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31.
目的探讨健脾方药四君子汤多糖提取物、黄芪甲苷对小鼠小肠类器官的干预作用。方法取4~6周龄小鼠小肠约20 cm,经过清洗、剪切、消化,分离出小肠隐窝细胞团后,接种于含有多种细胞因子的基质胶中,在基质胶3D结构支撑下,培养形成具有小肠上皮样形态的立体多叶结构,即小肠类器官。光镜下观察小肠类器官的形态特征;采用免疫荧光染色后在激光共聚焦显微镜下观察E-钙黏蛋白(E-cadherin)的表达;传代2天后的小鼠小肠类器官分为3组:对照组、四君子多糖组(终浓度为100 mg/L)以及黄芪甲苷组(终浓度为10μmol/L),继续培养48 h后观察四君子汤多糖提取物、黄芪甲苷对小肠类器官出芽生长及增殖细胞核核抗原Ki-67表达。结果分离出的小鼠隐窝细胞团1天类似囊状,中心具有单个内腔;2~3天开始出芽;4~5天出芽增多,管腔结构进一步清晰,形成小肠类器官,初步建立了小肠类器官培养模式;四君子多糖组(100 mg/L)小肠类器官出芽数量较对照组明显增多(2.31±1.60vs 4.15±1.91,P<0.05);黄芪甲苷组较对照组中小肠类器官Ki-67表达明显增高。结论小肠类器官模型的构建为探讨肠黏膜修复的病理生理机制及药物干预提供了更完善的体外研究模型。四君子汤多糖提取物、黄芪甲苷的肠黏膜保护作用可能与其促进隐窝干细胞更新能力有关。 相似文献
32.
Luke D. Kim Elizabeth R. Pfoh Bo Hu Lei Kou Lisa M. Knowlton Kristan Staudenmayer Michael B. Rothberg 《Journal of the American Medical Directors Association》2019,20(9):1086-1090.e2
ObjectivesTo identify factors associated with 30-day all-cause readmission rates in surgical patients discharged to skilled nursing facilities (SNFs), and derive and validate a risk score.DesignRetrospective cohort.Setting and participantsPatients admitted to 1 tertiary hospital's surgical services between January 1, 2011, and December 31, 2014 and subsequently discharged to 110 SNFs within a 25-mile radius of the hospital. The first 2 years were used for the derivation set and the last 2 for validation.MethodsData were collected on 30-day all cause readmissions, patient demographics, procedure and surgical service, comorbidities, laboratory tests, and prior health care utilization. Multivariate regression was used to identify risk factors for readmission.ResultsDuring the study period, 2405 surgical patients were discharged to 110 SNFs, and 519 (21.6%) of these patients experienced readmission within 30 days. In a multivariable regression model, hospital length of stay [odds ratio (OR) per day: 1.03, 95% confidence interval (CI) 1.02-1.04], number of hospitalizations in past year (OR 1.24 per hospitalization, 95% CI 1.18-1.31), nonelective surgery (OR 1.33, 95% CI 1.18-1.65), low-risk service (orthopedic/spine service) (OR 0.32, 95% CI 0.25-0.42), and intermediate-risk service (cardiothoracic surgery/urology/gynecology/ear, nose, throat) (OR 0.69, 95% CI 0.53-0.88) were associated with all-cause readmissions. The model had a C index of 0.71 in the validation set. Using the following risk score [0.8 × (hospital length of stay) + 7 × (number of hospitalizations in past year) +10 for nonelective surgery, +36 for high-risk surgery, and +20 for intermediate-risk surgery], a score of >40 identified patients at high risk of 30-day readmission (35.8% vs 12.6%, P < .001).Conclusions/ImplicationsAmong surgical patients discharged to an SNF, a simple risk score with 4 parameters can accurately predict the risk of 30-day readmission. 相似文献
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35.
