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51.
ObjectivesTo scrutinize claims contained within Instagram posts related to six popular marketed orthodontic products.Materials and MethodsThree hundred publicly available Instagram posts were identified using the following Instagram hashtags: #carrieremotion, #damonbraces, #invisalign, #acceledent, #propelorthodontics, and #myobrace. Pilot coding was undertaken on a subset of claims (n = 50) and a coding guide was developed. The associated claims were categorized under 24 recognized themes and their accuracy assessed on a five-point scale.ResultsOf 1730 posts screened, 300 were included for analysis. The majority of posts were based on photographs (n = 244, 81.3%) with the remainder (n = 56, 18.7%) including videos. Half of the posts involved a picture of the product in isolation (n = 150, 50%), with clinical cases presented in a minority (n = 99, 33%). Overall, 472 claims were included with treatment duration being the most frequent theme (n = 125, 26.5%). In terms of accuracy, most of the claims were judged to be “false” (n = 283, 60%) with less than 2% considered “objectively true.”ConclusionsMost of the claims relating to six popular marketed orthodontic products concerned treatment duration. The vast majority of these claims were not supported by evidence and were judged to be false. Efforts should be made to promote the provision of accurate orthodontic information and to verify marketing claims on social media platforms.  相似文献   
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Preplaced aggregate concrete (PAC) is prepared in two steps, with the coarse aggregate being initially laid down in the formwork, after which a specialised grout is injected into it. To enhance the properties of concrete and to reduce the emission of CO2 produced during the production of cement, supplementary cementitious materials (SCMs) are used to partially substitute ordinary Portland cement (OPC). In this study, 100 mm × 200 mm (diameter x height) PAC cylinders were cast with 10 per cent of cement being substituted with silica fume; along with that, 1.5% dosage of Macro polypropylene fibres were also introduced into the coarse aggregate matrix. Compressive strength test, splitting tensile strength test, mass loss at 250 °C, and compressive strength at 250 °C were performed on the samples. PAC samples with 10% of cement replaced with Silica Fume (SPAC) were used as control samples. The primary objective of this study was to observe the effect of the addition of Polypropylene fibres to PAC having Silica fume as SCM (FRPAC). The aforementioned tests showed that FRPAC had a lower compressive strength than that of the control mix (SPAC). FRPAC had greater tensile strength than that of NPAC and SPAC. Mass loss at 250 °C was greater in SPAC compared to FRPAC. The compressive strength loss at 250 °C was significantly greater in FRPAC compared to SPAC. FRPAC exhibited a greater strain for the applied stress, and their stress-strain curve showed that FRPAC was more ductile than SPAC.  相似文献   
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Objective

To determine if the prevalence of diastolic dysfunction is increased in rheumatoid arthritis (RA) patients.

Methods

We conducted a time‐ and language‐restricted literature search to identify studies conducted to compare echocardiographic parameters in patients with RA and controls. The mean difference for echocardiographic variables of interest was calculated using a random‐effects model. A systematic review of the literature was performed.

Results

A total of 25 studies reporting on 5,836 subjects (1,614 with RA) were included. Results reflect mean differences, with positive values denoting higher values in RA patients. Patients with RA had larger mean left atrial dimension (mean difference 0.09 cm [95% confidence interval (95% CI) 0.01, 0.17]; P = 0.02), higher left ventricular mass index (mean difference 6.2 gm/m2 [95% CI 1.08, 11.33]; P = 0.02), higher mean systolic pulmonary artery pressure (mean difference 5.87 mm Hg [95% CI 4.36, 7.38]; P < 0.00001), prolonged isovolumetric relaxation time (mean difference 9.67 msec [95% CI 5.78, 13.56]; P < 0.00001), and higher transmitral A wave velocity (mean difference 0.13 meters/second [95% CI 0.07, 0.18]; P < 0.00001) compared to controls. A subanalysis of 2,183 subjects excluding 2 large unmatched studies showed the same results, with the exception that patients with RA had a lower mitral E/A ratio (mean difference ?0.17 [95% CI ?0.25, ?0.09]; P < 0.00001), suggestive of diastolic dysfunction. There were no differences in left ventricular ejection fraction (%), transmitral E wave velocity (meters/second), and mitral deceleration time (msec).

