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1.
Lauren Porter Jennifer Duke Meredith Hennon David Dekevich Erik Crankshaw Ghada Homsi Matthew Farrelly 《PloS one》2015,10(5)
Recent youth trends in the prevalence of e-cigarette and traditional cigarette use in Florida were examined in a cross-sectional, representative state sample from 2011 to 2014. Traditional cigarette use among youth declined during the study period. Experimentation with and past 30-day use of e-cigarettes among Florida youth tripled over 4 years. Past 30-day e-cigarette use exceeded traditional cigarette use in 2014; 10.8% of high school and 4.0% of middle school students reported recent e-cigarette use, compared with 8.7% of high school and 2.9% of middle school students for traditional cigarettes (P<0.001). By 2014, 20.5% of high school and 8.5% of middle school students reported ever use of e-cigarettes. Among ever e-cigarette users in 2014, 30.3% of high school and 42.2% of middle school students had never smoked traditional cigarettes. Given the concern that significant rates of e-cigarette use by U.S. adolescents may have a negative effect on public health, further review of e-cigarette advertising, marketing, sales, and use among U.S. youth is warranted. 相似文献
2.
The past few years have seen significant advances in our understanding of eukaryotic genomes. In the field of parasitology, this is best exemplified by the application of genome mapping techniques to the study of genome structure and function in the protozoan parasite, Leishmania. Although much is known about the organism and the diseases it causes, molecular genetics has only recently begun to play a major part in elucidating some of the unusual characteristics of this interesting parasite. Mapping of the small (35 Mb) genome and determination of the functional role of genes by the application of in vitro homologous gene targeting techniques are revealing novel avenues for the development of prophylactic measures. 相似文献
3.
H V Meredith 《American journal of physical anthropology》1979,51(1):63-66
This article examines a recently reported generalization. Materials from more than a score of invetigations are drawn upon. These materials show there is not a substantial research base for the claim that interbreeding in the United States between black people of African ancestry and white people of European ancestry has resulted in increased lower limb height relative to sitting height. 相似文献
4.
Meredith Root-Bernstein 《Behavioural processes》2010,84(2):608-616
Although the opportunity for errors in social learning is widely recognised, as yet little research has been directed towards understanding specific inaccuracies, biases and limitations in social learning and the mechanisms that give rise to them. In two experiments I ask how starlings, Sternus vulgaris, identify exemplars of novel feeders previously learned about socially. I find that starlings have a stronger response to feeders in the same context as that in which social learning took place, compared to identical and nonidentical feeders in a different context. Within a context that matches where social learning took place, starlings prefer feeders that show the same location and colour as the feeder demonstrated by the demonstrator starling, and show no preference when colour and location cues are dissociated. This suggests that starlings are relatively accurate social learners, since they show strong responses to novel foraging options only if they match the context, colour and location of options learned about socially, and they do so after very few trials. Furthermore, the responses of the subjects were compatible with conditioned learning-like mechanisms, which provide a useful basis for the further investigation of the origins and implications of errors in social learning. 相似文献
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Inhibition of Helicobacter pylori haemagglutination activity by human salivary mucins 总被引:1,自引:0,他引:1
A Mentis L Tzouvelekis C Spiliadis C C Blackwell D M Weir 《FEMS microbiology immunology》1990,2(3):125-127
Thirty isolates of Helicobacter pylori from gastric biopsies agglutinated human erythrocyte suspensions. Crude mucin preparations derived from saliva of 20 different donors were examined for their ability to inhibit haemagglutination. All mucin preparations exhibited strong inhibitory activity. Removal of sialic residues from mucin preparations by treatment with neuraminidase resulted in a substantial reduction of their inhibitory activity. The mucin preparations had no bactericidal or aggregation activity for H. pylori. These results are discussed in the context of the role of mucins in colonization of the gastric mucosa by H. pylori. 相似文献
8.
