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61.
目的:推断并验证大黄、地榆、牡丹皮3味中药炒炭的热解反应机制,进一步完善这3味中药炒炭研究的理论。方法:采用模式函数法中的单个扫描速率的不定温法(Coats-Redfern模型与Achar模型)推断大黄、地榆、牡丹皮3味中药炒炭过程中热解反应的机理函数,通过比较转化率(α)理论值、实验值与1/T的热分析曲线对机理函数进行验证。结果:积分形式表达式能更较好地描述大黄、地榆、牡丹皮3味中药炒炭热解的反应机制,三者的炒炭热解机理函数分别为9号机理函数积分形式g(α)=[(1-α)-1/3-1]2,2号机理函数积分形式g(α)=α+(1-α)ln(1-α),9号机理函数积分形式g(α)=[(1-α)-1/3-1]2。结论:3味中药炒炭的热解反应机制均属于反应扩散,转化率理论值与实验值存在一定的差异,运用热分析动力学方法只是尽可能地模拟这3味中药的炒炭热解反应过程。 相似文献
62.
目的:观察扶正抗癌(FZKA)方对肺癌细胞A549增殖的调控作用,探讨其作用的分子机制。方法:以非小细胞肺癌细胞A549为研究对象,以FAKA方0.8,1.2,1.6,2.0,2.4,2.8,3.2 g·L~(-1)干预,空白组,分别孵育24,48,72 h后,设立采用噻唑蓝(MTT)比色法检测FZKA方对A549细胞活力的影响;以FAKA方1.2,1.6,2.0 g·L~(-1)干预,设立空白组,培养24 h后,采用实时荧光定量聚合酶链式反应(Real-time PCR)检测FZKA方对A549细胞人第10号染色体同源丢失性磷酸酶-张力蛋白(phosphatase and tensin homolog deleted on chromosome ten,PTEN)mRNA水平的影响;孵育24 h后,采用蛋白质免疫印迹法(Western blot)分析FZKA方对PTEN,磷脂酰肌醇3-激酶(phosphatidylinositol-3-kinase,PI3K),磷酸化的促凋亡蛋白Bad(Phospho-Bad,p-Bad)表达的影响并探讨其相关性。结果:与空白组比较,FZKA方能明显抑制A549细胞增殖,处理24 h后,FZKA从0.8 g·L~(-1)开始,处理48,72 h后,FZKA方从0.4 g·L~(-1)开始,细胞存活率明显降低(P0.05,P0.01);与空白组比较,处理24 h后,FZKA方从0.8 g·L~(-1)开始以浓度依赖性上调PTEN mRNA和蛋白的表达(P0.05,P0.01),FZKA方从1.6 g·L~(-1)开始以浓度依赖性下调PI3K蛋白表达(P0.05,P0.01),从2 h开始以时间依赖性上调p-Bad蛋白的表达(P0.05,P0.01)。结论:FZKA方可通过上调PTEN来调控下游PI3K/Akt/Bad通路相关蛋白的表达进而抑制A549的增殖,促进肺癌细胞凋亡。 相似文献
63.
目的:优选补骨脂酚的提取纯化工艺,并考察其对骨质疏松症的治疗作用。方法:使用乙醇回流法提取,经D101型大孔树脂纯化,通过单因素试验优选工艺条件,冷冻干燥后得到补骨脂酚;采用斑马鱼体内试验评价补骨脂酚对骨密度和骨骼发育钙化的影响。结果:优选的工艺条件为加8倍量85%乙醇浸泡过夜,回流提取3次,每次2 h,边搅拌边往补骨脂酚粗提物中加入0.2%氢氧化钠水溶液至完全溶解,过预处理好的D101型大孔树脂柱处理,上样流速1 BV·h~(-1),静置4 h,加水6 BV洗脱,用60%乙醇2 BV洗脱,加95%乙醇4 BV洗脱,收集95%乙醇的洗脱液;制备的补骨脂酚质量分数80%,收率10%。斑马鱼体内活性研究表明补骨脂酚能提高斑马鱼骨质疏松症的骨密度,且能促进正常斑马鱼骨骼发育钙化。结论:此工艺具有绿色环保、操作简便等优点,所得补骨脂酚的纯度和收率均比较理想,可开发成预防或治疗骨质疏松症的药品和食品。 相似文献
64.
