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1.
聚酰胺—胺树枝状聚合物(PAMAM)作为一种新型超支化大分子聚合物,因其出色的化学和生物学特性,一直被众学者称之为“人工蛋白”。 PAMAM的特点是存在内部空腔,并含有大量的反应性末端基团,这些结构使得PAMAM可以被用作仿生大分子,模拟天然有机基质在牙体组织表面进行仿生矿化,即PAMAM作为有机模板调控矿物质成核以及晶体的生长,以此来建造比传统的异体材料更加理想的牙体修复材料。本文就 PAMAM 诱导牙体硬组织仿生矿化的研究进展作一综述。  相似文献   
2.
目的:运用软硬腭前移的手术方法扩大鼻咽下口,改善因鼻咽部狭小致阻塞性睡眠呼吸暂停综合征患者的呼吸暂停症状。方法:手术切除硬腭后份使其缩短、悬雍垂软腭成形并将软腭拉向前,扩大鼻咽下口。结果:患者术后自觉症状及客观评价疗效满意。结论:软硬腭前移鼻咽下口扩大显著改善鼻咽下口狭小导致的阻塞性睡眠呼吸暂停患者的症状。  相似文献   
3.
目的 探讨贫困地区超声乳化联合小切口硬核白内障摘除联合PMMA人工晶状体植入手术的疗效。方法 对336例(336只眼)Ⅳ级以上核白内障行超声乳化联合小切口晶状体摘除联合PMMA人工晶状体植入术。结果 术后1天、3天视力在0.5以上分别为240只眼(71.4%)、265只眼(78.8%)。术中主要并发症为后囊破裂。术后主要并发症为角膜水肿、眼压升高。结论 超声乳化联合小切口晶状体摘除治疗Ⅳ级以上核白内障切口小,术后反应轻,散光小,并且视力恢复快,费用低。手术技巧的提高可避免或减少术中术后并发症。  相似文献   
4.
目的 研究青少年拔牙矫治时颅面部硬组织的影响。方法 选择50例为青少年恒牙He,安氏Ⅰ类患者,25例需拔除四个第一双尖牙治疗,25例无需拔牙治疗,用标准方丝弓技术矫治,共收集到完整病例43例,拔牙20例,非拔牙23例,利用X线头影测量技术,比较拔牙与非拔牙组治疗前后的变化。结果 拔牙矫治与非拔牙矫治组都存在一定的颅面部骨骼的生长,但两者矫治前后改变无明显差别。拔牙矫治明显改变了前牙位置。结论 青少年拔牙矫治期间对颅面部骨骼的改变无影响。  相似文献   
5.
A new two-step deprotection/cleavage procedure for t-butoxycarbonyl (Boc) based solid phase peptide synthesis is reported. First the protective groups are removed from 4-(oxymethyl)-phenylacetamidomethyl (PAM) resin attached peptide with the weak hard acid, trimethylsilyl bromide-thioanisole/trifluoroacetic acid (TFA). In the second step, the peptide is cleaved from the resin with a stronger hard acid such as trimethylsilvl trifluoromethanesulfonate in TFA or with HF. The method is also shown to deformylate Nin-formyltryptophan moiety efficiently. The usefulness of this procedure for practical solid phase peptide synthesis is demonstrated by comparison with other deprotection methods in the synthesis of urotensin II and human endothelin.  相似文献   
6.
Sialolipoma is a new variant of salivary gland lipoma, which was first proposed by Nagao et al. (Histopathology 2001; 38: 30) in 2001. We report this rare case of sialolipoma in the hard palate. A 60-year-old Japanese woman was referred to our department complaining of a painless swelling on the right side of the hard palate. Intra-oral examination revealed a soft, elastic, dome-shaped mass with 1 cm in diameter located in the posterior part of the hard palate. Magnetic resonance imaging examination revealed high intensity on T(1)-weighted image and isointensity on T(2)-weighted image. Incisional biopsy revealed that the tumor was encapsulated by fibrous tissue, consisted of adipose tissue, and also contained normal salivary gland tissue peripherally. First diagnosed as an ordinary lipoma of the hard palate, the tumor was excised. According to the recent criteria of histologic findings of sialolipoma, we rediagnosed the tumor as sialolipoma of the hard palate.  相似文献   
7.
