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1.
《Dental materials》2022,38(2):397-408
ObjectivesComposite restorations with calcium fluoride nanoparticles (nCaF2) can remineralize tooth structure through F and Ca ion release. However, the persistence of ion release is limited. The objectives for this study were to achieve long-term remineralization by developing a rechargeable nCaF2 nanocomposite and investigating the F and Ca recharge and re-release capabilities.MethodsThree nCaF2 nanocomposites were formulated: (1) BT-nCaF2:Bisphenol A glycidyl dimethacrylate (BisGMA) and triethylene glycol dimethacrylate (TEGDMA); (2) PE-nCaF2:Pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA); (3) BTM-nCaF2:BisGMA, TEGDMA, and Bis[2-(methacryloyloxy)ethyl] phosphate (Bis-MEP). All formulations contained 15% nCaF2 and 55% glass particles. Initial flexural strength and elastic modulus, F and Ca ion release, recharge and re-release were tested and compared to three commercial fluoride-containing materials.ResultsBT and BTM nCaF2 composites were 3–4 times stronger and had elastic modulus 2 times that of resin-modified glass ionomer controls. PE-nCaF2 had comparable strength to RMGIs. All nCaF2 composites had significant F and Ca ion release and ion rechargeability. In F and Ca recharging cycles, PE-nCaF2 had the highest ion recharging capability among nCaF2 groups, followed by BT-nCaF2 and BTM-nCaF2 (p < 0.05). For all recharge cycles, ion release maintained similar levels, demonstrating long-term ion release was possible. Furthermore, after the final recharge cycle, nCaF2 nanocomposites provided continuous ion release for 42 days without further recharge.SignificanceNovel nCaF2 rechargeable nanocomposites exhibited significant F and Ca ion release over multiple recharge cycles, demonstrating continuous long-term ion release. These nanocomposites are promising restorations with lasting remineralization potential.  相似文献   
2.
目的评价不同消毒方法对清洁用具和地面洁净程度的影响。方法清洁用具分别采用化学消毒剂浸泡和机械热力消毒,用ATP拭子对消毒前后的清洁用具和病房地面采样,使用ATP荧光检测仪进行分析,比较不同消毒方法的效果。结果地面清洁消毒前拖把表面RLU值为137.00±20.98,地巾表面RLU值为1.20±0.84,地巾表面RLU值水平低于拖把表面,差异具有统计学意义(Z=-2.63,P<0.001)。清洁后拖把组地面平均RLU值减少24.78%,地巾组地面平均RLU值减少55.52%,差异具有统计学意义(Z=-6.03,P<0.001)。结论机械热力消毒处理的地巾比化学消毒剂浸泡的拖把洁净程度更高,采用机械热力消毒后的地巾清洁的地面也更干净。  相似文献   
3.
目的 采用响应面法优选三七生药粉乙醇灭菌工艺,考察不同灭菌方式对三七生药粉灭菌效果及质量的影响。方法 以人参皂苷Rg1、人参皂苷Rb1及三七皂苷R1含量,皂苷总量和灭菌率的综合评分为指标,乙醇体积分数、乙醇用量、灭菌时间、干燥温度为因素,在单因素试验的基础上,采用响应面法优化三七乙醇灭菌工艺;分别对比湿热灭菌、辐照灭菌、干热灭菌和乙醇灭菌法对三七生药粉灭菌效果和质量的影响。结果 最佳灭菌工艺为乙醇体积分数74%、乙醇用量26%、灭菌时间2.2 h、干燥温度75 ℃;对比灭菌前后三七粉的质量,湿热灭菌和干热灭菌后三七中皂苷含量显著降低,其中湿热灭菌后皂苷含量已不符合《中华人民共和国药典》2020年版标准。指纹图谱显示,乙醇灭菌与生药材相似度较高,表明乙醇灭菌对三七影响不大。结论 乙醇灭菌法与其他灭菌方法相比,可在较低温度、更短时间、更加安全地得到符合规定的三七生药粉,且优选得到的灭菌工艺稳定可行、重复性好,可为其后续工艺开发和工业化生产提供参考。  相似文献   
4.
