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31.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Gefahrstoffe sind in der Arbeitswelt allgegenwärtig. Beschäftigte aus allen Branchen sind bei ihrer Arbeit mit...  相似文献   
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Objectives

To investigate whether functional overreaching affects locomotor system behaviour when running at fixed relative intensities and if any effects were associated with changes in running performance.

Design

Prospective intervention study.

Methods

Ten trained male runners completed three training blocks in a fixed order. Training consisted of one week of light training (baseline), two weeks of heavy training designed to induce functional overreaching, and ten days of light taper training designed to allow athletes to recover from, and adapt to, the heavy training. Locomotor behaviour, 5-km time trial performance, and subjective reports of training status (Daily Analysis of Life Demands for Athletes (DALDA) questionnaire) were assessed at the completion of each training block. Locomotor behaviour was assessed using detrended fluctuation analysis of stride intervals during running at speeds corresponding to 65% and 85% of maximum heart rate (HRmax) at baseline.

Results

Time trial performance (effect size ±95% confidence interval (ES): 0.16 ± 0.06; p < 0.001), locomotor behaviour at 65% HRmax (ES: ?1.12 ± 0.95; p = 0.026), and DALDA (ES: 2.55 ± 0.80; p < 0.001) were all detrimentally affected by the heavy training. Time trial performance improved relative to baseline after the taper (ES: ?0.16 ± 0.10; p = 0.003) but locomotor behaviour at 65% HRmax (ES: ?1.18 ± 1.17; p = 0.048) and DALDA (ES: 0.92 ± 0.90; p = 0.045) remained impaired.

Conclusions

Locomotor behaviour during running at 65% HRmax was impaired by functional overreaching and remained impaired after a 10-day taper, despite improved running performance. Locomotor changes may increase injury risk and should be considered within athlete monitoring programs independently of performance changes.  相似文献   
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Objective

To examine the experience of interracial anxiety among health professionals and how it may affect the quality of their interactions with patients from racially marginalized populations. We explored the influence of prior interracial exposure—specifically through childhood neighborhoods, college student bodies, and friend groups—on interracial anxiety among medical students and residents. We also examined whether levels of interracial anxiety change from medical school through residency.

Data Source

Web-based longitudinal survey data from the Medical Student Cognitive Habits and Growth Evaluation Study.

Study Design

We used a retrospective longitudinal design with four observations for each trainee. The study population consisted of non-Black US medical trainees surveyed in their 1st and 4th years of medical school and 2nd and 3rd years of residency. Mixed effects longitudinal models were used to assess predictors of interracial anxiety and assess changes in interracial anxiety scores over time.

Principal Findings

In total, 3155 non-Black medical trainees were followed for 7 years. Seventy-eight percent grew up in predominantly White neighborhoods. Living in predominantly White neighborhoods and having less racially diverse friends were associated with higher levels of interracial anxiety among medical trainees. Trainees' interracial anxiety scores did not substantially change over time; interracial anxiety was highest in the 1st year of medical school, lowest in the 4th year, and increased slightly during residency.

Conclusions

Neighborhood and friend group composition had independent effects on interracial anxiety, indicating that premedical racial socialization may affect medical trainees' preparedness to interact effectively with diverse patient populations. Additionally, the lack of substantial change in interracial anxiety throughout medical training suggests the importance of providing curricular tools and structure (e.g., instituting interracial cooperative learning activities) to foster the development of healthy interracial relationships.  相似文献   
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Background

Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.

Methods

A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.

Results

Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.

Conclusion

Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile.  相似文献   
37.

Objective

To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.

Design

Observational nationwide cohort study.

Setting

Linked population data from the Australian Childhood Immunisation Register and National Death Index.

Participants

Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.

Main outcome measures

Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.

Results

The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.

Conclusion

Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality.  相似文献   
38.
Parabens are antimicrobial additives found in a wide array of consumer products. However, the halogenated compounds formed from parabens during wastewater disinfection are a potential environmental concern. In order to identify these transformation products and investigate their mechanism of formation, a synthetic route to ethyl parabens labeled with the stable isotope carbon-13 at specific positions within the benzene ring was developed. This efficient two-step procedure starts from commercially available 13C-labeled phenols and involves (1) initial acylation of the phenol via a Houben–Hoesch reaction with trichloroacetonitrile followed by (2) a modified haloform reaction of the resulting trichloromethyl ketone to afford the corresponding 13C-labeled ethyl parabens in 65%–80% overall yield. The scope of the modified haloform reaction was also investigated, allowing for the synthesis of other parabens derived from primary or secondary alcohols, including 13C- and deuterium-labeled esters. In addition, 4-hydroxybenzoic acid can be formed directly from the common trichloromethyl ketone intermediate upon treatment with lithium hydroxide. This protocol complements existing methods for preparing 13C-labeled paraben derivatives and offers the specific advantages of exhibiting complete regioselectivity in the Houben–Hoesch reaction (to form the para-disubstituted product) and avoiding the need for protecting groups in the modified haloform reaction that forms the paraben esters.  相似文献   
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