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1.
Mahler SV  de Wit H 《PloS one》2010,5(11):e15475

Background

Pavlovian conditioning plays a critical role in both drug addiction and binge eating. Recent animal research suggests that certain individuals are highly sensitive to conditioned cues, whether they signal food or drugs. Are certain humans also more reactive to both food and drug cues?

Methods

We examined cue-induced craving for both cigarettes and food, in the same individuals (n = 15 adult smokers). Subjects viewed smoking-related or food-related images after abstaining from either smoking or eating.

Results

Certain individuals reported strong cue-induced craving after both smoking and food cues. That is, subjects who reported strong cue-induced craving for cigarettes also rated stronger cue-induced food craving.

Conclusions

In humans, like in nonhumans, there may be a “cue-reactive” phenotype, consisting of individuals who are highly sensitive to conditioned stimuli. This finding extends recent reports from nonhuman studies. Further understanding this subgroup of smokers may allow clinicians to individually tailor therapies for smoking cessation.  相似文献   

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OBJECTIVE: To compare data on the practices of molecular genetic testing (MGT) in laboratories in the United States with those in 18 other countries. METHODS: A Web-based survey of MGT laboratory directors (n = 827; response rate 63%) in 18 countries on three continents was carried out, and the response from U.S. laboratories compared to all others. Quality assurance and reporting indices were developed and calculated for each responding laboratory. RESULTS: A comparison of U.S. results with all other countries identified differences in laboratory setting, personnel qualifications, and the specific tests being offered, but similar rates of adherence to MGT quality standards and reporting practices were found. The survey also documented substantial transborder flow of specimens, most commonly due to the lack of availability of the test in the United States or because the test was available only through a research protocol, highlighting the need for common reporting and practice guidelines for the international MGT community. CONCLUSION: The findings presented here provide further support for the need to consider the application of the Organisation for Economic Cooperation and Development (OECD) Guidelines and the establishment of compatible accreditation programs or equivalent mechanisms across national borders to ensure the quality of laboratory services and the clinical usefulness of molecular genetic test reports for referred specimens.  相似文献   

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Using proteomic approach in cerebrospinal fluid (CSF) we identified pigment epithelium-derived factor (PEDF) and Haptoglobin (Hp) as putative markers that could discriminate between AD and other dementias. ELISA assays were developed to measure the levels of PEDF and Hp in CSF from patients with AD (AD, n?=?27), non-AD (NAD, n?=?30) and in non-demented patients (ND, n?=?27). The combined assessment of PEDF, Hp and Tau levels, using Iterative Marginal Optimization, improved the differential diagnosis of AD, especially in patients with moderate to severe dementia (p<0.002). This pilot study highlights the probable different contribution of oxidative mechanisms in dementia.  相似文献   

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Both body weight and educational attainment have risen in the United States. Empirical evidence regarding educational differences in obesity (BMI ≥30) is inconsistent. According to some widely cited claims, these differences have declined since the 1970s, and the most educated have experienced the greatest gain in obesity. Prior research was limited in grouping college graduates with nongraduates, combining men and women in the same analysis, and using self-reported rather than measured anthropometric information. Using the National Health and Nutrition Examination Surveys (NHANES), we address these issues and examine changing educational differences in obesity from 1971-1980 to 1999-2006 for non-Hispanic whites and blacks in two separate age groups (25-44 vs. 45-64 years). We find that (i) obesity differentials by education have remained largely stable, (ii) compared with college graduates, less educated whites and younger black women continue to be more likely to be obese, (iii) but the differentials are larger for women than men, and weak or nonexistent among black men and older black women. There are exceptions to the overall trend. The obesity gap has widened between the two groups of college-educated younger women, but disappeared between the least and most educated younger white men. Thus, the increase in obesity was similar for most educational groups, but significantly greater for younger women with some college and smaller for younger white men without a high-school degree. Lumping together the two distinct college groups has biased previous estimates of educational differences in obesity.  相似文献   

