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81.
Silicon-based anodes can increase the energy density of Li-ion batteries (LIBs) owing to their large weights and volumetric capacities. However, repeated charging and discharging can rapidly deteriorate the electrochemical properties because of a large volume change in the electrode. In this study, a commercial Fe-Si powder was coated with Al2O3 layers of different thicknesses via atomic layer deposition (ALD) to prevent the volume expansion of Si and suppress the formation of crack-induced solid electrolyte interfaces. The Al2O3 content was controlled by adjusting the trimethyl aluminum exposure time, and higher Al2O3 contents significantly improved the electrochemical properties. In 300 cycles, the capacity retention rate of a pouch full-cell containing the fabricated anodes increased from 69.8% to 72.3% and 79.1% depending on the Al2O3 content. The powder characterization and coin and pouch cell cycle evaluation results confirmed the formation of an Al2O3 layer on the powder surface. Furthermore, the expansion rate observed during the charging/discharging of the pouch cell indicated that the deposited layer suppressed the powder expansion and improved the cell stability. Thus, the performance of an LIB containing Si-alloy anodes can be improved by coating an ALD-synthesized protective Al2O3 layer. 相似文献
82.
83.
Taehyeok Hwang Hyo Jung Lee Woo Sung Park Dong-Min Kang Mi-Jeong Ahn Hyonok Yoon Jae Cheal Yoo Dong Kyu Moon Dong Kyun Woo 《International journal of medical sciences》2022,19(7):1131
Although melanogenesis is a defense mechanism against ultraviolet (UV)-induced skin damage, abnormally excessive melanin production causes pigmentation disorders. Tyrosinase, as a key factor for melanin synthesis, plays an important role in inducing skin pigmentation. Therefore, the inhibition of tyrosinase is crucial in preventing skin pigmentation in the cosmetics and medicine fields. However, the majority of well-known tyrosinase inhibitors have been discontinued due to toxic effects on the skin or lack of selectivity and/or stability. In this study, we evaluated possible anti-melanogenic effects of catechin-7-O-α-L-rhamnopyranoside (C7R) isolated from the stem bark of Ulmus parvifolia, to discover a new tyrosinase inhibitor that has both safety and stability. When C7R was pretreated in B16F10 melanoma cells stimulated by α-melanocyte-stimulating hormone, this compound reduced melanin accumulation and murine tyrosinase activity. In line with these results, C7R inhibits tyrosinase purified from a mushroom in vitro like kojic acid and arbutin. Furthermore, C7R exhibited a competitive inhibition on a Lineweaver-Burk plot. Next, the underlying mechanisms of the C7R-mediated tyrosinase inhibitory effect were sought through docking simulation and pharmacophore analysis between tyrosinase residues and C7R. The results of these analyses showed that C7R had binding energy of -14.5kcal/mol, and indicated that C7R interacts with tyrosinase through an aromatic ring and various hydrophobic and hydrogen bonds. Together, our results suggest that C7R can be applied as a novel natural anti-melanogenic agent that inhibits tyrosinase. 相似文献
84.
Gyu Man Oh Kyoungwon Jung Jae Hyun Kim Sung Eun Kim Won Moon Moo In Park Seun Ja Park 《Medicine》2022,101(30)
Among the plethora of foreign body impactions, fish bones are common examples that patients may struggle to properly disclose in clinical situations. This study investigated whether patients could pinpoint where the ingested fish bone was lodged. In addition, we investigated the differences between fish bone and other foreign bodies, the usefulness of computed tomography (CT), and the related risk factors for hospitalization. The cases of patients who underwent an endoscopic removal of fish bone between April 2008 and April 2020 were retrospectively reviewed. The clinical outcomes, X-ray scan, CT, and complications of each patient were investigated. A total of 96 patients were included in this study. The mean size of the impacted fish bone was 23.78 mm, and most were found in the upper esophagus (n = 38). There was a weak correlation between pain location and the actual lesion location (r = 0.419, P < .001). Compared to those of other foreign bodies, the location of impacted fish bones was different (P < .001), the X-ray detection rate of fish bones was lower (P < .001), and the complication incidence was higher (P = .030). CT (95.89%) showed higher sensitivity than X-ray scanning (11.24%) (P < .001). Foreign body size (P = .004) and door-to-endoscopy time (P = .029) were related to admission. Patients only managed to point out the approximate location of the ingested fish bone. CT detected fish bones well, but scans should include at least the entire esophagus instead of solely the area where pain is felt. Fish bone impaction has different clinical characteristics from other foreign bodies. Endoscopic removal without delay can reduce the admission rates. 相似文献
85.
Diet-induced obesity is one of the major causes of the development of metabolic disorders such as insulin resistance and nonalcoholic fatty liver disease (NAFLD). Recently, specific probiotic strains have been found to improve the symptoms of NAFLD. We examined the effects of Bifidobacterium animalis ssp. lactis MG741 (MG741) on NAFLD and weight gain, using a mouse model of high-fat-diet (HFD)-induced obesity. HFD-fed mice were supplemented daily with MG741. After 12 weeks, MG741-administered mice exhibited reduced fat deposition, and serum metabolic alterations, including fasting hyperinsulinemia, were modulated. In addition, MG741 regulated Acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), sterol regulatory element-binding protein 1 (SREBP-1), and carbohydrate-responsive element-binding protein (ChREBP) expression and lipid accumulation in the liver, thereby reducing the hepatic steatosis score. To determine whether the effects of MG741 were related to improvements in gut health, MG741 improved the HFD-induced deterioration in gut permeability by reducing toxic substances and inflammatory cytokine expression, and upregulating tight junctions. These results collectively demonstrate that the oral administration of MG741 could prevent NAFLD and obesity, thereby improving metabolic health. 相似文献
86.
