白蛋白微球经颈外动脉灌注后的体内分布及降解速度

目的 :探讨作为药物载体的白蛋白微球 (AMS)经颈外动脉灌注后在体内的分布及降解速度 ,以及栓塞血管再通时间 ,为AMS的安全性提供依据。方法 :经家兔颈外动脉灌注以12 5 I标记的平均粒径 56.3 μm的白蛋白微球后 ,测定局部组织及全身脏器内的放射剂量。用 760ml/L的泛影葡胺行家犬颈外动脉造影观察AMS灌注后末梢血管再通时间。结果 :微球经颈外动脉灌注后 92 .2 3 %集中于头颈局部组织内。微球对颈外动脉的微小分枝有明显的栓塞作用 ,栓塞的血管在 7～ 9d内再通。结论 :AMS可作为药物的缓释载体     

口腔肿瘤患者手术后早期应用肠内营养的临床观察

目的观察口腔肿瘤手术后早期应用肠内营养对患者营养状况的影响。方法选择口腔肿瘤患者60例,随机分为早期肠内营养(earlyenteralnutrition,EEN)组和传统肠内营养(traditionenteralnutrition,TEN)组,每组30例。EEN组手术后12~16h给予能全力行营养支持,TEN组于肠道排气后经口进食。分别测定术前及术后营养相关指标。结果EEN组术后住院天数及术后8d体质量、氮平衡、血浆白蛋白、前白蛋白、视黄醇结合蛋白和淋巴细胞总数等均明显优于TEN(P<0.05)。结论口腔肿瘤患者手术后早期应用肠内营养,能较好的满足患者的营养需求,可改善术后营养状况。     

我国口腔正畸学科的发展现状、存在问题和解决对策

我国口腔正畸学作为口腔医学的一个分支学科 ,已有 5 0多年的历史。为了促使口腔正畸事业健康发展 ,在看到进步的同时 ,还必须要重视存在的问题并且提出解决的对策。一、发展现状上世纪 80年代以来 ,我国口腔正畸学科经历了一个快速发展期。首先是随着人民文化、经济水平的不断提高 ,人们对口腔正畸的认识和需求大大提高了。把矫正牙齿作为一种追求健康美观 ,体现文化素质的时尚。现在 ,我国每年大约有超过 30万人接受正畸治疗 ,当然其中绝大部分是青少年学生 ,但成年人矫正的比例也不断上升。因此 ,应该说目前我国口腔正畸的快速发展是客观…     

Evidence of chemisorption of maleic acid to enamel and hydroxyapatite

Maleic acid has been used as an etchant or non-rinse conditioner in adhesive dentistry. However, the inherent mechanisms of the interaction of maleic acid with hydroxyapatite/enamel have never been fully elucidated. The purpose of this study was to provide evidence for the chemisorption of maleic acid onto hydroxyapatite/enamel, and to identify the reaction products obtained following the interaction of maleic acid with hydroxyapatite. Hydroxyapatite particles were dissolved in a 15% (w/v) aqueous solution of maleic acid (pH = 0.98). Half of the solution was dried to obtain a desiccated mixture. This mixture, hydroxyapatite, maleic acid and self-prepared calcium maleate were analysed by X-ray diffraction (XRD). Acetone was added to the other half of the solution to obtain a precipitate. This precipitate, hydroxyapatite, maleic acid, unetched enamel and maleic acid-etched enamel were analysed by X-ray photoelectron spectroscopy (XPS). The precipitate was also analysed by (1)H NMR. A new binding energy, indicating carboxylate groups, was detected by XPS on the precipitate and maleic acid-etched enamel surface. XRD data indicated the formation of calcium maleate and calcium hydrogen phosphate after the reaction. NMR data revealed that one carboxylic group of maleic acid reacted with hydroxyapatite. Hence, maleic acid can chemisorb to hydroxyapatite and enamel via ionic interactions.     

颌面、咽腔气道形态与颈椎姿势的相关性分析

目的：研究颌面及咽腔气道形态、位置与颈椎姿势的相关性。方法：随机选取81名16－26岁的年轻人，男性44名，女性37名，拍摄自然头位生，进行头影测量分析并对33项测量数据进行统计，分析。结果：（1）男女性别在头位变量上无显著差异；（2）SNA，SNB，SN／MP、N－S－PNS，NSU，NSGn,ANS-PNS-Gn,NSH等变量与头位变量间有显著的相关性。（3）相对于FH／VER，OPT／VER，CVT／VER面部形态结构与FH／OPT、FH／CVT相关性较大；（4）在面部结构与FH／OPT、FH／CVT的相关性上，下颌骨大于上颌骨，矢状向大于垂直向，相对于“S”点大于相对于“N”点。结论：颈核姿势与咽腔气道，以及与咽腔气道形态和位置有密切关系的颌骨位置呈较明显的相关性，颌面形态通过改变咽腔气道的位置及形态而与一定的颈椎姿势相联系。     

TGF-β3作用下人牙髓细胞内Smad2、Smad3蛋白表达水平的变化

目的：探讨TGF—B3对人牙髓细胞内Smad2、Smad3蛋白表达的调控作用和差异。方法：取生长良好的第5代人牙髓细胞，分为实验组和对照组，实验组用5ng／mL TGF—β3刺激并培养6、12、24、48h，对照组不予刺激。提取各组总蛋白质，分别用Smad2、Smad3抗体进行Western印迹杂交。结果：与对照组相比，Smad3在TGF—β3刺激后6h、12h，其蛋白表达量无明显变化，而在刺激后24h表达量明显下降，刺激48h后表达十分微弱；Smad2在对照组以及刺激后各时间组，其蛋白表达量无显著变化。结论：人牙髓细胞内存在Smad2、Smad3蛋白的表达，TGF—β3对二者表达的调控方式有所不同，刺激后期Smad3表达水平的下调可能与TGF-β3负反馈调节自身的信号有关。     

