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41.
This paper reviews two studies that evaluated the school feeding program in Jamaica. The first examined 115 children aged 12-13 y who were enrolled in three classes in a poor, rural school. One class was served the standard school meal at 0900 whereas the other two classes served as controls. The outcome variables included school achievement, attendance, and weight gain. After one semester, the class receiving the meal showed improved arithmetic scores and school attendance compared with the control classes; however, they showed no weight gain. The academic improvement remained significant after school attendance was controlled for. It was therefore hypothesized that the gains in arithmetic resulted from the alleviation of hunger in the classroom. The other study, conducted in a metabolic ward, examined the effects of missing breakfast on cognitive function in 90 children aged 9-10 y and of differing nutritional status. Using a crossover design, the investigators tested each child on two mornings 1 wk apart, once after serving them breakfast and second without. Breakfast, consisting of the school program meal, was served at 0800. When severely malnourished, stunted, or wasted children received no breakfast, their performance in various cognitive tests deteriorated. These results indicate that alleviation of hunger was one of the mechanisms by which school feeding improved academic achievement in the previous study. Undernourished children are more likely to benefit from school feeding programs than are adequately nourished children.  相似文献   
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Two experiments investigated the effects of simultaneous sinusoidal vibration in the vertical and lateral axes on ratings of discomfort in human Ss in a simulated passenger aircraft. In Exp I, each of 24 undergraduates experienced each of 10 levels of lateral frequency of vibration at 10 levels of vertical frequency and rated the discomfort produced on a 9-point, unipolar scale. Both vertical frequency and lateral frequency, as well as the interaction between the two, significantly affected the subjective ratings. In Exp II, 72 undergraduates experienced 1 of 4 levels of vertical frequency at each of 4 levels of vertical amplitude combined with 16 lateral frequency and amplitude conditions. Not only did the 4 major variables studied significantly affect ratings of discomfort, but the interactions between them had significant effects as well. Results of the 2 studies strongly suggest that there are effects on discomfort that occur when Ss are vibrated in several axes at once that cannot be assessed with research using vibration in only one axis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Eighty-five cases of atypical schizophrenia were compared with 200 of schizophrenia, 100 of bipolar (mania), and 225 of unipolar (depression) affective disorder. Comparisons were made on the basis of sex, age at admission, precipitating factors, outcome, and a family history of schizophrenia or of affective disorder. The atypical schizophrenia differed remarkably from the schizophrenia and most closely resembled the bipolar affective disorder when allowance was made for a younger age at onset and a higher frequency of precipitants. An analysis of symptoms verified the predominance of schizophrenic features in the atypical schizophrenia, but also showed a high percentage (80%) of patients who had one or more manic symptoms at index admission. It is concluded that great care should be taken in diagnosing schizophrenia in a patient who also has manic symptoms.  相似文献   
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Pimiento pepper (Capsicum annum L.) seed oil was shown to contain 66–71% linoleic acid with smaller quantities of 16 and 18 carbon saturated and monounsaturated fatty acids. Neither geographical location nor location within pimiento processing plants influenced the level or composition of the seed oil. Two varieties of bell-type peppers were shown to have essentially the same seed oil composition as that of pimientos. Oil extracted from the fruit wall and placenta of pimientos was red and contained high levels of linolenic and small quantities of very long chain polyunsaturated fatty acids. Journal Series Paper No. 462, Georgia Experiment Station, Experiment, Ga.  相似文献   
48.
An important general question in neurobiology concerns the development and expression of the rich context of neuronal phenotypes, especially in relation to the diverse patterns of connectivity. Organotypic cultures of brain slices may offer distinct advantages for such studies if such a preparation survives, maintains a wide diversity of neuronal phenotypes and displays appropriate synaptic connections between regions. To address these requirements, we utilized long-term organotypic cultures of intact horizontal slices of rat forebrain and midbrain and assessed a variety of markers of phenotype in combination with functional tests of connectivity. This explant preparation displayed a distinct viability requirement such that the greatest explant survival was seen in slices taken from pups of less than postnatal day 7 and was independent of N-methyl-D-aspartate channel blockade. The anatomical features of the major brain regions (e.g., neocortex, striatum, septum, hippocampus, diencephalon and midbrain) were observed in their normal boundaries. The presence of cholinergic and catecholaminergic neurons was demonstrated with acetylcholinesterase histochemistry and tyrosine hydroxylase immunohistochemistry. Labelled neurons displayed multiple, regionally-appropriate cytoarchitectures and, in some cases, could be seen to project to brain regions in a manner quite similar to that seen in vivo. Finally, the direct demonstration of spontaneous and evoked interregional excitatory synaptic transmission was made using whole-cell patch-clamp recordings from striatal neurons which revealed an intact glutamate-using corticostriatal pathway. This simple explant preparation appears to contain a rich diversity of neuronal types and synaptic organization. Therefore, this preparation appears to have several distinct advantages for basic neurobiologic research since it combines long-term culture viability and many features of mature brain including complex interregional neuronal systems.  相似文献   
49.
A new procedure was developed for the purification of the terminal oxygenase component (ISPNAP) of naphthalene dioxygenase. From a five liter culture of Escherichia coli JM109(DE3)(pDTG121), 91 mg of pure protein were obtained with a specific activity of 2.48 mumol/ min/mg protein. ISPNAP was crystallized in the rhombohedral space group R32 with cell dimensions of a = b = 179.2 A; c = 322.5 A in the hexagonal setting. The crystals are brown, indicating the presence of an intact Rieske iron-sulfur center. Problems with non-isomorphism between native data sets necessitated the preparation of a selenomethionine-substituted protein. Complete replacement of methionine with selenomethionine was achieved and the purified protein had a specific activity almost identical to native ISPNAP. Crystals from this preparation belong to the same space group and have similar cell dimensions to native ISPNAP.  相似文献   
50.
C3 nephritic factor (C3NeF) interacts with native C3 and B in the absence of D to generate a C3 convertase containing an uncleaved form of B. Dose response studies with C3NeF and B, respectively, revealed incremental C3 inactivation without loss of B. These findings are in agreement with the previous isolation from such reaction mixtures of a 10S complex containing haemolytically inactive C3 and active B and manifesting C3 convertase activity. Functional contamination of C3 with C3b was negated by demonstrating that pretreatment of C3 with C3bINA had no effect on its subsequent interaction with B and C3NeF to generate C3 convertase activity, while pretreatment of C3b eliminated its effective interaction with B and C3NeF. Relatively higher concentrations of C3bINA present during interaction of C3, B and C3NeF suppressed C3 inactivation, indicating its dependence on amplification by utilization of the initial C3b generated. Trace quantities of D were not found by functional analyses of C3, B and C3NeF and pretreatment of these proteins with a concentration of DFP sufficient to suppress D activity had no effect on their effective interaction. The introduction of D to mixtures of C3NeF, B, and C3 resulted in B clevage and more efficient expression of C3 convertase function as defined by a reduced requirement for C3NeF.  相似文献   
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