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Despite declining smoking rates in the U.S., a substantial fraction of adolescents still smoke. In addition, there are notable racial differences in adolescent smoking. We use Add Health data and apply a nonlinear decomposition method to determine the extent to which racial differences in observable characteristics account for (i) the racial smoking gaps in adolescent smoking (ages 12–18) and (ii) racial gaps in the probability of becoming a smoker in young adulthood (ages 18–24), conditional on being a non-smoker in adolescence. The model includes a host of explanatory factors, including individual, family socioeconomics, smoke exposure, school characteristics, and county crime rate. Of the 19 (9) percentage-point gap in white-black (white-Hispanic) smoking in adolescence, these factors together account for 22–28% (39–77%) of the smoking gap; and of the 18 (13) percentage-point gap in white-black (white-Hispanic) smoking up-take in young adulthood, these factors together account for 26–50% (48–100%) of the gap, depending on which set of coefficients are used for the decomposition. The biggest drivers of racial smoking gaps in adolescence are differences in friends’ smoking and school peer smoking, while only school peer smoking contributes to the explained portion of racial gaps in smoking up-take in young adulthood.  相似文献   

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On March 11, 2020 the World Health Organization classified COVID-19, caused by Sars-CoV-2, as a pandemic. Although not much was known about the new virus, the first outbreaks in China and Italy showed that potentially a large number of people worldwide could fall critically ill in a short period of time. A shortage of ventilators and intensive care resources was expected in many countries, leading to concerns about restrictions of medical care and preventable deaths. In order to be prepared for this challenging situation, national triage guidance has been developed or adapted from former influenza pandemic guidelines in an increasing number of countries over the past few months. In this article, we provide a comparative analysis of triage recommendations from selected national and international professional societies, including Australia/New Zealand, Belgium, Canada, Germany, Great Britain, Italy, Pakistan, South Africa, Switzerland, the United States, and the International Society of Critical Care Medicine. We describe areas of consensus, including the importance of prognosis, patient will, transparency of the decision-making process, and psychosocial support for staff, as well as the role of justice and benefit maximization as core principles. We then probe areas of disagreement, such as the role of survival versus outcome, long-term versus short-term prognosis, the use of age and comorbidities as triage criteria, priority groups and potential tiebreakers such as ‘lottery’ or ‘first come, first served’. Having explored a number of tensions in current guidance, we conclude with a suggestion for framework conditions that are clear, consistent and implementable. This analysis is intended to advance the ongoing debate regarding the fair allocation of limited resources and may be relevant for future policy-making.  相似文献   

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The honeybee, Apis mellifera, is an invaluable partner in agriculture around the world both for its production of honey and, more importantly, for its role in pollination. Honeybees are largely unexplored at the molecular level despite a long and distinguished career as a model organism for understanding social behavior. Like other eusocial insects, honeybees can be divided into several castes: the queen (fertile female), workers (sterile females), and drones (males). Each caste has different energetic and metabolic requirements, and each differs in its susceptibility to pathogens, many of which have evolved to take advantage of the close social network inside a colony. Hemolymph, arthropods' equivalent to blood, distributes nutrients throughout the bee, and the immune components contained within it form one of the primary lines of defense against invading microorganisms. In this study we have applied qualitative and quantitative proteomics to gain a better understanding of honeybee hemolymph and how it varies among the castes and during development. We found large differences in hemolymph protein composition, especially between larval and adult stage bees and between male and female castes but even between adult workers and queens. We also provide experimental evidence for the expression of several unannotated honeybee genes and for the detection of biomarkers of a viral infection. Our data provide an initial molecular picture of honeybee hemolymph, to a greater depth than previous studies in other insects, and will pave the way for future biochemical studies of innate immunity in this animal.  相似文献   

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Two British boarding schools for boys with different disciplinary policies in respect of cigarette smoking were identified. Questionnaires were sent to the young "old boys" of each school to determine their present smoking habit and most were returned (school A 81%, school B 83%). Significantly more responders smoked who had been to the less strict school (school A 39%, school B 30%, p less than 0.05). These figures probably underestimate the smoking prevalence in the two complete groups. The results suggest that measures that reduce the exposure of an uncommitted adolescent to peer group smoking decrease the chances of tobacco dependence in adulthood.  相似文献   

