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991.
AIM: To report the multidisciplinary care of an unaesthetic geminated maxillary lateral incisor tooth, which allowed its preservation in the mouth. SUMMARY: Preoperative examination of an unsightly geminated maxillary lateral incisor (tooth 22) demonstrated two pulp chambers and open apices, with normal pulp sensitivity responses. At surgery, a periodontal mucoperiosteal flap was reflected and the distal part of the geminated tooth was removed. The exposed root canal of the preserved tooth was sealed with mineral trioxide aggregate (MTA). The extraction socket and osseous defect was grafted with decalcified freeze-dried bone allograft (DFDBA) before flap closure. During follow-up, distal caries in tooth 22 and a diastema between tooth 22 and 23 were managed with composite resin restorations. Forty-two months postoperatively, normal thermal and electrical pulp sensitivity tests confirmed pulp health. Convincing apexogenesis and dentinogenesis of the developing root was confirmed by radiographic examination. Acceptable periodontal health including 3-4 mm clinical probing depths was achieved. Optimizing aesthetics and occlusion was accomplished without orthodontic treatment.  相似文献   
992.
化学发光显影法检查药物中的砷   总被引:2,自引:0,他引:2  
将鲁米诺-过氧化氢体系被Cr催化产生的光学发光记录在X光胶片上,通过比较由标准和样品形成影斑深浅,进行药物中砷的限量检测新方法。该法灵敏、简便,测定结果可长期保存,特别适用于药物中砷的限量检测。  相似文献   
993.
胡俊丽  张月飞  黄雪琴 《癌症进展》2012,10(1):69-72,79
目的 研究亚砷酸( As2O3)诱导鼻咽癌(nasopharyngeal carcinoma,NPC)CNE- 2Z细胞株中抑癌基因p16的表达.方法 体外培养的CNE-2Z细胞分别加入不同浓度的亚砷酸,并作用于不同时间.用终浓度为2μmol/L、1 μmol/L、0.5μmol/L的As2O3加入鼻咽癌CNE-2...  相似文献   
994.
目的:探讨亚砷酸(arsenic trioxide,ATO)在治疗JAK2V617F突变阳性的骨髓增殖性疾病(myelopro-liferative neoplasm,MPN)中的作用。方法:选取20例JAK2V617F阳性的MPN患者用亚砷酸治疗,观察其治疗前后不同时期相应的血象变化以及JAK2V617F表达,并与单用羟基脲的对照组作比较。结果:与对照组相比,3个月及1年后,应用亚砷酸治疗组的红细胞、血红蛋白、血小板、白细胞均明显降低(P<0.01);治疗3年后两组上述指标无明显差异(P>0.05);JAK2V617F的转阴率两组无明显差异性(P>0.05)。结论:亚砷酸作为一种诱导凋亡剂短期内可以有效地降低三系血细胞,但未有证据表明能降低MPN患者JAK2V617F的阳性表达,故长期疗效需更多的临床及实验观察。  相似文献   
995.
The aim of this study was to present the treatment and long-term follow-up of a case in which white mineral trioxide aggregate (WMTA) was used in the pulpectomy of a non-vital primary molar with no permanent successor.
The physiological, aesthetic and functional consequences of treating primary teeth without permanent successors makes this a unique challenge. In the present case, WMTA was used in the pulpectomy of a primary molar with no permanent successor in an 8-year-old child. The treatment was considered successful. Follow-up examinations showed that root resorption in the mesial root surface, with no infra-occlusion or ankylosis 36 months after treatment.
WMTA may be considered as an alternative pulpectomy material for non-vital primary teeth with no permanent successors, although long-term clinical studies are still needed.  相似文献   
996.
997.

Objective

Arsenic trioxide (As2O3) has been used as an anticancer agent in traditional Chinese medicine for thousand years and berberine is an isoquinoline alkaloid present that has indicated significant antimicrobial activity. We have examined the combined anticancer effects of As2O3 and berberine against the human neuroblastoma (HNB) SH-SY5Y cells in vitro, and to elucidate underlying molecular mechanism.

Methods

HNB SH-SY5Y cells were treated with 2 µM As2O3 and 75 µg/ml berberine, and their survival, cell death mechanism as well as synergistic cytotoxic effects were estimated by using MTT assay, DAPI staining, agarose gel electrophoresis, flow cytometric analysis, and western blot analysis.

Results

The combined treatment of two drugs also markedly decreased cell viability. The cytotoxic effects of two drugs were revealed as apoptosis characterized by chromatin condensation, DNA fragmentation, and the loss of mitochondrial membrane potential. The apoptotic cytotoxicity was accompanied by activation of caspase-3 protease as well as decreased the expression of Bcl-2, Bid, and Bcl-x/L. In addition, the cells treated with combination of two drugs also showed significantly increased intracellular reactive oxygen species levels and lipid peroxidation compared to cells As2O3 or berberine only.

