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961.
To enhance the formability of magnesium alloys, inhibition of basal texture development by the particle-stimulated nucleation (PSN) effect has attracted significant interest. However, its contribution to texture development is not easily observed due to the separation of texture from the conventional deformation behavior. This study aims to separate the Ca texture from the deformation behavior of AZX611 alloy and quantify it using scanning electron microscopy with electron backscatter diffraction (SEM-EBSD). Since Ca in the AZ61 magnesium alloy precipitated as Al2Ca, the hot-rolled magnesium alloys AZ31, AZ61, and AZX611 were used. High temperature compression was conducted at 723 K, the strain rate 0.05/s and 0.005/s and the true strain up to −1.0. Dynamic recrystallization was observed in each specimen and the Ca-free alloys showed dislocation glide at high strain rates and solute drag at low strain rates. When the dislocation glide dominated, basal texture was strengthened. In contrast, solute drag caused non-basal texture development. Precipitation hardening caused AZ61 to have higher flow stress than those of the Ca-free alloys by the PSN effect; its texture was observed separately because the PSN grain growth around the precipitation and orientation was specific, similar to the one developed at the solute atom drag. 相似文献
962.
Yeon Soo Kim Jae Won Choi Ju-Kyeong Park Hyun Jung Kim 《Acta oto-laryngologica》2015,135(12):1311-1318
Conclusion: The results of the present investigation suggest that modification of HA could improve efficiency and durability in augmentation laryngoplasty. Objectives: Injection laryngoplasty (IL) is one of the most suitable options for treatment of glottic insufficiency, which is caused by vocal fold (VF) paralysis, atrophy, or scarring. Hyaluronic acid (HA) is a widely used material for VF injection. This study was intended to evaluate the durability and efficiency of HA of different particle sizes for VF augmentation. Methods: Three types of HA, Restylane®, monophasic low-viscosity, and unequal particle-sized middle-viscosity HA were injected into the left VF of three groups with eight rabbits each. Results: After 6 and 10 weeks, the injected site was evaluated endoscopically, histologically, radiologically, and functionally. None of the 24 rabbits showed any signs of respiratory distress. Computed tomography (CT) images and endoscopic evaluation revealed sufficient augmented volume of the injected VF in all treated groups 6 weeks after the injection. Histological data at week 10 showed that unequal particle-sized HA did not migrate from its original injection site, while other HAs migrated to the periphery of the arytenoid cartilage. Videokymographic analysis showed more favorable vibrations of unequal particle-sized HA injected VF mucosa 10 weeks post-injection, compared to the other treatment groups. 相似文献
963.
A previous animal study demonstrated that the administration of Omija extract and soybean mixture (OSM) improved glycemic control in the type 2 diabetes model. In this study, we conducted a 12-week, randomized, double-blinded, and placebo-controlled clinical trial to determine the effects of OSM in humans with hyperglycemia. Participants with fasting plasma concentrations of 100–140 mg/dL were enrolled (n = 80) and administered either OSM or placebo products for 12 weeks. The outcomes included measurements of efficacy (fasting plasma glucose (FPG), postprandial glucose (PPG), fasting plasma insulin (FPI), postprandial insulin (PPI), hemoglobin A1c (HbA1c), C-peptide, fructosamine, and lipid parameters) and safety at baseline and at 12 weeks. After the intervention, the OSM group showed significantly decreased levels of FPG, PPG (30, 60 min), PPI (60 min), insulin area under the curve (AUC), fructosamine, and low-density-lipoprotein (LDL) cholesterol compared to the placebo group. No clinically significant changes in any safety parameter were observed. Therefore, it is hypothesized that OSM supplementation is an effective and safe functional food supplement for humans with hyperglycemia. 相似文献
964.
965.
966.
Pulmonary atresia with intact ventricular septum (PAIVS) is a rare congenital cardiac anomaly that has been classified into
two types: one is a more frequent type having dysplasia of tricuspid valve (TV) with a small annulus, underdeveloped right
ventricle (RV) with a hypoplastic cavity and a hypertrophic wall; the other type has severe dysplasia of TV and dilatation
of RV, right atrium (RA), and right atrioventricular junction with thinning of the RV wall.
We performed a morphologic study on 11 autopsied hearts with PAIVS, giving particular emphasis to the variation of morphology
of the TV. We could classify these hearts into 3 groups according to the degree of right ventricular development. In the first
group of 7 cases (type I), the RVs were underdeveloped. Thick leaflets, restricted valve apparatus with short chordae, and
small annuli were characteristics of the TV. In the second group of 3 cases (type II), the RVs showed marked enlargement of
the cavity and thinning of the wall. The TV showed redundant, dysplastic, sail-like anterior leaflets, and the downward displacement
of septal leaflet and/or posterior leaflet, which are the findings frequently observed in Ebstein's malformation. The RVs
were dilated and with partially unguarded tricuspid orifice. The septal leaflet of the TV was dysplastic and, in two cases,
the septal leaflet showed chordal structure at the upper surface facing the RA, which is a peculiar finding that has not been
described in the literature. The remaining case was a heart with a moderately developed RV (type III). The TV showed mildly
dysplastic appearance and we classify this as a separate type, because we could expect the best surgical results in this type.