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BACKGROUND: While several algorithms for the comparison of univariate distributions arising from flow cytometric analyses have been developed and studied for many years, algorithms for comparing multivariate distributions remain elusive. Such algorithms could be useful for comparing differences between samples based on several independent measurements, rather than differences based on any single measurement. It is conceivable that distributions could be completely distinct in multivariate space, but unresolvable in any combination of univariate histograms. Multivariate comparisons could also be useful for providing feedback about instrument stability, when only subtle changes in measurements are occurring. METHODS: We apply a variant of Probability Binning, described in the accompanying article, to multidimensional data. In this approach, hyper-rectangles of n dimensions (where n is the number of measurements being compared) comprise the bins used for the chi-squared statistic. These hyper-dimensional bins are constructed such that the control sample has the same number of events in each bin; the bins are then applied to the test samples for chi-squared calculations. RESULTS: Using a Monte-Carlo simulation, we determined the distribution of chi-squared values obtained by comparing sets of events from the same distribution; this distribution of chi-squared values was identical as for the univariate algorithm. Hence, the same formulae can be used to construct a metric, analogous to a t-score, that estimates the probability with which distributions are distinct. As for univariate comparisons, this metric scales with the difference between two distributions, and can be used to rank samples according to similarity to a control. We apply the algorithm to multivariate immunophenotyping data, and demonstrate that it can be used to discriminate distinct samples and to rank samples according to a biologically-meaningful difference. CONCLUSION: Probability binning, as shown here, provides a useful metric for determining the probability with which two or more multivariate distributions represent distinct sets of data. The metric can be used to identify the similarity or dissimilarity of samples. Finally, as demonstrated in the accompanying paper, the algorithm can be used to gate on events in one sample that are different from a control sample, even if those events cannot be distinguished on the basis of any combination of univariate or bivariate displays. Published 2001 Wiley-Liss, Inc.  相似文献   

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BACKGROUND: Comparing distributions of data is an important goal in many applications. For example, determining whether two samples (e.g., a control and test sample) are statistically significantly different is useful to detect a response, or to provide feedback regarding instrument stability by detecting when collected data varies significantly over time. METHODS: We apply a variant of the chi-squared statistic to comparing univariate distributions. In this variant, a control distribution is divided such that an equal number of events fall into each of the divisions, or bins. This approach is thereby a mini-max algorithm, in that it minimizes the maximum expected variance for the control distribution. The control-derived bins are then applied to test sample distributions, and a normalized chi-squared value is computed. We term this algorithm Probability Binning. RESULTS: Using a Monte-Carlo simulation, we determined the distribution of chi-squared values obtained by comparing sets of events derived from the same distribution. Based on this distribution, we derive a conversion of any given chi-squared value into a metric that is analogous to a t-score, i.e., it can be used to estimate the probability that a test distribution is different from a control distribution. We demonstrate that this metric scales with the difference between two distributions, and can be used to rank samples according to similarity to a control. Finally, we demonstrate the applicability of this metric to ranking immunophenotyping distributions to suggest that it indeed can be used to objectively determine the relative distance of distributions compared to a single control. CONCLUSION: Probability Binning, as shown here, provides a useful metric for determining the probability that two or more flow cytometric data distributions are different. This metric can also be used to rank distributions to identify which are most similar or dissimilar. In addition, the algorithm can be used to quantitate contamination of even highly-overlapping populations. Finally, as demonstrated in an accompanying paper, Probability Binning can be used to gate on events that represent significantly different subsets from a control sample. Published 2001 Wiley-Liss, Inc.  相似文献   

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The effectiveness of command-and-control policies related to tobacco use has been studied in high-income countries. Still, there is limited evidence of their effects in low and middle-income countries. We explore the case of Colombia, a country that introduced a business-supported smoking ban in bars and restaurants and all public indoor spaces in 2010. This paper investigates the effect of smoking bans in bars and restaurants on smoking prevalence in Bogotá, Colombia. In this paper, we use the matching with triple-differences technique in analyzing household consumption data from the 2007 and 2011 quality of life surveys. This is done by exploiting their geographical proximity and variation in the density of commercial areas. We found that after the smoking ban implementation, smoking prevalence reduced in households near high-density commercial blocks compared to households near low-density commercial blocks (−10.8 pp.). The impact is larger for households with children and older household heads. Since households near high-density commercial blocks are more frequently exposed to smoking than households near low-density commercial blocks, the former would be more willing to internalize the smoking de-normalization process.  相似文献   

