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1.
OBJECTIVES: The aim of the study was to investigate the relationship between microstructure, acoustic and mechanical properties of hardened dental cement samples, prepared with different powder/water ratios. METHODS: Glass-ionomer dental cement samples, prepared with a standard amount of cement powder and different amounts of water have been examined after being hardened. Surface microstructure and ultrasound, longitudinal and shear velocities were obtained with a scanning acoustic microscope. Conditional effective elastic modulus and Poisson's ratio have been calculated using longitudinal and shear sound velocity values. Then on the same samples elastic modulus and microhardness have been determined by standard tests. Additional samples have been used to determine compressive strength. RESULTS: Density; conditionally instantaneous elastic modulus; high-elasticity modulus and compression strength of the samples decrease when large amounts of water were used for their preparation. At the same time porosity and microhardness of the cement matrix increase. Acoustic parameters and parameters of elasticity, calculated on the basis of sound velocity, demonstrated changes, similar to those obtained in standard mechanical tests. SIGNIFICANCE: The established relation between microstructure, acoustic and mechanical parameters demonstrated a high capacity of acoustic microscopy application for non-destructive characterization of dental materials. A particular advantage of the acoustic microscopy is the opportunity to evaluate microstructure and mechanical properties on the same sample.  相似文献   
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The teacher-led implementation of healthy eating programs in schools is cost-effective and potentially impactful. Teacher acceptability is important for uptake; however, process evaluations are scarce. This study evaluated the effect of two intensities of teacher training on the evaluation of a vegetable education program for Australian primary schools by teachers. The teachers (n = 65) who implemented the program as part of a cluster RCT (25 schools in two states, New South Wales and South Australia) received either low- (provision with materials and online training) or high (additional face-to-face (F2F) training)-intensity training prior to implementing a 5-week vegetable education program. They evaluated the acceptability of a digital training module and program by indicating the level of agreement with 15 and 18 statements, respectively, using 5-point Likert scales. The average item scores ranged from 3.0 to 4.2. All but one item, including student engagement, alignment to the curriculum and intent for reuse of the program, had a rounded average or median score of 4. The level of training intensity did not impact the teacher acceptability ratings. In conclusion, the teacher acceptability was good, and additional F2F training does not add value above the solely digital training of the teachers.  相似文献   
4.
Aneurysmal cysts of the mandible and maxilla are rare conditions, though not exceptional, which are seen in particular in the child and adolescent. A part from facial asymmetry and tumefaction, it is rare to find other clinical manifestations. No neurological signs were seen in the present study. An aneurysmal cyst gives a radiological appearance of non-characteristic lysis compatible with a large range of diagnoses. Histological study permits early diagnosis but must always involve the whole specimen with careful examination to detect any other associated lesion. The pathogenesis of the condition remains obscure and, at the extreme, it may be questioned whether the aneurysmal cyst is a separate entity or a particular form of chronic osteopathy.  相似文献   
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Left ventricular hypertrophy (LVH) is a common finding in hypertensive autosomal dominant polycystic kidney disease (ADPKD) patients. There are few studies on the influence of blood pressure (BP) and nonhemodynamic factors on LVH in these patients. The aim of this study was to evaluate the relationship between BP, humoral and neurohormonal factors and left ventricular mass (LVM) in hypertensive ADPKD patients. In 20 hypertensive ADPKD patients, ambulatory BP was monitored for 24 h, left ventricular dimensions were estimated by echocardiography, and plasma renin activity (PRA), plasma noradrenaline (NA), angiotensin II (Ang II), aldosterone, atrial natriuretic peptide (ANP) and insulin-like growth factor I (IGF-I) were also determined. Twenty age- and sex-matched essential hypertensive subjects served as controls. Ambulatory BP and LVM index were similar in the two groups, although male ADPKD patients had higher LVM indices than their matched controls. Eight ADPKD patients (40%) and 6 essential hypertensives (30%) showed LVH. PRA, Ang II, aldosterone, ANP and IGF-I levels were similar in the two groups, but plasma NA levels were higher in ADPKD patients than in controls (281 +/- 158 vs. 160 +/- 62 pg/ml, p = 0.004). ADPKD patients with LVH did not differ from those without LVH with regard to humoral and neurohormonal parameters, but had higher ambulatory BP levels. In ADPKD patients, correlation analysis revealed a significant association between LVM index and 24-hour systolic and diastolic BP, but not with any of the hormonal factors evaluated. On multiple regression analysis, 24-hour diastolic BP was the only independent variable linked to LVM index. In conclusion, ambulatory BP is one of the most important determinants of LVM in hypertensive ADPKD patients. Further studies are warranted to elucidate the role of nonhemodynamic factors in the pathogenesis of LVH in this population.  相似文献   
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Chronic cannabis use can be associated with uncontrollable vomiting and abdominal pain. Diagnostic criteria for cannabinoid hyperemesis syndrome (CHS) were defined in 2012 by Simonetto et al. The objectives of this study were to describe the prevalence of CHS, the patients' epidemiological characteristics, and to show the difficulties encountered in caring for these patients in emergency departments, the extent of health care and an unsuitable follow‐up in general practices. A prospective cohort of patients with CHS was recruited among a target population of patients leaving the adult emergency services of the Marseille hospitals Nord and La Timone between October 2017 and July 2018, with abdominal pain syndrome of unidentified etiology. Inclusion criteria for the CHS cohort were chronic cannabis use associated with nausea and vomiting. There were 48 patients included in the CHS cohort who took cannabis daily, in a target population of 2 848 patients (i.e. 1.6%). A hot shower was the most effective symptomatic treatment in 54.2% of cases. Patients suffering from CHS spent significantly more hours in emergency departments (11 vs. 6.5), and, on average, visits were more frequent (4.9 vs. 3). 20.3% of them were hospitalized to continue pain medication. Once out of hospital, follow‐up was limited, and weaning off cannabis, the only etiological treatment, was difficult to set up. Informing patients about CHS is essential, and a hot shower could be systematically proposed, thus limiting an unnecessary extent of health care. CHS is genuine, medical staff should be made aware of it in occupational training, and it should be seriously considered in health policies.  相似文献   
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Autophagy is the process by which superfluous or damaged macromolecules or organelles are degraded by the lysosome. Pharmacologic and genetic evidence indicates that autophagy plays pleiotropic functions in cellular homeostasis, development, survival, and differentiation. The differentiation of human blood monocytes into macrophages is a caspase-dependent process when triggered ex vivo by colony stimulating factor-1. We show here, using pharmacologic inhibitors, siRNA approaches, and Atg7-/- mice, that autophagy initiated by ULK1 is required for proper colony stimulating factor-1-driven differentiation of human and murine monocytes. We also unravel a role for autophagy in macrophage acquisition of phagocytic functions. Collectively, these findings highlight an unexpected and essential role of autophagy during monocyte differentiation and acquisition of macrophage functions.  相似文献   
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Background

