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81.
目的:评价传统的玻璃离子水门汀所产生的,特别是用于无创伤充填治疗技术时抑制体外釉质脱矿的能力.方法:二十四颗由于正畸治疗拔除的完整的恒前磨牙,在釉质颈部作洞型预备.这些牙齿分别用Fuji IX,Fuji IX GP,Ketac-Molar和复合玻璃充填材料充填,将它们放在5℃~55℃的温度下循环处理300次,后放在放在脱矿溶液(含有1g/l的溶解的羟磷灰石的0.1M的乳酸,pH为4.7)中四个星期.沿牙齿的长轴经充填体作平行于颊舌平面的切片,切片的厚度大约为100 μm.用偏振光显微镜检测这些切片,用图像分析软件分析病损大小,ANOVA和变异系数用于比较结果.结果:复合玻璃和Ketac-Molar比其它两种水门汀的表面腐蚀性小(P<0.01).用玻璃离子水门汀瞬间接触充填体边缘抑制釉质脱矿的能力(20.5%~25.0%)较复合玻璃材料强(13.0%).但是,抑制带的宽度因材料和位置的不同而有变异.结论:充填材料释放的氟离子在某种程度上为邻近釉质抵抗体外脱矿提供保护.  相似文献   
82.
OBJECTIVE: To address the issue as to how best to perform statistical MUNE, we applied two different approaches and compared results in healthy subjects and ALS patients. METHODS: Twelve normal subjects (women 8, mean age 52years) and 11 ALS patients (women 4, mean age 54years) underwent two consecutive MUNE studies, which differed in terms of setting and modifying the recording window. These are referred to as the 'expansion' and 'narrowing' methods, respectively. Size-weighted average (Av) SMUP and MUNE values were obtained using the two methods, and compared in control and patient groups. RESULTS: Expansion method-derived Av SMUP sizes and MUNE values differed only slightly from those obtained using the narrowing method in healthy subjects, whereas the narrowing method resulted in significantly larger Av SMUP sizes and smaller MUNE values than the expansion method in ALS patients (Wilcoxon signed ranks test, p=0.003). The sizes of tested areas (mean+/-SD) were significantly larger for the narrowing method than the expansion method in both subject groups with much greater difference in ALS patients; 9.6+/-3.1% vs. 7.9+/-1.7% in healthy subjects and 16.1+/-5.1% vs. 11.2+/-3.0% in ALS patients (Student t-test, p<0.01). CONCLUSIONS: The present study shows, unlike that found in normal subjects, that the results of statistical MUNE in ALS patients are heavily dependent on the approach used to set and modify recording windows. SIGNIFICANCE: The expansion method using a 10%-sized window is likely to suffer from systemic errors due to the ceiling effect and the sampling of artifactually small motor units in ALS patients. The authors recommend that the narrowing method be considered as an alternative that avoids these problems.  相似文献   
83.
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   
84.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义   总被引:1,自引:1,他引:0  
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。  相似文献   
85.
椎管内肿瘤显微外科手术治疗   总被引:2,自引:0,他引:2  
本组收集自2000年2月至2005年12月我院椎管内肿瘤患者64例,通过显微手术治疗,取得满意效果,报告如下。一、资料与方法1.一般资料:在64例椎管内肿瘤中男性36例,女性28例;年龄最小12岁,最大76岁,平均38岁。2.主要症状与体征:(1)疼痛:疼痛为常见的首发症状,共有18例。常表现为根性疼痛,有时可误诊为肋间神经痛或坐骨神经痛。(2)感觉障碍:常见,共有54例。有不同程度的感觉障碍,表现为有感觉障碍平面并常伴有麻木或束带感。髓内肿瘤则常表现有不同程度的节段性感觉障碍,感觉障碍平面与脊髓肿瘤所在部位相关。(3)运动障碍:有52例入院时在肿瘤压迫…  相似文献   
86.
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   
87.