Conclusion

Combined treatment of As2O3 with berberine induced activation of apoptotic signaling pathways in HNB SH-SY5Y cells. These results suggest that the possibility of the combined treatment of two chemotherapeutic agents with low concentration improving cytotoxic effect for cancer cells with minimal side effects.  相似文献   
998.

Introduction

The incorporation of light-curable resins has been proposed for mineral trioxide aggregate (MTA) to improve its properties and reduce its setting time. The aim of the present study was to assess the pH and calcium ion release of an experimental bisphenol A ethoxylate dimethacrylate/MTA-based root-end filling material (E-MTA) in comparison with white MTA Angelus (Angelus, Londrina, PR, Brazil) (W-MTA) and to evaluate the influence of the addition of calcium chloride (CaCl2) on these properties.

Methods

Polyethylene tubes filled with the materials were immersed in deionized water for the measurement of pH (digital pH meter) and calcium release (atomic absorption spectrophotometry). The evaluations were performed at 3 and 24 hours and 7, 15, and 30 days. Data were measured using 2-way repeated measures of variance followed by the Holm-Sidak method (P < .05).

Results

All materials presented a reduction in the pH and released calcium ions during the 30 days of the study. E-MTA showed a significantly lower calcium ion release capacity when compared with W-MTA (P < .05). The calcium release of E-MTA + 5% CaCl2 was similar to W-MTA (P > .05).

Conclusions

The monomer bisphenol A ethoxylate dimethacrylate added to MTA formed a material with a lower capacity of calcium release than W-MTA despite maintaining a similar pH. However, the addition of CaCl2 improved the calcium release of this material.  相似文献   
999.
砷剂诱导人胃癌细胞株凋亡及对C-myc基因作用的研究   总被引:2,自引:0,他引:2  
目的研究砷剂(As2O3)对人胃癌细胞的诱导凋亡作用及对C-myc基因表达的影响。方法选用人胃癌BGC-823细胞株,运用体外细胞培养法、MTT法、流式细胞术检测As2O3对人胃癌的诱导凋亡作用;用逆转录-聚合酶链反应(RT-PCR)方法检测C-mycmRNA的表达。结果As2O3对人胃癌BGC-823细胞具有抑制作用,其抑制率呈时间-剂量依赖关系。不同浓度的As2O3均可诱导凋亡。1.0μmol/L、3.0μmol/L的As2O3可下调C-myc的表达。结论As203具有抗肿瘤作用,主要是通过诱导细胞凋亡实现。其机制与下调C-myc表达有密切关系。  相似文献   
1000.
目的 观察正常人摄人紫菜后,尿中不同形态砷化物随时间的排泄规律.方法 收集24名受试者(14名男性,10名女性)食人紫菜后72 h内不同时点的尿液,采用高效液相色谱.氢化物发生.原子荧光分光光度法(HPLC-HG-APS)检测尿中砷代谢产物的形态与浓度.结果 在食用紫菜后72 h内,与食用紫菜前比较,男性除第1和48 h外,尿中iAs浓度均显著增高(P<0.05);除第1和12 h外,尿中一甲基胂酸(MMA)浓度显著增高(P<0.05);第1~72 h尿中二甲基胂酸(DMA)浓度显著增高(P<0.05);女性受试者食用紫菜后,除第3、5和48 h外,尿中iAs浓度明显增高(P<0.05);除第5和12 h,尿中MMA浓度均显著增高(P<0.05);第1~72 h尿中DMA浓度均有显著增高(P<0.05).食用紫菜后,女性尿中DMA浓度显著高于男性.结论 摄入相同剂量紫菜后女性尿中DMA浓度显著高于男性,并且DMA浓度随时问先升高后降低.
Abstract:
Objective To know the effects of laver intake on arsenic species in urine of people, and investigate the characteristics of arsenic metabolism. Methods The urine samples were collected from 24 subjects who had laver available on markets, arsenic species in urine samples were detected with hydride generation atomic fluorescence spectroscopy. Results There was a significant increase of urinary iAs seventy-two hours after laver intake except one and forty-eight hours, increase of MMA seventy-two hours after laver intake except one and twelve hours, and increase of DMA from the first hour to the 72nd hour in male group. There was a significant increase in the urinary iAs seventy-two hours after laver intake except three, five and forty-eight hours, increase of MMA seventy-two hours after laver intake except five and twelve hours, increase of DMA from one to seventy-two hours after laver intake in female group. Conclusion The urinary concentration of DMA is significantly higher in female group compared with male group after laver intake in the same weight and urinary DMA increases in the beginning, after that decreases gradually.  相似文献   
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