骨性Ⅲ类错He畸形对语音功能的影响

为了探讨骨性Ⅲ类错Ｈｅ畸形对语音功能的是否有影响，我们以２０名骨性Ⅲ类错Ｈｅ畸形的成年患者为研究对象，由语音专家对其语音进行判听，同是应用计算机语音工作站（ｃｏｍｐｕｔｅｒｉｚｅｄｓｐｅｅｃｈｌａｂ）进行了语音声学分析，结果表明：（１）多数此类错Ｈｅ患者存在的语音功能异常，在ｚｈ，ｃｈ，ｓｈ，ｚ诸输音上最常见出现发音错误，错误类型为发音失真（ｄｉｓｔｏｒｔｉｏｎ）和发音替代（ｓｕｂｓｔｉｔｕｔｉｏ     

Effects of cyclosporin A on dental alveolar bone: a histomorphometric study in rats

BACKGROUND: We have previously reported cyclosporin A (CA)-induced osteopenia around the dental alveoli of the mandibular incisors of rats. The drug-induced tooth displacement and the regional anatomical complexity around the mandibular incisors might complicate the local effects of CA. Therefore, the purpose of this study was to evaluate the dental alveolar bone histomorphology around maxillary secondary molars in CA-treated rats and to further elucidate the effects of CA on the dental alveolus. METHODS: Twenty Sprague-Dawley rats were assigned to a CA and a control group. Animals in the CA group received CA (15 mg/kg) daily and the control rats received only mineral oil. At the end of weeks 2 and 4, five animals in each group were sacrificed. Dental alveoli around the maxillary second molar region were frontally sectioned and stained with toluidine blue by undecalcified histological processing. Ten serial tissue sections, 80 microm apart, were selected for histometric evaluation. Bone volume, bone-specific surface, and osteoid formation were measured at buccal, apical, and palatal locations in dental alveolus. RESULTS: Overall bone mass in dental alveolus decreased more in the CA group than in the control group at both observation intervals. All histometric measurements, except the bone-specific surface, were significantly affected by the alveolar location (palatal, apical, and buccal) and CA therapy (P= 0.004 and <0.001, 0.001 and <0.001, 0.004 and <0.001 for drug therapy and location of the dental alveolus in bone volume, marrow volume, and the ratio of bone surface to volume, respectively). Decreased bone volume, but increased marrow volume, were noted in the CA group compared to the control group. Although the alveolar bone surface area did not differ between the CA group and the control group, greater alveolar surface-to-volume ratio was noted in the CA group. For osteoid, more decreased volume, seam width, and fractional formation surface were observed in the CA group compared to the control group (P <0.001, <0.001, and = 0.046 in osteoid volume, seam width volume, and formation surface, respectively). CONCLUSIONS: Because the bone mass and the osteoid formation in the dental alveolus around the maxillary molar region showed a decrease after CA exposure, we conclude that this drug has inhibitory effects on the dental alveoli.     

铸造冠桥基牙聚合度的计算机辅助调查

本次调查随机收集到89颗完好无损的活动代型,对摩牙和双尖牙代型分别进行颊舌向和近远中向的聚合度X线投影分析,对前牙代型因舌窝等原因,只作近远中向聚合度X线投影分析。将X片用contex FS3200型扫描机取大信息量进行扫描,输入 COMP AQ计算机,形成PCX文件。然后,将PCX文件不经失量化直接格式转换成 DWG文件,进入 AUTO.CAD,再用绘图软件ACADR12进行测量。测量结果铸造冠桥基牙的(牙合)方聚合度为12.65±6.76,与理想的(牙合)方聚合度 2～5°存在非常性差异(P<0.001),并进行临床随访 1～3.5年,冠桥无一松动或脱落。     

Comparison of fluoride concentrations in unstimulated whole saliva following the use of a fluoride dentifrice and a fluoride rinse

Recent evidence has suggested that the cariostatic effects of topical fluoride (F) are related to the presence of low concentrations of ionic F in the oral environment. The purpose of this study was to compare the retention of F in the oral environment over 24-hour periods after the use of a F dentifrice or a F rinse. Groups of ten consenting adult subjects (age 18-52 years) brushed and/or rinsed (B/R) in a standardized manner twice per day in the morning (AM) and before bed (PM) with either a placebo dentifrice (8 ppm F), NaF dentifrice (1100 ppm F), or NaF rinse (225 ppm F). Experiments were performed with placebo dentifrice only (PD); F dentifrice only (FD); F dentifrice followed by F rinse (FD/FR); placebo dentifrice followed by F rinse (PD/FR); and F rinse followed by placebo dentifrice (FR/PD). Unstimulated whole saliva samples were collected at baseline and then at 0, 15, 30, and 45 min, 1, 2, and 8 hr after B/R in the AM, after B/R in the PM and upon rising the following morning. Salivary flow rate and F were determined for each sampling interval. The results of this study suggest that: (1) F rinse may be a more effective way of delivering topical F than F dentifrice; (2) based on F retention, the combination of FD/FR was not more effective than FR only (PD/FR); (3) older individuals with gingival recession retained higher F levels; and (4) bedtime F application resulted in longer F retention than did daytime application, which may have important implications for enamel remineralization.