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971.
Zusammenfassung DNS-Messungen an Interphasekernen vonArtemia salina parthenogenetica 2n undArtemia salina anfigonica zeigen ein Mengenverhältnis von 1.21, während zwischenArtemia salina parthenogenetica 4n undArtemia salina anfigonica DNS Werte im Verhältnis 21 gefunden wurden.  相似文献   
972.
973.
Systematic (i. p.) or intra-amygdaloid injections of kainic acid elicit typical generalised convulsive seizures with typical electrographic correlates. Depending on the survival time and the amount of neurotoxin administered, secondary pathological damage is invariably found in various brain structures removed from the injection site such as various hippocompal fields, midline thalamic nuclei and neocortical layers III and VI. Various lines of evidence are reported which suggest that the secondary pathological damage is not due to the spread of the neurotoxin but to the epileptic status it induces.  相似文献   
974.
975.
Every tenth person in Central Europe is a pollinosis patient. The time of ripening and release of pollen, as well as pollen flight, all depend on the weather. Because each year is different from every other, mean values from pollen calendars do not provide any practical help for allergy-sufferers. For this reason, in many European countries, measuring networks have been established during the last 10 years as a basis for forecasting the prevalence of airborne pollen for the following 2–3 days, in connection with the weather forecast. Cooperation and communication also exist on a European level, and a European Pollen Database has been established.  相似文献   
976.
977.
978.
The comparison of the effects of 4 oximes upon the cerebral cholinesterases reactivation after intoxication with paraoxon shows that the best results are obtained with toxogonine and 1574 [(carbaldoxime-4 pyridinium)-1(methyl-1 imidazolium-3)-3 propane]. The reactivation power of this latter compound seems due to the ease with which it can pass through the blood-brain barrier.  相似文献   
979.
Summary A simple and inexpensive modification of the Kopf model 900 small animal stereotaxic instrument allows it to be used temporarily as a precision polyacrylamide slab gel slicer.Supported by the Alfred P. Sloan Foundation.  相似文献   
980.
E C Mundall  S S Tobe  B Stay 《Nature》1979,282(5734):97-98
Vitellogenins are yolk protein precursors that are synthesised in the liver of lower vertebrates in response to ovarian hormones, and in the fat body tissue of insects, under the influence, in most species, of juvenile hormone (JH) from the corpora allata (CA). Vitellogenins are normally restricted to females, although in male amphibians and roosters their synthesis can be induced artificially by the injection of oestrogens. Thus female specificity is maintained by hormonal differences between adult males and females. In insects, on the other hand, because the CA of adults of both sexes are active, it appeared that male fat body could not normally respond to JH by synthesising vitellogenin. However, precise JH synthetic rates of male CA are only known in Schistocerca gregaria and Diplopterapunctata, in which species they are low compared to the rates in the female glands. The absence of vitellogenin in adult males could thus be due to inadequate JH titres. We report here that synthesis of vitellogenin can indeed be induced in males of Diploptera by implantation of female CA or application of Diploptera by implantation of female CA or application of a JH analogue, ZR512 (Zoecon), and that implanted oocytes take up the vitellogenin.  相似文献   
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