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Ulamnemekh Hulan Jav Sarantuya Baatarjav Tselmeg Mashbaljir Soyolmaa 《Pediatric Dental Journal》2010,20(2):171-176
Mutans streptococci, in particular Streptococcus mutans and Streptococcus sobrinus, are generally considered to be the principal microbial pathogen of dental caries. The objective of the study was to isolate S. mutans and S. sobrinus, identify them by PCR, and to compare their presence with the caries status and caries risk in Mongolian preschool and school children. Forty one preschool children aged 3–5 years and 40 school children aged 12–15 years were enrolled in this study. As assessed using Cariostat test, 75.6% of preschool children had high caries risk and 37.5% of school children had high caries risk. In preschool children, the prevalence of S. mutans and S. sobrinus were 100% and 36.6%, respectively; 63.4% were positive for S. mutans alone and 36.6% were positive for both S. mutans and S. sobrinus. In school children, the prevalence of S. mutans and S. sobrinus were 100% and 25.0%, respectively; 75.0% carried S. mutans alone and 25.0% had both S. mutans and S. sobrinus. The percentage of children positive for both S. mutans and S. sobrinus in the high caries risk group were significantly higher than those in the low risk group of either preschool (42.0% vs. 10.0%, P< 0.001) or school children (46.6% vs. 12.0%, P<0.001). Moreover, the caries status of children positive for both S. mutans and S. sobrinus were significantly higher than those positive for S. mutans alone (P< 0.01 for preschool children, and P< 0.05 for school children). 相似文献
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目的:通过研究蝉蜕不同提取部位对小鼠、豚鼠的止咳祛痰平喘作用,对蝉蜕有效部位进行筛选。方法:蝉蜕使用70%乙醇回流提取,所得浸膏依次用石油醚、乙酸乙酯、正丁醇萃取得各部分浸膏,受试动物随机分为对照组、阳性药组及不同提取部位组,采用小鼠氨水引咳法筛选止咳有效部位,小鼠酚红气管段法筛选祛痰有效部位,豚鼠整体药物引喘法筛选出平喘有效部位。结果:与对照组比较,蝉蜕70%乙醇提取物水部位有明显止咳作用(P0.05),正丁醇部位有祛痰作用(P0.01),乙酸乙酯、水部位具有明显平喘作用(P0.01)。结论:蝉蜕的止咳有效部位是水部位,祛痰部位为正丁醇部位,平喘部位是乙酸乙酯及水部位。 相似文献
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Francis H. Shen Brian C. Werner Haixiang Liang Hulan Shang Ning Yang Xudong Li Adam L. Shimer Gary Balian Adam J. Katz 《The spine journal》2013,13(1):32-43
Background contextHealthy mammalian cells in normal tissues are organized in complex three-dimensional (3D) networks that display nutrient and signaling gradients. Conventional techniques that grow cells in a 2D monolayer fail to reproduce the environment that is observed in vivo. In recent years, 3D culture systems have been used to mimic tumor microenvironments in cancer research and to emulate embryogenesis in stem cell cultures. However, there have been no studies exploring the ability for adipose-derived stromal (ADS) cells in a 3D culture system to undergo osteogenic differentiation.PurposeTo characterize and investigate the in vitro and in vivo potential for human ADS cells in a novel 3D culture system to undergo osteogenic differentiation.Study designBasic science and laboratory study.MethodsHuman ADS cells were isolated and prepared as either a 2D monolayer or 3D multicellular aggregates (MAs). Multicellular aggregates were formed using the hanging droplet technique. Cells were treated in osteogenic medium in vitro, and cellular differentiation was investigated using gene expression, histology, and microCT at 1-, 2-, and 4-week time points. In vivo investigation involved creating a muscle pouch by developing the avascular muscular interval in the vastus lateralis of male athymic rats. Specimens were then pretreated with osteogenic medium and surgically implanted as (1) carrier (Matrigel) alone (control), (2) carrier with human ADS cells in monolayer, or (3) human ADS cells as MAs. In vivo evidence of osteogenic differentiation was evaluated with micro computed tomography and histologic sectioning at a 2-week time point.ResultsHuman ADS cells cultured by the hanging droplet technique successfully formed MAs at the air-fluid interface. Adipose-derived stromal cells cultured in monolayer or as 3D MAs retain their ability to self-replicate and undergo multilineage differentiation as confirmed by