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Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/−, p53−/−) and Hd-rR HNI hybrid (p53+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/− fish than in p53−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.  相似文献   
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Pure Sertoli cell tumors are an uncommon variant of rare ovarian Sertoli‐Leydig cell tumors. Due to nonspecific clinical and imaging features, diagnosis is often made after histopathological examination. The prognosis is excellent as most are detected in the early stages and surgical resection is often curative in most cases.  相似文献   
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The pulmonary valve is the least affected site for valvular papillary fibroelastoma. With increasing use of routine echocardiography and other modalities of imaging, pulmonary valve papillary fibroelastomas (PVPFE) are being recognized more frequently. PVPFE is more often an incidental diagnosis and symptomatic patients usually present with shortness of breath. Embolic phenomena and right ventricular outflow tract obstruction are the most serious complications of PVPFE. Since PVPFE is rare, the purpose of this systematic review is to address demographic characteristics, the clinical presentation, management, and outcome of this benign tumor of the pulmonary valve.  相似文献   
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Objectives. We examined the associations among zip code demographics, the state alcohol policy environment, and the retail outlet availability of multiple fruit-flavored alcoholic drinks in a can (MFAC).Methods. In a nationally representative sample of zip codes (n = 872), we merged data from 4 sources: publicly available marketing information from 2 major MFAC producers, the US Census Bureau, state alcohol regulatory agencies, and recent research on state alcohol policies. We used zero-inflated negative binomial regression models to examine MFAC outlet availability in the United States.Results. More than 98% of MFAC outlets were off-premises alcohol establishments. After we controlled for population size and the number of licensed on- and off-premises alcohol outlets within zip codes, more families below the poverty line and weaker state alcohol control policies were associated with greater MFAC outlet availability.Conclusions. Economic conditions and alcohol policy environment appeared to be related to MFAC outlet availability, after adjusting for the general availability of alcohol. Research is needed to determine whether MFACs are disproportionately contributing to alcohol-related harm in socially and economically disadvantaged communities. Policies to better regulate the off-premises sale of alcohol are needed.In 2003, the first premixed caffeinated alcohol product was introduced in the United States, and by 2010 at least 8 brands of caffeinated alcohol were being sold.1,2 Released in August 2008, Four Loko became the most popular of these ready-to-drink products among underage drinkers.3,4 Anecdotal news and scientific reports linked Four Loko consumption to a number of dangerous drinking episodes, and as a result, questions were raised about its safety.5–7In addition to gaining the attention of the attorney generals of several states,8 by 2010, an emerging body of research began to show that caffeine–alcohol co-ingestion could produce elevated intoxication levels and reduce perceptions of impairment, and that drinkers could engage in riskier behaviors compared with the consumption of alcohol alone.9–14 Based on this research, the Federal Trade Commission and the Food and Drug Administration concluded that the combined high alcohol and high caffeine content of these premixed products was likely causing consumer harm.1,15 In response to pressure from the government, producers of products such as Four Loko and Joose voluntarily ceased production of these caffeinated drinks in November 2010.3 However, shortly thereafter, these producers began distributing reformulated products that no longer contained caffeine, guarine, and taurine.3,16,17Although the presence of a significant amount of caffeine likely played a role in producing injury and death, other characteristics of these products also likely contributed to hazardous alcohol consumption.18 Namely, their exceptionally high alcohol content, low price, fruit flavoring, colorful packaging, and targeted marketing may be responsible for attracting underage and lower socioeconomic consumers, and may continue to contribute to high-risk drinking among these groups.18,19 The combination of these product features led to Four Loko, Joose, and other similar beverages being labeled as multiple fruit-flavored alcoholic drinks in a can (MFAC) or supersized alcopops. Although alcopops contain similar fruit flavoring, MFACs are packaged in large, single-serving cans rather than in multiunit packs, they have higher alcohol content, and they cost less per standard drink, distinguishing them from alcopops.18 MFAC products are typically high in alcohol concentration (12%) and combined with large-sized containers (23.5 fluid ounces) result in that a single container, which is typically consumed immediately as 1 drink, actually contains 5 standard drinks.18 Moreover, the typical price is only $2.50 to $3.00, representing one of the lowest costs per dose of alcohol.18,19 There is limited research on MFAC products. Drug Abuse Warning Network data20 indicated that, in 2010, when Four Loko was primarily sold as a caffeinated product, there were an estimated 1242 hospital emergency department visits in the United States by persons who had consumed Four Loko (95% confidence interval = 332, 2152).21 However, in 2011, the first year Four Loko was sold without caffeine, the estimated Four Loko–related emergency department visits increased by nearly 4.5 times, to a total of 5492 (95% confidence interval = 2925, 8059).21 This substantial increase in emergency department visits suggests that Four Loko continues to be a health threat, despite the removal of caffeine. However, Four Loko was the only MFAC brand reported by the Drug Abuse Warning Network. Furthermore, a national survey conducted in 2012 found that approximately 6% of underaged drinkers consumed a Four Loko in the past 30 days, whereas consumption of other MFACs (e.g., Blast, Sparks, and Tilt) was less common.4Even less is known about the marketing and retail availability of MFAC products. One important question is whether the potential harms associated with MFAC consumption are borne evenly by all segments of society. The targeted marketing of potentially harmful products to vulnerable populations (e.g., low-income minority communities and communities with high proportions of youths) raises ethical concerns about social justice and corporate social responsibility.22Our purpose in this study was to test 2 hypotheses about MFAC outlet availability in the United States. First, we expected to find that zip code areas in states with stronger alcohol control environments (i.e., more laws, regulations, and practices designed to reduce excessive alcohol use and related harm) would have less MFAC availability. We expected this association because the combined effects of multiple concurrent alcohol policies in an overall alcohol policy environment helps shape local norms regarding alcohol use. For example, harsh penalties for supplying alcohol to underage drinkers or using or accepting fake identification may influence local alcohol marketing practices (i.e., products presumed to be higher risk might not be as heavily supplied or demanded in such areas). Second, we anticipated that zip code areas with greater poverty and a larger concentration of racial/ethnic minority persons would have greater MFAC outlet availability. The relatively low price of MFACs might make the products particularly appealing to economically disadvantaged communities.18,19 This notion was supported by previous research on malt liquor, another low-price, high-alcohol content, ready-to-drink product that was heavily marketed to and had greater retail availability in low-income minority communities.23–25 However, to date, there has been no systematic inquiry into these concerns with regard to MFAC products.  相似文献   
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