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This study compared caries detection by multiple clinicians with the accuracy of detection with Caries Detector dye. Four clinicians rated the extent of caries on 100 extracted teeth. After dye application, visual assessment of residual dye was recorded for each specimen. This was repeated after the teeth were embedded in epoxy resin and sectioned. The results indicate that although reasonably accurate overall, clinicians often disagree whether caries is present. The use of a caries detector solution may be a valuable adjunct tool to correct caries diagnosis. 相似文献
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In outbred rats, increases in brain neuropeptide Y (NPY) activity suppress ethanol consumption in a variety of access conditions, but only following a history of ethanol dependence. NPY reliably suppresses ethanol drinking in alcohol-preferring rats, and this effect is augmented following a period of ethanol abstinence. The purpose of this experiment was to examine the effects of NPY on two-bottle choice ethanol drinking and feeding in Wistar rats that had undergone chronic ethanol vapor exposure, cycles of ethanol abstinence, or both. Ethanol-drinking Wistar rats were given 6 weeks of access to 15% (vol/vol) ethanol and water followed by either: two cycles of 1 week ethanol vapor exposure and 2 weeks with no ethanol; two cycles of 1 week ethanol bottle availability and 2 weeks with no ethanol; or 2 weeks of ethanol vapor exposure. Rats were infused intracerebroventricularly with one of four NPY doses (0.0, 2.5, 5.0, or 10.0 μg) following the ethanol exposure patterns described above, and tested for ethanol drinking and feeding in a two-bottle choice situation. NPY dose dependently increased food intake regardless of ethanol exposure history, but suppressed ethanol drinking only in rats that underwent cycles of ethanol access and ethanol abstinence. These results support the notion that dysregulation of brain NPY systems during chronic intermittent ethanol exposure is important in the motivational drive for subsequent relapse to ethanol drinking. 相似文献
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In this study, the authors' objective was to determine the influence of blood lead, meso 2,3-dimercaptosuccinic acid (DMSA)-chelatable lead, and tibial lead on systolic and diastolic blood pressures and on hypertension in 543 former organolead manufacturing workers. All workers had past exposure to inorganic and organic lead. The authors used linear regression to model systolic and diastolic blood pressure separately, and logistic regression was used for the modeling of hypertension status (i.e., systolic blood pressure > 160 mm Hg, diastolic blood pressure > or =96 mm Hg, or current use of antihypertensive medications). Blood lead, DMSA-chelatable lead, and tibial lead levels had means (standard deviations appear within parentheses) of 4.6 microg/dl (2.6 microg/dl), 19.3 microg (17.2 microg), and 14.4 microg/g (9.3 microg/g), respectively. The authors adjusted for covariates, and they found that blood lead was a predictor of (1) both systolic and diastolic blood pressures and (2) hypertension status in men < 58 y of age. DMSA-chelatable lead and tibial lead were not associated with any of the blood pressure measures. Systolic blood pressure was elevated by blood lead levels as low as 5 microg/dl. We speculate that lead may have a transient influence on blood pressure that is related to target dose levels obtained once release of lead from body stores has occurred. 相似文献
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Abstract: Pregnancy following rape is a continuing and significant public health issue. We estimate that the 333,000 sexual assaults and rapes reported in 1998, along with many more unreported, were responsible for 25,000 pregnancies. Potentially, as many as 22,000 such pregnancies could be prevented if all women who were raped received prompt medical services, and if not already protected against pregnancy, were provided with emergency contraceptive treatment. 相似文献