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991.
992.
Background: The prevalence of smokeless tobacco use in the United States Air Force (USAF) exceeds civilian use rates. The prevalence and correlates of smokeless tobacco use were assessed and evaluated in a sample of USAF trainees. Methods: We conducted a cross-sectional survey of USAF technical training school personnel at Joint Base San Antonio-Lackland and Fort Sam Houston (N = 14,810). Survey completion rate was 78%. Logistic regression was used to analyze the associations between demographic variables, tobacco use, and social factors for both regular and infrequent smokeless tobacco (e.g., chewing tobacco, snuff) users. Results: Overall, 16% of Airmen had ever used smokeless tobacco and 10% regularly used smokeless tobacco. In multivariate analyses, men had greater odds than women of regular smokeless tobacco use (adjusted odds ratio [OR] = 15.2; 95% confidence interval [CI]: 10.8–21.5) and infrequent smokeless tobacco use (adjusted OR = 4.2; 95% CI: 3.1–5.7). Smokeless tobacco use was associated with participation in high school sports (adjusted OR = 1.9; 95% CI: 1.6–2.3 for regular users; adjusted OR = 1.4; 95% CI: 1.1–1.7 for infrequent users), smoking cigarettes (adjusted OR = 4.3; 95% CI: 3.6–5.1 for regular users; adjusted OR = 4.0; 95% CI: 3.2–5.0 for infrequent users), or living with someone who used smokeless tobacco (adjusted OR = 2.2; 95% CI: 1.9–2.6 for regular users; adjusted OR = 1.4; 95% CI: 1.1–1.7 for infrequent users). Black or African Americans were less likely than whites to be regular (adjusted OR = 0.3; 95% CI: 0.1–0.4) or infrequent (adjusted OR = 0.3; 95% CI: 0.2–0.4) users of smokeless tobacco. Conclusions: Smokeless tobacco use among incoming Air Force recruits is common and negatively impacts the Air Force's goal to be tobacco-free. Understanding sociodemographic characteristics perpetuating smokeless tobacco use in the Air Force population can inform the development of health promotion interventions.  相似文献   
993.
BACKGROUND: Severe forms of periodontitis are suggested to have a genetic basis. OBJECTIVE: The aim of the present investigation was to study the association of gene polymorphisms related to some immune regulation components (G-308A TNFA, Q551R IL-4RA and C-159T CD14) with severe chronic periodontitis. MATERIALS AND METHODS: Sixty patients (aged 36-74 years; mean 54.5+/-8.5) with severe and generalized chronic periodontitis were included. The patients exhibited bone loss >50% at all teeth. Thirty-nine periodontally healthy subjects between 35 and 78 years of age (mean 51.0+/-10.9) were recruited as controls. DNA was isolated from peripheral blood cells and genotyping was performed by combination of PCR and restriction endonuclease mapping. RESULTS: While gene polymorphisms for TNFA and IL-4RA did not show any association with severe chronic periodontitis, the analysis of the -159 CD14 gene polymorphism revealed significant differences between test and control groups. The proportion of subjects that exhibited the TT genotype was significantly smaller in the group with severe periodontitis than in periodontal healthy group (p=0.028; Fisher's exact test). The C allele carriage was 90% in the periodontitis group and significantly higher than in the healthy control group (72%). CONCLUSION: It is suggested that the -159 CD14 gene polymorphism is associated with chronic periodontitis in Caucasian subjects of a north European origin.  相似文献   
994.
995.
Diltiazem hydrochloride is a commonly prescribed medication in the treatment of cardiovascular disease. A case of diltiazem-induced hyperpigmentation in a patient after significant sun exposure is reported. The morphological appearance was reticulated and slate-gray to blue in color. The pathogenesis of the hyperpigmentation is discussed and possible treatment options are reviewed.  相似文献   
996.
Multiple high-dose methamphetamine administrations cause long-lasting (>1 week) deficits in striatal dopaminergic neuronal function. This stimulant likewise causes rapid (within 1 h) and persistent (at least 48 h) decreases in activities of striatal: 1) dopamine transporters, as assessed in synaptosomes; and 2) vesicular monoamine transporter -2 (VMAT-2), as assessed in a non-membrane-associated (referred to herein as cytoplasmic) vesicular subcellular fraction. Importantly, not all brain areas are vulnerable to methamphetamine-induced long-lasting deficits. Similarly, the present study indicates that methamphetamine exerts differential acute effects on monoaminergic transporters according to brain region. In particular, results revealed that in the nucleus accumbens, methamphetamine rapidly, but reversibly (within 24 h), decreased plasmalemmal dopamine transporter function, without effect on plasmalemmal dopamine transporter immunoreactivity. Methamphetamine also rapidly and reversibly (within 48 h) decreased cytoplasmic VMAT-2 function in this region, with relatively little effect on cytoplasmic VMAT-2 immunoreactivity. In contrast, methamphetamine did not alter either dopamine transporter or VMAT-2 activity in the hypothalamus. Noteworthy, the nucleus accumbens and hypothalamus did not display the persistent long-lasting striatal dopamine depletions caused by the stimulant. Taken together, these data suggest that deficits in plasmalemmal and vesicular monoamine transporter activity lasting greater than 24-48 h may be linked to the long-lasting dopaminergic deficits caused by methamphetamine and appear to be region specific.  相似文献   
997.
Novel hybrid, composite polymer electrolytes (HCPEs) based on poly(acrylonitrile‐r‐butadiene) (PAN‐r‐PB), CN‐modified silica nanoparticles (CN‐MSNs), Li triflate, and ionic liquids (ILs) are synthesized. Using a combination of methods, it is demonstrated that these materials segregate into PAN‐rich and PB‐rich phases, the behavior of which changes depending on the IL type. The incorporation of ILs containing hexyl and octyl substituents at the imidazolium rings leads to a higher mobility of the PB‐rich phase and a decrease of the density of the neighboring PAN‐rich phase, allowing an improvement of the Li ion conductivity. However, with an increase of the substituent length from decyl to dodecyl, ordering of the hydrophobic tails in the PB‐rich phase leads to both stiffening of the latter and corresponding ordering of the ionic pairs of ILs, resulting in a decreased conductivity. The results of this work are broadly applicable for controlling the structure and properties of polymeric materials exhibiting microphase segregation.

