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Purpose

The purpose of this study is to evaluate clinical outcomes from applications of contemporary social media in chronic disease; to develop a conceptual taxonomy to categorize, summarize, and then analyze the current evidence base; and to suggest a framework for future studies on this topic.

Methods

We performed a systematic review of MEDLINE via PubMed (January 2000 to January 2015) of studies reporting clinical outcomes on leading contemporary social media (ie, Facebook, Twitter, Wikipedia, YouTube) use in 10 chronic diseases. Two reviewers independently performed data extraction and quality assessment; characterization of study outcomes as positive, negative, neutral, or undefined impact; and inductive, thematic analysis to develop our taxonomy.

Results

Of 378 citations identified, 42 studies examining the use of Facebook (n = 16), blogs (n = 13), Twitter (n = 8), wikis (n = 5), and YouTube (n = 4) on outcomes in cancer (n = 14), depression (n = 13), obesity (n = 9), diabetes (n = 4), heart disease (n = 3), stroke (n = 2), and chronic lower respiratory tract infection (n = 1) were included. Studies were classified as support (n = 16), patient education (n = 10), disease modification (n = 6), disease management (n = 5), and diagnosis (n = 5) within our taxonomy. The overall impact of social media on chronic disease was variable, with 48% of studies indicating benefit, 45% neutral or undefined, and 7% suggesting harm. Among studies that showed benefit, 85% used either Facebook or blogs, and 40% were based within the domain of support.

Conclusions

Using social media to provide social, emotional, or experiential support in chronic disease, especially with Facebook and blogs, appears most likely to improve patient care.  相似文献   

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Content on Twitter’s home timeline is selected and ordered by personalization algorithms. By consistently ranking certain content higher, these algorithms may amplify some messages while reducing the visibility of others. There’s been intense public and scholarly debate about the possibility that some political groups benefit more from algorithmic amplification than others. We provide quantitative evidence from a long-running, massive-scale randomized experiment on the Twitter platform that committed a randomized control group including nearly 2 million daily active accounts to a reverse-chronological content feed free of algorithmic personalization. We present two sets of findings. First, we studied tweets by elected legislators from major political parties in seven countries. Our results reveal a remarkably consistent trend: In six out of seven countries studied, the mainstream political right enjoys higher algorithmic amplification than the mainstream political left. Consistent with this overall trend, our second set of findings studying the US media landscape revealed that algorithmic amplification favors right-leaning news sources. We further looked at whether algorithms amplify far-left and far-right political groups more than moderate ones; contrary to prevailing public belief, we did not find evidence to support this hypothesis. We hope our findings will contribute to an evidence-based debate on the role personalization algorithms play in shaping political content consumption.

Political content is a major part of the public conversation on Twitter. Politicians, political organizations, and news outlets engage large audiences on Twitter. At the same time, Twitter employs algorithms that learn from data to sort content on the platform. This interplay of algorithmic content curation and political discourse has been the subject of intense scholarly debate and public scrutiny (115). When first established as a service, Twitter used to present individuals with content from accounts they followed, arranged in a reverse chronological feed. In 2016, Twitter introduced machine learning algorithms to render tweets on this feed called Home timeline based on a personalized relevance model (16). Individuals would now see older tweets deemed relevant to them, as well as some tweets from accounts they did not directly follow.Personalized ranking prioritizes some tweets over others on the basis of content features, social connectivity, and user activity. There is evidence that different political groups use Twitter differently to achieve political goals (1720). What has remained a matter of debate, however, is whether or not any ranking advantage falls along established political contours, such as the left or right (2, 7), the center or the extremes (1, 3), specific parties (2, 7), or news sources of a certain political inclination (21). In this work, we provide systematic quantitative insights into this question based on a massive-scale randomized experiment on the Twitter platform.  相似文献   

