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1.
As millions of people turn to social media for health information, better understanding the factors that guide health-related judgments and perceptions in this context is imperative. We report on two Web experiments (n > 400 total) examining the power of society’s widespread weight bias and related stereotypes to influence nutrition judgments in social media spaces. In Experiment 1, meals were judged as lower in nutritional quality when the person who recommended them (the source) was depicted as obese rather than of normal weight, an effect mediated by stereotypic beliefs about the source as a generally unhealthy person. Experiment 2 replicated this effect, which—notably—remained significant when controlling for objective nutritional information (calories and fat content). Results highlight spillover effects of weight bias that extend beyond person perception to color impressions of objects (here, food) that are associated with stigmatized attributes. Implications for everyday nutrition judgments and public health are considered. 相似文献
2.
3.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
4.
The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity 总被引:20,自引:6,他引:20
Hughes CM; Lewis SE; McKelvey-Martin VJ; Thompson W 《Human reproduction (Oxford, England)》1998,13(5):1240-1247
The integrity of sperm DNA is crucial for the maintenance of genetic
health. A major source of damage is reactive oxygen species (ROS)
generation; therefore, antioxidants may afford protection to sperm DNA. The
objectives of the study were, first, to measure the effects of antioxidant
supplementation in vitro on endogenous DNA damage in spermatozoa using the
single cell gel electrophoresis (comet) assay and, second, to assess the
effect of antioxidant supplementation given prior to X-ray irradiation on
induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll
centrifugation in the presence of ascorbic acid (300, 600 microM), alpha
tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,
10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand
breakage was measured using the comet assay. Sperm DNA was protected from
DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60
microM) and urate (400 microM). These antioxidants provided protection from
subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or
ascorbate and alpha tocopherol together induced further DNA damage.
Supplementation in vitro with the antioxidants ascorbate, urate and alpha
tocopherol separately has beneficial effects for sperm DNA integrity.
相似文献
5.
How to use Chlamydia antibody testing in subfertility patients 总被引:1,自引:9,他引:1
Screening for tubal factor subfertility by means of Chlamydia antibody
testing (CAT) was introduced into the initial work-up of subfertile couples
several years ago. The results reported, however, are heterogeneous, and no
uniformity exists in cut-off levels of titres, or in definitions of tubal
factor subfertility. We performed a prospective cohort study to evaluate
the implications of varying the definitions of tubal pathology and of
modifying the cut-off levels on the clinical impact of CAT in predicting
tubal factor subfertility. In 227 consecutive patients who attended our
fertility clinic, the Chlamydia IgG antibody titre was determined and
related to tuboperitoneal abnormalities at laparoscopy as a reference
standard. According to received operating characteristic (ROC) curve
analysis, a titre of 16 is the optimum cut-off level. Increasing the
cut-off level improves specificity and positive likelihood ratio (LR+), at
the expense of sensitivity and negative LR (LR-). Changing the definition
of tubal factor subfertility from unspecified tuboperitoneal abnormalities
into extensive adhesions and/or bilateral distal tubal occlusion improves
LR+, LR- and kappa significantly. We conclude that CAT is more accurate in
predicting severe distal tubal pathology than unspecified tuboperitoneal
abnormalities. Although from a statistical point of view a titre of 16 is
the optimum cut-off level, from a clinical point of view 32 or 64 may be
preferable, depending on the aim of screening and the inception cohort.
相似文献
6.
Annice Kim James Nonnemaker Jamie Guillory Paul Shafer Sarah Parvanta John Holloway 《Journal of health communication》2017,22(6):477-487
Efforts are underway to educate consumers about the dangers of smoking at the point of sale (POS). Research is limited about the efficacy of POS antismoking ads to guide campaign development. This study experimentally tests whether the type of antismoking ad and the context in which ads are viewed influence people’s reactions to the ads. A national convenience sample of 7,812 adult current smokers and recent quitters was randomized to 1 of 39 conditions. Participants viewed one of the four types of antismoking ads (negative health consequences—graphic, negative social consequences—intended emotive, benefits of quitting—informational, benefits of quitting—graphic) in one of the three contexts (alone, next to a cigarette ad, POS tobacco display). We assessed participants’ reactions to the ads, including perceived effectiveness, negative emotion, affective dissonance, and motivational reaction. Graphic ads elicited more negative emotion and affective dissonance than benefits of quitting ads. Graphic ads elicited higher perceived effectiveness and more affective dissonance than intended emotive ads. Antismoking ads fared best when viewed alone, and graphic ads were least influenced by the context in which they were viewed. These results suggest that in developing POS campaigns, it is important to consider the competitive pro-tobacco context in which antismoking ads will be viewed. 相似文献
7.
