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931.
In the past decade, speech-language pathologists have taken a leading role in the management of services for patients with oropharyngeal dysphagia. This article presents the historical perspective of this role, the rationale for assuming the responsibility, and suggests directions for continued involvement.  相似文献   
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Von Hlppel—Lindau (VHL) disease is a dominantly Inheritedfamillal cancer syndrome In which affected individuals havea greatly increased predisposition to the development of haemangloblastomasof the central nervous system and retina, renal cell carcinomaand phaeochromocytoma. The VHL gene has been mapped to chromosome3p25 -p26 by genetic linkage studies and we have previouslydemonstrated that the VHL gene is tightly linked to the D3S601locus (Zmax = 18.86 at  相似文献   
935.
There is some controversy about the role of long-term potentiation (LTP) in spatial learning. The authors have found that triggering generalized kindled seizures with stimulation of the perforant path disrupts spatial learning in the Morris water maze but that kindling per se does not affect spatial learning. It is suggested that abnormal electrical activity induced by high-frequency stimulation of the perforant path may have been responsible for the disruption of spatial learning previously attributed to LTP saturation.  相似文献   
936.

Literature

Journal abstracts  相似文献   
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Summary To verify the appropriateness of sphincterotomy as the treatment of choice of choledocholithiasis, since 1980 we have been using endoscopic retrograde cholangiopancreatographic (ERCP) manometry of the sphincter of Oddi (SO). This method allows direct investigation of SO motor activity and provides useful information regarding the presence of benign papillary stenosis (BPS). Thirty-four patients were investigated because the radiological examination indicated BPS might be present. Of these, 20 had common bile duct (CBD) stones, while the remaining 14 presented with biliarylike pain and one or more of the following: CBD dilation (larger than 12 mm); emptying of the ERCP contrast medium took longer than 45 min; abnormal liver function tests. Moreover, 8 healthy volunteers served as controls. Our results show that the incidence of SO motor anomalies is very low in the presence of choledocholithiasis, while it is substantial in patients with suspected SO dysfunction. These observations would suggest that, unlike the traditional view, BPS is rarely secondary to biliary lithiasis. Therefore, most of the sphincterotomies performed that are based on the assumption of underlying SO pathology should be considered unnecessary. Under these circumstances, the physiological role of a functioning SO has induced us to advocate sphincterotomy, surgical or endoscopic, in selected cases only.  相似文献   
939.
Summary Carbetimer, a new synthetic low molecular weight polyelectrolyte with a novel structure displayed antitumor activiy in a number of animal tumor model systems and in vitro investigations. Based on these findings it was brought to a phase I clinical trial in patients with advanced malignant disease after failure of conventional treatment or with no conventional treatment available. Forty-eight patients received 98 courses. The schedule was a one hour i.v. infusion every four weeks. The starting dose was 180 mg/m2 and dose escalation was performed according to a modified Fibonacci formula up to 16,690 mg/m2. At least three patients were treated at each dose level and each patient was eligible to receive repeat courses at the same dose, until progressive disease or dose-limiting toxicity intervened. No hematological toxicity was encountered. Some adverse effects such as reversible proteinuria, hypercalcaemia, pain at infusion site, nausea and vomiting and fatigue were seen partly in a dose-related manner but did not represent the maximum tolerated dose (MTD). The limiting toxicity at the highest dose level of 16,690 mg/m2 consisted of ocular symptoms (light flashes) accompanied by a modest decrease of blood pressure and nausea or vomiting during a one hour infusion. 16,690 mg/m2/1 hour was considered the MTD. There were four deaths on study, all considered diseaserelated. Fourteen patients had stable disease for more than two courses, which, however, could also be explained by the natural course of disease. No clear-cut antitumor responses were noted in our study center.The recommended dose for phase II trials derived from our results is 12,550 mg/m2/2 hours. However, with regard to experiences in other phase I studies, the subsequent phase II studies will be performed with a dose of 6,500 mg/m2.  相似文献   
940.
Reproduction was studied in male C57B/6 mice treated with contaminated soils from a 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) manufacturing site in Newark, New Jersey, and a metal scrap yard where equipment from the manufacturing site was recycled. The soils contained a wide variety of contaminants including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). Treated males were mated to females given decontaminated soil. No acute toxicity was observed in treated males. 2,3,7,8-TCDD (up to 90 g/kg) or 2,3,7,8-TCDD from the contaminated soils (up to 288 g/kg) had no adverse effect on reproduction when the male mouse was treated. However, treatment of males with soil from the 2,4,5-T manufacturing site was associated with a marked decrease in viable litters at whelping and a decrease in pup survival. This toxicity may be associated with TCDD in combination with other toxic compounds that are present on the soil.  相似文献   
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