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61.
Ulla Martin Hermann Martin Martin Lindauer 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1978,128(3):193-201
Summary It has been possible — by transplantation of brain tissue (i.e. mushroom-bodies) — to perform an interindividual transfer of a learned time-signal in honeybees. The information of the donor bees becomes determinative for the temporal activity pattern of the recipients about 3 to 4 days following transplantation.As seen from histological investigations done in parallel, the donor tissue is treated as a xenograft by the recipient's organism including disintegration and encapsulation processes. These observations give evidence for a humoral transfer of information.The results are discussed from the point of view of the analysis of the mechanism of time reception.Dedicated to Prof. Dr. H. Autrum on the occasion of his 70th birthdaySupported by the Akademie der Wissenschaften und der Literatur zu Mainz, the Stiftung Volkswagenwerk and the Deutsche ForschungsgemeinschaftAll observations done were individual per hand registrations. We want to give thanks to all people in the department who helped us to do the experiments. 相似文献
62.
63.
Eighteen Adh-negative mutations were selected with 1-pentyn-3-ol after feeding of formaldehyde. Twelve of the 18 were shown by cytological and genetic analysis to be deletions. Cytological examination of the deletions allowed us to localize the Adh gene to a region including bands 35B3-5 on the left arm of chromosome 2. The deletions were also used to order known visible loci located near Adh.--The vital loci near Adh were also investigated. A total of 109 lethal mutations were generated with EMS and 33 of these, localized within a region defined by the overlap of two of the deletions, were found to belong to 13 complementation groups. If one includes three other loci known to belong there (el, Adh and Sco) a total of 16 complemetation groups have been identified in the region close to Adh. 相似文献
64.
Starting from a chloroform-methanol (2: 1 v/v) insoluble pellet of rat brain myelin, two pure proteins W1 and W2 were isolated by sodium dodecylsulphate preparative polyacrylamide gel electrophoresis. Their amino acid composition was compared. Antibodies against these proteins were prepared in rabbits. It was found that the two antigens have common antigenic similarities. The presence of one precipitin line of identity when myelin or isolated W1 and W2 from different animals were tested, led to the conclusion that there was no species specificity. The importance of the availability of such antisera is discussed. 相似文献
65.
Nitrogenase activity of ‘membrane-free’ extracts, produced from nitrogenstarved Rhodospirillum rubrum to which 4 mM NH+4 had been added is only about 10% of the activity in the control. The activity could be restored to 80% by including the membrane component, earlier found to activate R. rubrum nitrogenase, in the reaction mixture. The relation between this ‘switch-off/switch-on’ effect and the function of the membrane component is discussed.Hydrogen production catalyzed by R. rubrum nitrogenase is also dependent on activation by the membrane component. Hydrogen production is inhibited by acetylene but the degree of inhibition is dependent on the nitrogenase component ratio. The strongest inhibition is achieved at low MoFe protein/Fe protein ratios. The values are 4–5 at the component ratios giving the highest activity and increase at high MoFe protein/Fe protein ratios. CO inhibits acetylene reduction but has no effect on the hydrogen production. 相似文献
66.
67.
L Freysz A A Farooqui Z Adamczewska-Goncerzewicz P Mandel 《Journal of lipid research》1979,20(4):503-508
Arylsulfatases A, B, and C, beta-galactosidase, and acid phosphatase were assayed in neuronal, astroglial, and oligodendroglial fractions isolated from adult rabbit and beef brains. The specific activities of all acid hydrolases were lower in beef cells compared to rabbit cells. The lysosomal enzymes of the rabbit neuronal fraction showed 10--25 time higher activities than the oligodendroglial fraction and 5-fold higher activities than the astroglial fraction. In beef brain, the specific activities of these enzymes were similar in oligodendroglia and astrocytes but 4--10 times lower than in neurons. The low activity of arylsulfatase A and beta-galactosidase in oligodendroglial cells may suggest that the low turnover of cerebroside and sulfatide in myelin may be regulated in part by the enzymes that catalyze their degradation. 相似文献
68.
Abstract— Two NADPH-linked aldehyde reductases (alcohol:NADP+ oxidoreductase, EC 1.1.1.2) capable of reducing succinic semialdehyde to the anaesthetic Chydroxybutyrate have been purified from human brain to electrophoretic homogeneity. The first of these enzymes, which is typical of its category, is not specific for succinic semialdehyde and can reduce some aromatic aldehydes at a high rate. It is a monomer of molecular weight about 45,000 and is strongly inhibited by various hypnotics and anticonvulsants. The second enzyme is, in contrast, fairly specific for succinic semialdehyde. It is a dimer of molecular weight about 90,000 and is not inhibited by the hypnotics and anticonvulsants which inhibit the first enzyme. It is thus different from previously described aldehyde reductases from human brain. 相似文献
69.
J. Bilen M. E. Ittel C. Niedergang H. Okazaki P. Mandel 《Neurochemical research》1981,6(12):1253-1263
Two different preparations isolated from beef cerebrum have been used to compare the polyadenosine diphosphate ribose (polyADPR) polymerase activities in neuronal and glial nuclei: (1) nuclear suspensions (with or without DNase I treatment), and (2) 1 M NaCl nuclear extracts (soluble enzyme). The DNAse I treatment of nuclei and the solubilization of polyADPR polymerase by 1 M NaCl enhances the polyADPR polymerase activity. The polyADPR polymerase activity is similar in neuronal and glial nuclear suspensions, while the neuronal soluble enzyme activity is significantly higher than that of the glial soluble enzyme. Evidence is presented that the difference in soluble enzyme activities is not due to the effects of DNA or degrading enzymes. Some activating factor(s) seem to be present in neuronal soluble extracts, while both inhibiting and activating factor(s) seem to be present in glial soluble extracts. 相似文献
70.
Dr. I. Trebichavský M. Holub L. Jarošková L. Mandel F. Kovářů 《Cell and tissue research》1981,215(2):437-442
Summary The development of lymphoid populations in the omentum majus during the prenatal and postnatal life of the pig was studied. T lymphocytes, monocytes and mast cells were first found on the 40th day of gestation. B lymphocytes appeared on the 72nd day of gestation when the first macrophage aggregates were formed. Macrophages appeared to be the prerequisite for the formation of dense lymphatic areas (DLA's). At later stages T cells were observed only in the omentum of germfree pigs. DLA's of conventional pig omentum are filled exclusively with B cells. 相似文献