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111.
Tamara Kubasova Sára Antal Z. Somosy G. J. Köteles 《Radiation and environmental biophysics》1984,23(4):269-277
Summary For studies on cell membranes, mice were exposed to mixed neutron + gamma reactor-radiation in the range of total doses from 0.5 to 4.5 Gy. Changes in functional activity of plasma membranes of erythrocytes, platelets, and lymphocytes were followed by a lectin-binding technique at various intervals afterwards. The amount of3H-concanavalin A bound to cells altered considerably during the 1st h after irradiation in all cell types. Lymphocytes and platelets, however, were more sensitive than erythrocytes as increased lectin-binding could already be observed after 0.5 Gy. The binding ability of these cells performed oscillatory behaviour. In addition, alterations in shapes and ultrastructure of cell surfaces and intracellular membranes were observed. 相似文献
112.
Résumé Une candidose intestinale associée à une tumeur épithéliale, à métaplasie glandulaire, à pouvoir invasif marqué, provoquant une gêne du transit, a été découverte chez un Babouin de Guinée,Papio papio (Desm.) de la collection du Parc zoologique de Paris. A cette occasion nous avons rapporté les résultats concernant deux autres affections du tube digestid de nos Babouins captifs.
Report of a case of candidiasis of the digestive tract associated to an obstructive epithelial tumor, with great invasive ability, in a captive Baboon,Papio papio (Desm.). Included is a discussion of the incidence of some intestinal disturbances involving candidiasis of subhuman Primates.相似文献
113.
114.
Árpád Németh 《Histochemistry and cell biology》1978,59(2):149-151
Summary Birefringence and fluorochrome lipid staining with benzpyrene are demonstrated as simple morphological methods to reveal the presence or absence of surfactant lipids in human newborn lung tissue. Lack of lipid birefringence proves to be an associated finding in the lungs of premature infants with hyaline membrane disease, indicating the possible pathogenetical importance of surfactant deficiency. 相似文献
115.
Hans R. Gislerød 《Plant and Soil》1982,69(3):445-456
Summary The air content in three types of propagation media, Jiffy-7 and Jiffy-9 which are Sphagnum peat and Grodan which is rockwool,
were investigated when they were held at moisture tensions of 0,6 and 12 cm measured from the base of the media. At 0 cm tension
the air content (vol. %) was highest in Jiffy-9 and lowest in Jiffy-7. At 12 cm tension the air content was higher in Grodan
than in Jiffy-9 and Jiffy-7.
Oxygen diffusion coefficients (ODC) and oxygen diffusion rates (ODR) were measured at the different air contents. At air contents
below 20 vol. % ODC was about the same for Jiffy-9 and Grodan but at air contents above 20 vol.% it was larger for Jiffy-9
than for Grodan. The oxygen diffusion rate was measured at 0, 4 and 8 cm moisture tension. At all tensions it was approximately
20% higher in Jiffy-9 than in Grodan and Jiffy-7. The ODR in Jiffy-7 and Grodan were affected equally at the same tension,
although Grodan contained more air.
Report no 253 相似文献
116.
The changes in intracellular oxygen tension and energy metabolism of the cat brain cortex were studied by surface fluororeflectometry during haemorrhagic shock. The results may be summarized as follows. (a) Intracellular oxygen tension, i.e. the maximum cortical NAD reduction obtained during nitrogen gas inhalation decreased gradually during the hypovolaemic phase of shock and finally, the brain cortex became ischaemic. (b) Partial uncoupling of the cerebrocortical mitochondrial respiration and oxidative phosphorylation appeared in the very early period of bleeding, as indicated by the overshot of the cortical NAD/NADH redox state towards oxidation subsequent to the cessation of nitrogen gas inhalation. Partial uncoupling of mitochondrial respiration and oxidative phosphorylation became more pronounced during the later phases of bleeding, finally, the mitochondrial electron transport stopped. In line with these changes the frequency and the amplitude of ECoG decreased gradually and markedly during the hypovolaemic phase of shock. (c) Microcirculation and energy metabolism of the cat brain cortex were severely and irreversibly damaged during the hypovolaemic phase of shock. This was clearly shown by the fact that in the majority of experiments the nitrogen anoxia after reinfusion failed to bring about changes in the cortical NAD/NADH redox state and the ECoG changes occurred during bleeding did not improve after reinfusion. It is concluded that the early disturbances of cerebrocortical energy metabolism play an important role in the development of neural and vascular lesions of the brain that occur during haemorrhagic shock. 相似文献
117.