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This study was designed to investigate the efficacy of a decongestant-antihistamine preparation in combination with antibiotic treatment of acute otitis media. The effectiveness of a new Dimetapp (DIM) preparation was assessed in comparison with each of its components (brompheniramine maleate [BPM] and phenylephrine hydrochloride [PEH] as well as a placebo (PL) vehicle in the treatment of acute otitis media. In a randomized double blind study, 98 children were treated in the emergency department or outpatient medical clinics at Children's Hospital of Michigan with amoxicillin and either DIM, BPM, PEH, or PL. They were evaluated at two weeks by clinical examination, pneumatoscopy, and tympanometry. Fifty-eight patients (59%) continued to have evidence of fluid in the middle ear. These patients were continued on the test medications for another two weeks and then reevaluated. There were significant differences between the treatment groups (DIM, BPM, and PEH) and the control PL group; the patients receiving Dimetapp or placebo fared better than those receiving BPM or PEH. However, there was no difference in the overall response between Dimetapp and placebo. Antihistamine-decongestant therapy does not appear to be necessary in the treatment of acute otitis media in children.  相似文献   

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Three cases of acute myeloblastic leukemia of FAB-M2 type revealed by an isolated otitis media are reported. This mean of revelation is valuable for early diagnosis and treatment of the disease. A karyotype was performed in two cases and showed an 8;21 translocation. As far as we know, these are the first acute myeloblastic leukemia cases with otitis media reported in which an 8;21 translocation was detected.  相似文献   

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Allergic reactions, including anaphylactoid shock due to contrast material, are not uncommon. However, persistent anaphylactoid shock refractory to conventional therapy is rare. We present a case of refractory anaphylactoid shock during coronary angiography unresponsive to aggressive standard therapy in a patient on beta-blockers. Significant clinical improvement was noted upon administration of glucagon. Since beta-blockers are commonly used in patients with coronary artery disease, this potentially life-threatening complication has to be kept in mind with any procedure involving contrast media in patients on beta-blockers. Immediate access to glucagon by keeping it in the procedure room may be lifesaving in these situations. © 1996 Wiley-Liss, Inc.  相似文献   

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目的:探讨拟行冠状动脉造影和(或)介入治疗患者,采用低渗对比剂与等渗对比剂对其肾功能的影响。方法:本研究为单中心、随机、单盲及前瞻性研究,选择2012年11月至2013年10月,于安贞医院接受冠状动脉造影和(或)介入治疗患者共302例,按数字表法随机分为甲、乙两组,其中甲组使用低渗对比剂共180例,乙组使用等渗对比剂共122例,甲组中肾功能正常者130例,肾功能减低者50例,乙组中肾功能正常者91例,肾功能减低者31例,总体比较两组患者对比剂肾病(contrast induced nephropathy,CIN)的发病率,及分别比较两组中肾功能正常及肾功能减低其CIN的发病率。结果:①在总体例群中,低渗组中CIN 11例(6.11%),等渗组中CIN 7例(5.74%),低渗组术后血肌酐值(serum creatinine,SCr)为(76.91±16.80)μmol/L,等渗组患者术后SCr为(78.68±22.98)μmol/L,均差异无统计学意义(P0.05)。②对于肾功能正常的亚组,术后SCr及CIN发病率差异无统计学意义。③对于肾功能减低的亚组,两组术后SCr差异无统计学意义。低渗组CIN患者7例(14%),等渗组CIN患者3例(9.7%),等渗组发病率显著低于低渗组。结论:在总体例群中,无论在术后SCr值,还是CIN的发病率,应用等渗对比剂与低渗对比剂差异无统计学意义。在肾功能减低的患者中,应用等渗对比剂其CIN的发病率明显少于低渗对比剂。  相似文献   

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The precise mechanisms by which the information ecosystem polarizes society remain elusive. Focusing on political sorting in networks, we develop a computational model that examines how social network structure changes when individuals participate in information cascades, evaluate their behavior, and potentially rewire their connections to others as a result. Individuals follow proattitudinal information sources but are more likely to first hear and react to news shared by their social ties and only later evaluate these reactions by direct reference to the coverage of their preferred source. Reactions to news spread through the network via a complex contagion. Following a cascade, individuals who determine that their participation was driven by a subjectively “unimportant” story adjust their social ties to avoid being misled in the future. In our model, this dynamic leads social networks to politically sort when news outlets differentially report on the same topic, even when individuals do not know others’ political identities. Observational follow network data collected on Twitter support this prediction: We find that individuals in more polarized information ecosystems lose cross-ideology social ties at a rate that is higher than predicted by chance. Importantly, our model reveals that these emergent polarized networks are less efficient at diffusing information: Individuals avoid what they believe to be “unimportant” news at the expense of missing out on subjectively “important” news far more frequently. This suggests that “echo chambers”—to the extent that they exist—may not echo so much as silence.

