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101.
Nd:YAG激光对牙本质钙/磷比值的影响 总被引:1,自引:0,他引:1
朱庆萍 《临床口腔医学杂志》1998,14(3):131-132
为探讨Nd:YAG激光对牙本质矿物含量的影响,应用扫描电镜和能谱仪定点测量50个上前牙标本的根管壁(激光照射工和正常对比区)的钙、磷含量,结果表明,照射区牙本质钙/磷(Ca/P)比值高于对比区,当激光能量达15W以上时变化更为显著,提示Nd:YAG激光能提高牙本质的钙化程度。 相似文献
102.
M. A. El-Kalay M. H. Abdel-Kader† R. Y. Hamzah† S. A. Al-Shirbini† 《Artificial organs》1990,14(3):200-207
Using a plasma separator, it is possible to wash large volumes of whole blood free of plasma proteins in short periods. The novelty, however, is that the same apparatus can be used to reversibly hemolyze and reseal the red blood cells (RBCs) using hypotonic and hypertonic dialysates, respectively. This technique was assessed using the fluorescent exogenous agent uranin (fluorescein sodium). Results indicate that the encapsulation of the RBCs can be completed in under 2 h. The encapsulation efficiency of the RBCs was approximately 80% with a RBC recovery rate of 75%. 相似文献
103.
Teaching of medical ethics 总被引:1,自引:0,他引:1
Teaching medical ethics in Manchester within the introductory course of obstetrics and gynaecology is a joint activity with the Centre for Social Ethics and Policy. This interdisciplinary teaching has evolved through lecture sessions with small-group discussions dealing with topics of interest in human reproduction. The small-group discussion have been replaced by an open debate conducted by the students. Their own involvement and participation and an exposure to the disciplines of the humanities has broadened their approach to different ways of problem-solving of these real issues. 相似文献
104.
William V. Giannobile Rafaél A Hernandez Richard D. Finkelman Susan Ryarr Christopher P. Kiritsy Mark D'Andrea Samuel E. Lynch 《Journal of periodontal research》1996,31(5):301-312
Platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I) in combination have previously been shown to enhance periodontal regeneration. The objective of this study was to further characterize the biological effects of this combination of growth factors in non-human primates and compare the effects to those of each growth factor individually. Ligature-induced periodontitis was initiated in 10 cynomolgus monkeys. After periodontal lesions were established, surgery was performed, and either a methylcellulose gel vehicle or vehicle containing 10 μg each of either PDGF-BB, IGF-I or both PDGF-BB and IGF-I was applied to exposed root surfaces. Biopsies were taken 4 and 12 wk after treatment and the extent of periodontal regeneration was assessed by histomorphometry. At both 4 and 12 wk vehicle-treated lesions generally revealed minimal osseous defect fill (ODF) (8.5±2.1% and 14.5±5.7%, respectively) and new attachment (NA) (34.1±5.2% and 26.6±10.5%, respectively). IGF-I treatment did not significantly alter healing compared to vehicle in any parameter at both 4 and 12 wk. PDGFBB-treated sites exhibited significant (p<0.05) regeneration of NA (69.6±12.0%) at 12 wk; trends for PDGF-BB treatment effect were also observed in other parameters at 4 and 12 wk. although these increases were not statistically significant. Treatment with PDGF-BB/IGF-I resulted in 21.6±5.1 % and 42.5±8.3% ODF at 4 and 12 wk, respectively, and 64.1±7.7% and 74.6±7.4% NA at 4 and 12 wk, respectively (all significantly greater than vehicle, p<0.05). The results from this study demonstrated that: 1) IGF-1 alone at the dose tested did not significantly alter periodontal wound healing; 2) PDGF-BB alone significantly stimulated NA, with trends of effect on other parameters; and 3) the PDGF-BB/IGF-I combination resulted in significant increases in NA and ODF above vehicle at both 4 and 12 wk. 相似文献
105.
106.
测定72例健康老年人(60-84岁)和65例健康青中年人(20-50岁)血清和尿β2微球蛋白(β2m),发现前血清β2m浓度比后明显增高(p<0.001);老年组≥70岁尿液β2m浓度也明显增高(p<0.05)。结果表明肾小球滤过率下降随年龄增长而降低,以后再出现肾小管功能减退。本试验较血清尿素氮、肌酐和内生肌酐清除率测定更为敏感。 相似文献
107.
María Luz Montesinos Manuel Castellano-Muoz Pablo García-Junco-Clemente Rafael Fernndez-Chacn 《Brain Research Reviews》2005,49(2):416-428
In neurons, a network of endocytic proteins accomplishes highly regulated processes such as synaptic vesicle cycling and the timely internalization of intracellular signaling molecules. In this review, we discuss recent advances on molecular networks created through interactions between proteins bearing the Eps15 homology (EH) domain and partner proteins containing the Asn–Pro–Phe (NPF) motif, which participate in important aspects of neuronal function as the synaptic vesicle cycle, the internalization of nerve growth factor (NGF), the determination of neuronal cell fate, the development of synapses and the trafficking of postsynaptic receptors. We discuss novel functional findings on the role of intersectin and synaptojanin and then we focus on the features of an emerging family of EH domain proteins termed EHDs (EH domain proteins), which are important for endocytic recycling of membrane proteins. 相似文献
108.
目的:探讨湿润暴露疗法治疗会阴部Ⅱ度烧伤患者的临床效果。方法:将我院2005年6月~2006年6月间规范应用湿性医疗技术治疗的32例会阴部烧伤患者进行临床分析、总结。结果:全部病例均治愈,且烧伤创面愈合快,不形成瘢痕。结论:应用MEBT/MEBO治疗会阴部烧伤,方法简单,护理方便,临床疗效满意,值得推广。 相似文献
109.
后天性外耳道狭窄的手术治疗 总被引:1,自引:0,他引:1
目的探讨后天性外耳道狭窄的手术治疗方法及效果。方法对26例(27耳)外耳道狭窄行外耳道成形术或厢乳突根治鼓室成型术,取大腿内侧自体游离中厚皮片植皮,碘仿纱条压迫并扩张耳道。结果26例病人27耳随访6个月至8年,24耳外耳道宽敞,无再狭窄;3耳出现轻度狭窄,发生率11.1%(3/27),效果满意。结论对后天性外耳道狭窄的治疗可根据狭窄的原因、部位及程度等不同情况采用外耳道成形、游离中厚皮片移植或同时进行乳突根治鼓室成型术等手术治疗,术后局部换药,即能取得较好效果。 相似文献
110.