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Statement of problemWhich restorative material is best suited for treating the posterior molar region is unclear. As dentists presumably choose the most appropriate restoration, German dentists were asked how their own molars were treated.PurposeThe purpose of this survey study was to examine molar restorations and their durability in German dentists.Material and methodsIn the official journal of the Federal Dental Association, German dentists were asked to participate in an online survey that gathered demographic data and information on the type and durability of their molar restorations. To reduce selection bias, the data were weighted for region, sex, and age of the dentist.ResultsThe data set consisted of 1719 molars from 288 dentists. Restorations included gold inlays (25%), composite resin (24.3%), amalgam (11.8%), ceramic inlays (5.4%), glass ionomer cement or compomer (0.8%), gold crowns (21.8%), ceramic crowns (6.6%), and metal-ceramic crowns (4.3%). Notable differences were identified based on the sex, age, and region of the dentist. Women selected increased esthetic options, as did young dentists. Restorations made of gold, amalgam, and base metal had the highest longevity, at more than 20 yearsConclusionsAmong German dentists, restorations with metallic materials dominated in molars, with gold accounting for the largest share. In recent years, the proportion of tooth-colored restorations has increased, and in particular, young dentists use composite resin and ceramics.  相似文献   
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Background  There are specific issues regarding sexual orientation (SO) collection and analysis among transgender and nonbinary patients. A limitation to meaningful SO and gender identity (GI) data collection is their consideration as a fixed trait or demographic data point. Methods  A de-identified patient database from a single electronic health record (EHR) that allows for searching any discrete data point in the EHR was used to query demographic data (sex assigned at birth and current GI) for transgender individuals from January 2011 to March 2020 at a large urban tertiary care academic health center. Results  A cohort of transgender individuals were identified by using EHR data from a two-step demographic question. Almost half of male identified (46.70%, n  = 85) and female identified (47.51%, n  = 86) individuals had “heterosexual/straight” input for SO. Overall, male and female identified (i.e., binary) GI aggregate categories had similar SO responses. Assigned male at birth (AMAB) nonbinary individuals ( n  = 6) had “homosexual/gay” SO data input. Assigned female at birth (AFAB) nonbinary individuals ( n  = 56) had almost half “something else” SO data input (41.67%, n  = 15). Individuals with “choose not to disclose” for GI ( n  = 249) almost all had “choose not to disclose” SO data (96.27%, n  = 232). Conclusion  Current SO categories do not fully capture transgender individuals'' identities and experiences, and limit the clinical and epidemiological utility of collecting this data in the current form. Anatomical assumptions based on SO should be seen as a potential shortcoming in over-reliance on SO as an indicator of screening needs and risk factors.  相似文献   
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INTRODUCTION: Recent studies in adult populations have revealed seasonal variation in the frequency of acute cardiovascular events, including life-threatening arrhythmias, demonstrating increased events during winter and early spring. Trends in the time of day that arrhythmias occur also were noted. We sought to establish whether pediatric and young adult congenital heart disease implantable cardioverter defibrillator (ICD) recipients have circadian or seasonal variability in shock frequency, similar to adult populations. METHODS AND RESULTS: Data from ICD patients at six pediatric centers in North America were analyzed to assess the timing of life-threatening arrhythmias. The populations consisted of children and adults with congenital heart disease and ICDs placed for malignant arrhythmias. Data were considered in 46 patients who received appropriate therapy (total 139 episodes) for ventricular tachycardia or ventricular fibrillation. Multiple variables were analyzed, including time of day, day of week, and month of year. In contrast to previously studied adult patients, fewer events occurred in the early morning (7.5%), with the most therapies occurring between 6 P.M. and midnight (35%). An increased frequency of therapies was observed in the fall and winter (September-January), representing 60% of all appropriate shocks. Unlike adult populations, Mondays did not have an increased frequency of malignant arrhythmias. CONCLUSION: Pediatric and adult congenital heart disease populations have moderate seasonal and 24-hour variation in ICD event rate, with some distinctly different peaks than those seen in typical adult ICD populations. These findings suggest circadian variation in arrhythmia vulnerability that may differ from conventional occupational, physical, or emotional stressors. (J Cardiovasc Electrophysiol, Vol. 13, pp.  相似文献   
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We report an unanticipated medication effect resulting in near‐complete wound healing in a patient after beginning tadalafil therapy of 20 mg thrice daily. This patient was treated for 50 years with state‐of‐the art acute and then chronic wound interventions after a traumatic farm machinery accident which resulted in a devascularised foot wound. This infection was both life‐ and limb‐threatening. The patient had undergone multiple vascular and plastic surgeries and antimicrobial therapies in addition to hospitalisations for sepsis. Limb amputation was being considered, when his urologist placed him on daily phosphodiesterase‐5 inhibitor therapy, prior to unrelated urologic surgery. Remarkably, his foot wound underwent near‐complete resolution and has been stable for 2 years.  相似文献   
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Previous work has suggested that Trypanosoma cruzi diphosphohydrolase 1 (TcNTPDase-1) may be involved in the infection of mammalian cells and serve as a potential target for rational drug design. In this work, we produced recombinant TcNTPDase-1 and evaluated its nucleotidase activity, cellular localization and role in parasite adhesion to mammalian host cells. TcNTPDase-1 was able to utilize a broad range of triphosphate and diphosphate nucleosides. The enzyme's Km for ATP (0.096 mM) suggested a capability to influence the host's ATP-dependent purinergic signaling. The use of specific polyclonal antibodies allowed us to confirm the presence of TcNTPDase-1 at the surface of parasites by confocal and electron microscopy. In addition, electron microscopy revealed that TcNTPDase-1 was also found in the flagellum, flagellum insertion region, kinetoplast, nucleus and intracellular vesicles. The presence of this enzyme in the flagellum insertion region and vesicles suggests that it may have a role in nutrient acquisition, and the widespread distribution of TcNTPDase-1 within the parasite suggests that it may be involved in other biological process. Adhesion assays using anti-TcNTPDase-1 polyclonal antibodies as a blocker or purified recombinant TcNTPDase-1 as a competitor revealed that the enzyme has a role in parasite–host cell adhesion. These data open new frontiers to future studies on this specific parasite–host interaction and other unknown functions of TcNTPDase-1 related to its ubiquitous localization.  相似文献   
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The concept of mimicking structural colour in nature as an alternative to traditional textile coloration techniques would reduce dependency on dyes, pigments and vast quantities of water in the textile supply chain. Structural colours originate from the physical interaction of light with nanoscale structures. This is exhibited in the bodies and wings of certain species of butterfly, beetles and plants. The angular optical effects of the Chrysina gloriosa beetle result from the periodicity due to the cholesteric liquid crystal (CLC) structure adopted by the cells in their exoskeleton. The optical properties of CLCs makes promising applications for optical sensors and anti-counterfeit materials. Application using inkjet printing technology enables designs to be tuned to meet product requirements, and with a hydrophobic treatment challenges associated with a rough surface such as textiles are overcome. Here we report inkjet printing CLC solutions onto hydrophobic pre-treated textiles. CIE L*a*b* values demonstrate the resultant colourful films display a greater degree of colour compared to those on untreated textiles.

The concept of mimicking structural colour in nature as an alternative to traditional textile coloration techniques would reduce dependency on dyes, pigments and vast quantities of water in the textile supply chain.  相似文献   
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