Background/AimsWe investigated the effect of metabolic dysfunction-associated fatty liver disease (MAFLD) on future mortality and cardiovascular disease (CVD) using a prospective community-based cohort study.MethodsIndividuals from two community-based cohorts who were 40 to 70 years old were prospectively followed for 16 years. MAFLD was defined as a high fatty liver index (FLI ≥60) plus one of the following conditions overweight/obesity (body mass index ≥23 kg/m2), type 2 diabetes mellitus, or ≥2 metabolic risk abnormalities. Nonalcoholic fatty liver disease (NAFLD) was defined as FLI ≥60 without any secondary cause of hepatic steatosis.ResultsAmong 8,919 subjects (age 52.2±8.9 years, 47.7% of males), 1,509 (16.9%) had MAFLD. During the median follow-up of 15.7 years, MAFLD independently predicted overall mortality after adjustment for confounders (hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.05 to 1.69) but NAFLD did not (HR, 1.20; 95% CI, 0.94 to 1.53). MAFLD also predicted CVD after adjustment for age, sex, and body mass index (HR, 1.35; 95% CI, 1.13 to 1.62), which lost its statistical significance by further adjustments. Stratified analysis indicated that metabolic dysfunction contributed to mortality (HR, 1.51; 95% CI, 1.21 to 1.89) and CVD (HR, 1.27; 95% CI, 1.02 to 1.59). Among metabolic dysfunctions used for defining MAFLD, type 2 diabetes mellitus in MAFLD increased the risk of both mortality (HR, 2.07; 95% CI, 1.52 to 2.81) and CVD (HR, 1.42; 95% CI, 1.09 to 1.85).ConclusionsMAFLD independently increased overall mortality. Heterogeneity in mortality and CVD risk of subjects with MAFLD may be determined by the accompanying metabolic dysfunctions. 相似文献
87.
Wen-Jie Wu Shih-Wei Lin Woo Kyung Moon 《Computerized medical imaging and graphics》2012,36(8):627-633
To promote the classification accuracy and decrease the time of extracting features and finding (near) optimal classification model of an ultrasound breast tumor image computer-aided diagnosis system, we propose an approach which simultaneously combines feature selection and parameter setting in this study.In our approach ultrasound breast tumors were segmented automatically by a level set method. The auto-covariance texture features and morphologic features were first extracted following the use of a genetic algorithm to detect significant features and determine the near-optimal parameters for the support vector machine (SVM) to identify the tumor as benign or malignant.The proposed CAD system can differentiate benign from malignant breast tumors with high accuracy and short feature extraction time. According to the experimental results, the accuracy of the proposed CAD system for classifying breast tumors is 95.24% and the computing time of the proposed system for calculating features of all breast tumor images is only 8% of that of a system without feature selection. Furthermore, the time of finding (near) optimal classification model is significantly than that of grid search. It is therefore clinically useful in reducing the number of biopsies of benign lesions and offers a second reading to assist inexperienced physicians in avoiding misdiagnosis. 相似文献
88.
89.
L-amino acid oxidase prepared from Crotalus adamanteus venom after the method of
and
does not contribute to the production of the profound fall in systemic arterial pressure usually seen following injection of crude Crotalus venom, nor does it provoke any early deleterious changes in the dependent variables of the cardiovascular system.
The enzyme has no effect on neuromuscular transmission in the mammal. Its LD50 is 9·13 (7·83–10·35) mg per kg test animal body weight. 相似文献
90.
Introduction Aneurysms of the posterior cerebral artery (PCA) are rare, and most of the studies reported in the literature in which the
endovascular approach was applied were carried out on a limited number of patients with PCA aneurysms. We retrospectively
reviewed our cases of PCA aneurysms – at various locations and of differing shapes – that received endovascular treatment
and evaluated the treatment outcome.
Methods From January 1996 to December 2006, 13 patients (eight females and five males) with 17 PCA aneurysms (nine fusiform and eight
saccular) were treated using the endovascular approach. The age of the patients ranged from 20 to 67 years, with a mean age
of 44 years. Of the 13 patients, ten presented with intracranial hemorrhage, and one patient, with a large P2 aneurysm, presented
with trigeminal neuralgia; the aneurysms were asymptomatic in the remaining two patients.
Results All 13 patients were successfully treated, with only one procedure-related symptomatic complication. Seven patients were treated
by occlusion of the aneurysm and parent artery together; five patients, by selective embolization of the aneurysm; one patient,
by partial coiling. Although infarctions were found in two patients treated with selective embolization and in three patients
treated with parent artery occlusion, only one patient with a ruptured P2 aneurysm treated with parent artery occlusion developed
transient amnesia as an ischemic symptom.
Conclusion Posterior cerebral artery aneurysms can be treated safely with either occlusion of the aneurysm together with the PCA or with
a selective coil embolization. Infarctions may occur after endovascular treatment, but they are rarely the cause of a disabling
symptom. 相似文献