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91.
Antonio G. Gonzalez Jaime Bermejo Barrera Francisco J. Tolfdo Marante 《Phytochemistry》1983,22(4):1049-1050
The fruit bodies of the Basidiomycete Scleroderma polyrhizum have been shown to contain the steroids ergosta-4,6,8(14) 22-tetraen-3-one and 5α,8α-epidoxyergosta-6,22-dien-3β-ol and also palmitic and oleic acids. 相似文献
92.
A neutral growth inhibitor, isolated from methanolic extracts of sunflower seedlings, was characterized by spectral data as caprolactam. Light-grown se 相似文献
93.
From the Silberberg Quarry, type locality of the Silberberg Formation (Martini &Ritzkowski 1968), some planktonic foraminifera are described:Globigerina officinalis Subbotina, Globigerina ouachitaensisHowe &Wallace,G. praebulloides leroyi Blow &Banner, G.praebulloides occlusa Blow &Banner which taxa are here suggested to form intergrading morphotypes within the range of variation of a population dominated byG. officinalis. In addition,G. cf.danvillensis Howe &Wallace is found. The planktonic fauna, together with some elements in the benthonic fauna, suggests a possible correlation with the Danville Landing Member of the Jackson Formation, Louisiana, traditionally ascribed to the Upper Eocene. There is some similarity with European Uppermost Eocene — Lower Oligocene faunas described by various authors. The Silberberg Formation was suggested to be a Neostratotype for the Latdorfian Stage of the Lower Oligocene byMartini &Ritzkowski (1968). It is suggested that the Silberberg Formation may well be coeval with the Upper Priabonian as proposed byCita 1969. 相似文献
94.
95.
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
96.
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
97.
98.
Monotropa Hypopitys L. — an Epiparasite on Tree Roots 总被引:1,自引:0,他引:1
99.
100.
Z Yu P S Williams H J Smith R D Sewell A Patel J P Gonzalez 《Journal of enzyme inhibition》1989,3(2):103-117
Some 2-substituted-(2'-aminophenyl)-4-thioxohydantoic acids (o-amino PTC-amino acids) have antinociceptive activity when administered (icv) alone (IC50 = 0.04-0.87 microM/animal) and show a striking prolongation of the antinociceptive action of (D-Ala-2 D-Leu5)-enkephalin (DADL) in combination. The effects are thought to be mediated via opioid receptors since they are naloxone-reversible. Although inhibitors of the enkephalin degrading puromycin-insensitive, bestatin-sensitive aminopeptidase (possibly aminopeptidase M) their action is weak (IC50 = 32 microM leucine, 536 microM, glycine) and they might be considered to have a direct antinociceptive effect on opioid receptors. The titled compounds constitute novel 'lead' compounds for the development of potent aminopeptidase M inhibitors. 相似文献