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1.
Summary By means of closed-loop-stripping and subsequent GC analyses the diel periodicity of release of (Z)-11-hexadecenyl acetate, (E)-8-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, the main constituents of the respective sex pheromone blends ofMamestra brassicae, Cryptophlebia leucotreta andSpodoptera sunia females, was determined.Pheromones, 64. For the 63rd contribution we have taken from: Szöcs, G., Toth, M., Bestmann, H. J., Vostrowsky, O., Heath, R. R., and Tumlinson, J. H., Z. Naturforsch.42c (1987) 165; Pheromones, 62: Bestmann et al.13.  相似文献   

2.
Summary - and -ecdysone were synthesized from labelled cholesterol by premolt crayfish in vivo and by their Y-organs in vitro.  相似文献   

3.
The first known long-range female-released sex pheromone for the family Cerambycidae is reported fromMigdolus fryanus, a sugarcane pest in South America. Although two female-specific compounds, namely, N-(2S)-methylbutanoyl 2-methylbutylamine and N-formyll-isoleucine methyl esters were identified, field tests with synthetic chemicals revealed that only the amide was active and that the amino acid derivative neither increased or decreased trap catches by the amide. This is the first identification of amide as a sex pheromone.  相似文献   

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Summary Fermentation of -sitosterol by a soil pseudomonad resulted in the formation of 4-stigmasten-3-one, 4-stigmasten-3-one-6-ol and 5-stigmasten-3, 7-diol. In case of stigmasterol the metabolites isolated and characterized were 4,22-stigmastadien-3-one, 4, 22-stigmastadien-3-one-6-ol and 5,22-stigmastadien-3, 7-diol.The soil pseudomonad strain (BS-305) is maintained at 4°C on nutrient-agar slants.  相似文献   

6.
Four groups made forecasts of the outcome of the Swedish Parliamentary election in the fall of 2006. They consisted of members of the public, political scientists, journalists writing about domestic politics in Swedish daily newspapers, and journalists who were editing sections of readers' letters in daily newspapers. They estimated, using a 12‐step category scale, which percentage of the votes that they believed seven parties would get in the election. Data were then obtained on the outcome of the election, and on the two opinions polls closest in time to it. When median forecasts were compared across groups, it was found that the group from the public was most successful in forecasting the outcome of the election. This was in spite of the fact that the median error made by individual members of that group was about 50% larger than the median error made by members of other groups. The two polls were less efficient than the group from the public and overestimated the span between the incumbent government and the opposition by a factor of 2. The members of the public and journalists showed some wishful thinking in their forecasts. There were large and consistent individual differences in forecasting ability. Men performed better than women, as did those who expressed more interest and knowledge in politics. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

7.
Summary Acute treatment with 1-tetrahydrocannabinol (1-THC) elevated the concentration of -endorphin-like immunoreactivity (-ELIR) in plasma and in the hypothalamus, but not in the hippocampus of rats habituated to the injection procedure. These effects were not obtained with the psychotropically inert analog of (1-THC), cannabidiol. In animals that had not been habituated to the injection procedure, placebo treatment induced a decrease in hippocampal -ELIR.The authors acknowledge the skillful technical assistance of Mrs Willeke Logtenberg.  相似文献   

8.
Résumé Le présent article traite de la possibilité d'obtenir une méthode de séparation du-caséine par centrifugation à grande vitesse et à basse température et son identification par l'électrophorèse avec la gelée.

