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11.
12.
Peet J. van der Vyver Farzana Paleker Martin Vorster Francois A. de Wet 《Journal of endodontics》2019,45(1):62-67
Introduction
The aim of this study was to evaluate the root canal shaping effect of instruments manufactured from nickel titanium, M-Wire, and Gold wire with different glide path preparation techniques.Methods
One hundred thirty-five mesiobuccal canals of extracted human maxillary molars were randomly divided into 3 equal groups (N = 45) for glide path preparation with K-files (KF) (Dentsply Sirona, Ballaigues, Switzerland), One G (OG) files (Micro-Mega, Besançon, France), and ProGlider (PG) files (Dentsply Sirona). Specimens of each glide path group were further divided equally into 3 groups for instrumentation with ProTaper Next (PTN, Dentsply Sirona), One Shape (OS, Micro-Mega), and WaveOne Gold (WOG, Dentsply Sirona) systems (n = 15). Micro–computed tomographic imaging was used to scan teeth before instrumentation and after shaping to compare centering ratio and canal transportation values at the apical, midroot, and coronal levels and the overall changes in canal volume. Data sets were statistically analyzed (analysis of variance and Kruskal-Wallis H tests).Results
The centering ratios for all groups were statistically similar at all levels. Apical canal transportation was significantly high for K/OS and K/PTN (P = .003). Midroot canal transportation was significantly high for K/PTN, K/OS, and OG/OS (P = .0003). Coronal canal transportation was significantly high for K/PTN and K/OS (P = .011). The highest change in canal volume was observed with all PTN groups and the lowest with PG/WOG (P = .06).Conclusions
WOG manufactured from Gold wire combined with PG showed better root canal shaping ability and removed less dentin from the canal walls. The nickel-titanium (OS) and M-Wire (PTN) instruments used in combination with KF significantly transported more canals. PTN removed the most dentin from the canal walls regardless of the GPP technique. 相似文献13.
Michelle Y L Tang Patrick H Y Chung Hau Y Chan Paul K H Tam Kenneth KY Wong 《Journal of pediatric surgery》2019,54(2):255-257
Objective
Helicobacter pylori infection is common among Asians. However, evidence in the recent years has demonstrated a decrease in the prevalence of H. pylori infection among children and adults worldwide. Our aim was to update its prevalence in symptomatic children in our locality in the recent 12?years and compared to the results of our previous review published in 2005.Methods
A retrospective review was carried out between 2005 and 2017. All children who presented with dyspepsia or gastrointestinal bleeding and underwent oesophagogastroduodenoscopy with antral biopsy taken were included. Patient demographics, endoscopic, or histological diagnosis and the H. pylori status were recorded.Main Results
A total of 602 patients were included. There was a statistically significant decreasing trend of H. pylori infection rate between 2005 and 2017 (p?=?0.003). The overall infection rate from this study was 12.8%, compared to 25.6% from our previous review. Overall failure of eradication with first-line antibiotic therapy has increased to 29.3% from 10% in our previous review.Conclusion
There was a decrease in the prevalence of H. pylori infection among symptomatic children for the recent 12?years, comparing to our previous data from 2005. We hypothesize that the reduction in prevalence of H. pylori infection among adults and the decrease in the practice of sharing chopsticks during meals have led to a decrease in transmission of the bacteria among family members in Hong Kong. However, the failure of eradication with first line treatment was higher, possibly due to the increase in antibiotics usage and resistance.Level of Evidence
III 相似文献14.
Inna Y. Gong Nigel S. Tan Sammy H. Ali Gerald Lebovic Muhammad Mamdani Shaun G. Goodman Dennis T. Ko Andreas Laupacis Andrew T. Yan 《The Canadian journal of cardiology》2019,35(5):653-660
Background
Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.Methods
We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.Results
In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).Conclusions
Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials. 相似文献15.
D. Medenwald A. Kluttig M.E. Lacruz J. Schumann 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):152-158
Background and Aims
Diet is known to play a decisive role in the development of coronary heart disease (CHD). One factor believed to decrease lifetime risk of CHD is the consumption of omega-3 fatty acids. Yet, conclusive evidence regarding the potential cardioprotective effects of fatty acids is far from being reached. The present study aimed to provide further evidence on the association of serum fatty acid profiles with CHD risk.Methods and Results
The CARdio-vascular Disease, Living and Ageing in Halle study (CARLA study) is an observational cohort study comprising an older adult's general population with a high level of cardiovascular risk factors. In a matched case–control design the serum fatty acid concentrations of 73 subjects with an incident fatal or nonfatal CHD event were compared to 146 controls matched for sex and age. Our data show that the participants of the CARLA study are underserved in unsaturated fatty acids with respect to current dietary recommendations. In addition, the ratio of omega-6 to omega-3 fatty acids was determined to be 8:1 which underlines the consumption of a Western-style diet enriched in omega-6 fatty acids. There were no significant differences in fatty acid patterns between cases and controls. Thus, no clear association of particular serum fatty acid levels with cardiovascular risk was found.Conclusion
Our results support the conclusion that in populations with a homogenous low level of omega-3 polyunsaturated fatty acids consumption, serum fatty acid levels are not associated with CHD risk. 相似文献16.
