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151.
BackgroundWhile anti-vaccine messages on social media have been studied for content, reach, and effectiveness, less is known about those who create and promote the messages. Online influencers, or ‘everyday people who are influential within their online social networks’, are viewed as trusted voices who are often making similar life decisions as their followers. Therefore, their experiences with and perspectives on health issues can be persuasive.MethodsWe collaborated with a formal network of online influencers to interview, using a semi-structured interview guide, vaccine hesitant influencer mothers about their views on vaccination; their process for developing health-related social media content; their motivation to promote anti-vaccine messages; and their opinions on current vaccination messaging. Prescreening ensured a diverse sample by race/ethnicity, age, education, number of children, and geographic residence. Interviews occurred by telephone, were audio recorded, and transcribed. Themes were generated independently by two coders using a deductive coding approach.ResultsWe interviewed 15 online influencer mothers from across the U.S. (average age 39 years old; all married; 13 Caucasian, 1 African American, 1 Hispanic). In some capacity, 5 of the 15 wrote about vaccination on their blog. Those who chose not to post anti-vaccine content did so for fear of alienating followers or having their platform be the site of combative discourse among readers. When researching their social media posts, the influencers did not trust mainstream sources of health information and relied on alternative sources and search engines.Implications: This exploratory study interviewed influential mothers who have the ability to spread anti-vaccine messages on social media. While most do not contribute to the anti-vaccine sentiment, understanding the motivation and practices of those that do assists the public health community in better understanding the online vaccination communication environment, leading to more effective messages to counterbalance anti-vaccine content on social media.  相似文献   
152.
Journal of Prevention - Social and Emotional Learning (SEL) programs seek to enhance social and emotional competencies in children, including self-awareness, self-management, social awareness,...  相似文献   
153.
RNA interference (RNAi) is a flexible gene silencing mechanism that responds to double-stranded RNA by suppressing homologous genes. Here, we report the characterization of RNAi effector complexes (RISCs) that contain small interfering RNAs and microRNAs (miRNAs). We identify two putative RNA-binding proteins, the Drosophila homolog of the fragile X mental retardation protein (FMRP), dFXR, and VIG (Vasa intronic gene), through their association with RISC. FMRP, the product of the human fragile X locus, regulates the expression of numerous mRNAs via an unknown mechanism. The possibility that dFXR, and potentially FMRP, use, at least in part, an RNAi-related mechanism for target recognition suggests a potentially important link between RNAi and human disease.  相似文献   
154.
Exposing individuals to an isolated component (a prime) of a prior event alleviates its forgetting. Two experiments with 120 human infants between 3 and 18 months of age determined the minimum duration of a prime that can reactivate a forgotten memory and how long the reactivated memory persists. Infants learned an operant task, forgot it, were exposed to the prime, and later were tested for renewed retention. In Experiment 1, the minimum duration of an effective prime decreased logarithmically with age, but was always longer than the duration of a mere glance. In Experiment 2, the reactivated memory was forgotten twice as fast after a minimum-duration prime as after a full-length one, irrespective of priming delay and infant age. These data reveal that the minimum effective prime duration psychophysically equates the accessibility of forgotten memories. We conclude that priming is perceptually based with effects that are organized on a ratio (log) scale.  相似文献   
155.
Summary In rats respiratory tract infections due to Sendai virus and coronavirus usually are transient, but they can have long-lasting consequences when accompanied by Mycoplasma pulmonis infections. Morphological alterations in the tracheal epithelium and a potentiation of the inflammatory response evoked by sensory nerve stimulation (neurogenic inflammation) are evident nine weeks after the infections begin, but the extent to which these changes are present at earlier times is not known. In the present study we characterized these abnormalities in the epithelium and determined the extent to which they are present 3 and 6 weeks after the infections begin. We also determined the magnitude of the potentiation of neurogenic inflammation at these times, whether the potentiation can be reversed by glucocorticoids, and whether a proliferation of blood vessels contributes to the abnormally large amount of plasma extravasation associated with this potentiation. To this end, we studied Long-Evans rats that acquired these viral and mycoplasmal infections from other rats. We found that the tracheal epithelium of the infected rats had ten times as many Alcian blue-PAS positive mucous cells as did that of pathogen-free rats; but it contained none of the serous cells typical of pathogen-free rats, so the total number of secretory cells was not increased. In addition, the epithelium of the infected rats had three times the number of ciliated cells and had only a third of the number of globule leukocytes. In response to an injection of capsaicin (150 g/kg i.v.), the tracheas of the infected rats developed an abnormally large amount of extravasation of two tracers Evans blue dye and Monastral blue pigment, and had an abnormally large number of Monastral blue-labeled venules, particularly in regions of mucosa overlying the cartilaginous rings. This abnormally large amount of extravasation was blocked by dexamethasone (1 mg/day i.p. for 5 days). We conclude that M. pulmonis infections, exacerbated at the outset by viral infections, result within three weeks in the transformation of epithelial serous cells into mucous cells, the proliferation of ciliated cells, and the depletion of globule leukocytes. They also cause a proliferation of mediator-sensitive blood vessels in the airway mucosa, which is likely to contribute to the potentiation of neurogenic inflammation that accompanies these infections.Funded in part by National Institutes of Health Pulmonary Program Project Grant HL-24136 from the US Public Health Service. Dr. Huang is the recepient of an award from the National Science Council of the Republic of China  相似文献   
156.
