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排序方式: 共有1319条查询结果,搜索用时 15 毫秒
981.
982.
WH Drinkenburg EL van Luijtelaar WJ van Schaijk AM Coenen 《Canadian Metallurgical Quarterly》1993,54(4):779-783
Aberrant transients in the cortical electroencephalogram of rats of the epileptic WAG/Rij strain were studied by means of spectral analysis. The EEG of rats of this strain contains, besides normal sleep spindles, high-voltage spiky phenomena, epileptic spike-wave discharges, and deviant intermediate stage. Spectral analysis of these transient phenomena shows that some features, like their peak frequency, are alike, but that they differ in other spectral characteristics, as in the first harmonic of the peak frequency and in the domain of the high frequencies. The results provide arguments for the view that spike-wave discharges might be considered as unique aberrant phenomena, presumably related but dissimilar to the high-voltage spiky phenomena and intermediate stage. Next to this, spectral analysis was used to study the intraphenomenal dynamics of spike-wave discharges. The peak frequency was found to decrease monotonously from about 10 Hz at the beginning of the spike-wave discharge to about 8 Hz at the end. Other spike-wave discharge frequency bands showed an intraphenomenal increase followed by a decrease. These time-variant EEG dynamics in spike-wave discharges might correlate with the cognitive disturbances during absence seizures in man. 相似文献
983.
Bronchiolitis obliterans has been described in adults with rheumatoid arthritis, particularly in association with D-penicillamine treatment, but to our knowledge has not been reported in juvenile rheumatoid arthritis (JRA). We describe a 12-year-old girl with JRA who developed bronchiolitis obliterans after a 6-month course of intramuscular gold. She presented with severe obstructive airway disease (FEV1, 17% predicted) unresponsive to bronchodilators, without obvious pathology on chest radiograph. Despite aggressive immunosuppressive therapy and eventual lung transplantation, she died 3 1/2 years after her initial diagnosis of JRA. Although rare, bronchiolitis obliterans must be considered in the differential diagnosis of respiratory distress in children with JRA. 相似文献
984.
The ability of human blood serum for inactivating tissue thromboplastin is established to be due to the presence of two inhibitors: thermolabile inhibitor characterized by a progressive effect and thermostable one having an instant effect. Thromboplastin inhibition by the thermolabile inhibitor is partial, whereas inhibition by the thermostable one is completely reversible. In the latter case inhibition is intermediate character, between the competitive and incompetitive one. The inhibitory activity is found in Cohn's fraction V, is removed during DEAE-cellulos chromatography and gel chromatography with the first portions of eluating liquid. 相似文献
985.
Potter renal nonfunctional syndrome is an association of facial and limb anomalies, pulmonary hypoplasia, and fetal renal anomalies which lead to marked oligohydramnios, including renal agenesis (true Potter syndrome), renal cystic dysplasia, and obstructive uropathies. Some infants survive long enough to develop severe respiratory distress secondary to pulmonary hypoplasia. The underlying renal disease is often noted only at autopsy. We studied four infants, only one of whom had clinical signs of the renal nonfunction syndrome. Portable voiding cystourethrography revealed a tiny bladder in three infants with cystic dysplasia kidneys (two of these infants had reflux into unused ureters). Bladder hypertrophy and vesicoureteral reflux secondary to posterior uretral valves were noted in the fourth infant. 相似文献
986.
DH Moore LF Chasseaud JD Lewis PC Risdall EL Crampton 《Canadian Metallurgical Quarterly》1976,14(3):183-187
The problems in early diagnosis of endometrial cancers are not sufficiently solved. Only atypical bleeding with subsequent curettage will result in success. At this time progredient carcinomas are frequent and the chance of recovery is small. Therefore a screening program of early diagnosis by small biopsy is developed and clinically proved. 相似文献
987.
EL Chambers 《Canadian Metallurgical Quarterly》1976,197(1):149-154
The presence of at least 2.5 mM Na during the first several min after insemination is required for the activation of sea urchin eggs. Of those chemical species examined that exist entirely as cations, and which did not activate the unfertilized egg, only Li substitutes for Na. Ammonium and other amines, with pKa values between 9 and 10.8, in the complete absence of Na (a) can induce nuclear activation of unfertilized eggs, and (b) permit the development of the early fertilized egg through the stage that normally requires Na. 相似文献
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