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141.
Rats were given suction lesions of the presumptive frontal cortex on embryonic day 18 (E18) and subsequently tested, as adults, on tests of spatial navigation (Morris water task, radial arm maze), motor tasks (Whishaw reaching task, beam walking), and locomotor activity. Frontal cortical lesions at E18 affected cerebral morphogenesis, producing unusual morphological structures including abnormal patches of neurons in the cortex and white matter as well as neuronal bridges between the hemispheres. A small sample of E18 operates also had hydrocephaly. The animals with E18 lesions without hydrocephalus were behaviorally indistinguishable from littermate controls. The results demonstrate that animals with focal lesions of the presumptive frontal cortex have gross abnormalities in cerebral morphology but the lesions leave the functions normally subserved by the frontal cortex in adult rats unaffected. The results are discussed in the context of a hypothesis regarding the optimal times for functional recovery from cortical injury.  相似文献   
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The effect of food-related environmental factors on the formation of tyramine byLactobacillus curvatus LTH 972 was investigated in liquid culture supplemented with tyrosine. The highest concentrations of tyramine (up to 201 mg/l) were formed at 30 °C, pH 5.2 and at a water activity (aw) of 0.97. At lower temperatures and at higher pH- and aw values the reaction slowed down but was still clearly detectable. Glucose, nitrate and nitrite had no effect at concentrations applied in sausage fermentations. The strain was able to form tyramine from tyrosine-containing di- and tripeptides in phosphate buffer. Therefore, in proteinaceous substrates an increased formation of tyramine cannot be excluded when ongoing proteolysis creates precursors, as is the case in the presence of proteolytic micro-organisms.
Die Bildung von Tyramin durchLactobacillus curvatus LTH 972
Zusammenfassung Der Einfluß von Lebensmittel kennzeichnenden ökologischen Faktoren auf die Bildung von Tyramin durchLactobacillus curvatus LTH 972 wurde in Flüssigkultur mit Tyrosinzusatz untersucht. Höchste Konzentrationen an Tyramin (bis zu 201 mg/l) wurden bei 30 °C, pH 5,2 und aw 0,97 gebildet. Bei niedrigeren Temperaturen (15 °C) sowie höheren pH- und aw-Werten wurde eine verlangsamte, aber dennoch deutliche Tyraminbildung beobachtet. Glucose, Nitrat und Nitrit hatten in Konzentrationen, wie sie bei der Rohwurstherstellung üblich sind, keinen Einfluß. Eine Tyraminbildung aus Di- und Tripeptiden mit Tyrosylresten wurde in Phosphatpuffer beobachtet. In proteinreichen Substraten ist daher eine verstärkte Tyraminbildung nicht auszuschließen, wenn bei ablaufender Proteolyse Präkursoren gebildet werden, wie es z. B. bei Anwesenheit proteolytischer Mikroorganismen möglich ist.
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146.
An interactive program for the statistical analysis of cell survival curves by a linear regression approach is described. It allows for the computational determination of the linear part of a cell survival curve and the determination of a common slope estimate in the presence of repeated experiments for a particular cell strain with the appropriate variance estimates and confidence intervals.  相似文献   
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The structure of constructive thinking and the development of an instrument for measuring it, the Constructive Thinking Inventory (CTI), were discussed. Scales were derived from a factor analysis of an item domain of people's everyday automatic thinking. When the CTI and other tests were factor analyzed, separate intellective and nonintellective factors were found, with the CTI loading more strongly on the nonintellective factor than any other test. Only measures of IQ loaded on the intellective factor. The global constructive thinking scale correlated significantly with success in work, love, social relationships, and in maintaining emotional and physical well-being, but not with academic achievement, the only criterion with which the measures of IQ correlated strongly. The patterns of correlations between the CTI scales and the various criteria as well as the factor analysis demonstrated that the construct of constructive thinking is differentiated as well as integrated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
148.
Results from a series of small scale (using the DIN 53 436 tube furnace) and large scale experiments (using the IEC 60332-3 rig) are presented for two types of power transmission cables used in buildings. The results are unique in that they catalogue the production of a wide variety of organic and inorganic species under different fire conditions. The experiments were conducted to provide input to an LCA model and the specific organic species studied in detail have been chosen based on the information required by the LCA model.During the process of this study it became apparent that information concerning quantitative organic species evolution from cable fires is lacking in the open literature. This paper aims to provide such information for two specific sets of fire conditions, i.e., a well-ventilated and a vitiated cable riser fire.  相似文献   
149.
This article presents a framework for understanding aesthetic experience, with special reference to the natural environment. The framework entails 2 broad perspectives. First, from a functional perspective, aesthetic experiences are analyzed in terms of biological, sociocultural, and psychological systems of behavior; succinctly stated, objects are experienced aesthetically if they activate cognitive representations of response patterns that do or did contribute to the survival or enhancement of the species, society, or the self. Second, from the perspective of mediating mechanisms, the cognitive processes that enable aesthetic experiences are examined. The mechanisms discussed range from simple sensory processes to the activation and transformation of complex schemes. To the extent that cognitive representations of behavioral systems are flexible and subject to elaboration and refinement, aesthetic experience is a creative, skillful act. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
150.
Austenitic stainless steel specimens have been examined by positron-lifetime measurements at various stages until failure during fatigue tests at constant stress or plastic strain amplitudes. A positron-source-detector assembly has been mounted on the servohydraulic testing machines that allowed truly non-destructive positron annihilation studies without removing the specimens from the load train. Positrons were generated by a 72Se/72 As source with a maximum activity of 0.9 MBq (25 μCi). The average positron lifetime has been determined by a β+ − γ-coincidence applying a simplified data evaluation procedure. Under constant stress or plastic strain amplitudes early stages of fatigue damage could be detected. The strong increase of the average positron lifetime already during the first 10% of fatigue life could be related to the fatigue life of the specimens. Issues of lifetime prediction by positron annihilation measurements are discussed.  相似文献   
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