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101.
Daniel G. Busby Louise M. White Peter A. Pearce 《Archives of environmental contamination and toxicology》1991,20(1):25-31
Brain acetylcholinesterase (AChE) activity was measured in forest songbirds exposed to Ultra Ultra Low Volume (UULV) aerial spraying of fenitrothion in New Brunswick for spruce budworm control. Brain AChE activity was determined in 324 songbirds from the sprayed blocks and 47 from an unsprayed control area, and represented four species. In most cases, more than half of the individuals of any species sampled were diagnosed as exposed (20% inhibition) to the fenitrothion sprays and had a mean percent level of inhibition of 40% or greater, relative to mean control values. The proportion of birds with life-threatening levels of inhibition (50%) was usually less than 20%. The largest proportion of birds with life-threatening inhibition was found after the first 210 g AI/ha spray. The White-throated Sparrow had the highest proportion (25–55%) of individuals with life-threatening inhibition after all sprays. Brain AChE inhibition was greater in exposed birds collected after the first 210 g AI/ha spray than after the second one. Variation among species' responses to the sprays is discussed in relation to habitat and foraging preferences. Several sampling biases which may contribute to underestimation of the impact of fenitrothion spraying on birds are identified. 相似文献
102.
Stage migration in breast cancer: surgical decisions concerning isolated tumour cells and micro-metastases in the sentinel lymph node. 总被引:3,自引:0,他引:3
Louise de Widt-Levert Vivianne Tjan-Heijnen Peter Bult Theo Ruers Theo Wobbes 《European journal of surgical oncology》2003,29(3):216-220
AIMS: Sentinel lymph node biopsy has replaced the axillary lymph node dissection (ALND) in primary surgery for breast cancer in many hospitals and is expected to become the standard of care in due time. Since the sentinel lymph node is subjected to more extensive pathologic examination than the lymph nodes in the axillary dissection specimen, more patients are found to be node positive (N+); however many of them contain micro-metastases (相似文献
103.
Ringwalt Christopher L. Vincus Amy Ennett Susan Johnson Ruby Rohrbach Louise Ann 《Prevention science》2004,5(1):61-67
In this study we investigate reasons why teachers adapt substance use prevention curricula in the nation's middle schools. We hypothesize that these reasons will be most salient in schools with racially and ethnically diverse student populations, for whom teachers may believe it appropriate to tailor their curricula. The study sample comprised a nationally representative sample of lead substance use prevention teachers in the nation's middle schools. Respondents answered questions concerning eight student problems or needs that constituted reasons why they might adapt their prevention lessons. Controlling for a variety of school and teacher characteristics, we found that teachers in high minority schools were more likely to adapt curricula in response to three of the eight characteristics presented: youth violence, limited English proficiency, and various racial/ethnic or cultural groups. We suggest that curriculum developers make a systematic effort to understand how teachers are adapting their curricula in high minority schools and incorporate these modifications, if found effective, into their curricula. 相似文献
104.
105.
Michael G Sawyer Lauren Miller-Lewis Sophie Guy Melissa Wake Louise Canterford John B Carlin 《Ambulatory Pediatrics》2006,6(6):306-311
OBJECTIVE: To investigate the relationship between overweight and obesity, and mental health problems in Australian 4- to 5-year-old children. METHODS: The study used data from wave 1 (2004) of the Longitudinal Study of Australian Children (LSAC). The participants were 4983 4- to 5-year-old children (2537 boys and 2446 girls) with a mean age of 56.9 months (standard deviation 2.6 months; range 51-67 months). Children were classified as nonoverweight, overweight, and obese on the basis of International Obesity Task Force definitions. Mental health problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) completed by parents and teachers. RESULTS: Although obese 4- to 5-year-old boys had more mental health problems than nonoverweight boys, differences between the groups were small and substantially reduced when analyses controlled for children's sociodemographic characteristics. Parents reported that overweight/obese girls had more peer problems, whereas teachers reported they had more conduct problems. Children in all weight groups had mean scores within the normal range of scores on all the SDQ subscales. CONCLUSIONS: Differences in rates of mental health problems experienced by young children of different weight status appear relatively small. Higher rates of mental health problems experienced by more obese boys may reflect differences in their sociodemographic characteristics rather than their weight status per se. Policies that reduce the number of young children living in poverty or experiencing other adverse social circumstances have the potential to reduce rates of mental health problems experienced by older children with overweight/obesity. 相似文献
106.
107.