Dislocation and leg length discrepancy are major complications following total hip arthroplasty (THA). Many surgical approaches for THA have been described, but none suggest a capsular incision that assures good exposure while maintaining adequate capsule integrity in closure.

Purposes

Modified anterolateral approach for stable hip (MAASH) is a modification of the classical Hardinge approach, but specifically preserves the anterior iliofemoral lateral ligament and pubofemoral ligament excising the “weak area” of the capsule, in the so called “internervous safe zone” and introducing the “box concept” for the anterior approach to the hip. This is the main difference of the MAASH approach. This technique can be used as a standard for all THA standard models, but we introduce new devices to make it easier.

Methods

From November 2007 to May 2012, data were collected for this observational retrospective consecutive case study. We report the results of 100 THA cases corresponding to the development curve of this new concept in THA technique.

Results

MAASH technique offers to hip surgeons, a reliable and reproducible THA anterolateral technique assuring accurate reconstruction of leg length and a low rate of dislocation. Only one dislocation and six major complications are reported, but most of them occurred at the early stages of technique development.

Conclusion

MAASH technique proposes a novel concept on working with the anterior capsule of the hip for the anterolateral approach in total hip arthroplasty, as well as for hemiarthroplasty in the elderly population with high dislocation risk factors. MAASH offers maximal stability and the ability to restore leg length accurately.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-013-9332-1) contains supplementary material, which is available to authorized users.  相似文献   
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