By standard measures, political polarization in the American mass public is at its highest point in nearly 50 y (1). The consequences of this fundamental and growing societal divide are potentially severe: High levels of polarization reduce policy responsiveness and have been associated with decreased social trust (2), acceptance of and dissemination of misinformation (3), democratic erosion (4), and in extreme cases even violence (5). While policy divides have traditionally been thought to drive political polarization, recent research suggests that political identity may play a stronger role (6, 7). Yet people’s political identities may be increasingly less visible to those around them: Many Americans avoid discussing and engaging with politics and profess disdain for partisanship (8), and identification as “independent” from the two major political parties is higher than at any point since the 1950s (9). Taken together, these conflicting patterns complicate simple narratives about the mechanisms underlying polarization. Indeed, how macrolevel divisions relate to the preferences, perceptions, and interpersonal interactions of individuals remains a significant puzzle.A solution to this puzzle is particularly elusive given that many Americans, increasingly wary of political disagreement, avoid signaling their politics in discussions and self-presentation and thus lack direct information about the political identities of their social connections (10). However, regardless of individuals’ perceptions about each other, the information ecosystem around them—the collection of news sources available to society—reflects, at least to some degree, the structural divides of the political and economic system (11, 12). Traditional accounts of media-driven polarization have emphasized a direct mechanism: Individuals are influenced by the news they consume (13) but also tend to consume news from outlets that align with their politics (14, 15), thereby reinforcing their views and shifting them toward the extremes (16, 17). However, large-scale behavioral studies have offered mixed evidence of these mechanisms (18, 19), including evidence that many people encounter a significant amount of counter-attitudinal information online (2022). Furthermore, instead of directly tuning into news sources, individuals often look to their immediate social networks to guide their attention to the most important issues (2327). Therefore, it is warranted to investigate how the information ecosystem may impact society beyond direct influence on individual opinions.Here, we examine media-driven polarization as a social process (28) and propose a mechanism—information cascades—by which a polarized information ecosystem can indirectly polarize society by causing individuals to self-sort into emergent homogeneous social networks even when they do not know others’ political identities. Information cascades, in which individuals observe and adopt the behavior of others, allow the actions of a few individuals to quickly propagate through a social network (29, 30). Found in social systems ranging from fish schools (31) and insect swarms (32) to economic markets (33) and popular culture (29), information cascades are a widespread social phenomenon that can greatly impact collective behavior such as decision making (34). Online social media platforms are especially prone to information cascades since the primary affordances of these services involve social networking and information sharing (3538): For example, users often see and share posts of social connections without ever reading the source material (e.g., a shared news article) (39). In addition to altering beliefs and behavior, information cascades can also affect social organization: For instance, retweet cascades on Twitter lead to bursts of unfollowing and following activity (40) that indicate sudden shifts in social connections as a direct result of information spreading through the social network. While research so far has been agnostic as to the content of the information shared during a cascade, it is plausible that information from partisan news outlets could create substantial changes in networks of individuals.We therefore propose that the interplay between network-altering cascades and an increasingly polarized information ecosystem could result in politically sorted social networks, even in the absence of partisan cues. While we do not argue that this mechanism is the only driver of political polarization—a complex phenomenon likely influenced by several factors—we do argue that the interplay between information and social organization could be one driver that is currently overlooked in discussions of political polarization. We explore this proposition by developing a general theoretical model. After presenting the model, we use Twitter data to probe some of its predictions. Finally, we use the model to explore how the emergence of politically sorted networks might alter information diffusion.  相似文献   