With the development of interventional therapy, it is necessary for evaluating cerebral vessels to instruct treatment and determine prognosis of patients with ischemic stroke; however, correlation of distribution of infarction focus and clinical symptoms with degrees of cerebrovasoular stricture is still unclear.OBJECTIVE: To evaluate the characteristics of cerebral arterial stricture of patients with ischemic stroke with transcranial Doppler (TCD) and color duplex flow imaging (CDFI) and compare the correlation between distribution of cerebral infarction focus and clinical types with magnetic resonance imaging (MRI).DESIGN: Contrast observation.SETTING: Department of Neurology, the First Hospital of Jilin University.PARTICIPANTS: A total of 159 patients with ischemic stroke were selected from the Department of Neurology, the First Hospital of Jilin University from January to December 2005, including 106 males and 53 females aged from 27 to 88 years. Bases on diagnostic criteria of cerebrovascular disease established by Rao et al, clinical manifestations of all patients were evaluated with CT or nuclear magnetic resonance. All patients provided the confirmed consent.METHODS: The accepted patients received TCD and CDFI examination at 1 week after onset of ischemic stroke. Among them, 112 patients received cerebrovascular imaging examination simultaneously. MRI was used to check cerebral infarction focus and cerebrovascular stricture > 50% was regarded as the accepted vessels. In addition, DWI-T2 TCD (Germany) was used to check middle cerebral artery, and degrees of middle cerebral artery were classified into mild, moderate and severe stricture based on blood velocity (140 cm/s,180 cm/s). Stroke was classified based on characteristics of infarction focus and clinical symptoms showed with MRI and correlation with degrees of cerebrovascular stricture was analyzed simultaneously.MAIN OUTCOME MEASURES: Correlation between the characteristics of ischemic stroke and clinical symptoms checked with TCD and CDFI.RESULTS: A total of 159 patients with ischemic stroke were involved in the final analysis; in addition, 112 oases received cerebrovascular imaging examination simultaneously. ① MRI results of 159 patients with cerebral artery occlusive disease (CAOD): There were 131 patients (82.3%) with cerebral infarction, 40 (25.2%)with transient ischemic attack and 4 (2.5%) with subclavian steal syndrome (SSS). ② Infarction types with MRI examination: There were 33 patients (20.8%) with solitary cerebral infarction and 98 (61.6%) with multiple-cerebral infarction. ③ Results of TCD, CDFI, MRI angiography, CT angiography and digital subtraction angiography (DSA): Among 112 patients, 181 lesion sites (61 .8%) were located in cranium and 112 lesion sites were located out of cranium; especially, lesion site was mostly observed in stem of middle cerebral artery (31.2%) and watershed of basilar artery (7.2%) in cranium and the beginning site of internal carotid artery (21 .4%) out of cranium. ④ Correlation of vascular stricture checking with TCD, MRI and clinical diagnosis: On one hand, MRI and clinical diagnosis demonstrated that 68 patients had a watershed infarction; meanwhile,TCD examination indicated that there were 3 patients with mild vascular stricture, 24 with moderate vascular stricture and 36 with severe vascular stricture. On the other hand, among 68 patients with non-watershed infarction, there were 27 patient with mild vascular stricture, 26 with moderate vascular stricture and 15 with severe vascular stricture. There were significant differences (x2 =26.854, P =0.001 ). Clinical diagnosis indicated that 40 patients had transient ischemic attack and TCD examination demonstrated that there were 8 patient with mild vascular stricture, 12 with moderate vascular stricture and 20 with severe vascular stricture. There were significant differences as compared with 68 patients with watershed infarction (x2 =21.258, P =0.001). ⑤Correlation of vascular stricture checking with CDFI, MRI and clinical diagnosis: On one hand, among patients who were determined as watershed infarction with MRI and clinical diagnosis, CDFI examination indicated that there were 32 patients with mild vascular stricture at neck, 25 with moderate vascular stricture and 6 with severe vascular stricture. On the other hand, among patients with non-watershed infarction, there were 48 patient with mild vascular stricture, 18 with moderate vascular stricture and 2 with severe vascular stricture.There were significant differences (x2 =6.018, P =0.019). Among patients with transient ischemic attack checking with clinical diagnosis, there were 23 patient with mild vascular stricture, 9 with moderate vascular stricture and 8 with severe vascular stricture. There were no significant differences as compared with patients with non-watershed infarction (x2 =0.597, P=0.440).CONCLUSION: ① TCD and CDFI are effective marks to determine cerebral arterial stricture and hemodynamical changes. ② Infarction and transient ischemic attack at watershed are generally clinical phenotypes of CAOD patients and infarction at watershed is correlated with degrees of cerebrovascular stricture.③ TCD, MRI and clinical analysis of stroke types are significant for instructing treatment and evaluate prognosis.  相似文献   
88.