目的:研究考察川芪眼用微乳原位凝胶的流变学及释放动力学行为,为该制剂的后续研究与开发提供参考。方法:使用MCR 102型流变仪考察川芪眼用微乳原位凝胶的流体性质及线性粘弹区域。体外释放度采用改良Franz扩散池法,以半透膜为释放膜,川芎嗪、藁本内酯为指标成分,取样时间点分别为0.5,1,2,4,6,8 h。结果:川芪眼用微乳原位凝胶是一种假塑性流体并存在线性粘弹区域。以剪切力为指标,确定的线性粘弹区域为0~302.74 Pa,以形变为指标得到的线性粘弹区域范围为0~7.45%。在临界点时,其储能模量(G')等于损耗模量(G″),均为2 976.60 Pa;临界剪切力为302.74 Pa;临界形变7.45%。8 h内6份样品中川芎嗪的平均累积释放量33.71μg,平均累积释放率90.08%,释放动力学遵循Higuchi方程。8 h内6份样品中藁本内酯平均累积释放量为68.46μg,平均累积释放率为84.32%,其释放动力学遵循零级动力学方程。结论:川芪眼用微乳原位凝胶具有较好的粘弹性,并在一定范围内可以发生可逆形变。川芎嗪释放动力学是川芎嗪的理化性质与基质骨架共同作用的结果,藁本内酯的释放动力学主要受其理化性质的影响。 相似文献
65.
66.
The appropriateness of dental manpower has become a great uncertainty in the changing practice of dentistry. This paper presents research on the requirement for and supply of dental services in Victoria between 1984 and 1996. The requirement for dental services was found to be increasing due to population growth and higher per capita demand due to decreased endentulism. The supply of dental services was found to be mildly decreasing due to balanced supplementation and attrition processes and subtle sex ratio and age distribution changes among dentists. The resulting market excess, even after consideration of idle capacity and transfer of services supplied to dental therapists, provides a marked contrast to many, but not all, developed countries. It also offers an opportunity to shape occupational and specialty distribution to the advantage of dental professions and the public. 相似文献
67.
S. Anil MDS V. T. Beena MDS † Ravindran Ankathil MSc PhD ‡ P. Remani MSc PhD § T. Vijayakumar MSc PhD ¶ 《Australian dental journal》1995,40(1):39-42
A case of mandibulofacial dysostosis (Treacher Collins syndrome) is presented. Clinical features and skull radiographs revealed typical anomalies associated with the syndrome. Cleft of the soft palate and unerupted multiple supernumerary teeth were present in this case. No haematological, biochemical or immunological abnormalities could be detected in the patient. Pedigree analysis showed an autosomal dominant mode of transmission of the disease. Chromosomal studies did not reveal any structural or numerical discrepancies. 相似文献
68.
Terminology of facial morphology in the vertical dimension 总被引:1,自引:0,他引:1
A. R. Collett BSc MDSc PhD V. C. West DDO DOrth BSc MDSc LLB FRACDS † 《Australian dental journal》1993,38(3):204-209
Consideration of facial type plays an important role in the formulation of an orthodontic treatment plan and prognosis of treatment. Of particular importance is the vertical relationship, that is, whether an individual is long-faced (dolichofacial), or short-faced (brachyfacial). The vertical facial type provides a clue regarding the growth direction of the facial complex, and should be used with an anteroposterior classification to describe a patient's face. The potential for confusion in communicating vertical facial types exists due to the nature of the terminology in use. For example, the term dolichoprosopic as used in the Bimler analysis has an opposite meaning to the term dolichofacial. It would seem prudent that if such terminology is to be employed there should be some attempt at standardization, and at least an appreciation of the derivations of the terms, and their differences. 相似文献
69.
A case of maxillary ameloblastoma is presented. A non-healing, asymptomatic ulcerative lesion in the maxillary tuberosity region did not respond following relief of physical irritation. The clinical appearance of the lesion was compatible with that of a malignant tumour, but the histopathology was consistent with a diagnosis of ameloblastoma of the maxilla. 相似文献
70.
Rain Papli BDS MSc MDSc Jenny M. Lewis BSc GradDipRecreation Planning MEnvSc 《Australian dental journal》1989,34(1):60-68
Refractory chronic periodontitis of 16 patients was treated by root planing and adjunctive tetracycline hydrochloride therapy. The antibiotic was taken orally one hour before root planing and continued for six days at a dosage of 250 mg six hourly. The clinical data for each patient were recorded as the number of probing depths in each of the 1-3 mm, 4-6 mm and 7-10 mm ranges. The Multivariate Analysis of Variance (MANOVA) procedure for repeated measurements was used to analyse the data. The results demonstrated that the number of sites with probing depths of 4-6 mm and 7-10 mm associated with incisors, canines, premolars and molars decreased with a corresponding increase in the number of sites in the 1-3 mm range. Incisor and canine teeth showed a better response to treatment than premolars, which responded better than molars. The cases were followed for varying periods of time from six months to two years following antibiotic therapy. The probing depth reduction achieved following root planing and tetracycline hydrochloride therapy was maintained during this review period. 相似文献