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941.
942.
By assuming the operational amplifier can be represented by a single-pole model, a very simple circuit has been developed to replace grounded inductors in ladder filters. The resulting active filters can be used at high frequencies and produce very little noise at their outputs. 相似文献
943.
944.
Fourteen patients with shortening of the oesophagus due to chronic reflux oesophagitis have been treated by a combination of an oesophageal lengthening procedure with a standard anti-reflux repair. Their ages ranged from 18 to 78 years and eight were male. Thirteen patients had a reflux stricture (with additional penetrating ulcer in six) and one had a columnar-lined oesophagus. A complete circular myotomy was performed just below the level of the aortic arch, in combination with a Belsey Mark IV anti-reflux repair. There were no deaths post-operatively but one patient required re-operation for haemorrhage and one underwent oesophageal dilatation before discharge. All patients have now been followed up for over 5 years. Nine patients have required no further treatment for their oesophageal problems, two required two early dilatations each, two required multiple dilatations and one required oesophageal resection for stricture. We suggest that this combination merits further evaluation in the management of patients with short oesophagus due to reflux. 相似文献
945.
946.
A comparative evaluation of the macrodilution method and the Alamar colorimetric method for the susceptibility testing of amphotericin B, fluconazole, and flucytosine was conducted with 134 pathogenic yeasts. The clinical isolates included 28 Candida albicans, 17 Candida tropicalis, 15 Candida parapsilosis, 12 Candida krusei, 10 Candida lusitaniae, 9 Candida guilliermondii, 18 Torulopsis glabrata, and 25 Cryptococcus neoformans isolates. The macrodilution method was performed and interpreted according to the recommendations of the National Committee for Clinical Laboratory Standards (document M27-P), and the Alamar colorimetric method was performed according to the manufacturer's instructions. For the Alamar colorimetric method, MICs were determined at 24 and 48 h of incubation for Candida species and T. glabrata and at 48 and 72 h of incubation for C. neoformans. The overall agreement within +/- 1 dilution for Candida species and T. glabrata against the three antifungal agents was generally good, with the values for amphotericin B, fluconazole, and flucytosine being 85.3, 77.9, and 86.2%, respectively, at the 24-h readings and 69.3, 65.2, and 97.2%, respectively, at the 48-h readings. Most disagreement was noted with fluconazole against C. tropicalis and T. glabrata. Our studies indicate that determination of MICs at 24 h by the Alamar colorimetric method is a valid alternate method for testing amphotericin B, fluconazole, and flucytosine against Candida species but not for testing fluconazole against C. tropicalis and T. glabrata. For flucytosine, much better agreement can be demonstrated against Candida species and T. glabrata at the 48-h readings by the Alamar method. Excellent agreement within +/- dilution can also be observed for amphotericin B, fluconazole, and flucytosine (80, 96, and 96%, respectively) against c. neoformans when the MICs were determined at 72 h by the Alamar method. 相似文献
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948.
Phillips D. Allen; Carlisle Cynthia S.; Hautala Robert; Larson Richard 《Canadian Metallurgical Quarterly》1985,77(4):408
Analyzed the relationship of teacher personality as measured by the 16PF to teacher behaviors in physical education as measured by a physical education teacher assessment instrument. Teacher behavior data were obtained from 18 physical education teachers in 3 junior high schools, 5 middle schools, and 6 elementary schools who volunteered to teach a 10-lesson beginning volleyball unit using their own individual teaching styles. Eight students were randomly selected from each teacher's class (n?=?144). Results indicate the primary personality traits of assertiveness, expediency, questioning, imaginativeness, genuineness, confidence, and experimenting related significantly to many important teacher and student behaviors observed in a typical physical education class. Teachers who scored high on these personality traits tended to exhibit a higher level of knowledge, utilized objectives and testing more effectively, and were more flexible and appropriate in their instruction. They also provided more planned instruction and more positive feedback. Teachers who scored high in assertiveness, questioning, and imaginativeness tended to provide their students with more time on task and a higher quality of practice time. Students of teachers who scored high in independence, assertiveness, questioning, and imaginativeness learned more than did students of teachers who were low in these personality traits. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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950.