increased runx2/Cbfa2, ALP, and OCN and increased matrix mineralization on histologic sectioning. Multicellular aggregate cells expressed increased differentiation potential and extracellular matrix production over the same human ADS cells cultured in monolayer. Furthermore, MAs reseeded onto monolayer retained their stem cell capabilities. When implanted in vivo, significantly greater bone volume and extracellular matrix were present in the implanted specimens of MAs confirmed on both microCT and histological sectioning.ConclusionsThis is the first study to investigate the capability of human ADS cells in a 3D culture system to undergo osteogenic differentiation. The results confirm that MAs maintain their stem cell characteristics. Compared with analogous cells in monolayer culture, the human ADS cells as MAs exhibit elevated levels of osteogenic differentiation and increased matrix mineralization. Furthermore, the creation of uniform spheroids allows for improved handling and manipulation during transplantation. These findings strongly support the concept that 3D culture systems remain not only a viable option for stem cell culture but also possibly a more attractive alternative to traditional culture techniques to improve the osteogenic potential of human adipose stem cells. 相似文献
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目的 通过湖北黄精、滇黄精、多花黄精根茎的转录组学分析,对影响不同品种黄精多糖含量的关键酶基因进行筛选和验证,并进行氨基酸序列的深入分析,丰富黄精属植物的转录组数据并为其多糖生物合成机制和遗传改良提供参考。方法 使用了Illumina NovaSeq高通量测序平台对黄精转录组进行测序分析,根据Nr、基因本体(GO)、京都基因与基因组百科全书(KEGG)数据库的注释分析比较3种黄精转录组的差异,筛选出多糖代谢途径中的关键酶,对关键酶基因表达量进行聚类分析并与多糖含量进行相关性分析,然后对筛选出的8个关键酶基因进行实时荧光定量聚合酶链式反应(Real-time PCR)验证,结合测序结果进一步筛选出多糖生物合成关键酶基因进行同源基因序列分析,构建系统进化树,预测模体(motif)、保守结构域、蛋白序列等电点与相对分子质量,并使用同源建模法构建三维蛋白结构。结果 通过Nr数据库的注释发现3种黄精与芦笋的基因同源性最高,GO数据库注释结果表明这3种黄精在结合功能、催化活性、代谢过程和细胞组分上差异显著,而KEGG通路注释结果说明这3种黄精在淀粉与蔗糖代谢通路和半乳糖代谢通路上差异显著,根据聚类分析、相关性分析、Real-time PCR验证实验、表达量情况与氨基酸序列的结构与功能预测推测出显著影响不同品种黄精多糖含量的关键酶为β-果糖苷酶(sacA)。结论 sacA可能是黄精多糖含量差异的主要影响因素,也是黄精多糖主要为果聚糖的重要原因。 相似文献
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Studies were carried out on Sprague-Dawley (SD) and Chester Beatty (CB) rats to determine whether the difference in incidence of myocardial lesions can be related to dietary factors and parameters known to be affected in SD rats fed rapeseed oils. The two strains of young, male rats were fed diets which contained 20% by weight of either corn, LEAR (low erucic acid) or HEAR (high erucic acid rapeseed) oils for a period of up to 16 weeks. A significantly lower incidence of focal myocardial necrosis was observed in CB rats than in SD rats. The incidence of this heart lesion in CB rats was similar between all diets; in SD rats a higher incidence was observed in the groups fed rapeseed oils. In both strains the growth rates of rats fed LEAR and corn oils were similar; growth rates with HEAR oil diets were much lower than the other oils. Severe myocardial lipidosis was only evident in rats fed HEAR oil, but no strain differences were observed. The pattern and extent of lipidosis, including cardiac and hepatic lipid levels and fatty acid compositions, were similar in both strains at the time periods studied. Cardiac triglycerides and free fatty acids increased in rats fed HEAR oil, but no strain differences were evident. Strain differences were found in the levels of a few cardiac phospholipids of rats fed HEAR oil, however, the relative fatty acid compositions of each phospholipid were remarkably similar. Microscopic examination of the livers showed no evidence that feeding rapeseed oil caused any specific effect which could be related to differences in heart lesion response. There was no evidence to indicate that differences in heart lesion response between the two rat strains could be related to cardiac triglycerides, free fatty acids or phospholipids. 相似文献
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老年人生活满意度及其影响因素研究 总被引:42,自引:0,他引:42
徐慧兰 《中国心理卫生杂志》1994,8(4):160-162
通过对长沙市1000例60岁以上老年人生活满意度及其影响因素调查,结果表明,长沙市老年人生活满意度均分为36.33±9.98(-x±SD)。说明大多数老人对其生活状况的主观感受是乐观的。通过逐步回归分析,影响老年人生活满意度主要因素为:职业、婚姻状况、经济状况、居住条件、生活来源、家庭关系、健康状况自评、日常生活能力以及自卑感、忧郁感、孤独感、情绪稳定状况等心理因素。 相似文献