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691.
692.
The pattern of gangliosides in membranes of erythrocytes was examined in healthy donors, in acute schizophrenics without neuroleptic treatment and in alcohol-dependent patients. 7 different gangliosides could be detected after extraction, purification by column chromatography and fractionation by TLC. Healthy donors were characterized by the following pattern of gangliosides: GX = 5.8%, GT1b = 6.7%, FucGD1b = 5.2%, und GD1a = 12.6%, GD3 = 9.2%, SPG = 43.5% and GM3 = 17.0%. In schizophrenic patients the GM3- and GD3-fraction were increased. No difference was found between the control group and the alcoholics.  相似文献   
693.
Three months after anticonvulsive regulation by means of the spasmolytic agent Convulsofin, a 46-year-old man suffered severe hepatosis, and when the preparation was discontinued he suffered a severe cerebral dysfunction. The clinical picture is interpreted as being "similar to the Reye syndrome", and distinctions between this and previously reported cases are noted. There has been very little observation of such complications among adult patients.  相似文献   
694.
  总被引:1,自引:0,他引:1  
The effects of chronic intraventricular infusion of leupeptin, a potent inhibitor of thiol proteinases, were tested on ingestive behaviors, escape and avoidance conditioning, and spatial memory in rats. The drug did not detectably influence feeding, drinking, body temperature, or the latency to escape from a mild footshock or inhibitory avoidance behavior. However, rats treated with leupeptin made numerous errors ( reentries ) in an eight-arm spatial maze. These results are interpreted as supporting the hypothesis that calcium-activated thiol proteinases are involved in the formation of certain types of memory.  相似文献   
695.
Objective: This study examines age-differential association patterns between intentions, planning and physical activity in young and middle-aged individuals. The effectiveness of planning to bridge the intention–behaviour gap is assumed to increase with advancing age. We explore the use of behaviour change strategies that include selection, optimisation and compensation (SOC) as underlying mechanisms for age differences. Methods: In N = 265 employees of a national railway company (aged 19–64 years), intentions, planning, SOC strategy use and physical activity were assessed at baseline (Time 1) and again 1 month later (Time 2). Hypotheses were tested in two different path models. Results: Age moderates the extent to which planning mediates the intention–behaviour relation due to an increasing strength of the planning–behaviour link. As a possible psychological mechanism for these age differences, we identified SOC strategy use as a mediator of the age by planning interaction effect on physical activity. Conclusion: These findings suggest differential mechanisms in behaviour regulation in young and middle-aged individuals.  相似文献   
696.
  总被引:1,自引:0,他引:1  
After repeated exposure to receptive and nonreceptive females, male golden hamsters were tested for olfactory preferences in a four-choice olfactometer. Males discriminated between the odor of anesthetized females in different stages of their estrous cycle when the airstreams carrying the stimulus odors were diluted. Previous failures to demonstrate such an ability were probably due to ceiling effects resulting from laboratory testing. Males preferred the odor of females on the day before receptivity (a day coincident with maximal scent marking by the female) and least preferred the odor of females on diestrus-1 (the day on which females attacked and chased males during pretesting encounters). Detection and quick response to an impending estrus would be especially important for males of a solitary and promiscuous species in which there is a first male mating advantage.  相似文献   
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We report here on a pressure-induced phase transition in nanocrystalline La-deficient perovskite oxide, synthesised through the sol–gel technique, using Mössbauer spectroscopy, electrical resistivity and X-ray diffraction measurements at room temperature. At ambient pressure, the high-spin Fe3+ ion is distributed in two different environments. Below 0.6 GPa, a sudden dip in the resistivity curve and a single-environment Fe3+ doublet in the Mössbauer pattern are indicative of lattice compaction. A high-spin to low-spin Fe3+ transition at 2.1 GPa, and an orthorhombic to monoclinic structural transformation at 4.9 GPa, as revealed through Mössbauer patterns, are also associated with sudden dips in the electrical resistivity. X-ray diffraction patterns support the results.  相似文献   
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