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Farley D 《FDA consumer》1994,28(1):12-17
Certain heart valves manufactured by Shiley, Inc., turned out to have increased fracture rates. Alerting doctors and patients to this problem has changed the way FDA expects manufacturers to communicate significant risks with medical devices. 相似文献
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MK Barry JA van Heerden DR Farley CS Grant GB Thompson DM Ilstrup 《Canadian Metallurgical Quarterly》1998,22(6):599-603; discussion 603-4
We currently recommend excision of adrenal incidentalomas > or = 4 cm in size and all hormonally active tumors. The optimal management and follow-up of smaller nonfunctioning tumors are controversial. The aim of this study was to determine the clinical outcome of a well defined population of patients with incidentalomas followed without operative intervention. The study group comprised 231 patients, identified from the records of abdominal or thoracic computed tomographic (CT) scans performed between 1985 and 1989. The primary outcome variable analyzed was survival. Follow-up was obtained by office records, telephone contact, or letter. There were 101 male and 130 female patients with a mean age at diagnosis of 64 years (range 5-86 years). Most adrenal tumors were unilateral (right 113; left 98); 20 were bilateral. Mean tumor size was 2 cm (range 1-6 cm). In nine (4%) patients the tumor was > or = 4 cm. Follow-up [mean 7 years; range 1 month (patient died) to 11.7 years] was complete in 224 (97%) patients. Ninety-one (39%) patients had one or more additional CT scans performed during the follow-up period, with only four patients demonstrating a > 1 cm increase in the size of the adrenal mass. Surgical excision of these four lesions identified benign pathology. Eighty-one (35%) patients died of conditions unrelated to adrenal pathology. No patient developed subsequent adrenal hyperfunction or adrenal malignancy. Within the context of our guidelines, conservative management of adrenal incidentalomas considered benign or nonfunctioning at diagnosis is appropriate. Additional information provided by repeat CT scanning appears to confer limited benefit. This study does not support laparoscopic removal of small, nonfunctional adrenal tumors, as has been suggested. 相似文献
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R Farley 《Canadian Metallurgical Quarterly》1977,14(4):497-518
Sociologists and urban commentators often portray metropolitan areas as highly segregated by social class and race. We measured the extent of socioeconomic residential segregation in urbanized areas of the United States in 1970, determined whether cities were as segregated as suburban rings, and compared levels of socioeconomic and racial residential segregation. We found moderate levels of residential segregation and socioeconomic groups. Levels of social class segregation varied little from one urbanized area to another and were about the same in central cities and suburban rings. Racial residentail segregation was much greater than the segregation of social classes within either the black or white communities. The extent of racial residential segregation does not vary by educational attainment, occupation, or income. 相似文献
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The Likens-Nickerson concurrent steam distillation-solvent extraction apparatus was used to obtain an essence from malt extract. The essence was submitted to combined gas chromatography-mass spectrometry (g.c.-m.s.), to examination by sulphurspecific and nitrogen-specific detectors, and to sensory evaluation of the components eluted from gas chromatographic capillary columns. Some 33 compounds were identified by direct examination by g.c.-m.s., another 14 by trapping and re-injection, which provides an efficient method of concentration, and a further six, which had not been previously identified due to interference from the solvent peak, by the use of charcoal adsorption traps. Results indicate that several compounds need to be combined to simulate malt flavour. The odour contributions of several components are discussed. 相似文献
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The addition of extra light-alone or rotation-alone presentations to sequences of light-rotation pairings reduced the associative suppression of phototaxic behavior for the nudibranch Hermissenda. Training-induced changes in Type B photoreceptor light responses were found to parallel the training-induced behavioral changes in the intact animal. The decremental effects of the degraded contingency treatments upon neural and behavioral changes normally occasioned by light-rotation pairings reflected two processes. One factor was the increased stimulation frequency entailed by degraded contingency training. The second factor reflected the specifically unpaired character of the added light-alone or rotation-alone presentations, independent of frequency changes. The attenuation of phototaxic suppression was not because of a general habituation process or adaptation to the effects of either visual or vestibular stimulation. Instead, attenuation seemed to reflect a local interference effect of interspersed unpaired stimuli. The present experiments demonstrate a sensitivity to stimulus contingencies for Hermissenda similar to that of many vertebrates and indicate that contiguity and contingency relations are both encoded and stored in the Type B photoreceptors. The results indicate that similar neurophysiological mechanisms are involved. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Hermissenda's neural and behavioral changes produced by light-rotation pairings were assessed as a function of the temporal relations between visual and vestibular stimulation. The results of in vitro simulations of conditioning indicated that simultaneous pairings (synchronous onsets and offsets of light and caudal hair cell stimulation) resulted in significantly greater cumulative depolarization of Type B photoreceptors than did either forward (light preceded hair cell stimulation) or backward (hair cell stimulation preceded light) pairings. Further experiments revealed that the attenuation of cumulative depolarization produced by the forward and backward pairings reflected the asynchrony of stimulus offsets that characterize these conditioning sequences, rather than their onsets. Analogous behavioral experiments revealed that intact animals trained with forward or backward pairings exhibited significantly less conditioning than those trained with simultaneous pairings. Strong parallels between the magnitude of cumulative depolarization from in vitro conditioning studies and the behavioral results for intact animals were also observed in experiments in which stimulus onset synchrony was held constant but offsets were made asynchronous, and vice versa. Thus Hermissenda exhibits a sensitivity to the temporal arrangement of light and rotation, and the results of behavioral conditioning can be predicted accurately from the outcome of in vitro conditioning of the isolated nervous system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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