The effects of climate change include floods, hurricanes, heat waves, and fires; these natural disasters can result in respiratory, cardiovascular, and psychological harm in older adults, who experience the highest morbidity and mortality during heat waves. Advanced practice registered nurses (APRNs) need education on preparing, assessing, and treating older adults for climate-change disasters, especially heat waves. This article will help APRNs understand the effects of climate-change events on the vulnerable older adults and advocates for the need to integrate health effects of climate change into curricula, practicums, policy, and research agendas.  相似文献   
5.
《Dental materials》2022,38(2):421-430
ObjectivesTo determine the long-term effect on the stability of dentin-resin interfaces after the addition of polylactide (PLA) capsules containing proanthocyanidin (PAC) to adhesive resin.MethodsSub-micron (SM) and micron (M) size capsules containing PACs were produced using a combination of emulsification and solvent evaporation techniques and characterized. Human dentin surfaces (n = 8) were etched (35% glycolic acid) and primed (15% enriched Vitis vinifera extract solution - VVe), followed by the application of an experimental adhesive containing 0 (control), 1.5 wt% of SM or M PAC-filled PLA capsules light cured for 40 s. A crown was built using commercial composite. After 24 h-immersion (37 °C) in simulated body fluid, specimens were serially sectioned into resin-dentin beams. Microtensile bond strength (TBS), micro-permeability and fracture pattern were assessed immediately and after 1 and 2 years. Data were statistically analyzed using two-way ANOVA and post-hoc test (α = 0.05).ResultsPolydisperse capsules were manufactured with average diameter of 0.36 µm and 1.08 µm for SM and M, respectively. The addition of capsules did not affect TBS (p = 0.889). After 2 years, TBS significantly decreased in SM (p = 0.006), whereas M showed similar initial values (p = 0.291). Overall, less micro-permeability was found in M than the control and SM group (p < 0.001). After 2 years, fractured surfaces from capsule-containing groups failed within the adhesive layer while control fractured at the bottom of the hybrid layer.SignificanceThe addition of PAC-filled PLA microcapsules in a dental adhesive did not affect the bond strength while increased and sustained the protection against micro-permeability in the interface, likely due to release of PACs.  相似文献   
6.
耿翔  王之枫  王晨  张超  王旭  马昕 《中国骨伤》2022,35(9):830-835
目的:探讨微创Chevron合并外侧软组织松解治疗轻中度拇外翻畸形的短期疗效。方法:自2019年1月至2021年12月,采用微创Chevron截骨加外侧软组织松解术式治疗67例(80足)轻中度拇外翻患者,男5例(6足),女62例(74足);年龄20~60(47.2±9.7)岁;轻度(拇外翻角 ≤ 20°)54例(64足),中度(20°<拇外翻角 ≤ 40°)13例(16足)。比较术前与末次随访时拇外翻角(hallux valugs angle,HVA),Ⅰ-Ⅱ跖骨间角(Ⅰ-Ⅱ intermetatarsal anlge,Ⅰ-Ⅱ IMA),远端跖骨关节角(distal metatarsal articular angle,DMAA),籽骨Hardy评分变化,并采用北美足踝外科协会拇趾-跖趾关节(American Orthopaedic Foot and Ankle Society''s Hallux Metatarsophalanged-Interphalangeal,AOFAS Hallux MTP-IP)评分进行疗效评价。结果:67例患者获得随访,时间6~23(13.7±6.5)个月。术前HVA、Ⅰ-Ⅱ IMA、DMAA、籽骨Hardy评分、AOFAS Hallux MTP-IP评分分别为(27.5±7.0)°,(17.4±4.1)°,(11.4±3.8)°,(4.9±2.6)分,(58.2±9.1)分;末次随访时时分别为(8.3±4.8)°,(6.9±3.0)°,(3.9±2.4)°,(2.7±1.1)分,(91.3±2.2)分;术前与末次随访比较差异有统计学意义(P<0.05)。轻度患足(64足)和中度患足(16足)术前各项影像学指标和AOFAS Hallux MTP-IP评分比较差异有统计学意义(P<0.05);末次随访时,上述指标比较差异无统计学意义(P>0.05);从各指标改善程度来看,中度拇外翻患足HVA、Ⅰ-ⅡIMA、籽骨Hardy评分、AOFAS Hallux MTP-IP评分优于轻度拇外翻患足(P<0.05)。术后4例出现截骨部位切口周围红肿,经局部换药及口服抗生素均治愈。结论:微创Chevron截骨联合外侧软组织松解术对于轻中度拇外翻有良好的矫形效果及功能改善。  相似文献   
7.