Perinatal hypoxic-ischemic encephalopathy is a leading cause of neonatal death and disability.Therapeutic hypothermia significantly reduces death and major disability associated with hypoxic-ischemic encephalopathy;however,many infants still experience lifelong disabilities to movement,sensation and cognition.Clinical guidelines,based on strong clinical and preclinical evidence,recommend therapeutic hypothermia should be started within 6 hours of birth and continued for a period of 72 hours,with a target brain temperature of 33.5 ±0.5℃ for infants with moderate to severe hypoxic-ischemic encephalopathy.The clinical guidelines also recommend that infants be re warmed at a rate of 0.5℃ per hour,but this is not based on strong evidence.There are no randomized controlled trials investigating the optimal rate of rewarming after therapeutic hypothermia for infants with hypoxic-ischemic encephalopathy.Preclinical studies of rewarming are conflicting and results were confounded by treatment with sub-optimal durations of hypothermia.In this review,we evaluate the evidence for the optimal start time,duration and depth of hypothermia,and whether the rate of rewarming after treatment affects brain injury and neurological outcomes. 相似文献
17.
J. Shin J. Choi K.J. Kim 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):144-151
Background and aim
The associations of long-term exposure to particulate matter <10 μm in size (PM10), nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), and ozone (O3) with cardiometabolic diseases (CMD) remain uncertain in the Korean population. Therefore, we sought to examine the associations between PM10, NO2, CO, SO2, and O3 and CMD using data collected from the Korean Community Health Survey.Methods and results
We selected 100,867 adults aged 19 years or older who had lived in the same domicile for ≥10 years and surveyed them to collect data on socioeconomic characteristics; health-related behaviors; obesity; and physician-diagnosed CMD history, including hypertension, diabetes mellitus, dyslipidemia, stroke, myocardial infarction, and ischemic heart disease. We calculated interquartile ranges for PM10, NO2, CO, SO2, and O3 from the 10 year average concentrations (2003–2012). Hypertension, diabetes mellitus, and dyslipidemia were positively associated with PM10, NO2, CO, SO2, and O3 after adjusting for confounding factors. Obesity was positively associated with PM10, NO2, SO2, and O3. On the other hand, we found no associations between stroke, myocardial infarction, and ischemic heart disease and exposure to PM10, NO2, CO, SO2, and O3 in these subjects. In subjects aged ≥65 years, the risk of dyslipidemia was markedly increased under exposure to NO2 and CO compared to subjects aged <65 years. The risk of obesity was also significantly increased under exposure to PM10 and NO2. However, sex differences in these associations were not found.Conclusion
Long-term exposure to PM10, NO2, CO, SO2, and O3 may be a risk factor of CMD in Korean adults. 相似文献18.
Julia H. Vermylen Gordon J. Wood Elaine R. Cohen Jeffrey H. Barsuk William C. McGaghie Diane B. Wayne 《Journal of pain and symptom management》2019,57(3):682-687
Introduction
Physician communication impacts patient outcomes. However, communication skills, especially around difficult conversations, remain suboptimal, and there is no clear way to determine the validity of entrustment decisions. The aims of this study were to 1) describe the development of a simulation-based mastery learning (SBML) curriculum for breaking bad news (BBN) conversation skills and 2) set a defensible minimum passing standard (MPS) to ensure uniform skill acquisition among learners.Innovation
An SBML BBN curriculum was developed for fourth-year medical students. An assessment tool was created to evaluate the acquisition of skills involved in a BBN conversation. Pilot testing was completed to confirm improvement in skill acquisition and set the MPS.Outcomes
A BBN assessment tool containing a 15-item checklist and six scaled items was developed. Students' checklist performance improved significantly at post-test compared to baseline (mean 65.33%, SD = 12.09% vs mean 88.67%, SD = 9.45%, P < 0.001). Students were also significantly more likely to have at least a score of 4 (on a five-point scale) for the six scaled questions at post-test. The MPS was set at 80%, requiring a score of 12 items on the checklist and at least 4 of 5 for each scaled item. Using the MPS, 30% of students would require additional training after post-testing.Comments
We developed a SBML curriculum with a comprehensive assessment of BBN skills and a defensible competency standard. Future efforts will expand the mastery model to larger cohorts and assess the impact of rigorous education on patient care outcomes. 相似文献19.
Christopher N. Cooley Tyler J. Beranek Matthew A. Warpinski Robert Alexander Amanda O. Esquivel 《The American journal of emergency medicine》2019,37(2):199-203
Introduction
In the United States there has been a large increase in participation in lacrosse for both males and females. The purpose of this study was to analyze the number of head injuries, injury rates (calculated using the reported number of participants) and types of head injuries that are seen in emergency departments in the United States.Methods
We compared injuries between male and female lacrosse participants. This was a retrospective study using a publicly available database produced by the US Consumer Product Safety Commission and information about lacrosse participation from US Lacrosse.Results
A linear regression was performed and showed a positive correlation between number of head injuries to males and time from 2002 to 2010 (R2?=?0.823; p?=?0.001). While the number of injuries to the head in female lacrosse participants was not significant. There was a negative correlation between the number of head injuries to males from 2010 to 2016 (R2?=?0.800; p?=?0.007), but again, there was no significance for female injury count (R2?=?0.417; p?=?0.117). Other significant differences between head injuries in males and females included the mechanism of injury and the type of injury recorded.Conclusion
The most recent data from 2010 to 2016, suggest that both males and females have had a decrease in injury rate. However the total number of female head injuries is not significantly decreasing and as the sport continues to grow there will likely be more total head injuries and visits to the emergency department. 相似文献20.
Sophia A. Traven Russell A. Reeves Molly G. Sekar Harris S. Slone Zeke J. Walton 《The Journal of arthroplasty》2019,34(1):140-144