157.
Retrospective data showed that when we administered ledipasvir/sofosbuvir (LDV/SOF) to patients with hepatitis B and C coinfection, there was a modest reduction in hepatitis B surface antigen (HBsAg). Therefore, we hypothesize that similar HBsAg reduction can be seen in hepatitis B virus (HBV) monoinfected subjects. Primary and secondary efficacy endpoints are the decline in HBsAg and HBV DNA at Week 12 from baseline, respectively. We conducted an open-label Phase 2 pilot study to evaluate the safety, tolerability, and antiviral activity of LDV and/or SOF for HBV. Eligible subjects were either suppressed on antivirals (Group B) or inactive chronic HBV (Group A, C, D). Group A and B received LDV/SOF. Group C and D received SOF 400 mg and LDV 90 mg, respectively. All subjects completed the study, and all related adverse events (AEs) were mild. No discontinuations due to AEs or hepatitis flare occurred. At Week 12, HBsAg decline (log10 IU/ml) was similar between Group A (0.399) and B (0.400), less in Group C (0.207), and none in Group D, and there was HBV DNA decline in the inactive chronic HBV groups. LDV and SOF are safe and well tolerated when given to chronic hepatitis B subjects and have modest antiviral activity, particularly when given in combination.  相似文献   
158.
Journal of Digital Imaging - Measurement of angles on foot radiographs is an important step in the evaluation of malalignment. The objective is to develop a CNN model to measure angles on...  相似文献   
159.
160.
Summary Cell motility, a primary component of tumor cell invasion, is a continuum of sequential events in which the cell extends pseudopodia, forms nascent attachments, assembles and contracts the cytoskeleton, and finally, as it translocates forward, disengages distal adhesions. What triggers cells to move? Substratum contact mediated by integrin adhesion receptors is important, but other signals such as chemokinetic factors appear to be required for continued crawling. It is now apparent that integrins do not simply bind cells to matrix in a Velcrolike fashion, but also are potent signaling molecules. Initial engagement of integrins induces their condensation into focal contacts, forming anchors to the extracellular matrix and discrete signal-transducing complexes on the cytoplasmic surface. A number of growth factors, through either autocrine or paracrine pathways, can activate the cellular machinery that mobilizes the cell. Thus, these two classes of receptors - the integrin receptors that bind specific extracellular adhesion molecules, and growth factor receptors that bind their respective ligands - can regulate cell locomotion. Not surprisingly, there is cross-talk between integrin and growth factor receptors that occurs through their common intracellular signaling pathways. In this way, each receptor type can either amplify or attenuate the other's signal and downstream response. An example of growth factor-induced motility is the epithelial-mesenchymal transition induced by hepatocyte growth factor/scatter factor (HGF/SF). When bound to its receptor, the c-met proto-oncogene product, HGF/SF induces a phenotypic conversion that appears to be an important aspect of tumor progression in malignant carcinomas. The motogenic response produced by HGF/SF in carcinoma cells occurs in discrete steps in which integrins and focal adhesion kinase (p125FAK) are first recruited to focal contacts. This is rapidly followed by cell spreading, disruption of focal adhesions and cell-cell contacts, and, finally, cell crawling. The precise mechanism by which growth factors such as HGF/SF and its receptor induce this motogenic response and modulate integrin function has not been clearly defined but appears to involve several signaling pathways. Understanding the process by which growth factor and integrin receptors interact and regulate motility may suggest novel targets for therapeutic intervention.  相似文献   
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