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The International HapMap Project is a resource for researchers containing genotype, sequencing, and expression information for EBV-transformed lymphoblastoid cell lines derived from populations across the world. The expansion of the HapMap beyond the four initial populations of Phase 2, referred to as Phase 3, has increased the sample number and ethnic diversity available for investigation. However, differences in the rate of cellular proliferation between the populations can serve as confounders in phenotype-genotype studies using these cell lines. Within the Phase 2 populations, the JPT and CHB cell lines grow faster (p < 0.0001) than the CEU or YRI cell lines. Phase 3 YRI cell lines grow significantly slower than Phase 2 YRI lines (p < 0.0001), with no widespread genetic differences based on common SNPs. In addition, we found significant growth differences between the cell lines in the Phase 2 ASN populations and the Han Chinese from the Denver metropolitan area panel in Phase 3 (p < 0.0001). Therefore, studies that separate HapMap panels into discovery and replication sets must take this into consideration.  相似文献   

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The sex difference in perinatal mortality in developed countries is largely unexplained. The current study evaluated the differences in the impact of maternal smoking during pregnancy on the risk of perinatal death between males and females. The analysis involved 11,469 and 9,404 newborns derived from two population-based birth cohorts in Northern Finland, for 1966 and 1985-86, respectively. The perinatal mortality rate was 23 per thousand in the 1966 cohort and 9 per thousand in the 1985-86 cohort. The rate ratio (RR) for mortality for males over females is 1.15 and 1.60 in the two cohorts, respectively. Among children whose mothers smoked during pregnancy, the RR was 2.2 (95% CI 1.0, 4.7) for the former cohort and 4.8 (95% CI 1.5, 15.2) for the later cohort; and among the children whose mothers did not smoke the corresponding RR was 1.2 (95% CI 0.9, 1.6) and 1.1 (95% CI 0.6, 1.9). Maternal smoking during pregnancy could be an important determinant accounting for the excess perinatal death for males over females. Our results encourage evaluation of the findings among other populations.  相似文献   

19.
Abstract

The sex difference in perinatal mortality in developed countries is largely unexplained. The current study evaluated the differences in the impact of maternal smoking during pregnancy on the risk of perinatal death between males and females. The analysis involved 11,469 and 9,404 newborns derived from two population‐based birth cohorts in Northern Finland, for 1966 and 1985–86, respectively. The perinatal mortality rate was 23 per thousand in the 1966 cohort and 9 per thousand in the 1985–86 cohort. The rate ratio (RR) for mortality for males over females is 1.15 and 1.60 in the two cohorts, respectively. Among children whose mothers smoked during pregnancy, the RR was 2.2 (95% CI 1.0, 4.7) for the former cohort and 4.8 (95% CI 1.5, 15.2) for the later cohort; and among the children whose mothers did not smoke the corresponding RR was 1.2 (95% CI 0.9, 1.6) and 1.1 (95% CI 0.6, 1.9). Maternal smoking during pregnancy could be an important determinant accounting for the excess perinatal death for males over females. Our results encourage evaluation of the findings among other populations.  相似文献   

20.
Box  Elgene O. 《Plant Ecology》2002,163(2):139-154
Biogeographic comparisons help to identify similarities, differences, larger contexts, and useful hypotheses. Between the (extra-tropical) Northern and Southern Hemispheres taxonomy differs almost completely, but other useful bases for vegetation comparison include phenophysiognomy, form composition and vegetation architecture, subphysiognomic morphology, environmental limits of plant types, taxonomic richness, and some aspects of function. All major biome types occur in both hemispheres except the boreal forests and analogous montane coniferous forests of the Northern Hemisphere. Some vegetation and plant types appear clearly unique, including Eucalyptus, campo cerrado, and flat-cushions such as Azorella, all of these in the Southern Hemisphere. Different but parallel adaptations to different but analogous conditions include the tall submediterranean forests, temperate rainforests, and continental versus maritime temperate deserts. Climatic limits appear similar in the two hemispheres, but mechanisms for some differences remain unresolved. Per unit land area, the Southern Hemisphere has higher annual net primary productivity than the Northern. Dissimilar analogs continue to suggest hypotheses and research questions.  相似文献   

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