Elastosis, the significant increase of elastic tissue, was identified by histochemical methods in 45 (53.5%) cases of an unselected series of breast cancers. They were all invasive ductal carcinomas with or without tubular differentiation. The highest proportion of tumors with elastosis was found in the "scirrhous" type of carcinomas. Elastosis was preponderantly of the focal variety, periductal and perivenous. The affected ducts were of large calibre, containing a normal, benign hyperplastic or carcinomatous epithelium. There were not observed correlations with the grade of malignancy and the extent of axillary lymph node metastases. 相似文献
118.
A.J.v.d. Broek A.I.A. Broess M.J.v.d. Heuvel H.P. de Jongh J. Leemhuis K.H. Schonemann J. Smits J. de Visser N.P. van Vliet F.J. Zeelen 《Steroids》1977,30(4):481-510
Using the strategy based on the Hansch method which analyses effects of substituents on biological activity in terms of their hydrophobic, electronic and steric effects we selectively synthesised a series of 11β-substituted-17α-ethynyl-4-estren-17β-ols that combine ease of synthesis with good discrimination between these factors aiming at finding the compounds with optimum biological activity in that series. The compounds were tested quantitatively in the Clauberg test (rabbit) and the ovulation inhibition test (rat). The differences in biological activity could reasonably be correlated with two steric effects introduced by the 11β-substituent. These were a change in the overall shape of the 11β-substituent and the angular methyl group, and direct steric hindrance of the steroid-receptor protein binding. Some exceptions were found possibly due to metabolic conversion of these compounds to the corresponding 11β-substituted-17α-ethynyl-l,5,5(10)-estratriene-5, 17β-diols. 相似文献
119.
Mohamed Saïd Hifnawy Jacqueline Vaquette Thierry Sévenet Jean-Louis Pousset André Cavé 《Phytochemistry》1977,16(7):1035-1039
Stems and leaves of Myrtopsis macrocarpa, M. myrtoidea, M. novae-caledoniae and M. sellingii yielded terpenes, sterols, coumarins, alkaloids (furoquinolines and quinolones) and amides. A new quinolone (8-methoxy flindersine) occurs in Myrtopsis macrocarpa, a new amide (N-benzoyltryptamine) in M. myrtoidea, two new coumarins (myrsellin and myrsellinol) and a new dihydrofuroquinoline (myrtopsine) in M. sellingii. Structures of the new compounds are proposed from chemical and spectroscopic evidence. 相似文献
120.
Cell suspension cultures of parsley and soybean were incubated for 38 h with 14C-labeled benzo[a]pyrene; autoclaved cultures were used as controls. Metabolites were isolated by a sequential extraction procedure and further studied by chromatography or by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The soluble metabolites amounted to 1–2.2% in the case of parsley cells, and 19–28% in the case of soybean cells. These metabolites varied in polarity, some being soluble in organic solvent or aqueous buffer while other metabolite fractions were soluble only in hot aqueous sodium dodecylsulphate. In addition, a significant amount of an insoluble metabolite fraction was isolated from the culture fluid as well as the cellular material of soybean suspension cultures.Abbreviations BP
benzo[a]pyrene
- SDS
sodium dodecyl sulfate
- TCA
trichloroacetic acid 相似文献