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991.
目的比较超声、Er,Cr:YSGG激光及Er:YAG激光辅助1%次氯酸钠(NaOCl)溶液冲洗对人离体牙根管表面粪肠球菌生物膜及根尖区不同深度牙本质小管内粪肠球菌的杀灭效果。
方法单直根管下颌前磨牙42颗,建立粪肠球菌生物膜感染的根管模型,采用随机字表法随机抽取2颗确定建成粪肠球菌生物膜感染根管模型,剩余40颗牙采用随机数字表法按随机对照原则分为5组,每组8颗。A组:5.25% NaOCl联合17%乙二胺四乙酸(EDTA)注射器冲洗;B组:0.9%氯化钠溶液注射器冲洗;C组:1% NaOCl溶液超声荡洗;D组:1% NaOCl溶液Er:YAG激光活化冲洗;E组:1% NaOCl溶液Er,Cr:YSGG激光活化冲洗。按分组进行处理后取样菌落计数,计算灭菌率。使用SPSS 17.0统计软件对实验数据进行方差齐性及正态性检验比较各组间和组内的灭菌率。
结果(1)组间比较:对根管壁表面,各组冲洗方法灭菌率比较,B组(5.74%)相似文献
992.
993.
Ying Liang Fang Xie Xinyuan Tang Mei Wang Enmin Zhang Zhikai Zhang Hong Cai Yanhua Wang Xiaona Shen Hongqun Zhao Dongzheng Yu Lianxu Xia Rong Hai 《The American journal of tropical medicine and hygiene》2014,91(4):722-728
The Yersinia pestis chromosome contains a large variety and number of insert sequences that have resulted in frequent chromosome rearrangement events. To identify the chromosomal rearrangement features of Y. pestis strains from five typical plague foci in China and study spontaneous DNA rearrangements potentially stabilized in certain lineages of Y. pestis genomes, we examined the linking mode of locally collinear blocks (LCBs) in 30 Y. pestis strains by a polymerase chain reaction-based method. Our results suggest most strains have relatively stable chromosomal arrangement patterns, and these rearrangement characteristics also have a very close relationship with the geographical origin. In addition, some LCB linking modes are only present in specific strains. We conclude Y. pestis chromosome rearrangement patterns may reflect the genetic features of specific geographical areas and can be applied to distinguish Y. pestis isolates; furthermore, most of the rearrangement events are stable in certain lineages of Y. pestis genomes. 相似文献
994.
995.
Linyuan Wang Cynthia T. Luk Stephanie A. Schroer Alannah M. Smith Xie Li Erica P. Cai Herbert Gaisano Patrick E. MacDonald Zhenyue Hao Tak W. Mak Minna Woo 《Diabetologia》2014,57(9):1889-1898
Aims/hypothesis
Diabetes mellitus represents a significant burden on the health of the global population. Both type 1 and type 2 diabetes share a common feature of a reduction in functional beta cell mass. A newly discovered ubiquitination molecule HECT, UBA and WWE domain containing 1, E3 ubiquitin protein ligase (HUWE1 [also known as MULE or ARF-BP1]) is a critical regulator of p53-dependent apoptosis. However, its role in islet homeostasis is not entirely clear.Methods
We generated mice with pancreas-specific deletion of Huwe1 using a Cre-loxP recombination system driven by the Pdx1 promoter (Pdx1cre + Huwe1 fl/fl) to assess the in vivo role of HUWE1 in the pancreas.Results
Targeted deletion of Huwe1 in the pancreas preferentially activated p53-mediated beta cell apoptosis, leading to reduced beta cell mass and diminished insulin exocytosis. These defects were aggravated by ageing, with progressive further decline in insulin secretion and glucose homeostasis in older mice. Intriguingly, Huwe1 deletion provided protection against genotoxicity, such that Pdx1cre + Huwe1 fl/fl mice were resistant to multiple-low-dose-streptozotocin-induced beta cell apoptosis and diabetes.Conclusion/interpretation
HUWE1 expression in the pancreas is essential in determining beta cell mass. Furthermore, HUWE1 demonstrated divergent roles in regulating beta cell apoptosis depending on physiological or genotoxic conditions. 相似文献996.
997.
Polyurethane modified with polylactic acid microcapsules were fabricated for controlled release of chlorpyrifos (one of the high usage solid phosphorous insecticides) via interfacial polymerisation with diphenylmethane diisocyanate, polyether triol, 1,4-butanediol and polylactic acid as modifier. The structure, morphology and release properties of synthesised microcapsules were characterised by Fourier transform infra-red spectroscopy, thermogravimetric analyser, scanning electron microscope, particle size analyser and high-performance liquid chromatography. More benign solvents, namely ethyl acetate and n-butyl acetate were used as replacement for toxic solvents commonly used in the preparation of polyurethane microcapsules, namely xylene. The spherical microcapsules prepared in this study were 1–20?μm in diameter. Fourier transform infra-red spectroscopy indicated that polylactic acid had successfully participated in the interfacial polymerisation of polyurethane. Encapsulation efficiency of microcapsules can amount up to 71.0% w/w with a loading efficiency of 26.2% w/w. The microcapsules exhibited a sustained release period above 60?days. Combining polylactic acid into the soft segment of polyurethane proves to effectively accelerate the release rate. 相似文献
998.
999.
Polymorphism analysis of Glutathione S-transferase A1 in patients with hematological diseases and its effect on GST enzyme activity 下载免费PDF全文
Glutathione S-transferases (GSTs) are important drug-metabolizing enzymes that catalyze the binding of glutathione (GSH) to electrophilic substances. GST has genetic polymorphism, and the enzyme activity of GST affects the metabolism of certain drugs in vivo. In the present day, we investigated the GST enzyme activity and GSTA1 gene polymorphism in 170 patients with hematological diseases and explored their relationship. The GSTA1 gene polymorphism of the patient was analyzed by PCR- restriction fragment length polymorphism (PCR-RFLP) technique, and the base sequences of the four mutation sites (-631, -567, -69, and -52) in the promoter region were determined by DNA-Sequencer. The patient's GST enzyme activity was calculated by measuring the rate at which it catalyzed the reaction between 1-chloro-2,4-dinitrobenzene (CDNB) and GSH. The average GST enzyme activities of males and females were 5.20±0.13 and 5.17±0.12 nmol/min/mL, respectively, and the difference was not significant (P = 0.91). The frequencies of genotypes GSTA1*A*A (wild genotype), GSTA1*A*B (heterozygous genotype), and GSTA1*B*B (homozygous mutant genotype) were 75.3%, 22.9%, and 1.8%, respectively. Alleles GSTA1*A and *B were distributed at 86.8% and 13.2%, respectively. The genotype frequency distribution between males and females was no significant difference by Pearson’s chi-square test (P = 0.743). The average GST activity of the heterozygous mutant genotype (4.83±0.76 nmol/min/mL) was lower than the wild genotype (5.34±1.26 nmol/min/mL, P = 0.018), and higher than that of the homozygous mutant genotype (3.32±0.07 nmol/min/mL, P = 0.022). These findings might help us improve the individualized treatment of patients with hematological diseases in the future and promote the development of precision medicine for blood diseases. 相似文献
1000.