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排序方式: 共有393条查询结果,搜索用时 31 毫秒
241.
242.
Diane Van Opstal Karin E.M. Diderich Marieke Joosten Lutgarde C.P. Govaerts Joke Polak Marjan Boter Jasper J. Saris Wai Yee Cheung Stefanie van Veen Robert van de Helm Attie T.J.I. Go Maarten F.C.M. Knapen Dimitri N.M. Papatsonis Anneke Dijkman Femke de Vries Robert-Jan H. Galjaard Lies H. Hoefsloot Malgorzata I. Srebniak 《黑龙江环境通报》2018,38(12):911-919
243.
Eleanor Harding Jennifer Hammond Lyn S. Chitty Melissa Hill Celine Lewis 《黑龙江环境通报》2020,40(8):1028-1039
Background
Tests in pregnancy such as chromosomal microarray analysis and exome sequencing are increasing diagnostic yield for fetal structural anomalies, but have greater potential to result in uncertain findings. This systematic review investigated the experiences of prospective parents about receiving uncertain results from these tests.Methods
A systematic search of three electronic databases was conducted. Data extraction was performed for studies that met the eligibility and quality criteria. Results were synthesised following the principles of thematic analysis.Results
Fourteen studies (10 qualitative, 4 quantitative) were included. Findings were grouped into three overarching themes. Sources of uncertainty included the testing procedure, the diagnosis and prognosis, and health professionals' own uncertainty. The clinical impact of the uncertainty included parents struggling to make clinical decisions with the information available, the emotional impact included decisional-regret, shock, worry and feeling overwhelmed. To manage the uncertainty, parents sought support from healthcare professionals, friends, family, the internet and other parents as well as remaining hopeful.Conclusions
Prospective parents experience a myriad of uncertainties in the prenatal setting, which must be handled sensitively. Future research should explore optimal ways of managing uncertainty to minimise harm. Recommendations are made for discussing uncertainty during pre- and post-test counseling. 相似文献244.
The field of prenatal screening and diagnosis for fetal anomalies has been marked by a rapid succession of technological advances, including most notably, chromosomal microarray analysis, and next generation sequencing. Despite the diagnostic advantages of these technologies, their incorporation into prenatal testing has created additional challenges of revealing genomic variants of unknown or uncertain significance, and secondary findings. While detailed posttest counseling about uncertain variants is best performed by medical geneticists, many of the screening and diagnostic tests that lead to this information are actually ordered by general maternity health care professionals (HCPs), such as obstetricians, midwives, and family physicians. Maternity HCPs support pregnant women through to the conclusion of their pregnancy and the postpartum period, and thus are close observers of the psychosocial impart of fetal genomic uncertainty on women and their families. While there have been many studies exploring the handling of genomic uncertainty by genetics HCPs, there has been relatively less attention paid to maternity HCPs without speciality training in genetics. This review explores the current literature surrounding nongenetic maternity HCPs' views and experiences of genomic uncertainty and returning uncertain results in the prenatal setting. 相似文献
245.
Bennie W. Good G. Vilcins W.R. Harvey D.A. Clabo Jr. A.L. Lewis 《Environment international》1982,8(1-6)
Two studies evaluating the levels and sources of nitrogen dioxide in approximately 90 employee homes in the Richmond area with continuous sampling during the weeks of August 5, 1980, and February 9, 1981, were performed using samplers in the living room, bedroom, kitchen, and outdoors. Additional data were collected concerning appliance usage, heating/cooling plant, ventilation and cigarette smoking. Results were analyzed using BMDP routines. The largest contributor to NO2 concentration was found to be gas-fired kitchen appliances. The mean kitchen level for homes with gas appliances during the winter study was 188 μg/m3. Excluding participants with gas kitchens, incremental influence due to cigarette smoking was detected. The 7-day, 3-room average level of NO2 in the homes of nonsmokers and smokers without gas-fired appliances was 12 and 15 μg/m3, respectively, in the summer. The corresponding winter values were 19 and 22 μg/m3. Furthermore, the individual levels of NO2 in the homes of smokers were generally below both the adjacent outdoor level and the National Ambient Air Quality Standard limit for annual exposure. 相似文献
246.
In interior western North America, many riparian forests dominated by cottonwood and willow are failing to reproduce downstream
of dams. We tested the hypothesis that establishment is now prevented by absence of the bare, moist substrate formerly provided
by floods and channel movement. Along Boulder Creek, a dammed stream in the Colorado plains, we tested the effects of disturbance
(sod removal), irrigation, and addition of seed on the establishment of seedings of plains cottonwood (Populus deltoides subsp.monilifera) and peachleaf willow (Salix amygdaloides). In unirrigated, undisturbed plots, mean cottonwood density was 0.03 seedlings/m2. Irrigation or disturbance alone produced mean cottonwood densities of 0.39 and 0.75 seedlings/m2. Plots that were both irrigated and disturbed produced a mean cottonwood density of 10.3 seedlings/m2. The effects of irrigation and disturbance on cottonwood establishment were significant (P<0.005); added seed had no significant effect (P=0.78). The few cottonwood seedlings in unirrigated plots were in low positions susceptible to scour by future moderate flows.