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Since the 2016 US presidential election, the deliberate spread of misinformation online, and on social media in particular, has generated extraordinary concern, in large part because of its potential effects on public opinion, political polarization, and ultimately democratic decision making. Recently, however, a handful of papers have argued that both the prevalence and consumption of “fake news” per se is extremely low compared with other types of news and news-relevant content. Although neither prevalence nor consumption is a direct measure of influence, this work suggests that proper understanding of misinformation and its effects requires a much broader view of the problem, encompassing biased and misleading—but not necessarily factually incorrect—information that is routinely produced or amplified by mainstream news organizations. In this paper, we propose an ambitious collective research agenda to measure the origins, nature, and prevalence of misinformation, broadly construed, as well as its impact on democracy. We also sketch out some illustrative examples of completed, ongoing, or planned research projects that contribute to this agenda.  相似文献   

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The effects of temperature on the stability of two contrast agents, Albunex and perfluoropropane filled albumin microspheres (FS069), were investigated by studying the variations in their reflective properties, induced by high dose ultrasound irradiation at different temperatures. Diluted contrast agents were introduced into a 3.5-mL latex balloon, placed in a plastic water tank, and continuously irradiated over a period of 6 minutes using different power levels: 0, 20, 25, and 30 dB. The irradiation was interrupted for imaging every 30 seconds for 2 seconds. The protocol was carried out at three different temperatures: 8°C, 22°C, and 37°C. For each temperature, the concentration of contrast solution was matched to produce approximately the same initial video intensity. Time variations in mean video intensity in the balloon cross section were studied. Contrast enhancement was found to be directly related to temperature. Under continuous ultrasonic irradiation, video intensity gradually decreased over time. This decrease was dependent on both transmitted power and temperature, and was more pronounced with Albunex when compared to FS069 (P < 0.05). Abruptly dropping temperature consistently resulted in rapid, irreversible disappearance of contrast induced by Albunex. Temperature affects the reflectivity and stability of diluted Albunex and FS069. To enhance the reproducibility of contrast enhancement achieved by these agents, their temperature should be carefully controlled.  相似文献   

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目的研究非离子型低渗造影剂诱导体外培养大鼠肾小球内皮细胞凋亡的作用,以及对凋亡蛋白Bcl-2和BaxmRNA表达的影响。方法不同浓度和时间的碘佛醇(Ioversol)作用于体外培养的大鼠肾小球内皮细胞,用噻唑蓝(MTT)法检测细胞存活率。用倒置显微镜观察碘佛醇作用24h后细胞形态学变化,用DNA凝胶电泳分析细胞凋亡。采用半定量RT-PCR研究碘佛醇作用前后Bcl-2和BaxmRNA的表达变化。结果非离子型低渗造影剂碘佛醇能显著降低大鼠肾小球内皮细胞存活率,并呈剂量和时间依赖性。肾小球内皮细胞在90mL碘佛醇培养液(每升细胞培养液中含90mL碘佛醇)中培养24h后皱缩、变圆、漂浮,DNA凝胶电泳呈现典型的凋亡梯度。RT-PCR结果提示,Bcl-2mRNA表达降低,BaxmRNA表达升高,BaxmRNA/Bcl-2mRNA比值明显增加。结论非离子型低渗造影剂能够通过Bcl-2/Bax基因表达变化诱导肾小球内皮细胞凋亡,该机制可能与造影剂肾病的发生有关。  相似文献   

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Biofilms are antibiotic-resistant, sessile bacterial communities that occupy most moist surfaces on Earth and cause chronic and medical device-associated infections. Despite their importance, basic information about biofilm dynamics in common ecological environments is lacking. Here, we demonstrate that flow through soil-like porous materials, industrial filters, and medical stents dramatically modifies the morphology of Pseudomonas aeruginosa biofilms to form 3D streamers, which, over time, bridge the spaces between obstacles and corners in nonuniform environments. We discovered that accumulation of surface-attached biofilm has little effect on flow through such environments, whereas biofilm streamers cause sudden and rapid clogging. We demonstrate that flow-induced shedding of extracellular matrix from surface-attached biofilms generates a sieve-like network that captures cells and other biomass, which add to the existing network, causing exponentially fast clogging independent of growth. These results suggest that biofilm streamers are ubiquitous in nature and strongly affect flow through porous materials in environmental, industrial, and medical systems.  相似文献   