Louise Burke Douglas B Flieder Donald G Guinee Elizabeth Brambilla Andrew N Freedman William P Bennett Raymond T Jones Andrew Borkowski Neil A Caporaso Marian Fleming Victor Trastek Peter Pairolero Henry Tazelaar David Midthun James R Jett Lance A Liotta William D Travis Curtis C Harris 《Clinical cancer research》2005,11(1):232-241
PURPOSE: Many studies have highlighted the aberrant expression and prognostic significance of individual proteins in either the Rb (particularly cyclin D1, p16INK4A, and pRb) or the p53 (p53 and p21Waf1) pathways in non-small cell lung cancer. We hypothesize that cumulative abnormalities within each and between these pathways would have significant prognostic potential regarding survival. EXPERIMENTAL DESIGN: Our study population consisted of 106 consecutive surgically resected cases of predominantly early-stage non-small cell lung cancer from the National Cancer Institute-Mayo Clinic series, and assessment of proteins involved both immunohistochemical (cyclin D1, p21Waf1, pRb, p16INK4A, and p53) and mutational analysis (p53) in relationship to staging and survival. RESULTS: Cyclin D1 overexpression was noted in 48% of the tumors, p16INK4A negative in 53%, pRb negative in 17%, p53 immunopositive in 50%, p53 mutation frequency in 48%, and p21(Waf1) overexpression in 47%, none with prognostic significance. Cyclin D1 overexpression in pRb-negative tumors revealed a significantly worse prognosis with a mean survival of 2.3 years (P = 0.004). A simultaneous p53 mutation dramatically reduced the mean survival time to 0.9 years (P = 0.007). Cyclin D1 overexpression with either a p53 mutation or a p53 overexpression was also associated with a significantly poorer prognosis (P = 0.0033 and 0.0063, respectively). CONCLUSIONS: Some cumulative abnormalities in the Rb and p53 pathways (e.g., cyclin D1 overexpression and p53 mutations) significantly cooperate to predict a poor prognosis; however, the complexity of the cell cycle protein interaction in any given tumor warrants caution in interpreting survival results when specific protein abnormalities are taken in isolation. 相似文献
108.
Linda Enroth Domantas Jasilionis Laszlo Nmeth Bjrn Heine Strand Insani Tanjung Louise Sundberg Stefan Fors Marja Jylh Henrik Brnnum-Hansen 《European journal of ageing》2022,19(2):161
Overall progress in life expectancy (LE) depends increasingly on survival in older ages. The birth cohorts now reaching old age have experienced considerable educational expansion, which is a driving force for the social change and social inequality. Thus, this study examines changes in old age LE by educational attainment in the Nordic countries and aims to find out to what extent the change in national LEs is attributable to education-specific mortality and the shifting educational composition. We used national register data comprising total 65 + populations in Denmark, Finland, Norway and Sweden to create period life tables stratified by five-year age groups (65–90 +), sex and educational attainment. Difference in LE between 2001 and 2015 was decomposed into the contributions of mortality changes within each educational group and changes in educational composition. Increasing LE at all ages and in all educational groups coincided with persistent and growing educational inequalities in all countries. Most of the gains in LE at age 65 could be attributed to decreased mortality (63–90%), especially among those with low education, the largest educational group in most countries. The proportion of the increase in LE attributable to improved education was 10–37%, with the highest contributions recorded for women in Norway and Sweden. The rising educational levels in the Nordic countries still carry potential for further gains in national LEs. However, the educational expansion has contributed to uneven gains in LE between education groups, which poses a risk for the future increase of inequalities in LE.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-022-00698-y. 相似文献
109.
Louise Craddock Huw Cooper Alison Riley Tracy Wright 《Cochlear implants international》2016,17(2):26-30
Introduction: Increasing numbers of pre-lingually profoundly deaf adults are seeking a cochlear implant (CI). Pre- and post-operative outcomes are presented on 20 of these patients.Results: An Adult Pre-Lingually Profoundly Deaf Implant Profile (APDIP) weighted the pre-operative level of concern about potential CI benefit. Results indicated no group mean post-operative open-set improvement. However CUNY sentence testing (auditory plus lip-reading cues) revealed improved performance with a CI. Twelve out of 20 patients used their CIs for more than 10 hours per day, suggesting good usage. Moreover, hours of usage were positively associated with measured benefit on CUNY sentences in the lip-reading plus sound via CI condition. There was no apparent relationship between pre-operative level of concern and post-operative CI performance or hours of processor use.Conclusion: Results suggest implantation is beneficial and effective in this group. 相似文献
110.