We conclude that cottonwood establishment along Boulder Creek is limited by the scarcity of bare, moist sites safe from future
scour. Establishment of peachleaf willow was significantly affected only by disturbance; daily sprinkler irrigation did not
provide sufficient moisture to increase survival of this species. Our results demonstrate the feasibility of restoring plains
cottonwood forests using natural seedfall, even where only widely scattered adult trees are present. Because use of natural
seedfall conserves the genetic makeup of the local population, this method may be preferable to the use of imported cuttings. 相似文献
247.
Scott E. Atkinson Donald H. Lewis 《Journal of Environmental Economics and Management》1976,3(4):363-380
This paper utilizes two least-cost emission control strategies and develops rules for structuring and implementing optimal air quality standards. A strategy typical of those currently enforced, based on the State Implementation Plans (SIP's ), is compared to two least-cost strategies: (i) ambient least cost (ALC ), which achieves required air quality at least cost; and (ii) emissions least cost (ELC ), which achieves required emissions reduction at least cost. A demonstration is given of the theoretically derived result that the ALC strategy should be utilized in cost-benefit analyses to determine air quality standards and to generate emissions taxes. Preliminary analysis of the St. Louis area indicated tentative justification for a particulate ambient standard at least as strict as the current Federal primary standard. The efficiency, equity, and administrative costs for implementation of strategies based on the least-cost concept are also examined. 相似文献
248.
Lewis Potter Spencer Duckworth 《Journal of the Air & Waste Management Association (1995)》2013,63(5):207-209
The practical necessity for continuous air monitoring by an instrument network is explained. Network criteria are listed. A coulometric monitoring system for oxidantis described and evaluated. Operating methods, calibration techniques, costs, and comparative field data are given. The authors conclude the coulometric system is feasible for operation on a widespread basis. Attractive features include: portability; remote recording; easy installation; centralized, coincident calibration of several monitors; linear data output; data consistent with other systems; and a potential for mobile use in horizontal and vertical surveys of the atmosphere. 相似文献
249.
OBJECTIVES: Most states now have lengthy learner periods for young, beginning drivers as part of their graduated driver licensing (GDL) systems. Although parents play a vital role during the learner stage of GDL by supervising driving practice, virtually nothing is known about the nature and quality of parental supervision. The objectives of this study were to investigate parents' supervisory behavior and parent-teen relationships during the learner stage of graduated licensing and to evaluate two approaches for assisting parents in supervising their teenager's early driving experience. METHODS: Families of teenagers applying for a learner permit received either a booklet describing highly structured practice sessions for beginning drivers, a series of "tip sheets" offering more generalized guidance, or no special materials. Questionnaires were sent separately to parents and teenagers three to six months after teenagers obtained their permit. RESULTS: Of 1,190 participating families, 653 parents (55%) and 609 teenagers (51%) responded. Both parents and teenagers perceived parents as supportive and helpful during driving sessions. Parents often demonstrated positive behaviors, such as complimenting their teenager and pointing out possible hazards; they also exhibited less desirable behaviors, such as raising their voice, but these were less frequent. A majority of parents (71%) and teenagers (52%) reported that they enjoyed spending this time together. About four months after obtaining a permit, most parents believed their teenager did not yet have enough experience and was not ready to drive unsupervised. Although the reported behaviors are encouraging, within-family agreement was low on most items. Finally, efforts to assist parents proved unsuccessful. Although parents thought the booklet and tip sheets were helpful, most used these materials only in a general way. CONCLUSIONS: The extended learning experience required by GDL programs is a positive experience for many families. However, finding a method for helping parents achieve maximum benefits during this process will be challenging. The results also suggest that current requirements in the learner phase of most state GDL systems (six months; 30-50 hours) may be inadequate to ensure that teenagers obtain a sufficient amount of experience to begin driving safely on their own. 相似文献
250.
Rushmila Haque Natalie Clapoudis Melissa King Ioni Lewis Melissa K. Hyde Patricia Obst 《Safety Science》2012,50(3):378-384
Annually, in Australia, 10-15% of all road-related fatalities involve pedestrians. Of those pedestrians fatally injured, approximately 45% were walking while intoxicated or ‘drink walking’. Drink walking is increasing in prevalence and younger persons may be especially prone to engage in this behaviour and, thus, are at heightened risk of being injured or killed. Presently, limited research is available regarding the factors which influence individuals to drink walk. This study explored young people’s (17-25 years) intentions to drink walk, using an extended Theory of Planned Behaviour (TPB). Participants (N = 215), completed a self-report questionnaire which assessed the standard TPB constructs (attitude, subjective norm, perceived behavioural control) as well as the extended constructs of risk perception, anticipated regret, and past behaviour. It was hypothesised that the standard TPB constructs would significantly predict individuals’ reported intentions to drink walk and that the additional constructs would predict intentions over and above the TPB constructs. The TPB variables significantly predicted 63.2% of the variance in individuals’ reported intentions to drink walk, and the additional variables, combined, explained a further 6.1% of the variance. Of the additional constructs, anticipated regret and past behaviour, but not risk perception, were significant predictors of drink walking intentions. As one of the first studies to provide a theoretically-based investigation of factors influencing individuals’ drink walking intentions, the current study’s findings have potentially significant implications for understanding young people’s decisions to drink walk and the design of future countermeasures to ultimately reduce this behaviour. 相似文献