This type had optimal size of RV and the mildest degree of dysplasia of TV. In PAIVS, the morphology of TV correlates well
with the type of the right ventricular development. 相似文献
967.
Jeong Min Yang Su bin Lee Ye ji Kim Douk young Chon Jong Youn Moon Jae Hyun Kim 《Medicine》2022,101(32)
This empirical study identifies the negative aspects of private health insurance (PHI) by analyzing the association between subjective health conditions, 2 weeks of outpatient care, chronic diseases, and hospitalizations for 1 year. We used frequency analysis, χ2 testing, an analysis of variance, and logistic and multiple logistic regression models to analyze the association between PHI and subjective health conditions, outpatient care, chronic disease status, and hospitalization. The PHI group had good subjective health but had more outpatient care for 2 weeks. There were few chronic diseases in the private insurance group, and there was no significant difference in hospitalizations for 1 year. Hospitalization may occur when essential medical care is required, regardless of health insurance type. This study confirmed that as the PHI lowers the burden of personal medical expenses, the PHI can lead to an increase in the medical resource expenditures on the outpatient medical service and higher public health costs. The government should work to redefine the role of private and national health insurance. Also, the effectiveness of PHI should be reevaluated so that it does not lead to indiscriminate use of medical services by minimizing the burden of private insurance. 相似文献
968.
Hyun Jin Kang Hyo Jung Kim Ju Hee Han Chul Hwan Bang Tae-Yoon Kim 《ANNALS OF DERMATOLOGY》2022,34(4):297
Inflammatory acquired Blaschko-linear dermatoses (IABLD) are a continuous concept involving diseases such as lichen striatus, blaschkitis, and atopic dermatitis. However, atopic dermatitis that showed increase in severity along Blaschko lines is rarely reported on its own. Herein, we report a rare case of atopic dermatitis with secondary prurigo nodularis along Blaschko lines, which may be valuable in broadening the concept of IABLD. A 28-year-old male presented with multiple, pruritic, brownish nodules on the left lower extremity along Blaschko lines for 3 to 4 years. The patient had atopic dermatitis since childhood. Histopathologic findings revealed compact orthohyperkeratosis, hypergranulosis, spongiosis, and irregular acanthosis in the epidermis. Fibrosis with vertically arranged collagen fibers and perivascular lymphohistiocytic infiltration were shown in the upper dermis. We diagnosed the case as secondary prurigo nodularis along Blaschko lines, accompanied by the preceding atopic dermatitis. We hypothesized that the patient’s underlying atopic dermatitis increased in severity along Blaschko lines, and prurigo nodularis occurred due to frequent scratching. The lesions improved with topical methylprednisolone cream, oral antihistamines and intralesional triamcinolone injection. 相似文献
969.
970.
Kim A. Coutts Joanne Neille Nicole Louw 《The South African journal of communication disorders. Die Suid-Afrikaanse tydskrif vir Kommunikasieafwykings》2022,69(1)
BackgroundSouth Africa’s healthcare system has a multitude of pre-existing challenges prior to the onset of the coronavirus disease 2019 (COVID-19) pandemic, ranging from reduced number of staff, lack of resources and units being at overcapacity both in the adult and paediatric populations. The neonatal intensive care units (NICUs) require a team approach to ensure best practice with vulnerable infants, but little is known about how the onset of the COVID-19 pandemic and the resultant lockdown restrictions impacted the feeding practices within the NICU.ObjectivesThis study aimed to explore the impact that COVID-19 had on the feeding practices within the NICU settings in public hospitals in Gauteng.MethodsA qualitative design was employed with data collected in two NICUs in Gauteng. Data were collected in the form of observations and semi-structured interviews with healthcare workers (HCWs) in the NICU. Data were analysed using inductive thematic analysis.ResultsAlthough the sample size of participants was limited, social distancing proved to be a challenge resulting in mothers and healthcare workers being given restricted access. This had effects on the ability to provide adequate feeding practices and resulted in anxiety for the mothers and mental health challenges for the HCWs when feeding these at-risk infants. A limitation of this study was the use of only two sites.ConclusionCOVID-19 amplified the existing challenges in the NICU. A multidisciplinary and family-centred approach to address feeding challenges is required to offset the challenges resulting from the pandemic and subsequent lockdown. 相似文献