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31.
恶性肿瘤导致死亡的主要原因之一是肿瘤细胞向周围组织的浸润及远处转移。因此,对肿瘤侵袭能力和转移机制的研究将为预防肿瘤侵袭转移提供新的思路。肿瘤的浸润、转移是一个相当复杂的多步骤过程,主要包括细胞黏附、基质分解及远处侵袭三个环节。Rho全称Ras相似物  相似文献   
32.
牵引成骨术(DO)中新骨的形成具有胚胎骨的发生和正常骨折愈合的某些特征,骨形成蛋白家族(BMPs)在其中扮演了重要角色。本文就BMPs与DO的生物学联系、作用调节机制、外源性BMPs的应用等方面作一综述。  相似文献   
33.
目的 :了解恶性高热患者与普通麻醉手术患者体温、血清钙及肌酸激酶 (CK)等变化。方法 :对 6例恶性高热患者及 12例对照病人进行体温、血清钙及肌酸激酶等测定。结果 :恶性高热的发生与病变类型及年龄无关 ;血清钙及肌酸激酶显著升高是恶性高热的重要指标。结论 :恶性高热是一个独立性疾病 ,麻醉用药是诱因 ,血清Ca2 + 、CK显著升高是其重要指标 ;其发生与年龄、性别、病变类型及季节 (室内 )温度无明显关系。镇静止惊是治疗MH的关键步骤 ,治疗中严禁补钙  相似文献   
34.
OBJECTIVE: The aim of this study was to investigate the correlations among the expression of osteoprotegerin (OPG) in synovial tissue and the degree of synovitis, the degeneration of articular cartilage, and the adhesions in patients with internal derangement and osteoarthritis of the temporomandibular joint (TMJ).Study design The expression of OPG, which was detected immunohistochemically, and the degree of arthroscopy of 31 patients with internal derangement and osteoarthritis of the TMJ were assessed and the correlations between them were analyzed statistically. RESULTS: OPG was expressed in the cytoplasm of the endothelial cells, synovial lining cells, and fibroblast cells. TMJs with osteoarthritis had a higher degree of articular cartilage degeneration than did TMJs with internal derangement. There was a correlation between the expression of OPG in the endothelial cells and the degree of the articular cartilage degeneration (P <.01). CONCLUSION: The expression of OPG might be associated with the development of degenerative changes of articular cartilage.  相似文献   
35.
五倍子对釉质抗酸蚀作用的实验研究   总被引:2,自引:0,他引:2  
目的:观察中药五倍子对釉质抗酸蚀作用的效果。方法:采用500g/L五倍子水浸剂为实验组,去离子水为阴性对照,20g/L氟化钠为阳性对照,对60个正常离体牙釉质表面进行处理,制备人工龋模型,用硬组织切片机制备100μm原切片,通过显微放射照射系统观察测量五倍子对釉质的抗酸蚀作用效果。结果:500g/L五倍子水浸剂组较去离子水对照组脱矿少(P〈0.05),与20g/L氟化钠对照组相比无显著差异(P〉0.05)。结论:500g/L五倍子水浸剂可明显增强釉质抗酸蚀能力,其效果与20g/L氟化钠相当。  相似文献   
36.
Multiple odontogenic keratocysts (OKCs) are principle features of nevoid basal cell carcinoma syndrome (NBCCS; Gorlin-Goltz syndrome). NBCCS is a genetic disorder transmitted by an autosomal dominant gene with variable expressivity, which is important to recognize when a patient has multiple OKCs. The cysts of the jaws are among the most common findings. Another feature is a certain appearance of the face, such as: large calvaria, high-arched eyebrows, broad nasal root, and mild hypertelorism. Before-therapy diagnosis is, therefore, as important as after-therapy diagnosis. Genetic counseling and examination may also be indicated. The purpose of this paper was to present a family case report of nevoid basal cell carcinoma syndrome with multiple odontogenic keratocysts. The features identified by these combined clinical, imaging, and histologic findings are described, along with a brief mention of the family history and a review of the literature.  相似文献   
37.
牙色度分析在原位乳牙脱矿与再矿化检测中的应用   总被引:1,自引:0,他引:1  
Zhao SM  Wang J 《上海口腔医学》2011,20(5):527-530
目的:验证数码照相牙色度分析法进行体内乳牙脱矿与再矿化研究的可行性。方法:选取58例平均年龄为4岁的儿童,以左上中切牙为实验牙,先染色、数码拍照,然后对实验牙面进行酸蚀、染色、数码拍照,最后在口腔环境内自然再矿化24h和1周后再染色、拍照,运用图像分析软件进行牙色度R、G、B值分析,比较酸蚀脱矿及再矿化前后牙色度的变化。用SPSS 19.0软件包对数据进行方差分析。结果:酸蚀脱矿后及再矿化24h后的色值(R、G、B)与基值有显著差异(P<0.05);在1周时间点上,只有B值与基值有显著差异(P<0.05);再矿化24h及1周后,牙色度值与酸蚀后相比有显著差异。结论:数码牙色度分析法可识别乳牙脱矿及再矿化前后牙色度的变化,可用于原位乳牙脱矿与再矿化研究。  相似文献   
38.
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.  相似文献   
39.
用傅立叶变换红外光谱仪研究复合树脂的双键转化度   总被引:1,自引:0,他引:1  
为了研究牙科复合树脂的聚合,采用傅立叶变换红外(Fouriertransforminfrared,FTIR)光谱仪测定8种牙科复合树脂的双键转化度并比较了压片制样法和薄膜制样法对转化度的影响。结果发现,树脂的双键转化度在45%~74%之间;可见光固化树脂的转化度高于化学固化树脂者。在光固化树脂中,混合填料树脂的转化度高于超微填料树脂者,粘接辅助剂的转化度最高。对光固化树脂而言,压片制样法所测得的转化度值高于用薄膜制样法;而在化学固化树脂,用二种制样方法所测得的转化度值相同。本研究结果可供临床应用复合树脂参考。  相似文献   
40.

Objective

Antigen I/II of mutans streptococcus (MS) is a surface protein, which binds to salivary receptors. The objective of this study was to study the effect of a peptide corresponding to residues 1025-1044 of antigen I/II and a dentifrice containing peptide on the adherence of MS.

Methods

The peptide was synthesized and included into dentifrice. Anti-adherence experiments of the peptide and a dentifrice containing it were processed in vitro and in vivo.

Results

The results showed that the adherence of MS to hydroxyapatite was inhibited by synthetic antigen I/II peptide and also by a dentifrice containing the peptide in vitro. The numbers of MS in plaque from subjects treated with dentifrices containing the peptide for 1 month was significantly reduced compared to baseline (log 3.11 ± 0.80 vs log 4.09 ± 0.90, P < 0.01), whereas the control group showed no reduction.

Conclusion

The adherence of MS to hydroxyapatite was inhibited by both a synthetic peptide and a dentifrice containing the peptide. The peptide dentifrice produced a significant reduction of MS in dental plaque in vivo.  相似文献   
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