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21.
The study of teeth,dentition and occlusion is helpful to guide oral medical clinic and the study of anthropology.Our department of Osaka Dental University and had many items of research work about teeth,dentition and occlusion between Chinese and Japanese students.This article reports the study of Carabelli cusp.The results revealed:(1)the rate of Carabelli cusp is higher in Japanese than in Chinese and is higher in male than in female.(2)the rate of Carabelli cusp of the first maxillary molar of both side is very high.(3)The rate of Carabelli cusp is related to the height and the type of cusp numbers.These all illustrated the occurence of Carabeiil cusp were influenced by race, individual and the development of teeth.  相似文献   
22.
Thirteen normal subjects were selected for this investigation. At the vertical dimension of rest position and habitual clench, their myoelectric activities of the masseter, anterior and posterior temporal, and digastric muscles on the left and right sides were simultaneously sampled and processed by computer, and the mean power frequency (MPF) and the mean amplitude (MA) of the myoelectric signal were calculated. At rest position, the temporal muscles were major muscles and the MPF differences of various masticatory muscles were not significant. At habitual clench, with the increase in MA, the MPF of various muscles increased. The results show that MPF may have application in describing a central tendency of myoelectrical signal frequency distribution and in evaluating recruitment of motor units. MPF and MA are the quantitative indices reflecting masticatory muscle function.  相似文献   
23.
目的 探讨术前正畸对行正畸-正颌联合治疗的骨性Ⅲ类错颌患者颞下颌关节(TMJ)的影响。方法 选取24例行正畸-正颌联合治疗的骨性Ⅲ类错颌患者,分别在术前正畸完成前后检查并记录关节症状,并行锥形束CT(CBCT)扫描,在三维方向测量髁突各径值(d)、髁突高度(h)、不同角度下关节间隙(L)、双侧髁突间距(R)及各髁突角度值,比较和分析不同时期TMJ症状及骨性结构的变化情况。结果 术前正畸前后关节症状无明显改变;颞下颌关节骨性结构在三维方向上的各测量指标均无显著变化(P>0.05)。结论 在正畸-正颌联合治疗过程中,术前正畸不会对患者TMJ产生明显影响。  相似文献   
24.
Problem-based learning (PBL) is a widely accepted educational method centered on the discussion and learning that emerge from a clinically based problem; however, little has been reported on the details of PBL case-writing in the dental education literature. This article outlines some principles of writing a PBL case as it is practiced at a Chinese dental school and presents, as an example, an actual case based on a clinical problem (ameloblastoma of the jaw) intended to provide a learning focus for predoctoral dental students. A good PBL case should allow for progressive, interdependent actions to be taken in the evaluation and overall management of the patient in context and should trigger inquiry and discussion among students in both the basic sciences (anatomy, physiology, biochemistry, pharmacology, pathophysiology, etc.) and related clinical sciences. The epidemiological, sociological, and ethical considerations related to each problem should also be emphasized as an essential component of effective health care provision.  相似文献   
25.
本文对99例复发性口疮患者,分别在初诊治疗前(发作期)和治疗后3月未发作时进行唾液SIgA、IgG、IgM、C3、C4及溶菌酶含量和活性检测,并以45名健康学生唾液相应成份作为正常对照。实验结果表明:复发性口疮患者治疗前唾液SIgA、IgG、IgM、C3、C4及溶菌酶含量和活性,均远远低于正常人唾液相应成份(P<0.01);复发性口疮患者治疗后,其唾液SIgA、IgG、IgM、C3、C4及溶菌酶含量和活性,均较治疗前有显著提高(P<0.01),其中IgG、C4及溶菌酶含量和活性恢复较明显,与正常人唾液相应成份相似(P>0.05)。  相似文献   
26.
