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991.
VT Lehman RE Carter DO Claassen RC Murphy V Lowe RC Petersen PJ Peller 《Clinical nuclear medicine》2012,37(8):721-726
992.
993.
Martin MH Nielsen MB Petersen SM Jakobsen LM Rugulies R 《Journal of occupational rehabilitation》2012,22(3):427-436
Purpose Interventions to promote return to work (RTW) after sickness absence are often complex, involving numerous stakeholders and thus prone to implementation problems. To understand the outcomes of such interventions, researchers need to look beyond effectiveness data and incorporate systematic process evaluations. This article presents findings from a process evaluation of a coordinated and tailored RTW-intervention for employees with mental health problems. The purpose was to elucidate the implementation process and identify barriers for the feasibility and sustainability of the intervention. Methods The evaluation draws on comprehensive data from observations of and documents from the intervention, a two-waved survey among participants (n?=?76), two group interviews with the intervention team, three group interviews with municipal social insurance officers (SIOs), and ten individual interviews with participants. Results We identified several barriers to the feasibility and sustainability of the intervention: (1) the inclusion criteria were perceived as too narrow by those responsible for recruitment (SIOs); (2) waiting lists occurred; (3) participants had more severe mental health problems than expected; (4) key stakeholders had divergent expectations of the timeframe for RTW; (5) the SIOs felt insufficiently informed about the intervention; (6) the global financial downturn resulted in many participants losing their job, which impeded workplace-based RTW-efforts. Conclusions This study points out important pitfalls in implementing RTW-interventions, pertaining to specification of the target population, consideration of contextual constraints, and ensuring cooperation between key stakeholders. Thorough assessment of local context and stakeholder needs and concerns is likely to improve the feasibility and sustainability of future RTW-interventions. 相似文献
994.
995.
Vitamin D deficiency during pregnancy has been associated with the development of several adverse health outcomes, e.g., pre-eclampsia, gestational diabetes mellitus, preterm delivery, low birth weight, birth length, and bone mineral content. The aims of the present study were to estimate the intake and sources of vitamin D in Danish pregnant women and to examine potential determinants of vitamin D intake of the recommended level (10 μg per day). In 68,447 Danish pregnant women the mean ± SD for vitamin D intake was 9.23 ± 5.60 μg per day (diet: 3.56 ± 2.05 μg per day, supplements: 5.67 ± 5.20 μg per day). 67.6% of the women reported use of vitamin D supplements but only 36.9% reported use of vitamin D supplements of at least 10 μg. Supplements were the primary source of vitamin D for the two higher quartiles of total vitamin D intake, with diet being the primary source for the two lower quartiles. Determinants of sufficient total vitamin D intake were: high maternal age, nulliparity, non-smoking, and filling out of the Food Frequency Questionnaire (FFQ) during summer or fall. We propose that clinicians encourage vitamin D supplementation among pregnant women, with special focus on vulnerable groups such as the young, smokers and multiparous women, in order to improve maternal and fetal health both during and after pregnancy. 相似文献
996.
Schecter A Szabo DT Miller J Gent TL Malik-Bass N Petersen M Paepke O Colacino JA Hynan LS Harris TR Malla S Birnbaum LS 《Environmental health perspectives》2012,120(9):1260-1264
Background: Hexabromocyclododecane (HBCD) is a brominated flame retardant used in polystyrene foams in thermal insulation and electrical equipment. The HBCD commercial mixture consists mainly of α, β, and γ stereoisomers. Health concerns of HBCD exposure include alterations in immune and reproductive systems, neurotoxic effects, and endocrine disruption. Stereoisomer-specific levels of HBCD have not been measured previously in U.S. food.Objectives: We measured HBCD stereoisomer levels in U.S. foods from Dallas, Texas, supermarkets.Methods: Convenience samples of commonly consumed foods were purchased from supermarkets in Dallas in 2009-2010. Food samples included a wide variety of lipid-rich foods: fish, peanut butter, poultry, pork, and beef. Thirty-six individual food samples were collected in 2010 and analyzed for α-, β-, and γ-HBCD stereoisomers using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Ten pooled food samples previously collected in 2009 for a study of total HBCD levels using gas chromatography-mass spectrometry (GC-MS), were reanalyzed for α-, β-, and γ-HBCD stereoisomers using LC-MS/MS.Results: Of the 36 measured individual foods, 15 (42%) had detectable levels of HBCD. Median (ranges) of α- and γ-HBCD concentrations were 0.003 (< 0.005-1.307) and 0.005 (< 0.010-0.143) ng/g wet weight (ww), respectively; β-HBCD was present in three samples with a median (range) of 0.003 (< 0.005-0.019) ng/g ww. Median levels (range) for α-, β-, and γ-HBCD, in pooled samples were 0.077 (0.010-0.310), 0.008 (< 0.002-0.070), and 0.024 (0.012-0.170) ng/g ww, respectively.Conclusions: α-HBCD was detected most frequently and at highest concentrations, followed by γ-, and then β-HBCD, in food samples from Dallas, Texas. Food may be a substantial contributor to the elevated α-HBCD levels observed in humans. These data suggest that larger and more representative sampling should be conducted. 相似文献
997.
