地果(Ficus tikoua Bur.)抗菌作用检测

采用琼脂平板扩散法,从定量的角度检测了地果(FicustikouaBur.)水煎剂对G-大肠杆菌、志贺氏痢疾杆菌、G+金黄色葡萄球菌的抑菌作用。结果表明,地果水煎剂对G-志贺氏痢疾杆菌、G+金黄色葡萄球菌有明显的抑菌作用,且抑菌作用强度与药液浓度成正相关;对G-大肠杆菌无抑菌作用。

A Sectioning Technique for Extraction of Impacted Third Molar by Using a Straight Handpiece and Carbide Bur: Case Report

Extraction of the lower third molar is one of the most common procedures performed in oral surgery. In general, impacted tooth extraction involves sectioning the tooth’s crown and roots. In order to divide the impacted tooth so that it can be extracted, high-speed air turbine drills are frequently used. However, complications related to air turbine drills may occur. In this report, we propose an alternative tooth sectioning method that obviates the need for air turbine drill use by using a low-speed straight handpiece and carbide bur. A 21-year-old female patient presented to the institute’s dental hospital complaining of symptoms localized to the left lower third molar tooth that were suggestive of impaction. After physical examination, tooth extraction of the impacted left lower third molar was proposed and the patient consented to the procedure. The crown was divided using a conventional straight low-speed handpiece and carbide bur. This carbide bur can easily cut through the enamel of crown. On post-operative day number five, suture was removed and the wound was extremely clear. This technique could minimise intra-operative time and reduce the morbidity associated with air turbine drill assisted lower third molar extraction.

A comparative evaluation of dentin caries removal with polymer bur and conventional burs—An <i>in vitro</i>study

Aim: To evaluate the comparative efficacy of Polymer bur (Smartprep) and Conventional burs (Carbide bur & Diamond Points) in selective Dentin caries removal. Materials and method: 15 freshly extracted carious human premolars and molars were selected for this study. These teeth were split in the center of carious lesion, in order to obtain two corresponding half. Thus 30 samples were prepared in this way. These were randomly divided in to 3 groups of 10 samples each. Group 1: The carious portion of these samples was excavated with the help of polymer bur Smartprep (SS White). Group 3: Prepared with Tungsten carbide round bur (No. 018). Group 3: Prepared with the help of Diamond points (No. 018). The period of time involved in this process is measured. After excavation of all carious lesions, a longitudinal section from mid most part of lesion was obtain with the help of diamond disc at slow speed. After staining with caries detector dye “Seek”, the sections were subjected to histological evaluation under stereomicro-scope. The thickness of remaining caries is measured in more or less than 1 mm. Results: The difference in grading of remaining carious dentin between Polymer bur and Conventional burs were statistically non- significant, but Polymer bur taken more time in comparison to Conventional burs. Conclusion: Smartprep bur is more conservative in selectively dentin caries removal than Conventional burs but same time it is more time consuming than Conventional burs.

An Assessment of Burs Designed to Cut Zirconia

Objective: Zirconia is increasingly being used in restorative dentistry but its removal is often a difficult procedure due to its resistance to cutting with conventional diamond burs. Zirconia cutting burs have been developed and this study aims to compare 4 such burs. Methods: 35 experienced restorative dentists selected from our Practice Based Network (PBN) were asked to evaluate the cutting of a 1 mm groove into zirconia using 4 burs A (Meisinger), B (ZR2-1 experimental bur from DIATECH), C (Komet) & D (DIATECH Z-Rex, a bur designed with enhanced bonding of diamond grit to bur shank). Responses regarding cutting time, performance and wear were recorded. Results: For best cutting times and also overall performance D performed best and C the worst, with little difference between burs A and B. Bur C also performed least well for wear on the bur. Conclusion: The newly designed zirconia cutting bur DIATECH Z-Rex with enhanced bonding of diamond grit performed best in the analysis by the 35 dentists.

Scale Breeding and Reproduction Technique of Ficus tikoua Bur.Container Seedlings

Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the environment and fast growth and reproduction.Using non-woven bag as a breeding container for seedlings,the scale breeding and reproduction technique of F.tikoua container seedlings was summarized through the important links of seedling bed construction,seedling collection,soil configuration,container selection,cutting cultivation,field management,and disease and pest control.This technique can achieve differential,massive and sustainable efficient breeding and reproduction of F.tikoua seedlings in a short time.

