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81.
82.
Systematic disinfection of the stethoscope diaphragm is required to ensure that it does not act as a vector for cross-transmission of health-related diseases. Thus, an antimicrobial latex film could be used as a cover to inhibit pathogenic bacteria from growing on its surface. The aim of this work is to determine the antimicrobial activity and mechanical properties of antimicrobial natural rubber (NR) latex films with different types of antimicrobial agents (mangosteen peel powder (MPP), zinc oxide nanoparticles (ZnO NP), and povidone-iodine (PVP-I)). The antimicrobial loading was varied from 0.5, to 1.0, and 2.0 phr to monitor the effective inhibition of Gram-negative bacteria and fungi growth. For MPP and PVP-I antimicrobial agents, a loading of 2.0 phr showed good antimicrobial efficacy with the largest zone of inhibition. Simultaneously, ZnO NP demonstrated excellent antimicrobial activity at low concentrations. The addition of antimicrobial agents shows a comparable effect on the mechanical properties of NR latex films. In comparison to control NR latex film (29.41 MPa, 48.49 N/mm), antimicrobial-filled films have significantly greater tensile and tear strengths (MPP (33.84 MPa, 65.21 N/mm), ZnO NP (31.79 MPa, 52.77 N/mm), and PVP-I (33.25 MPa, 50.75 N/mm). In conclusion, the addition of antimicrobial agents, particularly ZnO NP, can be a better choice for NR latex films because they will serve as both an activator and an antimicrobial. In a clinical context, with regard to frequently used medical equipment such as a stethoscope, such an approach offers significant promise to aid infection control. 相似文献
83.
目的 观察硬脂酸纳米吗啡(SLN-M)单次注入大鼠硬膜外腔后的镇痛效应.方法 选择硬膜外置管后无神经损伤症状的SD雄性大鼠50只,随机均分为五组.A组(假给药组):经硬膜外腔给予硬脂酸纳米(SLN);B1组与B2组:分别给予0.2及1 mg普通吗啡;C1组与C2组:分别给予含0.2及1 mg吗啡的SLN-M.用药后测定热痛阈值评价镇痛效果,以最大镇痛效应(MPE)表示,以SpO2、角膜反射的变化、僵直症的发生率对药物不良反应进行评估.结果 B1与C1组及B2与C2组的MPE最高值差异无统计学意义.但随时间延长,B1与B2组MPE逐渐下降,12 h后开始显著低于C1与C2组(P<0.05).B1与B2组达到MPE最高值的时间显著快于C1与C2组(P<0.05),但持续时间显著缩短(P<0.05).B1与B2组SpO2显著低于C1与C2组(P<0.05),角膜反射的变化和僵直症的发生率要高于C1与C2组(P<0.05),且与吗啡剂量呈正相关.结论 硬膜外腔单次给予SLN-M后可达到与普通吗啡一样的镇痛效果,有效镇痛时间明显延长,不良反应显著降低. 相似文献
84.
Ai Tsuji Yuka Ikeda Mutsumi Murakami Yasuko Kitagishi Satoru Matsuda 《Nutrition Research And Practice》2022,16(3):314
BACKGROUND/OBJECTIVESOocyte lipid droplets play a crucial role in meiosis and embryo development. Biotin is associated with fatty acid synthesis and is the coenzyme for acetyl-CoA carboxylase (ACC). The effects of a biotin deficiency on the oocyte lipid metabolism remain unknown. This study examined the effects of a biotin deficiency and its replenishment on murine 1) oocyte lipid droplet levels, 2) ovary lipid metabolism, and 3) oocyte meiosis.MATERIALS/METHODSMice were divided into 3 groups: control, biotin deficient (BD), and recovery groups. The control and BD groups were fed a control diet or BD diet (0.004 or 0 g biotin/kg), respectively. The recovery group mice were fed a BD diet until day 21, and were then fed the control diet from days 22 to 64. This study then quantified the oocyte lipid droplet levels, assessed the oocyte mitochondrial function, and examined the ability of oocytes to undergo meiosis. Ovarian phosphorylated ACC (p-ACC), lipogenesis, β-oxidation, and ATP production-related genes were evaluated.RESULTSThe BD group showed a decrease in lipid droplets and mitochondrial membrane potential and increased p-ACC levels. In the recovery group, the hepatic biotin concentration, ovarian p-ACC levels, and mitochondrial membrane potential were restored to the control group levels. On the other hand, the quantity of lipid droplets in the recovery group was not restored to the control levels. Furthermore, the percentage of oocytes with meiotic abnormalities was higher in the recovery group than in the control group.CONCLUSIONSA biotin deficiency reduced the oocyte lipid droplet levels by downregulating lipogenesis. The decreased lipid droplets and increased oocyte meiosis failure were not fully restored, even though the biotin nutrition status and gene expression of lipid metabolism was resumed. These results suggest that a biotin deficiency remains robust and can be long-lasting. Biotin might play a crucial role in maintaining the oocyte quality. 相似文献
85.
Payank Patel Amit Roy Navid Sharifi Pantcho Stoyanov Richard R. Chromik Christian Moreau 《Materials》2022,15(10)
Surface coatings that operate effectively at elevated temperatures provide compatibility with critical service conditions as well as improved tribological performance of the components. High-entropy coatings (HECs), including metallic, ceramics, and composites, have gained attention all over the world and developed rapidly over the past 18 years, due to their excellent mechanical and tribological properties. High-entropy alloys (HEAs) are defined as alloys containing five or more principal elements in equal or close to equal atomic percentage. Owing to the high configurational entropy compared to conventional alloys, HEAs are usually composed of a simple solid solution phase, such as the BCC and FCC phases, instead of complex, brittle intermetallic phases. Several researchers have investigated the mechanical, oxidation, corrosion and wear properties of high-entropy oxides, carbides, borides, and silicates using various coating and testing techniques. More recently, the friction and wear characteristics of high-entropy coatings (HECs) have gained interest within various industrial sectors, mainly due to their favourable mechanical and tribological properties at high temperatures. In this review article, the authors identified the research studies and developments in high-entropy coatings (HECs) fabricated on various substrate materials using different synthesis methods. In addition, the current understanding of the HECs characteristics is critically reviewed, including the fabrication routes of targets/feedstock, synthesis methods utilized in various research studies, microstructural and tribological behaviour from room temperature to high temperatures. 相似文献
86.