Mika VJ Mustonen Seppo Pyrh?nen Pirkko-Liisa Kellokumpu-Lehtinen 《World journal of clinical oncology》2014,5(3):393-405
Although more widespread screening and routine adjuvant therapy has improved the outcome for breast cancer patients in recent years, there remains considerable scope for improving the efficacy, safety and tolerability of adjuvant therapy in the early stage disease and the treatment of advanced disease. Toremifene is a selective estrogen receptor modifier (SERM) that has been widely used for decades in hormone receptor positive breast cancer both in early and late stage disease. Its efficacy has been well established in nine prospective randomized phase III trials compared to tamoxifen involving more than 5500 patients, as well as in several large uncontrolled and non-randomized studies. Although most studies show therapeutic equivalence between the two SERMs, some show an advantage for toremifene. Several meta-analyses have also confirmed that the efficacy of toremifene is at least as good as that of tamoxifen. In terms of safety and tolerability toremifene is broadly similar to tamoxifen although there is some evidence that toremifene is less likely to cause uterine neoplasms, serious vascular events and it has a more positive effect on serum lipids than does tamoxifen. Toremifene is therefore effective and safe in the treatment of breast cancer. It provides not only a useful therapeutic alternative to tamoxifen, but may bring specific benefits. 相似文献
8.
Jamie Guillory Michael Johns Shannon M. Farley Pamela M. Ling 《American journal of public health》2015,105(8):e140-e147
Objectives. We examined loose cigarette (loosie) purchasing behavior among young adult (aged 18–26 years) smokers at bars in New York City and factors associated with purchase and use.Methods. Between June and December 2013, we conducted cross-sectional surveys (n = 1916) in randomly selected bars and nightclubs. Using multivariable logistic regression models, we examined associations of loose cigarette purchasing and use with smoking frequency, price, social norms, cessation behaviors, and demographics.Results. Forty-five percent (n = 621) of nondaily smokers and 57% (n = 133) of daily smokers had ever purchased a loosie; 15% of nondaily smokers and 4% of daily smokers reported that their last cigarette was a loosie. Nondaily smokers who never smoked daily were more likely than were daily smokers to have last smoked a loosie (odds ratio = 7.27; 95% confidence interval = 2.35, 22.48). Quitting behaviors and perceived approval of smoking were associated with ever purchasing and recently smoking loosies.Conclusions. Loosie purchase and use is common among young adults, especially nondaily smokers. Smoking patterns and attitudes should be considered to reduce loose cigarette purchasing among young adults in New York City.Widespread adoption of clean indoor air laws and cigarette tax increases denormalize smoking behavior1 and decrease smoking rates.2,3 Although increasing taxes is one of the most effective means of smoking prevention and reduction,3 the increased price of cigarettes can also lead to tax-avoidant behaviors, such as buying untaxed packs smuggled from states with lower cigarette taxes and purchasing loose cigarettes, or “loosies.”4–6 In New York City (NYC), where a cigarette pack costs about $11.50, it has become common for smokers to purchase discounted packs and individual cigarettes from street peddlers and friends.7,8Much of the research exploring loosie purchasing in the United States has focused on underage or low-income minority populations, often in urban areas.7,9,10 One study found that in early 1993, 70% of stores in central Harlem sold loosies to minors.7 Another study conducted with a 2005–2006 convenience sample in inner-city Baltimore found that 77% of African American smokers aged 18 to 24 years had purchased loosies in the past month.11 Similarly, loosie purchasing in Mexico was more common among younger smokers with lower incomes.12Availability and visibility of loosies can promote smoking and encourage relapse.13 We defined nondaily smokers as those who smoked on 1 to 29 of the past 30 days.14,15 Shiffman et al. found that nondaily smokers were more likely than daily smokers to report that social and environmental stimuli motivated their smoking behavior.16 More specifically, cues such as taste, smell, social goading to smoke, and specific situations (e.g., smoking after meals) are more likely to be reported as motivators to smoke by nondaily smokers than by daily smokers.16 Because social–environmental cues have substantial impact on nondaily smokers’ motivation to smoke, it is likely that the cue of seeing loosies in one’s environment also motivates nondaily smokers to smoke.16Previous research substantiates this claim, with 1 study showing that people who regularly saw loosies available for purchase were more likely to be current smokers.17 Therefore, the widespread availability of loosies may have a greater impact on nondaily smokers. Nondaily smokers make up a third of US smokers,18,19 and