Er:YAG激光和传统车针去龋后牙本质粘接强度的比较

目的:比较使用不同模式Er:YAG激光以及传统车针去龋后牙本质与复合树脂的粘接强度。方法:选用人类离体磨牙模拟龋坏,分别采用Er:YAG激光中短脉冲(medium short pulse,MSP)模式、Er:YAG激光超短脉冲(super short pulse,SSP)模式和传统车针去除模拟的龋坏后,采用自酸蚀粘接剂将牙体标本与复合树脂粘接制成试件。使用万能试验机对试件进行拉伸试验,测得断裂负荷和粘接强度,并采用单因素方差分析和Tukey多重比较进行统计学分析。采用扫描电子显微镜观察3种不同去龋方式处理后的牙本质表面形态,以及涂布自酸蚀粘接剂并固化后试件的横截面形态。结果:使用Er:YAG激光MSP模式处理后牙本质与复合树脂的粘接强度最高,SSP模式处理后次之,传统车针处理后最低,但差异无统计学意义(P>0.05)。扫描电子显微镜图像显示,Er:YAG激光MSP模式处理后的牙本质表面较平坦,牙本质小管内几乎没有残屑;Er:YAG激光SSP模式处理后的牙本质表面呈现鳞片状,牙本质小管内可见少量碎屑;而传统车针处理后牙本质小管大部分处于被表面牙本质部分甚至完全遮盖的状态,牙本质小管内充满残屑。结论:使用Er:YAG激光去龋相比传统车针去龋可以获得较好的牙本质粘接强度,且对牙本质小管的处理深度和洁净度明显优于传统车针去龋,其中MSP模式更佳。

Osteotomy Protocol for Implant Insertion of One Day Biotech: One Drill, One Implant

Background: Four factors determine the quality of an implantology kit: 1) Heat generated by the drills;2) Morphology of the osteotomy according to the diameter of the implant;3) Efficiency of collecting autologous bone;and 4) Osteotomy execution time. Materials and Methods: This article examines the heat produced by drills during osteotomy, focusing on the effect of the following factors: drilling technique;volume of autologous bone harvested;drilling time;implant primary stability;and the percentage of osseointegrated implants after primary healing. Discussion: The four factors mentioned above are analyzed based on the data obtained for sequential, biological, and One Drill milling techniques. Conclusions: 1) One Drill is the fastest technique for performing the osteotomy;2) All techniques stay within the biological temperature range of living bone, with the lowest increase in temperature achieved using One Drill with irrigation;3) The bone harvested showed no statistically significant differences between biological milling and the One Drill technique, both far superior to the sequential technique;and 4) There is no statistically significant difference in the number of osseointegrated implants among the three techniques analyzed.

拔牙时车针断入软腭内1例报告并文献复习

高速涡轮手机联合外科专用切割车针拔除阻生牙时,器械分离发生较为少见,而断针断入软腭内则更为罕见。本文报告1例拔牙时车针断入软腭内的罕见病例,断针在影像学及三维可视化技术辅助定位下,局麻下顺利取出。结合文献复习,总结该并发症发生的原因以及相应的处理方式,探讨如何减少该并发症的发生。

宽厚板支承辊辊身硬度问题分析与预防

整理分析43支宽厚板支承辊差温热处理一次回火硬度的分布,合格数量仅占81%,经过补充回火后全部合格,但未彻底消除硬度异常现象。结合具体案例,分析产生硬度异常的原因,提出预防硬度异常的优化措施,降低回火成本,提升宽厚板支承辊整体硬度的均匀性。

地瓜藤提取物的活性成分研究

研究地瓜藤(Ficus tikoua Bur.)提取物的活性成分,经初步提纯后得到3个含量较多的组分,分别对其进行抗氧化和抗菌试验。结果表明,C组分对DPPH自由基、羟基自由基以及超氧阴离子自由基的清除率均比A、B组分的要高,且随着浓度的增加,各组分的清除率均呈上升的趋势。C组分对大肠杆菌、表皮葡萄球菌、志贺杆菌、金黄色葡萄球菌的抑制作用比A和B组分强,且3种组分的抑菌作用均随浓度的增加而增加。A、B、C 3种组分的MIC分别为1.03、1.04、0.51 mg/m L。

板栗(Castanea mollissimaB1.)空苞形成因子的研究——Ⅱ.板栗空苞的胚胎学

选连续三年发生空苞率达90%的树为材科,对其胚眙发育进程进行了观察,并与连续三年不发生空苞树作比较。结果表明:板栗空苞发生的原因在胚胎学上有如下几方面,大孢子母细胞发育停止,减数分裂不能正常进行;成熟胚囊结构异常,卵细胞、助细胞解体;传粉受精不良导致受精作用异常;原胚早期敗育、胚乳败育、胚发育中止及部分空苞中种子的子叶不发育等?鄄熘谢狗⑾?总苞及子房外形的大小与胚珠发育进程之间有密切关系;另在珠形胚时期,一个子房内发育胚珠与退化胚珠在外形大小上也有明显差別。

樱草杜鹃中的黄酮类化合物(英文)

从樱草杜鹃(Rhododendron primulaeflorum)地上部分的乙醇提取物中分离得到10个黄酮类化合物,经理化性质及波谱分析,鉴定为杜鹃素(1)、4′,5,7-三羟基-8-甲基黄烷酮(2)、二氢山柰酚(3)、异鼠李素(4)、槲皮素(5)、陆地棉苷(6)、瑞诺苷(7)、(2R,3R)-花旗松素-3-O-α-L-吡喃阿拉伯糖苷(8)、(2R,3S)-花旗松素-3-O-α-L-吡喃阿拉伯糖苷(9)、(2S,3R)-花旗松素-3-O-α-L-吡喃阿拉伯糖苷(10)。所有化合物均为首次从该植物中分得。