Ti—75铸造后机械性能测试的研究   总被引:7,自引:1,他引:7  
目的:研究及比较Ti-75金属在牙科铸造后的机械性能。方法:利用Instron拉伸试验机,对Ti-75金属牙科铸造后部分力学性能进行了测试研究,并与Ti-6Al-4V及临床常用钴铬合金进行了比较。结果:Ti-75铸造后抗拉强度为856.7MPa,屈服强度为540MPa延伸率为7.3%。Ti-6Al-4V铸造后抗拉强度为956.7MPa,屈服强度为590MPa,延伸率为5.2%。Co-Cr合金铸造后抗拉强度为651.2MPa,屈服强度为478.8MPa,延伸率为6.1%。结论:Ti-75金属铸造后抗拉强度,屈服强度及延伸率等性能指标均优于钴铬合金,延伸率也高于Ti-6Al-4V合金。  相似文献   
27.
With a global prevalence of 7.7 million, ischemic stroke (IS) is one of the leading causes of death and disability worldwide. In China, IS alone contributed to 69.6%? of stroke events and accounted for 37.1%? of the mortality/disability rate[1]. IS is a complex disease that is known to be associated?with?various?genetic?variants?and?clinical and lifestyle risk factors[2]. Genome -wide association studies (GWAS) provided evidence for the?occurrence?of?more?than?160?IS-associated?single nucleotide?polymorphisms?(SNPs).?In?terms?of?clinical risk factors, patients with a history of chronic diseases like hypertension, dyslipidemia, and diabetes mellitus, display a higher risk of developing IS. Among the various lifestyle components, leading a sedentary lifestyle, smoking, and having an unhealthy diet are known to be associated with the risk of IS. Thus, integration of various genetic, clinical, and lifestyle variables might prove to be highly beneficial in the prediction and prevention of IS?at?the?individual?level[3].  相似文献   
28.
目的探讨术中x-线定位在经神经内镜下甲介型蝶窦垂体瘤手术的应用。方法回顾性分析6例甲介型蝶窦垂体瘤病人的临床资料,均采用神经内镜下垂体瘤切除结合术中X-线定位方法。结果术中X-线定位准确4例;2例发生纵向偏差,均纠正。肿瘤全切除5例,次全切除1例。术后激素水平正常,视力视野改善。出现暂时性尿崩1例,治疗后痊愈。无脑脊液鼻漏、垂体功能低下、蝶窦炎发生,无死亡病例。6例病人随访3年,均无复发。结论神经内镜技术结合术中X-线定位是一种治疗甲介型蝶窦垂体瘤的安全、有效方法。  相似文献   
29.
30.
Epidemiological studies demonstrate that pain frequently occurs comorbid with depression. Gentiopicroside (Gent) is a secoiridoid compound isolated from Gentiana lutea that exhibits analgesic properties and inhibits the expression of GluN2B-containing N-methyl-d-aspartate (NMDA) receptors in the anterior cingulate cortex of mice. However, the effects of Gent on the reserpine-induced pain/depression dyad and its underlying mechanisms are unclear. Reserpine administration (1 mg/kg subcutaneous daily for 3 days) caused a significant decrease in the nociceptive threshold as evidenced by the reduced paw withdrawal latency in response to a radiant heat source and mechanical allodynia. Behavioral detection indicated a significant increase in immobility time during a forced swim test, as well as decreased time in the central area and total travel distance in an open field test. Furthermore, reserpinized animals exhibited increased oxidative stress. Systemic Gent administration dose-dependently ameliorated the behavioral deficits associated with reserpine-induced pain/depression dyad. At the same time, the decrease in biogenic amine levels (norepinephrine, dopamine, and serotonin) was integrated with the increase in caspase-3 levels and GluN2B-containing NMDA receptors in the amygdala of the reserpine-injected mice. Gent significantly reversed the changes in the levels of biogenic amines, caspase-3, and GluN2B-containing NMDA receptors in amygdala. However, Gent did not affect the expression of GluN2A-containing NMDA receptors. The inhibitory effects of Gent on oxidative stress were occluded by simultaneous treatment of GluN2B receptors antagonist Ro25-6981. Our study provides strong evidence that Gent inhibits reserpine-induced pain/depression dyad by downregulating GluN2B receptors in the amygdala.  相似文献   
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