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1.
Glomerular tip lesion is a newly described histopathological lesion characterized by a focal and segmental widening of the mesangial matrix without hypercellularity together with capillary dilatation, hyaline exudation on the inside of capillary walls and occurrence of vacuolized cells, localized to the peripheral segments of the glomerular tuft. Clinically, these patients have a pronounced nephrotic syndrome with slightly reduced renal function, but terminal renal failure is seldom seen, even after many years of disorder. Two characteristic case histories are presented. The classification of this lesion among the glomerular disorders is at present uncertain. It may represent a transitional form between minor lesion nephritis and focal segmental sclerosis, a separate disorder, or a functional lesion associated with high proteinuria. 相似文献
2.
Aluminum has been reported to inhibit long-term potentiation (LTP) following in vivo administration and decrease glutamate release following in vitro exposure. Because glutamate release is critical for synaptic transmission and the development and maintenance of LTP in the hippocampus, we examined the effects of aluminum chloride (AlCl3) on depolarization-induced glutamate release and LTP in rat hippocampal slices. The effects of AlCl3 on [14C]glutamate release were examined by incubation of slices in depolarizing (56 mM)K+ buffer solution in the absence or presence of 2 mM CaCl2. After 15 min depolarization, AlCl3 (100-1000 microM) did not significantly affect Ca(2+)-dependent [14C]glutamate release from slices, whereas a known Ca2+ channel blocker (100 microM CdCl2) decreased Ca(2+)-dependent [14C]glutamate release by approximately 50%. In contrast to a previous report, acute exposure to AlCl3 was without effect on depolarization-dependent glutamate release. LTP of the population spike (PS) in CA1 of hippocampus was induced by the delivery of stimulus trains to the stratum radiatum. LTP of the PS was observed in both control slices and slices bathed in solution containing 100 microM AlCl3. Neither the magnitude nor longevity (measured up to 1 h posttrain) of LTP distinguished control from aluminum-exposed slices. The lack of sensitivity in rat to the encephalopathic changes induced by aluminum, or methodological differences in exposure conditions may account for the lack of effect of aluminum on in vitro LTP in rat hippocampus. 相似文献
3.
在自然崩落法相关研究的基础上,探讨了自然崩落法放矿控制的排产优化问题;给出了正向优化和逆向优化的数学模型,为实现均匀放矿提供了一种理想的理论方法。对充分发挥自然崩落法的优越性和提高矿产资源的回收率具有重要的理论和现实意义 相似文献
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Six hooded crows (Corvus cornix) were trained in alternative simultaneous matching-to-sample and oddity-from-sample tasks with visual stimuli. Bird's ability to acquire the abstract same/different concept was investigated. For this purpose three stimulus sets of the following categories were used: color (black and white cards), shape (Arabic numerals "1" and "2"), and numerousness (heterogeneous arrays of 1 or 2 elements). These three sets were used for training successively and repeatedly; each time the stimulus set was changed for the next one after the criterion (80% correct or better over 30 successive trials) was reached with the previous one. The training procedure was repeated until the criterion could be reached for each of the three stimulus sets within the initial 30-50 trials. After that, the abstractness of the rule acquired by birds was tested. First, the "partial" transfer tests were conducted, which consisted in presentation of novel stimuli with familiar ones (numerals and arrays in the range from 1 to 4). At the final stage, only sets of novel numerals and arrays in the range from 5 to 8 were presented. The crows demonstrated successful transfer in all of these tests, including the test with absolutely novel stimuli (in the first 24 presentations: min 75.0%, p < 0.02; max 83.3%, p < 0.01). The level of correct choices did not differ from the baseline (p > 0.05). This allows us to conclude that birds are capable for formation of the abstract same/different concept. 相似文献
6.
RIa Vovin IIa Gurovich OF Eryshev SG Za?tsev AIu Magalif 《Canadian Metallurgical Quarterly》1977,77(5):743-749
The authors studied the effectiveness of out-patient treatment by Moditen-Deppt of 128 schizophrenic patients. A comparison of the previous remissions appearing during usual pharmacotherapy and remissions seen during Moditen-Depot treatment depicted statistically significant differences, indicating a distinct prevention of exacerbations due to this preparation, an increase in the duration and improved quality of remissions. Such improved remissions were expressed in lesser severity, in a decrease of psychopathological disturbances, changes qualified as a "mollification of a defect" and an improvement of some socio-clinical indices. 相似文献
7.
外流降膜板式蒸发器作为替代列管式蒸发器的新设备应用于氧化铝行业,其板片材质处于一个摸索选择的过程。本文就高合金不锈钢板片的失败事例进行分析,通过试验、试用,最终找到较为理想的材质。 相似文献
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针对德兴铜矿设备状态监测的实际情况,论述了矿山设备润滑磨损状态监测系统,利用VB语言结合SQL Senrer开发设备润滑磨损状态分析系统。 相似文献