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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.
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
83.
目的观察日光和年龄对皮肤弹性的影响。方法问卷调查受试者(郊县组94例,市区组105例)的日光曝晒情况,并应用皮肤弹性测量仪测量外眦部、鼻唇沟及眶下皮肤弹性参数,包括:弹性,黏弹性,可扩展性和张力参数。比较不同年龄组间、市区与郊县组间各弹性参数间的差异。结果市区和郊县各弹性参数均与年龄有较好的相关性,随年龄增长,皮肤各弹性参数均下降。郊县组与市区组比较,弹性和黏弹性参数差异较小,而可扩展性和张力参数差异较大。结论弹性和黏弹性参数可能与内在老化有关,而可扩展性和张力参数可能与光老化有关。 相似文献
84.
目的 利用地理信息系统 (GIS)技术分析中国大陆肾综合征出血热 (HFRS)的空间区域分布 ,建立HFRS危险区域分布图。方法 收集中国 41个HFRS监测点 1 995~ 1 998年的人群发病资料建立数据库 ,以中国省级、县级、一级河流数字地图为背景 ,在ArcGIS软件的支持下 ,与建立的数据库关联并对监测点人群发病资料进行反距离权重插值分析 ;收集 1 998年 6月SPOT4卫星覆盖东南亚地区的植被影像 ,逐一提取出各监测点监测区域的归一化植被指数 (NDVI) ,与 1 995~ 1 998年HFRS监测点人群平均发病率进行相关分析 ;根据不同流行强度监测区域的NDVI值 ,对遥感影像使用不同的颜色进行密度分割。结果 HFRS监测点人群发病资料的空间分析预测模型显示 ,中国HFRS主要分布于黑龙江流域、黄河中下游地区、长江中下游地区及京杭大运河 淮河流域地区 ,与1 995~ 1 998年全国各县HFRS平均发病率分布图进行比较 ,发现两者基本一致 ;相关分析显示HFRS发病率与NDVI之间呈现正相关 (r=0 .41 7,P <0 .0 1 ) ,根据各监测点NDVI的差异建立了中国HFRS危险区域分布图。结论 根据监测点数据采用GIS技术建立的预测模型对预测全国HFRS的分布情况有重要意义 相似文献
85.
急性脑梗死后血浆NO、NOS、ET含量的动态变化及尼莫地平对其影响 总被引:4,自引:0,他引:4
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
86.
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
87.
肿瘤浸润性淋巴细胞(TIL)经白细胞介素2(IL-2)体外培养后具有很强的体内外抗肿瘤作用,且有一定的靶细胞特异性,其抗肿瘤效果强于淋巴因子激活的杀伤细胞即LAK细胞(P<0.01)。从瘤体中新鲜分离到的TIL对自体肿瘤细胞的杀伤活性极低,经IL-2体外培养后,其杀伤活性逐渐增高,以培养至7~25d的杀伤活性最强,这与IL-2使TIL分泌3种抗癌淋巴因子包括IL-2、IFN-γ、淋巴毒素(LT)增加有关。体外培养25d后,TIL的抗肿瘤活性下降,实验表明这与培养过程中TIL的Lyt-2~+细胞(Tc)减少而L3T4~+细胞(T_H)增多有关。TIL经冻存复苏和IL-2体外培养后仍保持很强的抗肿瘤活性,冻存前后比较未见显著差异(P>0.05),这为间断地运用TIL治疗复发性、晚期肿瘤提供了一条可行的途径。 相似文献
88.
法莫替丁冲剂在健康人中的生物利用度及药动学研究 总被引:1,自引:0,他引:1
本实验采用反相高效液相色谱法,比较了10名健康志愿者单剂量口服法莫替丁冲剂及等剂量片剂的生物利用度。结果表明:二种剂型的Tmax,Cmax,AUC均无显著性差异(P〉0.05)。冲剂相对于与片剂的相对生物利用度F=101.90。 相似文献
89.
Wang Tao Liang Zhihou Sun Shenggang Cao Xuebing Peng Hai Cao Fei Liu Hongjin Tong E-tang 《华中科技大学学报(医学英德文版)》2003,23(2):145-147
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
90.
目的为了检测TPO的体内活性及其对血小板减少的治疗作用,寻找用以治疗辐射及化学药物等所致骨髓损伤造成的血小板减少与缺乏,缓解临床上的出血症状,降低死亡率的一种新途径。方法本实验应用基因工程的方法重组了人的TPO,取昆明种正常雄性,经一次5.0Gy60Coγ射线全身照射小白鼠为动物模型,通过对外周血血象的观察,及小鼠骨髓造血祖细胞培养的检测,研究了rhTPO在体内对60Co全身照射处理小鼠的造血系统的影响。结果实验表明,rhTPO能够减轻照射对小鼠外周血血小板及骨髓造血祖细胞中巨核系祖细胞的影响,并有促进其早期恢复的作用,且这种作用是量效相关的。结论提示,TPO是巨核细胞系统较特异的正调控因子,具有促进巨核细胞增殖发育和刺激血小板生成的作用,是临床治疗骨髓组织损伤引起的血小板减少和缺乏及贫血的有希望的生物治疗药物。 相似文献