地板藤根的化学成分研究

目的研究采自云南省楚雄州地板藤根的化学成分。方法对地板藤根95%乙醇提取物的石油醚和乙酸乙酯萃取部分采用硅胶柱色谱、Sephadex LH-20柱色谱等方法分离纯化;根据波谱学数据和理化性质进行结构鉴定。结果从地板藤根的石油醚和乙酸乙酯萃取部分分离得到13个化合物,主要为黄酮类、三萜类及甾体类化合物,分别鉴定为5α-豆甾-3,6-二酮(1),3β-羟基豆甾-5-烯-7-酮(2),β-谷甾醇(3),β-香树脂醇(4),齐墩果酸(5),α-香树脂醇乙酸酯(6),3-O-乙酰基齐墩果酸(7),槲皮素(8),芹菜素(9),木犀草素(10),(2R,3R)-(+)-二氢槲皮素(11),北美圣草素(12),柚皮素(13)。结论除化合物3,4,5,6及9外,其余化合物均为首次从该植物中分离得到。

拉延-翻孔复合成形规律及其控制

从变形力学方面对轴对称带孔板坯的拉延翻孔复合成形规律进行了较深入的理论分析 ;为在拉延翻孔复合成形过程中 ,如何采取必要的工艺措施 ,对成形过程实行有效控制 ,提供了理论依据。

板栗(Castanea millissimaB1.)空苞形成因子的研究——Ⅰ.授粉受精对板栗空苞形成的影响

板栗空苞率高是其低产的重要原因之一。本研究通过人工授粉、剪除雌花柱头等试验发现:板栗不经授扮,座苞率高达68%以上;授粉受精不良不是板栗落果的主要原因,但不经授粉所结果球全为空苞。如选择亲和力强的花粉授扮,可以大大减少空苞;自花授粉者空苞率较高(平均高达18.3%),以混合花粉授粉,不仅空苞率很低(平均为0.4%),而且总苞内的果实数显著高于自花授扮。上述结果说明,授粉受精不良是板栗形成空苞的主要原因之一。

推靠式旋转导向钻具力学性能研究

旋转导向钻井系统在大位移井中得到广泛的应用 ,该项技术国内正处于研究阶段。结合国家 86 3项目“旋转导向钻井系统整体方案设计及关键技术研究” ,对设计出的偏置式旋转导向钻具组合进行了力学性能的理论研究 ,介绍了理论模型的建立和力学性能研究的部分结果 ,给出了推靠式旋转导向钻具的受力状态分析、井眼曲率预测、导向稳定器运行参数、井眼曲率和方向与导向稳定器偏心距和偏心方向的关系。可以为旋转导向稳定器的设计提供理论依据。

地板藤根的抗氧化和抑菌活性研究

采用DPPH法测定地板藤根提取物及其不同溶剂萃取物的抗氧化活性,用微生物纸片法测定其乙醇提取物的抑菌活性.结果表明:地板藤根乙醇提取物及其乙酸乙酯和正丁醇萃取物对DPPH自由基(DPPH.)有较强的清除能力,并且这种清除作用随其质量浓度的增大而增加.地板藤根乙醇提取物及其乙酸乙酯和正丁醇萃取物清除DPPH.的半数有效量(EC50)分别为0.004 6、0.004 7、0.006 4 mg/mL.抑菌实验显示地板藤根乙醇提取物有弱的抑菌活性.

牙科手机传播乙型肝炎可能性的动物实验研究

目的用鸭乙型肝炎病毒(DHBV)血清污染牙科手机,观察污染剂量在斑点杂交方法检不出的情况下,是否具有对动物的感染性。方法用强阳性鸭肝炎病毒污染的牙科手机,将手机洗脱液一部分运用斑点杂交法对残留病毒DHBV-DNA进行检测作为体外实验;另一部分转染1d龄北京鸭,10d后取血检测DHBV-DNA复制情况作为体内实验。结果体外实验检测结果均呈现阴性,OD值最大为0.422,而体内实验的检测结果发现所有鸭子体内均有不同程度的DHBV-DNA复制,OD值最大达到0.861。结论即使DHBV污染的牙科手机在斑点杂交检测为阴性结果的情况下,也不能排除传播肝炎病毒的可能。

柘树根多糖的分离纯化及结构表征

以柘树[Cudrania tricuspidata(Carr.)Bur.]的根为材料,经热水抽提、木瓜蛋白酶-Sevag法除蛋白、乙醇沉淀和DEAE-Sephadex A-50凝胶柱层析分离纯化,得到一种水溶性的柘树根多糖(CPS-0).采用HPLC、糖基组成分析、甲基化分析、GC、GC-MS、NMR(1H NMR,13C NMR及HMQC)、元素分析、UV和IR等技术对CPS-0的纯度、性质、组成和结构进行表征.结果表明,CPS-0仅含葡萄糖,分子量为4·6×103,主链由1,4-连接的α-D-葡萄糖残基组成,其侧链由末端及1,4-连接的葡萄糖残基构成,取代于主链分支点葡萄糖的6位,平均每10个葡萄糖残基组成的重复单元中含有1个分支.