nondaily smoking is increasingly common among young adults.20 Many young adults who smoke on only some days do not self-identify as smokers,21 and nondaily smoking is frequently paired with alcohol consumption.22–24 Nondaily and light smoking carry a lower, but substantial, risk for lung cancer and a similar risk as does daily smoking for cardiovascular disease.25–27 Occasional smokers also have higher smoking-related morbidity and mortality than do people who have never smoked.26,28–30Nondaily smoking can be a long-term behavior pattern31,32 or a transition to or from daily smoking.31 Nondaily smokers include different subgroups that may have very different smoking patterns or motivations to quit.33,34 Nondaily smokers who previously smoked daily have been defined in previous research as converted nondaily smokers. Nondaily smokers who have never smoked daily are defined as native nondaily smokers.18,19 Important differences exist between these subgroups of smokers: converted nondaily smokers are more likely to quit smoking than are native nondaily smokers and daily smokers,18,19 although most converted and native nondaily smokers were unable to remain abstinent for more than 90 days.19Loosie purchasing and use may play an important role in promoting continued tobacco use among nondaily smokers. The 2010 NYC Community Health Survey35 found that more than one third (34%) of young adult nondaily smokers (aged 18–26 years) reported that their last cigarette smoked was a loosie, compared with 14% of young adult daily smokers. Another study of NYC adults demonstrated that nondaily smokers were more likely to purchase loose cigarettes than were light and heavy smokers.36 To the best of our knowledge, little is known about the factors associated with loosie purchasing among nondaily smokers in the United States.We sought to better understand the factors associated with loosie purchasing among NYC young adults, specifically to determine (1) loosie purchase and use rates among converted nondaily, native nondaily, and daily smokers; (2) whether loosie purchase or use are associated with perceived social norms of smoking behavior; and (3) whether loosie purchasing is associated with smoking cessation intention or behavior. 相似文献
9.
von Willebrand factor released from Weibel-Palade bodies binds more avidly to extracellular matrix than that secreted constitutively 总被引:8,自引:5,他引:8
Large multimers of von Willebrand factor (vWf) are released from the Weibel-Palade bodies of cultured endothelial cells following treatment with a secretagogue (Sporn et al, Cell 46:185, 1986). These multimers were shown by immunofluorescent staining to bind more extensively to the extracellular matrix of human foreskin fibroblasts than constitutively secreted vWf, which is composed predominantly of dimeric molecules. Increased binding of A23187-released vWf was not due to another component present in the releasate, since releasate from which vWf was adsorbed, when added together with constitutively secreted vWf, did not promote binding. When iodinated plasma vWf was overlaid onto the fibroblasts, the large forms bound preferentially to the matrix. These results indicated that the enhanced binding of the vWf released from the Weibel-Palade bodies was likely due to its large multimeric size. It appears that multivalency is an important component of vWf interaction with the extracellular matrix, just as has been shown for vWf interaction with platelets. The pool of vWf contained within the Weibel-Palade bodies, therefore, is not only especially suited for platelet binding, but also for interaction with the extracellular matrix. 相似文献
10.
Detection of circulating crosslinked fibrin derivatives by a heat extraction-SDS gradient gel electrophoretic technique 总被引:2,自引:1,他引:2
A technique has been developed to identify and quantitate unique plasmic degradation products of crosslinked fibrin in plasma. In this method, fibrin derivatives are extracted by heat precipitation and dissolved with disulfide bond reduction, after which the crosslinked gamma-gamma chain remnants are identified by SDS-polyacrylamide gradient gel electrophoresis and quantitated by densitometric analysis. A heterogenous group of gamma-gamma chains with molecular weights between 100,000 and 76,000 daltons was identified in lysates of crosslinked fibrin during plasmic degradation in vitro. Three stages of crosslinked fibrin degradation have been arbitrarily defined based primarily on the extent of degradation of these gamma-gamma polypeptide chains. As little as 20 microgram of crosslinked fibrin digests added to 1 ml of normal plasma could be detected by the heat-extraction--gel- electrophoresis technique, identifying the gamma-gamma derivatives with molecular weights of 96,000, 86,000, 82,000, and 76,000 daltons. Plasmic derivatives of gamma-gamma chains were not found in normal plasma, but they were identified in the plasma of patients with disseminated intravascular coagulation and deep-vein thrombosis, both before and in increased quantity during successful thrombolytic therapy. 相似文献