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11.
The purpose of the present study was to determine the reliability of several selected signs of trauma from occlusion and their relations with severity of periodontitis. 32 moderate to advanced chronic periodontitis patients participated in the study. All teeth present were evaluated for various abnormal occlusal contacts, signs of trauma from occlusion, and the severity of periodontitis. Standardized periapical radiographs were also taken for each tooth. The results demonstrated that: (1) no significant difference occurred in probing pocket depth (PD), clinical attachment loss (AL), or percentage of alveolar bone height (BH) between teeth with and without various abnormal occlusal contacts, i.e., premature contacts in centric relation occlusion, non-working contacts in lateral excursions, premature contacts of anterior teeth or posterior protrusive tooth contacts; (2) teeth with either significant mobility, functional mobility, or radiographically widened periodontal ligament space (PDLS) had deeper PD, more AL and lower BH than teeth without these signs, while teeth with pronounced wear or radiographically thickened lamina dura had less AL than teeth without these findings; (3) 2 combined indices, i.e., the trauma from occlusion index (TOI) and the adaptability index (AI), were proposed for the identification of occlusal trauma and the response of periodontium to excessive biting forces in heavy function, respectively; TOI-positive teeth exhibit deeper PD, more AL and less osseous support than TOI-negative teeth; however, AI-positive teeth had less AL and more osseous support than AI-negative teeth; (4) with identical attachment level, TOI-positive teeth had less osseous support than TOI-negative teeth while the magnitude of difference became greater with an increase of attachment loss.  相似文献   
12.
目的 观察急性脑梗死 (ACI)后血浆一氧化氮 (NO)、一氧化氮合成酶 (NOS)、内皮素 (ET)含量的动态变化 ,以及尼莫地平治疗后对其影响。方法 ACI患者 110例 ,随机分成尼莫地平组 (5 0例 ) (在常规治疗基础上用尼莫地平 )和常规治疗组 (6 0例 )。在发病后不同时点动态观察血浆NO、NOS、ET含量 ,并设 5 0例脑动脉硬化患者为对照组。结果 脑梗死后血浆ET含量显著升高 ,直至恢复期 ;NO、NOS先增高后下降 ;尼莫地平组和常规组比较ET有显著差异 (P <0 .0 1) ,NO、NOS差别不显著 (P >0 .0 5 )。结论 NO、NOS、ET参与并影响了ACI后复杂的病理生理过程 ;尼莫地平部分通过对ET含量的影响发挥其对脑梗死的治疗作用  相似文献   
13.
Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese. WANG Tao, male, born in 1961, Associate Professor This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial No. WJ 01529).  相似文献   
14.
The paper describes the prenatal ultrasonographic diagnosis of conjoined syncephalus-craniothoraco-omphalopagus twins at 13 weeks' gestation. The mother, after genetic counseling, decided to interrupt the pregnancy. The fetal karyotype, the maternal serum and amniotic fluid alpha-fetoprotein levels were normal. The diagnosis was confirmed by pathologic examination of the fetus after termination of pregnancy.  相似文献   
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取32只2~3个月的BALB/C小白鼠,随机分为4组,每组8只,第1组为对照组,其余3个组为实验组,实验组小白鼠左腿皮下注射苯0.3ml(15ml/kg体重).注射后分别于24h,48h,72h脱颈处死。观察中毒前、后末梢血象、骨髓细胞、骨髓细胞构成的变化。结果表明,苯中毒时骨髓变化先于末梢血象的变化,骨髓的病变为造血细胞变性、坏死,大量毛细血管扩张、充血,骨髓细胞构成降低,而且骨髓细胞构成中细胞成分降低早于外周血粒细胞减少。  相似文献   
17.
笔者从事临床医疗工作20余年,自拟解毒消肿散治疗因阳热毒邪蕴蒸肌肤所致的多种外科疾患,屡获捷效,现报道如下。方药组成与使用方法蒲公英30g,紫花地丁30g,玄明粉50g,冰片6g,共研细末调和均匀,贮瓶密封备用。使用时,视肿疡面积大小,取适量药粉,用食醋调成糊状,摊敷在病变部位,厚约0.5~0.8cm,用塑料薄膜覆盖,外用胶布固定。药物干燥时,可再用食醋浸湿。每日换药2~3次。本方具有清热解毒、散瘀消肿、消炎止痛的作用。主治痈、疽、疔、疖、乳痈、痄腮、毒虫咬伤、痔瘘、肛裂、无名肿毒等证,凡红肿热痛属阳证、热证、实证者均可应用,阴证、寒证…  相似文献   
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19.
An animal model of chronic tympanic membrane perforation.   总被引:6,自引:0,他引:6  
Previous investigations into the healing and reconstruction of tympanic membrane (TM) perforations have involved animal models with acute TM perforations. A problem with the acute TM perforation model is that most acute TM perforations will heal spontaneously, both in animals and human beings. A second inadequacy of acute perforation models is that they are not analogous to the salient problem in human beings: long-standing TM perforation. The ideal animal model must have a TM perforation that is permanent, well-epithelialized, and free from infection. The perforation must also be subtotal to preserve a rim of membrane for experimental manipulations. In the chinchilla, we have identified a hardy animal with a short, wide ear canal and relatively large tympanic membranes. Thermal myringectomy, followed by medial infolding of TM microflaps, has resulted in permanent, subtotal chronic TM perforations in the chinchilla animal model. Of the 19 chinchillas (38 TMs) perforated, chronic subtotal perforations were created in 32 ears, 6 to 8 weeks after the initial procedure (84% success). Persistent infection or TM regeneration despite reperforation was recorded in 6 ears (16%) failure). This model is currently being used to assess various biomembrane scaffolds impregnated with growth-promoting substances in the regeneration of a physiologically sound TM, initially in our animal model and then in human beings. We envision the development of a biomembrane disc impregnated with biorecombinant growth factors that may provide a simple office technique for the repair of chronic, non-infected TM perforations.  相似文献   
20.
报道辐照氟银猪皮的制备、实验检测(弹性、创面粘附力和透水性测定,含银量测定)组织学检查细菌检测及抑菌试验研究,结果表明:辐照氟银猪皮除延伸度低于未辐照猪皮外,其撕裂强度、创面粘合力和透水性均与未辐照猪皮相似。组织学检查示:辐照氟银猪皮组织结构完整,表皮细胞部分空泡形成。组织细菌检测证明其无菌生长,达到无菌要求。抑菌试验证明对金黄色葡萄球菌、绿脓杆菌、大肠杆菌、变形杆菌、克雷伯氏菌均有极强的抑菌作用  相似文献   
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