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Background

The beryllium lymphocyte proliferation test (BeLPT), has become the principal clinical test for detecting beryllium sensitization and chronic beryllium disease. Uninterpretable BeLPT results can occur in a small but significant proportion of tests from poor lymphocyte growth (PG) or over proliferation of lymphocytes (OP). The clinical and laboratory causes of uninterpretable results are not known.

Methods

BeLPT data from the US Department of Energy‐supported Former Worker Screening Program were analyzed for a 10‐year period. Drivers of uninterpretable BeLPTs were investigated using multivariable models and classification techniques.

Results

Three participant attributes were significantly associated with PG, while OP showed no significant associations. Serum lot for the lymphocyte growth medium accounted for 21% of the variation in PG and 16% in OP.

Conclusion

Serum lots influence the likelihood of having uninterpretable BeLPT. To better understand uninterpretable results and possibly reduce their occurrence, additional laboratory‐related factors should be addressed.
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The purpose of this study was to evaluate the oral health status, treatment needs, and dental care utilization patterns of a Native American population aged 65-74 years. A random sample of 688 individuals was chosen and approached regarding participation in the study. Data were gathered through an interviewer-administered questionnaire and an oral examination. A total of 204 individuals completed all aspects of the study. Only one participant had all 28 natural teeth, while 58.3 percent were totally endentulous. Of the 85 dentate participants, almost 53 percent required at least one extraction. The average number of required extractions in the dentate subjects was three. Although 94 percent of the sample stated they had a usual source of dental care, 40.7 percent had not visited a dentist within the last five years. Multiple regression analyses were used to determine the factors associated with total number of teeth present among the dentate participants. Years of education and time since last dental visit were the two significant predictors (P less than .05) of number of teeth present. The higher the level of education, the greater the number of teeth in later life. The number of teeth present was inversely related to years since dental treatment. Compared to the results of the National Survey of Oral Health in US Employed Adults and Seniors, this Native American sample had a higher prevalence of endentulism and utilized dental services less often than a comparable age group in the US population as a whole.  相似文献   
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