C. Meredith P. Symonds L. Webster D. Lamont E. Pyper C. R. Gillis L. Fallowfield 《BMJ (Clinical research ed.)》1996,313(7059):724-726
OBJECTIVE: To assess the needs of patients with cancer for information about their condition. DESIGN: Cross sectional survey of patients'' views by means of semistructured interview with questionnaire. SETTING: A regional cancer centre and two university hospitals in west Scotland. SUBJECTS: 250 (93%) of 269 cancer patients invited to participate in study who were selected by age, sex, socioeconomic status, and tumour site to be representative of cancer patients in west Scotland. MAIN OUTCOME MEASURES: Patients'' need to know whether they had cancer, the medical name of their illness, progress through treatment, how treatment works, side effects, chances of cure, and treatment options. RESULTS: 79% (95% confidence interval 73% to 84%) of patients wanted as much information as possible, and 96% (93% to 98%) had a need or an absolute need to know if they had cancer. Most patients also wanted to know the chance of cure (91% (87% to 94%)) and about side effects of treatment (94% (90% to 97%)). When the replies were cross tabulated with patients'' age, sex, deprivation score, and type of treatment there was a linear trend for patients from more affluent areas to want more information and those from deprived areas to want less. There was a strong preference for diagnosis of cancer to be given by a hospital doctor (60% (53% to 66%). CONCLUSION: Almost all patients wanted to know their diagnosis, and most wanted to know about prognosis, treatment options, and side effects. 相似文献
9.
Brooke E. Crowley Sandra Thorén Emilienne Rasoazanabary Erin R. Vogel Meredith A. Barrett Sarah Zohdy Marina B. Blanco Keriann C. McGoogan Summer J. Arrigo‐Nelson Mitchell T. Irwin Patricia C. Wright Ute Radespiel Laurie R. Godfrey Paul L. Koch Nathaniel J. Dominy 《Journal of Biogeography》2011,38(11):2106-2121
Aim We sought to quantify geographical variation in the stable isotope values of mouse lemurs (Microcebus) and to determine whether this variation reflects trophic differences among populations or baseline isotopic differences among habitats. If the latter pattern is demonstrated, then Microcebus can become a proxy for tracking baseline habitat isotopic variability. Establishing such a baseline is crucial for identifying niche partitioning in modern and ancient communities. Location We studied five species of Microcebus from eight distinct habitats across Madagascar. Methods We compared isotopic variation in C3 plants and Microcebus fur within and among localities. We predicted that carbon and nitrogen isotope values of Microcebus should: (1) vary as a function of abiotic variables such as rainfall and temperature, and (2) covary with isotopic values in plants. We checked for trophic differences among Microcebus populations by comparing the average difference between mouse lemur and plant isotope values for each locality. We then used multiple regression models to explain spatial isotope variation in mouse lemurs, testing a suite of explanatory abiotic variables. Results We found substantial isotopic variation geographically. Ranges for mean isotope values were similar for both Microcebus and plants across localities (carbon 3.5–4.0‰; nitrogen 10.5–11.0‰). Mean mouse lemur and plant isotope values were lowest in cool, moist localities and highest in hot, dry localities. Rainfall explained 58% of the variation in Microcebus carbon isotope values, and mean plant nitrogen isotope values explained 99.7% of the variation in Microcebus nitrogen isotope values. Average differences between mouse lemur and plant isotope values (carbon 5.0‰; nitrogen 5.9‰) were similar across localities. Main conclusions Isotopic data suggest that trophic differences among Microcebus populations were small. Carbon isotope values in mouse lemurs were negatively correlated with rainfall. Nitrogen isotope values in Microcebus and plants covaried. Such findings suggest that nitrogen isotope values for Microcebus are a particularly good proxy for tracking baseline isotopic differences among habitats. Our results will facilitate future comparative research on modern mouse lemur communities, and ecological interpretations of extinct Holocene communities. 相似文献
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