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931.
932.
Clinical Oral Investigations - The study objective was to investigate four common occlusal modes by using the finite element (FE) method and to conduct a biomechanical analysis of the periodontal...  相似文献   
933.
Odontology - The objective of this paper is to clarify the rate of abdominal obesity (AO), waist-to-height ratio (WHtR), metabolic syndrome (MetS) and determine the relationship with the...  相似文献   
934.
目的:探讨尼古丁对大鼠结合上皮(junctional epithelium,JE)根向迁移的影响.方法:20只6周龄雄性Wistar大鼠随机等分为实验组(每日腹腔注射尼古丁0.73 mg/kg)和对照组(每日腹腔注射等量生理盐水),每组再等分为30 d和90 d两个亚组;按实验设计处死后,常规制作右侧下颌磨牙区牙体-牙周联合组织的近远中向石蜡切片,Masson染色;测量第一磨牙釉牙骨质界-JE根端的长度.SPSS 26.0统计软件下各组数据行独立样本t检验.结果:30 d实验组和对照组相比,实验组大鼠JE出现轻度的根向迁移,但两组间无统计学意义(P>0.05).30 d组大鼠上皮下方的胶原均致密、粗大,排列整齐.对照、实验组90 d大鼠JE均有根向迁移,实验组迁移长度显著大于对照组(P<0.01),实验组比对照组上皮下方的胶原稀疏,纤细.不同时间点间比较,实验组90 d大鼠JE根向迁移长度明显大于实验组30 d,两组间有显著统计学意义(P<0.01).结论:本研究表明,大鼠的JE以时间依赖的方式在顶端迁移,腹腔注射尼古丁可以增强这种迁移.  相似文献   
935.
936.
Background: Hypermethylation in promoter regions of genes might lead to altered gene functions and result in malignant cellular transformation. Thus, biomarker identification for hypermethylated genes would be very useful for early diagnosis, prognosis, and therapeutic treatment of oral squamous cell carcinoma (OSCC). The objectives of this study were to screen and validate differentially hypermethylated genes in OSCC and correlate the hypermethylation-induced genes with demographic, clinocopathological characteristics and survival rate of OSCC.Methods: DNA methylation profiling was utilized to screen the differentially hypermethylated genes in OSCC. Three selected differentially-hypermethylated genes of p16, DDAH2 and DUSP1 were further validated for methylation status and protein expression. The correlation between demographic, clinicopathological characteristics, and survival rate of OSCC patients with hypermethylation of p16, DDAH2 and DUSP1 genes were analysed in the study.Results: Methylation profiling demonstrated 33 promoter hypermethylated genes in OSCC. The differentially-hypermethylated genes of p16, DDAH2 and DUSP1 revealed positivity of 78%, 80% and 88% in methylation-specific polymerase chain reaction and 24% and 22% of immunoreactivity in DDAH2 and DUSP1 genes, respectively. Promoter hypermethylation of p16 gene was found significantly associated with tumour site of buccal, gum, tongue and lip (P=0.001). In addition, DDAH2 methylation level was correlated significantly with patients'' age (P=0.050). In this study, overall five-year survival rate was 38.1% for OSCC patients and was influenced by sex difference.Conclusions: The study has identified 33 promoter hypermethylated genes that were significantly silenced in OSCC, which might be involved in an important mechanism in oral carcinogenesis. Our approaches revealed signature candidates of differentially hypermethylated genes of DDAH2 and DUSP1 which can be further developed as potential biomarkers for OSCC as diagnostic, prognostic and therapeutic targets in the future.  相似文献   
937.

Background

Astragali radix Antiasthmatic Decoction (AAD), a traditional Chinese medication, is found effective in treating allergic diseases and chronic cough. The purpose of this study is to determine whether this medication could suppress allergen-induced airway hyperresponsiveness (AHR) and remodeling in mice, and its possible mechanisms.

Methods

A mouse model of chronic asthma was used to investigate the effects of AAD on the airway lesions. Mice were sensitized and challenged with ovalbumin (OVA), and the extent of AHR and airway remodeling were characterized. Cells and cytokines in the bronchoalveolar lavage fluid (BALF) were examined.

