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51.
A J Klein 《Ear and hearing》1989,10(1):50-57
Hearing aids with signal processors use advanced circuitry to enhance speech recognition in noise. The effectiveness of these processors has not been well established. The purpose of this study was to evaluate performance on a speech recognition in noise task for listeners wearing a Zeta signal processor aid with the processor turned on and with the processor turned off. In addition, comparisons were made to performance while unaided and aided with a conventional hearing aid. A simple adaptive procedure and a psychometric function were the procedures used. Results for normal-hearing subjects indicate performance was usually better without a hearing aid. Performance when aided was similar for the processor on and the conventional aid. Performance in both of these conditions was clearly better than with the signal processor off. Although results for the hearing-impaired subjects varied widely, there was a trend for better performance with the conventional aid and with the signal processor on than for the signal processor off condition. 相似文献
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55.
P J Sulak G S Letterie C C Hayslip C C Coddington T A Klein 《Fertility and sterility》1987,48(3):493-494
In two patients with apparent PTO, as diagnosed by HSG and laparoscopy, tubal patency was restored by hysteroscopic cannulation of the tubal ostia, followed by direct lavage. Tubal resection and reanastomosis/reimplantation may not be necessary for all patients with apparent PTO. 相似文献
56.
Inversion lateral ankle trauma: differential diagnosis, review of the literature, and prospective study 总被引:1,自引:0,他引:1
M Perlman D Leveille J DeLeonibus R Hartman J Klein R Handelman E Schulz S Wertheimer 《The Journal of foot surgery》1987,26(2):95-135
This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate. 相似文献
57.
78 geriatric patients predominantly suffering from cardiocerebrovascular diseases (stroke, heart insufficiency) and lesions respectively operations of the locomotion system (fractures, arthroses) were admitted in 1987 from acute hospitals for after-treatment (short-term care). 35 (= 45%) of them (average age 80 (61-92) could be discharged after 63.5 days on average, 11 died from intercurrent complications, 9 remained for long-term care as inrehabilitable. Besides other concomiting troubles mainly cardiac and circulation affections were present in the majority of patients. Their identification (a. o. by means of ultrasonic methods) and therapy also means a secondary prevention of cerebral as well as of fall and injuries inducing risk factors. The results confirm the principal rehabilitation chance of multimorbid geriatric patients by use of the diagnostic and therapeutic special potential of geriatrics. 相似文献
58.
Transformation of immortal, non-tumorigenic osteoblast-like human osteosarcoma cells to the tumorigenic phenotype by nickel sulfate 总被引:5,自引:2,他引:3
Rani A.Shobha; Qu Da-Qin; Sidhu Maninder K.; Panagakos Fotinos; Shah Varsha; Klein Kenneth M.; Brown Nicholas; Pathak Sen; Kumar Suriender 《Carcinogenesis》1993,14(5):947-953
Epidemiological studies have indirectly linked compounds ofchromium, nickel and arsenic to human carcinogenesis. However,there is no evidence that metal compounds can transform humancells to the tumorigenic phenotype in culture. We show herethat exposure to 36 µM NiS04 for 4896 h resultsin transformation of an immortal, non-tumorigenic, osteoblast-likecell line, HOS TE85, to the tumorigenic phenotype. Continuouspassaging following treatment leads to the formation of a fewdense foci. The cells isolated and expanded from the foci aremorphologically transformed, and form anchorage-independentcolonies of the size and abundance comparable to that formedby Kirsten murine sarcoma virus transformed HOS TE85 cells.The transformed cells from tumors in nude mice, have enhancedlevels of plasminogen activators and have lost the ability toform model bone matrix on extended culture in the presence ofascorbic acid and ß-glycerophosphate. A number ofcell lines have been established from nude mouse tumors. Cytogeneticanalysis reveals 16 marker chromosomes and an aberrant chromosome16. This is the first report of the transformation of a humancell line to tumorigenic phenotype by a metal carcinogen. 相似文献
59.
C J Yeo K D Lillemoe A S Klein M J Zinner 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(8):1016-1018
Perforation of esophageal malignancy secondary to instrumentation is an uncommon but catastrophic complication. Esophageal perforation at the site of an obstructing esophageal malignancy precludes simple operative repair and mandates esophageal resection with reestablishment of gastro-intestinal tract continuity. In the past the standard surgical approach has involved transthoracic esophageal resection via thoracotomy. We have successfully treated four patients with perforated esophageal neoplasms by transhiatal esophagectomy and cervical esophagogastrostomy, thus avoiding thoracotomy in high-risk patients. We consider transhiatal esophagectomy an advantageous alternative in the management of selected cases of instrumental esophageal perforation adjacent to an esophageal malignancy. 相似文献
60.