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31.
L Meghan Mahoney Tang Tang Kai Ji Jessica Ulrich-Schad 《JMIR Public Health and Surveillance》2015,1(1)
Background
New media changes the dissemination of public health information and misinformation. During a guest appearance on the Today Show, US Representative Michele Bachmann claimed that human papillomavirus (HPV) vaccines could cause “mental retardation”.Objective
The purpose of this study is to explore how new media influences the type of public health information users access, as well as the impact to these platforms after a major controversy. Specifically, this study aims to examine the similarities and differences in the dissemination of news articles related to the HPV vaccination between Google News and Twitter, as well as how the content of news changed after Michele Bachmann’s controversial comment.Methods
This study used a purposive sampling to draw the first 100 news articles that appeared on Google News and the first 100 articles that appeared on Twitter from August 1-October 31, 2011. Article tone, source, topics, concerns, references, publication date, and interactive features were coded. The intercoder reliability had a total agreement of .90.Results
Results indicate that 44.0% of the articles (88/200) about the HPV vaccination had a positive tone, 32.5% (65/200) maintained a neutral tone, while 23.5% (47/200) presented a negative tone. Protection against diseases 82.0% (164/200), vaccine eligibility for females 75.5% (151/200), and side effects 59.0% (118/200) were the top three topics covered by these articles. Google News and Twitter articles significantly differed in article tone, source, topics, concerns covered, types of sources referenced in the article, and uses of interactive features. Most notably, topic focus changed from public health information towards political conversation after Bachmann’s comment. Before the comment, the HPV vaccine news talked more often about vaccine dosing (P<.001), duration (P=.005), vaccine eligibility for females (P=.03), and protection against diseases (P=.04) than did the later pieces. After the controversy, the news topic shifted towards politics (P=.01) and talked more about HPV vaccine eligibility for males (P=.01).Conclusions
This longitudinal infodemiology study suggests that new media influences public health communication, knowledge transaction, and poses potential problems in the amount of misinformation disseminated during public health campaigns. In addition, the study calls for more research to adopt an infodemiology approach to explore relationships between online information supply and public health decisions. 相似文献32.
Left ventricular mass and exercise responses predict future blood pressure. The Muscatine Study 总被引:3,自引:0,他引:3
Increased blood pressure and left ventricular mass are associated with increased morbidity and mortality in adults with coronary heart disease. To define the predictors of subsequent childhood blood pressure and left ventricular mass, serial echocardiograms and blood pressure responses during exercise were studied in 274 children aged 6 to 15 years, whose systolic blood pressures were in the high, middle, or low range. Persistence of rank order for left ventricular mass and blood pressure, at rest and during exercise, was maintained over a mean follow-up period of 3.4 years, with correlations ranging from 0.33 to 0.44. Subsequent systolic blood pressure was best predicted from initial resting and maximal exercise systolic blood pressures and left ventricular mass. Subsequent left ventricular mass was best predicted from initial left ventricular mass and maximal exercise diastolic blood pressure, but resting systolic blood pressure did not add to this latter prediction. Since left ventricular mass relates best to exercise blood pressure and not to resting blood pressure, left ventricular mass may provide an integrated view of the effects of blood pressure both at rest and during stress. We speculate that increased left ventricular mass in childhood may be an important predictor of subsequent hypertension and its consequences. 相似文献
33.
