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71.
J Duchesne R Gilles F Mosora 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1975,281(13):945-947
Using the electron spin resonance method, the effect of antioxydants on the number of natural organic free radicals is studied in the case of the diaphragm of the Rat. The effect observed shows an important decrease in the free radical concentration, which may, in the case of ascorbic acid and BHT, lead to their complete disappearance. These results are discussed in the light of the hypothesis according to which antioxydants play a role in the lengthening of the life span because of their fundamental character of inhibitors of free radicals. 相似文献
72.
H. Dahn J. S. Lawendel E. F. Hoegger R. Fischer E. Schenker 《Cellular and molecular life sciences : CMLS》1954,10(6):245-246
Summary Equimolecular amounts of an aromatic or hetero-cyclic aldehyde, glyoxal and cyanideion combine in slightly alkaline aqueous solution to give 4-aryl-2-hydroxytetronimides (I). These are cyclic reductones comparable to imino-ascorbic acid. Oxidation yields dehydro compounds (III) (4-aryl-2, 3-dioxo-4-hydroxy-butyric acid lactones); hydrolysis gives 4-aryl-2-hydroxy-tetronic acids (V) which are easily decarboxylated to -aryl-lactic acids (VII). On hydrogenation, the compounds I are converted to -aryl-, -dihydroxy-butyramides. 相似文献
73.
K. L. Hintze Ann Baker Grow L. J. Fischer 《Cellular and molecular life sciences : CMLS》1977,33(11):1495-1497
Summary Hypophysectomized rats given cyproheptadine (40 mg/kg) for 10 days exhibited a loss of pancreatic immunoreactive insulin and ultrastructural changes in the cytoplasm of beta-cells. Sham-operated animals given cyproheptadine showed identical changes in pancreatic beta-cells except that cytoplasmic involvement progressed to the formation of large vacuoles. The pituitary is not directly involved with the cyproheptadine-induced depletion of pancreatic insulin but plays a role in the formation of large cytoplasmic vacuoles.Acknowledgments. This work was supported by U. S. Public Health Service, grant GM 12675. 相似文献
74.
75.
H Augier G Gilles G Ramonda 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(6):445-447
The study of mercury composition of red Algae Ceranium ciliatum var. robustum, comparatively with other marine organisms and considering its growth and the extent of pollution at various harvesting points: reveals that this seaweed constitutes a conspicuous biological indicator for the littoral mercury pollution. 相似文献
76.
Zusammenfassung Die Hyperglykämie nach einmaliger stossartiger Glukoseinjektion bewirkt einen Durchblutungsanstieg der Bauchspeicheldrüse. Dieser wurde kontinuierlich mit einem elektromagnetischen Blutstrommesser bei narkotisierten Hunden registriet. Der Anstieg setzt sich aus 2 Abschnitten zusammen, wovon der erste unspezifisch auch in der A. femoralis auftritt. 相似文献
77.
Summary (1) After a 24-h passage in a rabbit, fragments of spontaneous isologous mammary carcinoma were implanted under the skin of young R III females. This procedure was found to prevent the appearance of spontaneous mammary tumours in a high percentage of these animals. The subsequent appearance of carcinoma was to be observed in only 23% of treated animals as compared with 51% in controls.(2) After a 24-h passage in a rabbit, fragments of leukotic isologous tissue, implanted subcutaneously in young AkR females, reduced subsequent spontaneous leukomogenesis from 85 to 38%. 相似文献
78.
Th. Wagner-Jauregg Johanna Fischer 《Cellular and molecular life sciences : CMLS》1968,24(10):1029-1031
Summary A new method for the classification of antiphlogistics is described using the growth inhibition ofLactobacillus casei. In this test the fenamic acids and particularly the new class of the Cinnopentazon-antiphologistics (Scha 306, Scha 764 etc.) exhibit bacteriostatic properties of a medium intensity.
Alexander von Muralt zum 65. Geburtstag gewidmet. 相似文献
Alexander von Muralt zum 65. Geburtstag gewidmet. 相似文献
79.
80.
Jung A Maier R Vartanian JP Bocharov G Jung V Fischer U Meese E Wain-Hobson S Meyerhans A 《Nature》2002,418(6894):144
The genome of the human immunodeficiency virus is highly prone to recombination, although it is not obvious whether recombinants arise infrequently or whether they are constantly being spawned but escape identification because of the massive and rapid turnover of virus particles. Here we use fluorescence in situ hybridization to estimate the number of proviruses harboured by individual splenocytes from two HIV patients, and determine the extent of recombination by sequencing amplified DNA from these cells. We find an average of three or four proviruses per cell and evidence for huge numbers of recombinants and extensive genetic variation. Although this creates problems for phylogenetic analyses, which ignore recombination effects, the intracellular variation may help to broaden immune recognition. 相似文献