Conclusion

Patients with RA were more likely to have echocardiographic parameters of diastolic dysfunction, and have higher systolic pulmonary artery pressures and larger left atrial sizes.
  相似文献   
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J Clin Hypertens (Greenwich) Between 1995 and 2005, 196 adults with hypertrophic cardiomyopathy (HCM) were evaluated. Among these, 122 (62%, group 1) patients also had systemic hypertension. The clinical presentation, management, outcome, and echocardiographic findings of these patients were compared with 74 (38%, group 2) patients without systemic hypertension. Patients in group 1 were older at the time of HCM diagnosis and had a higher prevalence of diabetes (28% vs 9%; P=.02) and coronary artery disease (40% vs 25%; P=.03). In addition, echocardiography showed a significantly higher prevalence of systolic anterior motion of the anterior mitral valve in association with dynamic left ventricular outflow obstruction (52% vs 19%; P=.02) and mitral annular calcification (27% vs 13%; P=.03) in group 1 patients. Left ventricular wall thickness (17 mm vs 19 mm), end-diastolic diameter (42 mm vs 42 mm), resting outflow tract gradient >30 mm Hg (17% vs 16%), and ejection fraction (65% vs 64%) were similar in the two groups. HCM frequently coexists with systemic hypertension in the adult population. Presence of systemic hypertension in HCM patients is associated with older age and higher risk of diabetes, coronary artery disease, and noncardiac death.  相似文献   
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In late December 2019, a group of patients was observed with pneumonia‐like symptoms that were linked with a wet market in Wuhan, China. The patients were found to have a novel coronavirus genetically related to a bat coronavirus that was termed SARS‐CoV‐2. The virus gradually spread worldwide and was declared a pandemic by WHO. Scientists have started trials on potential preventive and treatment options. Currently, there is no specific approved treatment for SARS‐CoV‐2, and various clinical trials are underway to explore better treatments. Some previously approved antiviral and other drugs have shown some in vitro activity. Here we summarize the fight against this novel coronavirus with particular focus on the different treatment options and clinical trials exploring treatment as well as work done toward development of vaccines.  相似文献   
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IL-19, IL-20, IL-22, IL-24, IL-26, IL-28, and IL-29 are new members of the IL-10 interferon family. Monocytes are well-known sources of IL-19, IL-20, and IL-24. We demonstrated here that monocytes also expressed IL-29, and monocyte differentiation into macrophages (Mphi) or dendritic cells (DCs) strongly changed their production capacity of these cytokines. Maturation of DCs with bacterial stimuli induced high expression of IL-28/IL-29 and IL-20. Simulated T cell interaction and inflammatory cytokines induced IL-29 and IL-20 in maturing DCs, respectively. Compared with monocytes, DCs expressed only minimal IL-19 levels and no IL-24. The differentiation of monocytes into Mphi reduced their IL-19 and terminated their IL-20, IL-24, and IL-29 production capacity. Like monocytes, neither Mphi nor DCs expressed IL-22 or IL-26. The importance of maturing DCs as a source of IL-28/IL-29 was supported by the much higher mRNA levels of these mediators in maturing DCs compared with those in CMV-infected fibroblasts, and the presence of IL-28 in lymph nodes but not in liver of lipopolysaccharide-injected mice. IL-19, IL-20, IL-22, IL-24, and IL-26 do not seem to affect Mphi or DCs as deduced from the lack of corresponding receptor chains. The significance of IL-20 and IL-28/IL-29 coexpression in maturing DCs may lie in the broadly amplified innate immunity in neighboring tissue cells like keratinocytes. In fact, IL-20 induced the expression of antimicrobial proteins, whereas IL-28/IL-29 enhanced the expression of toll-like receptors (TLRs) and the response to TLR ligands. However, the strongest response to TLR2 and TLR3 activation showed keratinocytes in the simultaneous presence of IL-20 and IL-29.  相似文献   
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