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11.
M. Pavlović D. Petković M. Cvetković D. J. Macut K. Zdjelar M. Nešić O. Bosnić R. Radulović M. Mihajlović 《Cellular and molecular life sciences : CMLS》1995,51(9-10):941-944
The mechanism of the positive inotropic effect of prostacyclin (PGI2) (2.6×10?6 mol/l) on the isolated right ventricle of rat heart was studied. Our results show that the positive inotropic effect of prostacyclin is produced indirectly through beta adrenoceptors and slow Ca2+ channels, because blockade of slow Ca2+ channels with verapamil (10?6 mol/l) and beta adrenoceptors with propranolol (10?6 mol/l) abolishes this effect. Alpha adrenoceptors do not mediate the action of PGI2. 相似文献
12.
J. Komender H. Košcianek-Malczewska K. Ostrowski 《Cellular and molecular life sciences : CMLS》1965,21(5):249-251
Résumé Les auteurs ont déterminé le contenu en acides nucléiques dans le foie du rat après la congélation-dessication dans du méthanol.
Après cette technique, une grande partie de DNA était soluble dans l'eau.
相似文献
13.
Zusammenfassung Bei Prüfung des Einflusses vonp-Benzochinon auf die Aktivität der partiell gereinigten IES-Oxidase aus Wurzeln von Maiskeimlingen wurde bei Konzentrationen von 5×10–6 bis 5×10–4
M eine 50-bzw. 100%ige Hemmung beobachtet. 相似文献
14.
Zusammenfassung Es wird gezeigt, dass Schlafentzug die Ausscheidung der 5-Hydroxyindolessigsäure und der Xanthurensäure vermehrt und diejenige der Antranilsäure herabsetzt. 相似文献
15.
Milada Stuchlová Horynová Milan Raška Henrik Clausen Jan Novak 《Cellular and molecular life sciences : CMLS》2013,70(5):829-839
Glycosylation abnormalities have been observed in autoimmune diseases and cancer. Here, we compare mechanisms of aberrant O-glycosylation, i.e., formation of Tn and sialyl-Tn structures, on MUC1 in breast cancer, and on IgA1 in an autoimmune disease, IgA nephropathy. The pathways of aberrant O-glycosylation, although different for MUC1 and IgA1, include dysregulation in glycosyltransferase expression, stability, and/or intracellular localization. Moreover, these aberrant glycoproteins are recognized by antibodies, although with different consequences. In breast cancer, elevated levels of antibodies recognizing aberrant MUC1 are associated with better outcome, whereas in IgA nephropathy, the antibodies recognizing aberrant IgA1 are part of the pathogenetic process. 相似文献
16.
Autumn musters of bison ( Bison bison ) on Antelope Island State Park, Utah, conducted annually since 1987, provided data on temporal and age-specific reproductive patterns and a basis to evaluate the efficacy of management measures implemented to elevate reproductive performance in the herd. Pregnancy rates were variable and low ( x = 46.2%) in comparison to other free-ranging, noncommercial bison herds in North America. Cows in the 3- and > 6-yr range age classes exhibited lower-than-expected pregnancy rates ( P r = 0.64, P = 0.047) linear decline of 2.5% per annum. Variance in distribution of fetal ages observed in 6 yr indicates substantial temporal fluctuation. Long-term reproductive performance of cohorts born prior to implementation of management measures did not differ from that of cohorts born subsequent to these changes. 相似文献
17.
Cross-sectional approach for clustering time varying data 总被引:2,自引:0,他引:2
Cluster analysis is to be performed on a three-mode data matrix of type: units, variables, time. A general model for calculating the distance between two units varying in time is proposed. One particular model is developed and used in an example concerned with clustering of 23 European countries according to the similarity of energy consumption in the years 1976–1982.Supported in part by the Research Council of Slovenia, Yugoslavia. 相似文献
18.
D. Lamošová M. Zeman M. Macková E. Gwinner 《Cellular and molecular life sciences : CMLS》1995,51(9-10):970-975
The chick pineal gland exhibits circadian rhythms in melatonin synthesis under in vivo and in vitro conditions. A daily rhythm of melatonin production was first detectable in pineal glands isolated from chick embryos at embryonic day 16 and incubated under a LD cycle. All pineal glands isolated from 17-day-old and older embryos were rhythmic while no gland isolated at embryonic day 14 and 15 exhibited a daily rhythm in melatonin synthesis. Melatonin production in static cultures of embryonic pineal cells was rhythmic over 48 h if the cells were kept under a LD cycle. When embryonic pineal cells were incubated in constant darkness the rhythm in melatonin production was damped within 48 h. These results suggest that chick pineal cells from embryonic day 16 onwards are photosensitive but that the endogenous component of the melatonin rhythm is not completely developed at that age. A soluble analogue of cAMP stimulated and norepinephrine inhibited melatonin synthesis in cultured embryonic pineal cells. These findings indicate that the stimulatory and inhibitory pathways controlling melatonin synthesis in the mature pineal gland are effective in pineal cells isolated from chick embryos at least 2 days before hatching. 相似文献
19.
V. Pliška M. Meyer-Grass N. Bersinger L. Carlsson P. Melin H. Vilhardt 《Cellular and molecular life sciences : CMLS》1980,36(10):1145-1146
Summary Lysine vasopressin tritiated at meta position of tyrosine (1.9 Ci/mmole) decomposes during a long storage period, mainly as a result of radiolysis. The loss of specific activity by isotopic exchange with water is slow. The nonlabelled peptide undergoes only very minute decomposition (polymerization). Specific radioactivity declines with a half life of 47.4 months.Acknowledgments. This research was supported by Swiss National Science Foundation, grant No.3.040.76 (V.P.). Some of the measurements (years 1969–70) were carried out at Roche Institute of Molecular Biology, Nutley, N.J., USA. 相似文献
20.
M. Marušić 《Cellular and molecular life sciences : CMLS》1978,34(6):806-807
Summary Whether or not parental B lymphocytes cooperate with F1 T lymphocytes depends upon the environment in which parental bone marrow cells differentiate. Only those parental B lymphocytes that have differentiated in the F1 environment are able to cooperate with F1 T lymphocytes.Postdoctoral Investigator supported by Subcontract No. 3322 from the Biology Division of Oak Ridge National Laboratory to the University of Tennessee and by the Fulbright-Hays Program.Operated by the Union Carbide Corporation for the Department of Energy. 相似文献