目的 研究羊柄菜多糖复方制剂对γ射线照射小鼠的抗辐射作用.方法 将小鼠分为空白对照组、模型对照组及羊栖菜多糖复方制剂低[0.692g/(kg·d)]、中[2.075g/(kg·d)]、高[4.150g/(kg·d)]3个剂量组,以方格星虫提取物为阳性对照组,每天灌胃给药1次,灌胃2周后用60Co γ射线进行1次全身照射.测定小鼠外周血白细胞(WBC)、血小板和血细胞计数,以及脾指数(TI)、胸腺指数(SI)、骨髓有核细胞计数(BMWC)、血清超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量等指标.结果 3个剂量组小鼠与模型组比较,WBC均有上升趋势,但仅中剂量组在照后第14天与模型组差异有统计学意义(P<0.05).3个剂量组TI均明显高于模型组(P<0.05),SI和BMNC仅中、高剂量组明显高于模型组(P<0.05),SOD低、中剂量组明显高于模型组(P<0.05),MDA中、高剂量组低于模型组(P<0.05或P<0.01).结论 羊栖菜多糖复方制剂能有效提高小鼠的抗辐射能力.  相似文献   
89.
目的评价术中输注氨基酸对硬膜外阻滞复合全麻食管癌和贲门癌手术患者围术期深部体温和代谢的影响。方法择期食管癌和贲门癌手术患者21例,ASAⅠ或Ⅱ级,随机分为3组(n =7):从麻醉诱导开始至手术结束,分别静脉输注氨基酸混合液240kJ·h-1(AA组)、等容量乳酸钠林格氏液(LR组)、葡萄糖溶液240kJ·h-1(GLU组)。麻醉诱导前至术后2h每5分钟测定鼓膜温度,于麻醉诱导前即刻、手术开始后1h和术后1h检测指尖血糖,采用4分表法评价术后2h内寒战的发生情况,采用间接测热仪测定术前与术后氧耗。结果与麻醉诱导前即刻比较,术后30min LR组和GLU组氧耗降低,AA组氧耗升高(P<0.01),术后2h LR组、GLU组鼓膜温度降低(P<0.05),AA组差异无统计学意义(P>0.05);与LR组和GLU组比较,AA组术后2h内寒战发生例数减少(P< 0.05),术后30min氧耗增多(P<0.05),LR组与GLU组比较差异无统计学意义(P>0.05)。结论硬膜外阻滞复合全麻开胸手术患者术中静脉输注氨基酸可通过提高基础代谢率,缓解围术期深部体温降低,减少术后寒战发生,而输注葡萄糖不产生此效应。  相似文献   
90.
目的:观察残杀威对德国小蠊的药效。方法:采用果酱瓶药膜法和现场试验评价效果。结果残杀威对德国小蠊敏感品系的平均KT50为13.86min,现场品系8个调查点的KT50为11.25—38.02min,对抗氯菊酯品系KT50为16.06-23.37min,72h死亡率均为100%;现场试验,4周后的杀灭率仍达90.58%。结论:残杀威对德国小蠊现场品系为一般击倒;对抗氯菊酯品系尚未形成交互抗性,其水乳剂防制舰艇蜚蠊效果满意。  相似文献   
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