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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.
  相似文献   
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The International Agency for Research on Cancer (IARC) evaluates causes of cancer with help from independent international experts in an open and transparent manner. Countries, research and regulatory agencies, and other organizations adopt IARC evaluations for communication of human cancer hazards, and for strategies to prevent cancer. Scientists worldwide endorse IARC cancer evaluations and process. Those with economic interests, however, challenge IARC's cancer evaluations, most recently for glyphosate and red and processed meats, and are conducting a campaign including intervention from US Congressional Representatives to discredit IARC's review process and to undermine financial support—a campaign intimidating to IARC and Working Group members. Challenges to scientific interpretations serve to advance science and should be resolved by scientific experts who do not have conflicts of interest. Such interference does not bode well for the free flow of scientific information that informs and protects the public from risks of cancer.  相似文献   
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This study uses a sandblasted/acid-etched implant vs a smooth-surface implant to compare implant mobility and clinical reactions of peri-implant tissues to experimentally induced peri-implantitis in Beagle dogs. The right and left mandibular premolars were extracted from 5 Beagle dogs, and 2 smooth-surface (SS) implants and 2 sandblasted/acid-etched (SLA) implants were placed in each animal. After 120 days, healing abutments were connected. Fifteen days later, the prosthetic abutments were connected, the hygiene regimen was suspended, and peri-implantitis was induced by the insertion of cotton ligatures into the soft tissue around the implants. At baseline and 30, 60, and 90 days later, clinical attachment level (CAL), probing depth (PD), and mobility (MO) were measured. Probing depth increased significantly in the SLA group alone when baseline PD was compared with 30-, 60-, and 90-day evaluations (P < .05). No significant differences were noted between the 2 implant groups (P > .05). The loss in CAL was significant in both groups when the baseline value was compared with 30-, 60-, and 90-day evaluations (P < .02). Comparison between the 2 implant groups revealed a greater loss in CAL in the SLA group at the 90-day evaluation period (P = .04). A significant increase in mobility was seen in both groups when baseline values and 90-day evaluations were compared (P < .04). However, no statistically significant differences were noted between the 2 implant groups (P > .05). Experimentally induced peri-implantitis results in a greater loss of CAL in SLA implants than in SS implants in dogs; however, no differences in mobility or in PD have been noted between the 2 implant groups.  相似文献   
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OBJECTIVES: This study evaluated the effect of a warm or cold air-dry stream for solvent evaporation on the microtensile resin-dentin bond strength (muTBS), nanoleakage pattern (SEM), degree of conversion (DC) and solvent evaporation rates (SE) of an ethanol/water- (Adper Single Bond, [SB] 3MESPE) and an acetone-based (Prime & Bond 2.1, [PB] Dentsply), two-step etch-and-rinse adhesive system. MATERIALS AND METHODS: Adhesives were applied on demineralized dentin surfaces. For SE, a warm or cold air-dry stream (10 s) was applied prior to light-activation (10 s). Bonded sticks (0.8mm2) were tested in tension (0.5 mm/min). Two bonded sticks from each tooth were immersed in a 50% (w/v) solution of silver nitrate (24 h), photodeveloped (8 h) and analyzed by SEM. The DC and solvent evaporation rate of the adhesives were evaluated under FTIR and analytical balance, respectively. Data were analyzed by two-way ANOVA and Tukey test (alpha=0.05). RESULTS: Higher muTBS and lower nanoleakage were observed when the SE step was performed with warm air-dry stream. However, the DC of the adhesives was not altered by the use of a warm air-dry. CONCLUSIONS: The use of a warm air-dry stream seems to be a clinical tool to improve the bond strength and the quality of the hybrid layer (less nanoleakage infiltration), since it might reduce the number of pores within the adhesive layer.  相似文献   
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