Wide-field specular microscopy, slit-lamp examination, and pachometry were performed on 22 successful hard contact lens wearers and 22 controls matched for age, race, sex, and refractive error. A minimum of 600 cells per control and 1200 per contact lens wearer were manually digitized from the specular photomicrographs. Frequency distributions of cell areas were compared between the two groups using the parameters of mean, median, standard deviation, coefficient of variation, skewness and kurtosis. Slit-lamp examination was normal and there was no significant difference in corneal thickness between the patient group and the control group. Comparison of mean, median, and standard deviation also revealed no significant difference, but skewness (P less than .001), kurtosis (P less than .001) and coefficient of variation (P less than .004) were greater in the hard contact lens wear group. Hard contact lens wearing time correlated with increasing pleomorphism (P less than .05). Specular microscopy also revealed morphologic changes including deep stromal striae, intra- and extracellular "blackout" areas, and clustering of extremely small and large cells. The possible relationship between endothelial hypoxia and structural stromal changes are discussed.  相似文献   
8.
Gravieras are ‘gruyere’ type hard cheeses with a variety of different products and the second highest consumption in Greece. In this study, we present a dietary intake assessment and a nutritional characterization of pre-packed graviera products sold in the Greek market using Nutri-Score Front of Pack Label (FoPL). The nutrient contents of 92 pre-packed graviera products were combined with daily individual consumption data extracted from the Hellenic National Nutrition Health Survey (n = 93), attempting to evaluate the contribution of graviera’s consumption to the Greek diet. The analysis of nutrients’ intake as a Reference Intake (RI) percentage ranked saturated fat first on the nutrients’ intake list, with RI percentage ranging from 36.1 to 109.2% for the 95th percentile of consumption. The respective % RI for energy, total fat, carbohydrates, sugars, proteins and salt ranged from 12.7–20.7%, 21.6–50.4%, 0–3.1%, 0–6.1%, 37–57.1% and 6.3–42%. Nutri-Score classified 1% of the products to C—light orange class, 62% to D—orange and 37% to E—dark orange, while no products were classified to A—dark green or B—green classes. The comparison between the Nutri-Score classification and the nutrients’ intake assessment, also separately conducted within the classes, showed a higher salt intake after the consumption of products classified as D—orange and E—dark orange.  相似文献   
9.
目的:研究中国蒙古族正常He成年人颅颌面软硬组织三维X线头影测量数据在临床中的作用。方法:选择符合正常He标准的蒙古族成年人98名(男女各半),对颅颌面软、硬组织进行三维X线头影测量分析。结果:①颅颌面软组织的测量:蒙古族与汉族相比,面型较平直,面部较宽;与美国白人相比,蒙古族的上唇位于下唇前方,美国白人的上唇位于下唇后方。相对国人汉族而言,蒙古族上、下唇位置均靠后;蒙古族本民族的面型女性比男性宽而短。②颅颌面硬组织的测量:与蒙古族本民族相比,线距有性别差异,角度无性别差异,同一受检者左右相同项目测量,结果不完全一样。与不同民族相比,线距在矢状、横向、垂直三维方向与广东人、西安人有显著差异。结论:①蒙古族正常He成年人颅颌面左右侧的软硬组织存在着属于正常范围的不对称现象;②与不同民族和种族相比,蒙古族颅颌面软、硬组织形态具有明显的性别差异和种族特点;③本研究获取了蒙古族正常He成年人颅颌面软、硬组织的三维X线测量数据,建立了蒙古族自己的数据库;④蒙古族成年患者在正颌外科和牙齿正畸的诊断、设计和治疗中,应参考本民族颅颌面软硬组织的正常值和属于正常范围的面部左右不对称现象。  相似文献   
10.
Summary Plasma levels of temazepam were determined in healthy subjects after single oral administration of soft and hard gelatin capsules, and after 7 consecutive night-time doses in soft capsules. Absorption from soft gelatin capsules was significantly faster and produced earlier and higher peak plasma levels. The two pharmaceutical forms did not show any significant difference in relative availability. The apparent half-life of temazepam after night-time administration was significantly shorter than after morning administration, but no change in half-life was observed between the first and seventh night-time doses.  相似文献   
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