometry and densitometry and can be used for quantitative grading of bladder carcinoma. 相似文献
13.
In the present study we report on the histotopographical distribution of carbohydrate-binding proteins in the prostate and seminal vesicle of sexually mature NMRI mice using a panel of fluorescein-isothiocyanate labelled neoglycoproteins and asialoglycoproteins. Additionally, biochemical analysis using affinity chromatography and SDS-gel electrophoresis was performed to purify and characterize the respective proteins from the tissue. Our histochemical results clearly demonstrate the presence of endogenous receptors for the carbohydrate part of glycoconjugates in both glands. In the prostate a distinct staining was seen after incubation with melibiose-BSA-FTC, glucuronic acid-BSA-FTC and asialofetuin-FTC (only in the ventral prostate). In the epithelium of the seminal vesicle a weak staining occurred after incubation with asialofetuin-FTC and maltose-FTC. In the stroma of both accessory sex glands a distinct binding of several (neo)glycoproteins specific for beta-galactoside-binding proteins was observed which could be attributed to a beta-galactoside-binding lectin. Indeed biochemical analysis ascertained presence of such a histochemically detectable activity. We assume that the carbohydrate-binding proteins of the stroma, which were obviously linked to the elastic fibers, could play a role in the organisation of the extracellular matrix in the interstitium of the glands. 相似文献
14.
Abstract. Plant functional types are a necessary device for reducing the complex and often uncharted characteristics of species diversity in function and structure when attempting to project the nature and function of species assemblages into future environments. A workshop was held to review the current methods commonly used for defining plant functional types, either globally or for particular biomes, and to compare them with the field experiences of specialists for specific biomes of the world. The methods fall into either an objective and inductive approach or a subjective and deductive approach. When the different methods were tested, it was generally found that the classification for one site or environment was not wholly applicable to a different site or environment. However, the degree of change which is necessary for adjustment between environments may not prove to be a major limitation in the use of functional types. 相似文献
15.
S M Kappes M D Bishop J W Keele M C T Penedo H C Hines M D Grosz G A Hawkins R T Stone S L F Sunden C W Beattie 《Animal genetics》1994,25(3):133-140
Seven bovine erythrocyte antigen loci and three serum protein loci were tentatively assigned to chromosomes or synteny groups by linkage analysis to previously assigned microsatellite DNA markers. The erythrocyte antigen locus EAB was mapped to synteny group U27; EAC to chromosome 18, synteny group U9; EAL to chromosome 3, synteny group U6; EAS to chromosome 21, synteny group U4; EAZ to chromosome 10, synteny group U5; EAR' to chromosome 16, synteny group U1; and EAT' to chromosome 19, synteny group U21. The vitamin D binding protein (GC) and albumin (ALB) loci were assigned to chromosome 6, synteny group U15 and post-transferrin 2 (PTF 2) to chromosome 19, synteny group U21. 相似文献
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F Velge-Roussel C Verwaerde J M Grzych A Auriault A Capron 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(7):2527-2532
A rat IgE mAb specific for larval Ag (26 kDa, 56 kDa) has been shown to protect rats against Schistosoma mansoni infection. Immunizations of Lou/M rats performed with this IgE (Ab1) induced the production of antiidiotypic antibodies (Ab2). Moreover, after this Ab2 production, anti-antiidiotypic antibodies (Ab3) were revealed. The screening of Ab3 isotypes showed the presence of IgG Ab3 and more interestingly of IgE Ab3, i.e., the same isotype as Ab1. These IgE and IgG antibodies recognized predominantly the 26-kDa Ag and were cytotoxic for schistosomula in the presence of platelets for IgE Ab3 and eosinophils for IgG Ab3. Both IgE and IgG Ab3 conferred by passive transfer protective immunity to infected rats (up to 50%). Thus the immunization with an IgE mAb led in part to the production of Ab3 of the same isotype as Ab1. In conclusion, these results suggest that the isotype selection of the antibodies of the third generation (Ab3) might be influenced by the Ab1. The respective role of the idiotope and isotype of Ab1 in isotype regulation is discussed. 相似文献