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In a chromosome study on leucocyte cultures made in 13 patients treated with chlorpromazine, 15 treated with perphenazine, and nine treated with lysergide, a significantly higher frequency of gaps, breaks, and hypodiploid cells in the patients treated with perphenazine and lysergide occurred compared with the 41 controls studied. It is concluded that if some drugs can induce major chromosome abnormalities, and less toxic alternatives are available, the latter should be used in preference. 相似文献
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Erik Peper 《Biological cybernetics》1970,7(3):107-112
Summary Experiments with feedback stimulation triggered from the subject's electroencephalogram result in changing the sequential time series of intervals of occipital alpha and intervals of little or no alpha EEG activity. The rate of recurrence of alpha and no-alpha EEG can be changed by regulating the external feedback stimuli or by asking the subject to change his internal state. Four different paradigms were investigated and the results interpreted in terms of the hypothesis that oculomotor functions regulate the occurrence and nonoccurrence of alpha.This work was supported by NIGMS Grants 5 PO1 GM 14940-04 and GM 15006-03.Most of this research was conducted at the Perception Laboratory, Veterans' Administration Hospital, Bedford, Massachusetts, with the cooperation of Dr. Thomas B. Mulholland. 相似文献
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Erik Schwarzbach 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1968,38(7):301-303
Zusammenfassung Die Schätzung der Varianzkomponenten bei Versuchen mit festen Variabilitätsursachen, z. B. bei der Prüfung von Sorten, Behandlungen usw., ist nur dann sinnvoll, wenn die Varianzkomponenten so definiert sind, daß ihre Summe der Gesamtvarianz gleich ist, d. h. daß sie sich additiv verhalten. Will man die so definierten Varianzkomponenten erwartungstreu schätzen, muß man die Überhöhung der mittleren Quadrate, die durch Division mit Freiheitsgraden statt mit der Gruppenzahl entstanden ist, wieder korrigieren. Diese Korrektion entfällt bei der Schätzung der Varianz von Zufallswirkungen.Die Erwartungswerte der mittleren Quadrate der üblichen varianzanalytischen Zerlegung und die erwartungstreuen Schätzungen der additiv definierten Varianzkomponenten werden am Beispiel eines Versuches mit zwei konstanten Variabilitätsursachen und einer Zufallseinwirkung dargelegt.
Estimating variance components in a fixed model of variance analysis
Summary The partition of a variance into components in experiments with fixed effects, i.e. experiments with varieties, treatment etc., is meaningful only if components are defined as additive parts of a whole. This also demands that the sum of the components of variance be equal to the total variance. Such additivity of the components of variance is achieved by appropriate definitions of the components of variance. Unbiassed estimates of the additively defined components of variance are obtained by a simple correction which eliminates the influence of degrees of freedom on the calculation of mean squares. This correction is not needed for the estimation of variances of random effects.The expected values of mean squares for the partition of variance and formulas for unbiassed estimates of additively defined components of variance are demonstrated in an experiment with two fixed effects and one random effect.相似文献
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Rolf Elofsson Tiit Kauri Sven-Olle Nielsen Jarl-Ove Strömberg 《Cell and tissue research》1966,74(4):464-473
Summary The cellular localization of biogenic monoamines in crustaceans was studied by means of a highly specific and sensitive fluorescence method devised by Falck and Hillarp. It was found that neurons displaying specific fluorescence in the central nervous system were confined to the protocerebrum, the medulla externa and interna and the ventral nerve cord. The method allows a distinction between the fluorophores of 5-hydroxytryptamine (and 5-hydroxytryptophan), which emit the yellow light, and the fluorophores deriving from the catecholamines (and DOPA), which emit the green light. Green-fluorescent neurons occurred abundantly in the aforementioned parts of the central nervous system while yellow-fluorescent neurons were sparsely present in the same parts.The present work has been carried out at the departments of Histology and Zoology at the University of Lund. The authors take great pleasure in expressing their warmest thanks for laboratory facilities, provided by Professors Erik Dahl (Zoological Institute) and Bengt Falck (Histological Institute).The research reported in this document has been sponsored by the Air Force Office of Scientific Research under Grant AF EOAR 66-14 through the European Office of Aerospace Research (OAR), United States Air Force and by a grant from the Swedish Natural Science Research Council 99-32 (nr 5995). 相似文献