Deceased.  相似文献   

9.
Viral infections, including HIV, trigger the production of type I interferons (IFNs), which in turn, activate a signalling cascade that ultimately culminates with the expression of anti-viral proteins. Mounting evidence suggests that type I IFNs, in particular IFN-α, play a pivotal role in limiting acute HIV infection. Highly active anti-retroviral treatment reduces viral load and increases life expectancy in HIV positive patients; however, it fails to fully eliminate latent HIV reservoirs. To revisit HIV as a curable disease, this article reviews a body of literature that highlights type I IFNs as mediators in the control of HIV infection, with particular focus on the anti-HIV restriction factors induced and/or activated by IFN-α. In addition, we discuss the relevance of type I IFN treatment in the context of HIV latency reversal, novel therapeutic intervention strategies and the potential for full HIV clearance.  相似文献   

10.
Summary The effects of some biological parameters on -N-acetylglucosaminidase activity have been investigated inS. oryzae. There is no significant influence of sex and developmental time on the enzyme activity level, which appears in contrast to be greatly influenced by food (wheat or sorghum). Sorghum contains competitive inhibitors which are almost completely removed after dialysis. Fasting relieves this inhibition very quickly, suggesting that inhibitors act directly at the gut level.  相似文献   

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Summary Oral administration to man of 20 mg 11-tetrahydrocannabinol (THC) together with placebo or 40 mg cannabinol (CBN) or 40 mg cannabidiol (CBD) gave evidence of a possible limited interaction of THC with CBN but not with CBD as indicated by average plasma THC levels. Peak CBD and CBN concentrations were similar to that of THC, viz. about 5–8 ng/ml.Supported by the Swedish Medical Research Council and grant MH-00424 from the Veterans Administration.  相似文献   

13.
Summary Cervical specimens were obtained by needle biopsy in connection with caesarean section at term pregnancy. The preparations were superfused in an organ chamber and contractions were registered isometrically. Prostaglandin (PG) E2 and F2 inhibited spontaneous contractions. The stimulatory action of noradrenaline was not influenced by PGF2 but was reduced by PGE2 whereas both PGs abolished the excitatory effect of oxytocin.  相似文献   

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The protective function of the pineal hormone melatonin in the etiology of cancer and carcinogenic activation is increasingly well-established. Low melatonin levels seem to parallel cancer growth. The question arises as to which factors cause the depression of melatonin levels and what the direct effects are. Melatonin is known to be metabolized in the liver by hydroxylation and subsequent conjugation yielding 6-sulfatoxymelatonin as a main product. Nevertheless, the microsomal monoxygenases catalyzing the first step have been poorly investigated. To further characterize these enzymes, typical inducers of three different sub-classes, namely phenobarbital, 7,12-dimethylbenz[a]anthracene, and 17-estradiol, were administered to female Fischer rats. Circadian urinary excretion patterns of melatonin and 6-sulfatoxymelatonin were determined over a 24-hour period on the third (second) day of induction. Liver homogenates were used to monitor the in vitro conversion of melatonin or 6-hydroxymelatonin to 6-sulfatoxymelatonin. Results of both approaches showed the microsomal monoxygenases catalyzing the 6-hydroxylation of melatonin to be strongly inducible by phenobarbital and to a lesser degree by the polyaromatic hydrocarbon 7,12-dimethylbenz[a]anthracene. The dramatic depletion of circulating melatonin as a result of these induction patterns and its possible implications for oncogenesis are discussed.  相似文献   

16.
Archive for History of Exact Sciences - The claim that Galileo Galilei (1564–1642) transformed the spyglass into an astronomical instrument has never been disputed and is considered a...  相似文献   

17.
Résumé Il a été montré que l'appareil réticulaire classique de Golgi dans les cellules pancréatiques des amphibies et des mammifères est un produit artificiel. Un certain nombre de raisons sont proposées pour expliquer ce fait.  相似文献   

18.
F V DeFeudis 《Experientia》1978,34(10):1314-1315
Bicuculline- and strychnine-sensitive components of the binding of GABA, glycine and beta-alanine, which can be demonstrated in the presence of a physiological concentration of Na+, might be related to synaptic receptors.  相似文献   

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Rohrlich claims that “the problem of the arrow of time in classical dynamics has been solved”. The solution he proposes is based on the equations governing the motion of extended particles. Rohrlich claims that these equations, which must take self-interaction into account, are not invariant under time reversal. I dispute this claim, on several grounds.  相似文献   

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