Mahoney TR Luo S Round EK Brauner M Gottschalk A Thomas JH Nonet ML 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(42):16350-16355
The Caenorhabditis elegans defecation motor program (DMP) is a highly coordinated rhythmic behavior that requires two GABAergic neurons that synapse onto the enteric muscles. One class of DMP mutants, called anterior body wall muscle contraction and expulsion defective (aex) mutants, exhibits similar defects to those caused by the loss of these two neurons. Here, we demonstrate that aex-2 encodes a G-protein-coupled receptor (GPCR) and aex-4 encodes an exocytic SNAP25 homologue. We found that aex-2 functions in the nervous system and activates a G(s)alpha signaling pathway to regulate defecation. aex-4, on the other hand, functions in the intestinal epithelial cells. Furthermore, we show that aex-5, which encodes a pro-protein convertase, functions in the intestine to regulate the DMP and that its secretion from the intestine is impaired in aex-4 mutants. Activation of the G(s)alpha GPCR pathway in GABAergic neurons can suppress the defecation defect of the intestinal mutants aex-4 and aex-5. Lastly, we demonstrate that activation of GABAergic neurons using the light-gated cation channel channelrhodopsin-2 is sufficient to suppress the behavioral defects of aex-2, aex-4, and aex-5. These results genetically place intestinal genes aex-4 and aex-5 upstream of GABAergic GPCR signaling. We propose a model whereby the intestinal genes aex-4 and aex-5 control the DMP by regulating the secretion of a signal, which activates the neuronal receptor aex-2. 相似文献
34.
35.
Localization of human factor FVIII inhibitor epitopes to two polypeptide fragments. 总被引:9,自引:3,他引:9 下载免费PDF全文
C A Fulcher S de Graaf Mahoney J R Roberts C K Kasper T S Zimmerman 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(22):7728-7732
Epitopes for 22 alloantibodies that inhibit factor VIII procoagulant protein (FVIII) from multitransfused individuals with severe hemophilia A and three autoantibodies from nonhemophilic individuals appeared to be restricted to two specific regions of the FVIII molecule. Immunoblotting of purified FVIII and purified thrombin-degraded FVIII, followed by reaction with inhibitor plasma samples, monoclonal anti-human IgG3 and IgG4 antibodies, and radiolabeled affinity-purified rabbit anti-mouse IgG, revealed that inhibitor epitopes could be localized to the Mr 72,000 and Mr 44,000 thrombin fragments of FVIII. These two chains are located at the carboxyl terminus and near the amino terminus of the FVIII molecule, respectively. The pattern of reactivity of the inhibitor alloantibodies could be divided into three types: 10 reacted with the Mr 72,000 chain, 3 reacted with the Mr 44,000 chain, and 9 reacted with both of these chains. Among the 3 inhibitor autoantibodies, 1 of each type was found. Ten normal plasmas, as well as 14 plasmas from multitransfused individuals with severe hemophilia A and no inhibitor, were not reactive with the FVIII immunoblots. However, one multitransfused individual with severe hemophilia A and no detectable inhibitor revealed the presence of an antibody reactive with the middle section of the FVIII molecule. The existence of FVIII inhibitor epitopes on both the Mr 72,000 and Mr 44,000 chains raises the possibility that these epitopes might be further restricted to regions of homology between the two chains. These data suggest the possibility of designing inhibitor blocking polypeptides for use as therapeutic agents. 相似文献
36.
Mahoney CP Weinberger E Bryant C Ito M Jameson JL Ito M 《The Journal of clinical endocrinology and metabolism》2002,87(2):870-876
Postmortem examinations of the hypothalamus of patients with autosomal dominant neurohypophyseal diabetes insipidus (adNDI), which have been reported only on persons dying between the ages of 37-87 yr, reveal the presence of the arginine vasopressin (AVP)-producing parvocellular neurons but the absence of 95% of the expected AVP-producing magnocellular neurons. To determine whether the clinical course of adNDI is compatible with the hypothesis that the neuropathologic findings are attributable to a progressive loss of magnocellular neurons beginning in early life, we performed posterior pituitary magnetic resonance imaging and water deprivation tests, including plasma ACTH measurements, on 17 affected members of a kindred with the deltaE47 neurophysin mutation whose ages ranged from 3 months to 54 yr. Nine adult nonaffected members (ages, 20-56 yr) underwent these tests as controls. All six children undergoing magnetic resonance imaging demonstrated a posterior pituitary hyperintense signal (PPHS). Eight of nine affected adults showed an absent or barely visible PPHS, whereas eight of nine age-matched nonaffected adults produced a normal size PPHS. During water deprivation tests, infants concentrated their urine normally, and a 3-month-old infant produced a high plasma AVP level of 15.7 pmol/liter. By school age, affected children were no longer able to concentrate their urine or prevent hypernatremia. Affected adults became dehydrated; their median plasma AVP level was less than 1.0 pmol/liter, but their median fasting plasma ACTH was 2-fold greater than the level of nonaffected adults (10.0 vs. 5.0 pmol/liter; P = 0.008). These results suggest that adNDI is a progressive disease associated with chronic loss of the magnocellular neurons that supply AVP to the posterior pituitary but preservation of the parvocellular neurons that supply AVP and CRH to the median eminence and stimulate ACTH production during hypernatremia. 相似文献
37.
