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961.
Two chronic haemodialyzed patients with digitalis intoxication are reported. One of them took digoxin 0.25 mg three times daily for an unknown period and the other took digitoxin 0.1 mg twice daily for two weeks. The symptoms of intoxication were mainly concealed by uremic syndrome. The diagnosis was established by noticed sinus bradycardia, first- and second-degree atrioventricular block in ECG and the determination of sera levels of glycosides (serum digoxin concentration was 7.36 ng/ml, serum digitoxin concentration was 46.5 ng/ml) in both cases. Considering the probable long elimination period of digitalis and the potentially life-threatening situation the patients were given digoxin-specific antibody (Fab) fragments with potassium replacement therapy. The symptoms disappeared within a few hours after therapy, side effects and rebound toxicity did not develop. In connection with these cases the aim of this report is to publish a method which can reverse the life-threatening digitalis intoxication in patients suffering from renal failure as well. As to the above method, the authors have not found any similar case reports in the Hungarian medical literature.  相似文献   
962.
This contribution describes the preparation, based upon a chemically amplified novolak resist (CAR), electron beam lithography, and ECR plasma etching, of structures with a high aspect ratio (10∶1) and lateral dimensions in the sub-micrometer range (150nm–300nm) which may serve as collector surfaces for sub-μm dust particles in a space experiment.  相似文献   
963.
This paper deals with the muscle force of the cervical spine in patients with cervical syndrome compared to the muscle activity in non-patients. It has thus been observed that both the flexors' and the extensors' force of the cervical spine is much greater in non-patients (the flexors' P < 0.01 and the extensors' P < 0.01). The precise measurements having been carried out by a dynamometer. The groups being tested comprised 50 persons each, 25 men and 25 women. The average age of the patients group was 43.1 years, namely between 21 and 57 years, while that of the non-patients group was 42.3 years, between 24 and 56 years. As regards the professional engagement of both groups and, accordingly, the strain on the cervical spine and the corresponding musculature, they were approximately the same.  相似文献   
964.
965.
An improved accelerated cable life test is described. Through the use of programmable logic controllers (PLCs), very precise and consistent control of the accelerated aging process has been achieved. A computer has been utilized to make continuous real-time acquisition and storage of key operating parameters possible. This precise control and monitoring methodology has permitted the study of the synergistic effects of voltage and temperature on the accelerated aging of full-sized cables in the laboratory  相似文献   
966.
The authors present the basic philosophy, construction, design features, and test results of a new fault locating system. This fault locating system helps to shorten the time required for restoration of service after the occurrence of a busbar fault in an air-insulated distribution substation. Recent optical and electronic technologies allow the design of a highly accurate and compact fault locating system which consists of optical current detectors using the Faraday effect and a fault locating processor using a digital data processing technique. The fault location is carried out by discriminating between the directions of zero-sequence currents. Through various tests and field operations, it has been confirmed that the system has sufficient performance for practical applications  相似文献   
967.
Two laboratory-scale plasma reactors, an alternating current (AC) energized ferroelectric (high dielectric ceramic) packed bed reactor and a nanosecond pulsed corona reactor, were constructed. This study was done to develop baseline engineering data to demonstrate the feasibility of the application of plasma reactors to the destruction of various volatile organic compounds (VOCs) at PPM levels. Complete destruction was obtained for toluene. Conversions of methylene chloride at 95% and trichlorotrifluoroethane (known as CFC-113) at 67% were achieved for the plasma reactors used. The conversion was dependent on the mean electron energy in the reactor and was also related to how strongly halogen species were bonded with carbon  相似文献   
968.
A fault section detection system that uses optical magnetic field sensors and instantly detects the section in which a ground fault occurred was developed for 66 kV underground multiterminal systems having Y-branch joint boxes. The optical magnetic field sensor, which is based on the Faraday effect in Bi-doped YIG ((BiYbGd)3Fe5O12) having a large Verdet constant, detects cable conductor currents of 0 to 2000 A with high precision with the use of a laminated magnetic ring core of silicon steel plates. Sensors and a fault section detector/indicator of a system are connected with optical fibers capable of nonrepeated transmission of over 6 km  相似文献   
969.
Cancer statistics, 1993   总被引:1,自引:0,他引:1  
  相似文献   
970.
Changes in the GABAergic system after chronic treatment with bicuculline were examined in two strains of inbred rats, Fischer 344 (F344) and Lewis (LEW). Rats received an IP injection of either bicuculline (2 mg/kg) or vehicle once a day for 12 days. After this chronic treatment, the effects of diazepam (1 mg/kg, IP) and pentobarbital (20 mg/kg, IP) on bicuculline-induced convulsions were measured. Bicuculline was acutely infused into a tail vein at 0.0415 mg/min, and the infusion was terminated when rats showed seizure. Following the chronic bicuculline treatment, the anticonvulsant effect of diazepam, but not of pentobarbital, was significantly reduced as compared to its effect following chronic vehicle treatment in both strains. Both diazepam and pentobarbital showed a significant difference in anticonvulsant effects between strains (F344 > LEW). The hypnotic effects of muscimol, barbital, pentobarbital, and ethanol following chronic bicuculline treatment were examined. There was no significant difference in sleep time induced by these drugs between bicuculline- and vehicle-treated rats. These results suggest that the attenuation of diazepam's anticonvulsant effect after chronic bicuculline treatment may result from functional changes in benzodiazepine receptors and that the anticonvulsant effects of diazepam and pentobarbital may be influenced by genetic factors. Moreover, the hypnotic effects of several drugs tested are apparently not affected by chronic bicuculline treatment.  相似文献   
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