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PURPOSE OF REVIEW: The present review describes recent advances in our understanding about the epidemiology of human papillomavirus infection among female adolescents and describes several adolescent-specific issues related to administering human papillomavirus vaccines. RECENT FINDINGS: National estimates demonstrate that human papillomavirus infection is most prevalent among adolescents and young adults. Parents, patients, and providers have a high interest in vaccination against this virus, but current patterns of adolescent healthcare utilization suggest that changes in adolescent preventive care delivery may be needed to provide these vaccines in a timely manner. Debate over whether adolescents should be legally allowed to self-consent to vaccination is another issue that remains unresolved and could have a substantial impact on vaccination rates. Legislation on school entry requirements related to human papillomavirus vaccination has been introduced in many states as a mechanism to circumvent some of these concerns, but the details of this legislation and its effect on adolescent vaccine utilization remain to be determined. SUMMARY: Female adolescents are at a high risk for human papillomavirus infection and are likely to derive significant benefits from vaccination against this virus. However, administering human papillomavirus vaccines to this age group will require providers to be familiar with several issues unique to the adolescent population.  相似文献   
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Aim: Transarterial chemoembolisation (TACE) is recommended therapy for intermediate-stage hepatocellular carcinoma (HCC). However, the wide variations in outcom...  相似文献   
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Background

Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers.

Objectives

We examined changes of blood and urinary biomarkers following exposures to three particle sizes.

Methods

Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences.

Results

One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs.

Conclusions

Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.

Citation

Liu L, Urch B, Poon R, Szyszkowicz M, Speck M, Gold DR, Wheeler AJ, Scott JA, Brook JR, Thorne PS, Silverman FS. 2015. Effects of ambient coarse, fine, and ultrafine particles and their biological constituents on systemic biomarkers: a controlled human exposure study. Environ Health Perspect 123:534–540; http://dx.doi.org/10.1289/ehp.1408387  相似文献   
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