Study was made of 95 survivors of aortic valve replacement during the early years of this procedure (1964 to 1970). The average follow-up time was 50.2 months. Survival was not related to hemodynamic parameters, such as cardiac index or left ventricular pressure, and did not appear to be influenced by the type of preoperative valve lesion. A history of angina pectoris and a New York Heart Association Class IV grouping were associated with shorter survival. Associated coronary artery disease was a leading cause of death in those patients surviving less than 2 years and angina pectoris the leading cause of morbidity in the long-term survivors. Sudden death occurred in five patients. Once a patient survived 36 months after the operation, the prognosis was excellent. 相似文献
38.
PURPOSE: We determine the main outcome effects of a 12-month computer-mediated automated interactive voice response (IVR) intervention designed to assist family caregivers managing persons with disruptive behaviors related to Alzheimer's disease (AD). DESIGN AND METHODS: We conducted a randomized controlled study of 100 caregivers, 51 in the usual care control group and 49 in the technology intervention group, who received yearlong access to an IVR-mediated system. The system provided caregiver stress monitoring and counseling information, personal voice-mail linkage to AD experts, a voice-mail telephone support group, and a distraction call for care recipients. We conducted analyses by using a repeated measures approach for longitudinal data and an intention-to-treat analytic approach. Outcomes included the caregiver's appraisal of the bothersome nature of caregiving, anxiety, depression, and mastery at baseline, 6, 12, and 18 months. RESULTS: There was a significant intervention effect as hypothesized for participants with lower mastery at baseline on all three outcomes: bother (p =.04), anxiety (p =.01), and depression (p =.007). Additionally, wives exhibited a significant intervention effect in the reduction of the bothersome nature of caregiving (p =.02). IMPLICATIONS: Wives who exhibited low mastery and high anxiety benefited the most from the automated telecare intervention. Findings suggest that, to optimize outcome effects, similar interventions should be tailored to match the users' characteristics and preferences. 相似文献
39.
目的:探讨皮质醇增多症的临床表现和内分泌检查等辅助检查的意义.方法:从年龄、性别、病程及实验室检查等方面,观察22例不同原因所致皮质醇增多症患者不同的临床表现和测定实验室检查指标.结果:22例中诊断库欣病(增生型)14例[63.6%,其中13例(92.9%)得到MRI检查证实],肾上腺腺瘤6例[27.3%,均得到MRI检查证实(100%)],另有肾上腺结节样增生1例(4.5%),异位ACTH综合征1例(4.5%).临床表现:按出现的频率前4位依次为,库欣病:高血压(100%)、满月脸(92.9%)、向心性肥胖(85.7%)、多血质(85.7%),肾上腺腺瘤:高血压(100%)、满月脸(100%)、向心性肥胖(100%)、多血质(83.3%).实验室检查:小剂量地塞米松不能抑制:库欣病与肾上腺腺瘤均为100%.结论:根据高血压、满月脸、向心性肥胖,小剂量地塞米松抑制试验和MRI检查可诊断绝大多数皮质醇增多症. 相似文献
40.