Ysmael Verde-Gmez Elizabeth Montiel-Macías Ana María Valenzuela-Muiz Ivonne Alonso-Lemus Mario Miki-Yoshida Karim Zaghib Nicolas Brodusch Raynald Gauvin 《Materials》2022,15(10)
In the past few decades, nanostructured carbons (NCs) have been investigated for their interesting properties, which are attractive for a wide range of applications in electronic devices, energy systems, sensors, and support materials. One approach to improving the properties of NCs is to dope them with various heteroatoms. This work describes the synthesis and study of sulfur-added carbon nanohorns (S-CNH). Synthesis of S-CNH was carried out by modified chemical vapor deposition (m-CVD) using toluene and thiophene as carbon and sulfur sources, respectively. Some parameters such as the temperature of synthesis and carrier gas flow rates were modified to determine their effect on the properties of S-CNH. High-resolution scanning and transmission electron microscopy analysis showed the presence of hollow horn-type carbon nanostructures with lengths between 1 to 3 µm and, diameters that are in the range of 50 to 200 nm. Two types of carbon layers were observed, with rough outer layers and smooth inner layers. The surface textural properties are attributed to the defects induced by the sulfur intercalated into the lattice or bonded with the carbon. The XRD patterns and X-ray microanalysis studies show that iron serves as the seed for carbon nanohorn growth and iron sulfide is formed during synthesis. 相似文献
87.
目的:观察六味地黄汤加减治疗老年阴虚阳亢型高血压的临床效果。方法:选取阴虚阳亢型老年高血压患者117例,随机分为对照组57例和治疗组60例。对照组给予苯磺酸氨氯地平片口服治疗,治疗组给予六味地黄汤加减治疗。结果:对照组有效率为78.9%,治疗组有效率为91.7%,治疗组优于对照组(P0.05);治疗组治疗后舒张压、收缩压、C反应蛋白、总胆固醇、低密度脂蛋白、三酰甘油水平均优于对照组(P0.05)。结论:六味地黄汤加减治疗老年阴虚阳亢型高血压疗效显著。 相似文献
88.
AIM: To analyse the association between dyslipidemia and severity of meibomian gland dysfunction (MGD) in a tertiary care hospital of Uttarakhand region.
METHODS: This prospective observational study was conducted over a period of one year including 50 consecutive patients of MGD. Patients underwent detailed history (including Ocular Surface Disease Index Questionnaire) and examination (including meibum quality, expressibility and numerical staining). MGD was graded according to the guidelines submitted by the International Workshop on Meibomian Gland Dysfunction and Management in 2011. Fasting lipid profile of all the patients was done. Various parameters of lipid profile including total cholesterol (TC), triglycerides (TG), low density lipoproteins (LDL), high density lipoproteins (HDL) and very low density lipoproteins (VLDL) were correlated with MGD severity. Chi-square test was done for statistical analysis (P<0.05).
RESULTS: Stage 2 MGD was the most common disease entity (60%, n=30). A significant positive correlation was noted between increasing age and severity of MGD (P=0.004). High TC (>200 mg/dL), TG (>150 mg/dL), LDL (>130 mg/dL) and VLDL (>22 mg/dL) levels had a significant positive correlation with the severity of MGD (P=0.001, 0.019, 0.001, 0.016 respectively).
CONCLUSION: Monitoring the fasting lipid levels may aid in establishing the severity of MGD and further studies may be conducted to establish the role of treatment of dyslipidemia in MGD. 相似文献
89.
目的介绍近年来胰岛素纳米粒制剂研究进展。方法查阅国内外胰岛素纳米粒的相关文献资料,从吸收机制、制备、检测方法及其发展等方面进行整理和归纳。结果与结论目前胰岛素纳米粒的研究已广泛开展,取得了令人瞩目的成就,发展空间广阔。 相似文献
90.
Shuting Qiu Jiajia Chen Yan Bai Jincan He Hua Cao Qishi Che Jiao Guo Zhengquan Su 《Nutrients》2022,14(13)
The treatment of nonalcoholic fatty liver disease (NAFLD) remains very challenging. This study investigated the therapeutic effect of galactose oligosaccharide (GOS), an important prebiotic, on NAFLD through in vivo and in vitro experiments and preliminarily explored the mechanism by which GOS improves liver lipid metabolism and inflammation through liver and intestinal microbiological analysis. The results of mouse liver lipidomics showed that GOS could promote body thermogenesis in mice with high-fat and high-sugar diet (HFHSD)-induced NAFLD, regulate lipolysis in liver fat cells, and accelerate glycine and cholesterol metabolism. GOS dose-dependently reduced the contents of total cholesterol (TC) and triglyceride (TG) in cells and reduced the accumulation of lipid droplets in cells. GOS also reduced the Firmicutes/Bacteroidetes ratio and altered the composition of the intestinal microbiota in mice fed a HFHSD. GOS can improve liver lipid metabolism and intestinal structure of NAFLD. These results provide a theoretical and experimental basis supporting the use of GOS as a health food with anti-NAFLD functions. 相似文献