Results

AAD treatment effectively decreased OVA-induced AHR, eosinophilic airway inflammation, and collagen deposition around the airway. It significantly reduced the levels of IL-13 and TGF-β1, but exerted inconsiderable effect on INF-γ and IL-10.

Conclusions

AAD greatly improves the symptoms of allergic airway remodeling probably through inhibition of Th2 cytokines and TGF-β1.
  相似文献   
938.
Liposomes are among the most successful nanocarriers; several products have been marketed, all of which were prepared by active loading methods. However, poorly water-soluble drugs without ionizable groups are usually incorporated into the lipid bi-layer of liposomes by passive loading methods, with serious drug leakage during blood circulation. Furthermore, there have been few improvements in their anti-cancer activity and safety. Herein, we designed and synthesized three weak-acid modified paclitaxel (PTX) derivatives with a one-step reaction for the remote loading of liposomal formulations. By comparison, PTX-succinic acid liposomes (PTX-SA LPs) exhibited the highest encapsulation efficiency (97.2 ± 1.8%) and drug loading (8.84 ± 0.16%); meanwhile, there was almost no change in their particle size or zeta potential within one month. Furthermore, compared with Taxol®, the PTX-SA LPs showed a 4.35-fold prolonged half-time, enhanced tumor accumulation, and an increased maximum tolerated dose (MTD) of more than 30 mg kg−1. As a result, the PTX-SA LPs displayed significantly improved in vivo anti-cancer efficacy in comparison with Taxol®. Therefore, weak-acid modification is proved to be a simple and effective method to achieve remote loading and high encapsulation efficiency of poorly soluble drugs, showing great potential for clinical application.

A remote loading liposomal formulation of weak-acid paclitaxel derivative with high encapsulation efficiency and high drug loading, improved therapeutic efficiency and negligible toxicity.  相似文献   
939.
Vesicles or micelles prepared from amphiphiles with azobenzene (Az) moieties and long alkyl chains have attracted much attention in drug delivery systems. To induce release behavior from smart carriers via transcis photoisomerization of the Az groups, UV light exposure is typically used, but it can damage DNA and hardly penetrates cells. In this paper, Az-containing phospholipids without long alkyl tails were designed and synthesized; in these compounds, the end group of the Az moiety was substituted with a –NO2 and –OCH3 group (abbreviated N6 and M6, respectively). N6 self-assembled into H-aggregates with an interdigitated bilayered structure in water through the antiparallel orientation due to π–π interactions of the Az group, the attractive van der Waals forces, and the interactions and bending behavior of the phosphocholine groups. Vesicles showing visible light stimuli-responsive behavior were obtained by mixing N6 and M6, and the release of encapsulated calcein was triggered by visible light.

A mixture of a nitro- and methoxy-substituted azo-containing phospholipids without long alkyl tails formed vesicles showing visible light stimuli-responsive behavior. Release of encapsulated calcein from the vesicles was triggered by visible light.  相似文献   
940.
目的构建基于信息化平台的糖尿病患者自我管理质量评价指标体系,为开展依托信息化平台的糖尿病管理提供借鉴。方法2018年8—11月,在文献回顾和专家会议法的基础上拟定指标体系初稿,通过德尔菲法对28名从事糖尿病诊疗、糖尿病护理、慢病管理、护理管理、护理教育等方面的专家进行2轮函询并构建最终指标体系。计算专家的积极性、权威性,专家意见的一致性、协调性。结果2轮专家函询问卷的有效回收率分别为93.33%和100.00%,专家权威系数分别为0.911和0.945。第2轮专家函询中,一、二、三级指标的肯德尔协调系数分别为0.478、0.478和0.537(P<0.01),变异系数均<0.25。最终构建的基于信息化平台的糖尿病患者自我管理质量评价指标体系包含3项一级指标、9项二级指标和69项三级指标。结论基于信息化平台的糖尿病患者自我管理质量评价指标构建过程严谨科学,指标内容比较合理、可靠性好,可为完善以信息化平台为支撑的糖尿病患者自我管理干预内容、提升糖尿病综合管理质量提供一定参考。  相似文献   
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