  相似文献   

998.

Purpose

The aim is to study the influence of change in work–time control (WTC) on work–home interference (WHI) while adjusting for other work-related factors, demographics, changes at work and WHI at baseline among women and men. An additional aim was to explore sex differences in the relation between change in WTC and WHI.

Methods

The study included working participants of the Swedish Longitudinal Occupational Survey of Health (SLOSH) study of the third (2010) and fourth (2012) waves (n?=?5440). Based on a seven-item index, four groups of WTC were formed: stable high (40 %), stable low (42 %), increasing (9 %), or decreasing (9 %) WTC over the 2 years. WHI was measured by four items and individuals were categorised in whether suffering or not suffering of WHI. Sex-stratified logistic regression analyses with 95 % confidence intervals (CI) were used to estimate the odds of experiencing WHI by change in WTC.

Results

Controlling for demographics and work-related factors, women with stable low (OR?=?1.46; 95 % CI 1.14–1.88) and women and men with decreasing WTC (women OR?=?1.99; 95 % CI 1.38–2.85; men OR?=?1.80; 95 % CI 1.18–2.73) had higher odds of WHI than those with a stable high WTC. Additionally, adjusting for changes at work and WHI at baseline did not alter the results substantially. Interaction analysis did not reveal any significant sex difference in the relation between WTC and WHI.

Conclusions

For both women and men decreased and for women only, low control over working hours resulted in WHI also after adjusting for work-related factors and demographics.
  相似文献   
999.
The oxytocinase subfamily of M1 aminopeptidases plays an important role in processing and trimming of peptides for presentation on major histocompatibility (MHC) Class I molecules. Several large-scale genomic studies have identified association of members of this family of enzymes, most notably ERAP1 and ERAP2, with immune-mediated diseases including ankylosing spondylitis, psoriasis and birdshot chorioretinopathy. Much is now known about the genetics of these enzymes and how genetic variants alter their function, but how these variants contribute to disease remains largely unresolved. Here we discuss what is known about their structure and function and highlight some of the knowledge gaps that affect development of drugs targeting these enzymes.  相似文献   
1000.
Distraction osteogenesis is a gradual incremental bone-lengthening technique that requires very precise treatment planning and surgical execution. Subtle variation in the position of the corticotomy/osteotomy or in the position of the distraction device will affect the ultimate position of the tooth-bearing (distal) segment. Other functional and/or anatomic factors (that at this time are not well understood) also have an influence on the direction in which the tooth-bearing segment moves during distraction. These factors combine to create a discrepancy between the planned direction and the actual or observed direction of distraction. The charge for the orthodontist is to plan, as carefully as possible and in concert with the surgeon, the direction (vector) in which the tooth-bearing segment will travel during distraction. Further, the orthodontist must be able to modify the position that the tooth-bearing segment takes by exerting orthopedic and orthodontic forces and by making adjustments to the distraction device. In addition, the orthodontist must prepare the dentition before distraction, manage the dentition during distraction, and finish the occlusion after distraction in a manner that is different from more traditional jaw-respositioning techniques.  相似文献   
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