BackgroundVitamin D is essential in the host defense against tuberculosis (TB). Suboptimal vitamin D status is common in the hemodialysis population. Hemodialysis patients have an increased risk compared to the general population latent tuberculosis infection (LTBI). However, the association between vitamin D deficiency and LTBI in this population remains unclear.Materials and methodsWe conducted a cross-sectional study between March and May 2017. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-Tube was used to assess LTBI. Plasma 25-hydroxycholecalciferol (25-OHD) levels were measured by Elecsys Vitamin D Total assay. Suboptimal vitamin D levels included vitamin D insufficiency 20–29 ng/mg and vitamin D deficiency <20 ng/mL. Predictors for LTBI were analyzed.ResultsA total of 287 participants were enrolled. The suboptimal vitamin D level was 31.4% (90/287), which including the vitamin D deficiency was 13.9% (40/287). A total of 49.1% (141/287) people received nutritional vitamin D supplementation. The prevalence of IGRA positivity in this study was 25.1% (72/287). There was no significant difference in vitamin D concentrations or the proportion of vitamin D supplementation among the IGRA-positive and IGRA-negative groups (p = 0.789 and 0.496, respectively). In multivariate analysis, age >65 years old (odds ratio (OR), 1.89; 95% CI, 1.08–3.31; p = 0.026) and TB history (OR, 3.51; 95% CI, 1.38–8.91; p = 0.008) were independent predictors of IGRA positivity.ConclusionThis is the first study to report that vitamin D deficiency was not associated with IGRA positivity in a hemodialysis population. Aging and TB history were both independent predictors for LTBI.  相似文献   
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10.
目的:探析慢性肾脏病患者采取非洛地平缓释片联合百令胶囊治疗对改善肾功能指标的效果。方法:选取2016年11月至2020年7月芜湖市第一人民医院收治的慢性肾脏病患者60例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组30例。对照组采用非洛地平缓释片治疗,观察组采用非洛地平缓释片联合百令胶囊治疗,比较2组患者尿素氨(BUN)水平、血肌酐(SCr)、24 h尿蛋白定量、胱抑素C(Cys-C)、血清降钙素原(PCT)、超敏C反应蛋白(hs-CRP)以及治疗有效率等指标。结果:观察组患者的BUN、SCr、24 h尿蛋白定量、Cys-C等肾功能水平降低幅度明显大于对照组,差异有统计学意义(P<0.05);观察组患者PCT、hs-CRP等炎症介质水平降低幅度明显大于对照组,差异有统计学意义(P<0.05);观察组、对照组治疗有效率分别为96.67%、76.67%,观察组治疗有效率明显高于对照组,差异有统计学意义(P<0.05)。结论:慢性肾脏病患者采取百令胶囊联合非洛地平缓释片进行治疗在改善肾功能、炎症介质方面有着非常明显的优势,还可提升治疗有效率,对改善患者治疗预后有着明显的优势,应推广应用。  相似文献   
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