Methodological considerations for testing the ecotoxicity of carbon nanotubes and fullerenes: review
The recent emergence of manufactured nanoparticles (NPs) that are released into the environment and lead to exposure in organisms has accelerated the need to determine NP toxicity. Techniques for measuring the toxicity of NPs (nanotoxicology) in ecological receptors (nanoecotoxicology) are in their infancy, however, and establishing standardized ecotoxicity tests for NPs are presently limited by several factors. These factors include the extent of NP characterization necessary (or possible) before, during, and after toxicity tests such that toxic effects can be related to physicochemical characteristics of NPs; determining uptake and distribution of NPs within exposed organisms (does uptake occur or are effects exerted at organism surfaces?); and determining the appropriate types of controls to incorporate into ecotoxicity tests with NPs. In this review, the authors focus on the important elements of measuring the ecotoxicity of carbon NPs (CNPs) and make recommendations for ecotoxicology testing that should enable more rigorous interpretations of collected data and interlaboratory comparisons. This review is intended to serve as a next step toward developing standardized tests that can be incorporated into a regulatory framework for CNPs. 相似文献
998.
Waissi-Leinonen GC Petersen EJ Pakarinen K Akkanen J Leppänen MT Kukkonen JV 《Environmental toxicology and chemistry / SETAC》2012,31(9):2108-2116
An environmentally realistic method to test fullerene (C(60) ) toxicity to the benthic organism Chironomus riparius was created by allowing suspended fullerenes to settle down, making a layer on top of the sediment. To test the hypothesis that higher food concentrations will reduce toxic responses, two food concentrations were tested (0.5 and 0.8% Urtica sp.) in sediment containing fullerene masses of 0.36 to 0.55?mg/cm(2) using a 10-d chronic test. In the 0.5% food level treatments, there were significant differences in all growth-related endpoints compared with controls. Fewer effects were observed for the higher food treatment. Fullerene agglomerates were observed by electron microscopy in the gut, but no absorption into the gut epithelial cells was detected. In the organisms exposed to fullerenes, microvilli were damaged and were significantly shorter. The potential toxicity of fullerene to C. riparius appears to be caused by morphological changes, inhibiting larval growth. Environ. Toxicol. Chem. 2012; 31: 2108-2116. ? 2012 SETAC. 相似文献
999.
Matthias G Friedrich Chiara Bucciarelli-Ducci James A White Sven Plein James C Moon Ana G Almeida Christopher M Kramer Stefan Neubauer Dudley J Pennell Steffen E Petersen Raymond Y Kwong Victor A Ferrari Jeanette Schulz-Menger Hajime Sakuma Erik B Schelbert éric Larose Ingo Eitel Iacopo Carbone Andrew J Taylor Alistair Young Albert de Roos Eike Nagel 《Journal of cardiovascular magnetic resonance》2014,16(1)
1000.
Extracorporeal shock-wave lithotripsy and methyl tert-butyl ether for partially calcified gallstones 总被引:1,自引:0,他引:1
C J Peine B T Petersen H J Williams C E Bender D E Patterson J W Segura D M Nagorney M A Warner J L Thistle 《Gastroenterology》1989,97(5):1229-1235
To explore the possibility that gallbladder stone fragments might be able to be safely dissolved using methyl tert-butyl ether immediately after extracorporeal shock-wave lithotripsy (ESWL), a feasibility study in 8 patients with one to four partially calcified gallbladder stones was performed. The gallstones averaged 2.2 cm in diameter (range 1.3-3 cm) and contained layered or diffuse calcium detectable by computed tomography scan only (7 patients) or plain film (1 patient). After a 5F (1.7 mm) pigtail catheter was placed percutaneously into the gallbladder, ESWL fragmentation was performed using a renal stone lithotriptor. The patients were under general anesthesia and in the prone position on a support gantry designed for gallbladder stone ESWL. Following ESWL, methyl tert-butyl ether was infused and aspirated via the gallbladder catheter until no further stone material was radiologically detectable or could be dissolved. After 8-26 h (mean = 13 h) of methyl tert-butyl ether therapy, no radiologically detectable gallstones remained in 6 of 8 patients. Shell fragments of three peripherally calcified stones in 1 patient and the densely calcified, predominantly pigment stone in a second patient were refractory to combined therapy. Both ESWL and treatment with methyl tert-butyl ether were well tolerated in all patients, although bile leakage after catheter removal occurred in 3 patients, one of whom was treated by cholecystectomy. Additional measures to prevent bile leakage may be advisable if these two modalities are to be used in tandem. We found no evidence, however, that predissolution stone fragmentation with ESWL predisposed the gallbladder to either mucosal damage by methyl tert-butyl ether or increased absorption of it. 相似文献