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A large body of research confirms that food advertising affects the food preferences and behaviour of children. The impact of food advertising on adults is less clear. We conducted a systematic review exploring the effects of advertising of food and non‐alcoholic drinks (referred to as ‘food’ throughout) on food‐related behaviour, attitudes and beliefs in adult populations. We searched seven electronic databases, grey literature sources, and references and citations of included material for experimental studies written in English investigating the effects of commercial food advertising on the food‐related behaviours, attitudes and beliefs of adults aged 16 years and over. Nine studies, rated moderate to poor quality, were included in the review; all were from developed countries and explored the impact of televised food advertising. Overall, the results did not show conclusively whether or not food advertising affects food‐related behaviour, attitudes or beliefs in adults, but suggest that the impact varies inconsistently within subgroups, including gender, weight and existing food psychology. The identification of a small number of relevant studies, none of which were high quality, and with substantial heterogeneity, highlights the need for further research. Future studies investigating longer term outcomes, diverse advertising formats, and in countries with different levels of economic development will be of particular value.  相似文献   

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目的:探讨不同水化途径对造影剂肾病影响。方法:525例拟行血管造影术患者,随机分为经口、外周静脉、锁骨下静脉途径三组,每组175例,术前6h、术后6~8h分别通过上述三种途径补充生理盐水2000ml,观察三组患者术前、术后1~5d尿量、内生肌酐清除率(Ccr),血、尿β2-MG水平变化,同时行心脏超声评价心功能的变化。结果:(1)与术前比较,三组术后24h平均尿量、Ccr均有明显增加,血、尿肌酐,血、尿β2-MG水平明显下降;(2)与经口途径组、外周静脉组比较,锁骨下静脉组术后24h平均尿量[(1875.23±29.31)ml比(1987.65±35.95)ml比(2213.26±26.47)ml]、Ccr[(85.43±1.52)ml/min比(73.63±1.24)ml/min比(89.85±2.35)ml/min]水平明显增加,P均〈0.05;(3)所有患者Ccr逐渐恢复至术前水平,锁骨下静脉途径组术后第3日恢复术前水平,恢复最快,经口途径组术后第5日尚未恢复术前水平,恢复最慢。结论:三种不同水化途径均可有效预防、治疗造影剂肾病,但锁骨下静脉途径肾功能恢复最快,效果最好。  相似文献   

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目的观察冠心病患者冠状动脉造影(CAG)及经皮冠状动脉介入(PCI)术前与术后血清中性粒细胞明胶酶相关脂质运载蛋白(NGAL)水平变化,探讨NGAL预测对比剂肾病(CIN)的价值。方法回顾性分析南京医科大学第二附属医院心血管内科和急诊中心2017年4月至2018年4月行CAG和PCI术的患者136例,根据术后是否发生CIN,将患者分为CIN组(10例)和非CIN组(126例),比较2组患者术前、术后24 h和48 h血肌酐(SCr)、尿素氮(BUN)以及NGAL水平并分析NGAL预测CIN的价值。采用SPSS 22.0统计软件对数据进行分析。组间比较采用t检验、方差分析或χ~2检验。绘制受试者工作特征曲线(ROC)分析血清NGAL水平对CIN的预测价值。结果 CIN组患者术后48 h SCr、24 h BUN、48 h BUN和24 h NGAL水平相比术前增高,差异有统计学意义(P0.05)。相比非CIN组患者,CIN组患者术后48 h SCr[(174.95±15.77)vs(97.69±9.33)μmol/L]、24 h BUN[(7.75±1.75)vs(5.07±1.35)mmol/L]、48 h BUN[(8.92±2.03)vs(5.17±1.31)mmol/L]、术前NGAL[(341.08±205.69)vs(186.98±83.08)ng/ml]和术后24 h NGAL[(457.68±220.69)vs(185.82±51.41)ng/ml]水平增高,差异均具有统计学意义(P0.05)。ROC曲线显示术后24 h NGAL水平预测CIN截断点为40.325 ng/ml,曲线下面积为0.852,灵敏度70%,特异度100%。结论冠心病患者PCI和CAG术后24 h血清NGAL水平明显升高,有早期预测CIN价值。  相似文献   

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