《Dental materials》2019,35(12):1805-1812
ObjectiveThe aim of this study was to investigate the three-body wear of different additively manufactured temporary materials, one temporary PMMA material for CAD/CAM milling and one resin-based composite for direct restorations as a control group by using an ACTA machine.MethodsSpecimens (n = 8) of the 3D printing materials 3Delta temp, NextDent C&B, Freeprint temp were additively manufactured by DLP 3D printer. Postprocessing was carried out according to the manufacturer's specifications. Telio CAD were cut out of blocks, Tetric EvoCeram was applied directly and light cured. Three-body wear was simulated with an ACTA machine. Data were statistically analysed (ANOVA, post hoc test: Tukey, p < 0.05). The worn surfaces of the specimens were examined with a FE-SEM.ResultsThe average mean wear was 50 ± 15 μm for Tetric EvoCeram < 62 ± 4 μm for 3Delta temp < 236 ± 31 μm for Telio CAD < 255 ± 13 μm for NextDent C&B < 257 ± 24 μm for Freeprint temp. After 200,000 cycles, the wear and wear rates for Tetric EvoCeram and 3Delta temp were significantly lower than those for the other materials. SEM revealed that 3Delta temp has a higher filler proportion than the other 3D printing materials but less than Tetric EvoCeram.SignificanceThe filler content influences the wear behaviour of additively manufactured materials as well as dental restorative composite materials. While most 3D printing materials have a low inorganic filler load, which qualifies the materials for temporary use only, one 3D printing material has an optimized composition that would qualify the material for longer clinical service time if wear is considered as the outcome variable. 相似文献
36.
糖尿病心肌病(Diabetic Cardiomyopathy,DC)的进展会导致左心室功能减低,因此,早期正确评估左心室功能对糖尿病心肌病患者的治疗和预后有着重要的意义。由于左心室解剖结构的复杂性,常规超声技术通常很难准确的评估左心室功能的变化,三维斑点追踪技术(three-dimensional speckle tracking imaging,3D-STI)是在实时3D超声和斑点追踪技术(STI)基础上发展起来的一项新技术,其对心脏功能的评估不受整个心脏运动方向和运动幅度的限制,能够直观的对心肌各个方向的运动进行追踪。本文首先论述3D-STI 在左心室功能评价中的可行性,再对其在DC左心室功能评价中的研究展开综述。 相似文献
37.
目的基于多元统计分析和网络药理学分析预测五味子醋制前后潜在的质量标志物。方法采用UPLC-Q/TOF-MS解析生、醋五味子饮片中主要的木脂素类成分,并运用多元统计方法筛选出炮制前后潜在的差异化学成分,即化学标记物。进一步通过网络药理学以及生物信息学分析显著差异成分相关的主要作用靶点和通路,构建"成分-靶点-通路"网络关系,预测生、醋五味子潜在的质量标志物。结果筛选了五味子醋制前后差异性成分40个,其中8个为生、醋五味子之间显著性差异成分(即化学标记物)。鉴定并确认了其中的5个化学成分,分别是5-羟甲基糠醛、五味子甲素及其同分异构体、五味子乙素和五味子酯丁。而其余3个化学标记物通过解析一级、二级质谱信息,推测它们很可能也属于木脂素类成分。网络药理学分析结果表明,鉴定并确认的5个潜在质量标志物与五味子的主要药理作用密切相关。最终五味子乙素和5-羟甲基糠醛被确定为最具代表性的潜在质量标志物。结论五味子醋制前后其化学成分发生了一系列复杂的变化,经研究分析确定五味子乙素和5-羟甲基糠醛可作为五味子醋制前后代表性的潜在质量标志物,并推测木脂素类成分可能为五味子醋制保肝的重要效应物质基础。 相似文献
38.
Amrollah Sharifi Homayoon Vahedi Saharnaz Nedjat Hossein Rafiei Mohammad Javad Hosseinzadeh‐Attar 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2019,127(10):681-687
Ulcerative colitis (UC) is a chronic recurrent inflammation of the colon. It has been proposed that the UC pathogenesis may be related to vitamin D deficiency and/or vitamin D administration in UC patients may have an ameliorating effect on the intestinal inflammation. The aim of this study was to assess the effect of vitamin D on the serum levels of immune cytokines in UC patients. In this double‐blind randomized controlled trial, 90 mild‐to‐moderate UC patients were assigned to get either a single muscular injection of 7.5 mg vitamin D3 or 1 mL normal saline as placebo. Three months later serum levels of IL‐4, IL‐10, IL‐12p70, IFN‐γ, and TNF‐α were measured. Two group variables were compared using independent t‐test and analysis of covariance (ANCOVA). There was a significant increase in vitamin D only in the vitamin D group. Compared to placebo, vitamin D had significant decreasing effects on serum TNF‐α, IFN‐γ, and IL12p70 levels, but it had no significant effect on serum levels of IL4 and IL10. Vitamin D seems to inhibit Th1 immune responses and have no effect on Th2 responses. The findings of this study support several in vitro studies, which suggest a therapeutic immunomodulatory potential of vitamin D. 相似文献
39.