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排序方式: 共有956条查询结果,搜索用时 991 毫秒
1.
目的 检测不同浓度微酸性次氯酸水(slightly acidic hypochlorite water,SAHW)应用于口腔综合治疗台水路(dental unit waterlines,DUWLs)的消毒效果。方法    选取32台口腔综合治疗台(dental chair unit,DCU),随机均分为4组(1个对照组和3个实验组,每组8台DCU)。首先,采集高速手机和三用枪基础水样行细菌培养、菌落计数;然后,实验组分别用有效氯含量8 ~ 12 mg/L(实验1组)、18 ~ 22 mg/L(实验2组)、28 ~ 32 mg/L(实验3组)的SAHW供水DUWLs,连续7 d采集高速手机和三用枪水样行细菌培养、菌落计数。第8 d始改用无菌蒸馏水(distilled water,DW)供水DUWLs后采集水样菌落培养计数;对照组用DW替代消毒水,同样程序流动冲洗DUWLs后收集高速手机和三用枪水样菌培养后菌落计数。数据采用SPSS 20.0软件进行统计分析。结果    与基础水样比较,SAHW消毒1 d,3个实验组的高速手机和三用枪水样菌落计数均显著下降(P < 0.05);SAHW消毒2 d,实验3组高速手机和三用枪水样菌落计数均小于消毒合格水样上限值(100 CFU/mL);SAHW消毒3 d开始,实验3组菌落计数为0 CFU/mL,实验1组和2组菌落计数均显著小于100 CFU/mL。更换为DW供水后1 ~ 2 d,3个实验组的高速手机和三用枪水样菌落计数维持小于100 CFU/mL,组间差异无统计学意义(P > 0.05);3 ~ 7 d,3个实验组的高速手机和三用枪水样菌落计数持续增加(149 ~ 1014 CFU/mL),实验1、2、3组的组内不同时间点检测数据比较差异均有统计学意义(均P < 0.05),且均明显大于合格水样上限值(P < 0.05)。结论    高有效氯含量较低有效氯含量的SAHW消毒效果更稳定;低有效氯含量8 ~ 12 mg/L的SAHW持续作用于DUWLs内环境亦可有效控制菌落计数,消毒效果明显。  相似文献   
2.
New tooth-colored restorative materials have been developed with the goal of replacing amalgam. These restoratives are marketed as packable composite and ormocer. The purpose of the present study was to compare the compressive shear bond strengths of these new materials with that of hybrid composite and amalgam as core materials. Standardized core buildups were made on four groups of extracted molars, with 10 teeth per group. Three tooth-colored restorative materials (Filtek Z 250, Filtek P 60, and Definite) and an amalgam (SDI Permite) were used. Specimens were placed in a special jig at a 45-degree angle. The compressive shear bond strength was obtained using a universal testing machine. The Kruskal-Wallis test was used to compare the groups, and pairwise comparisons were made by Mann-Whitney U test (P < .05). Filtek P 60, a packable composite resin, had the greatest compressive shear bond strength values in all instances, and the ormocer (Definite) had the lowest. The strengths of packable composite, hybrid composite, and amalgam as core materials were not significantly different (P > .05).  相似文献   
3.
This study compared the cuspal fracture resistance of posterior teeth restored with four different adhesive restorations. Fifty sound, maxillary human premolars were randomly divided into a control group and four experimental groups with 10 teeth in each. Specimens in the first group were intact teeth that were tested as unprepared. The remaining four groups received mesio-oclusodistal cavity preparations and were restored with a hybrid composite (Filtek Z250), a packable composite (Filtek P60), an ormocer (Definite) and an amalgam (SDI Permite) with an amalgam bonding agent (Amalgam Bond Plus). All groups were stored in water at 37 degrees C for 15 days and thermocycled 1000 times between 5 degrees-55 degrees C. The specimens were preloaded five times in compression to 10 kg using two metal rods that contacted only the teeth on the cuspal inclines. The teeth were then loaded occlusally in an Instron Universal Testing Machine until fracture occurred. The means of force required to fracture the teeth in each of the five groups was analyzed using one-way ANOVA and Tukey Test. The difference between the mean cuspal fracture resistance of the unprepared control teeth and those restored with amalgam groups was found to be statistically significant (p < 0.05). No significant differences in resistance to cuspal fracture were found among the restoration groups, the unprepared control group and those teeth restored with hybrid composite, packable composite and ormocer groups (p > 0.05).  相似文献   
4.
目的 探讨孤立性髂动脉瘤介入治疗的临床经验。方法 回顾性分析2010年1月至2018年9月昆明医科大学附属延安医院血管介入科采用覆膜支架介入治疗孤立性髂动脉瘤39例,术后3个月、6个月及之后的每年对病人进行随访,探讨相关治疗方法。结果 39例病人分型有1A:Ⅰ型1例,1B:Ⅱ型8例,1D:Ⅳ型17例,2B:Ⅱ型2例,2D:Ⅳ型1例,2E:V型10例。平均瘤体最大直径为(42.4±11.2)mm(23.0~77.0 mm)。39例病人均顺利完成介入手术治疗,技术成功率100%,术中保留双侧髂内动脉1例,保留一侧髂内动脉29例,双侧髂内动脉均封闭9例,术中行一侧髂内动脉栓塞9例,行双侧髂内动脉均栓塞1例,手术时间为(49.0±17.0)min(35.0~87.0 min),术后随访(31.9±17.7)个月(5~69个月),术后除1例左髂动脉瘤破裂且合并肾衰竭的病人死亡,其余病人均好转出院,复查CTA示髂动脉瘤被完全封闭,支架形态位置良好,无内漏及其他并发症。结论 孤立性髂动脉瘤起病隐匿,早期多无症状,CT等检查能够早期诊断。介入治疗是安全有效的方法。应注意在术前根据髂动脉瘤的累及范围,近远端有无足够的锚定区进行分型,并对不同分型进行有差别的个体化治疗。  相似文献   
5.
目的报告泌尿道子宫内膜异位症的手术治疗效果以及探讨保守型手术和根治性手术的选择。方法对5个手术科室参与的输尿管或膀胱深部浸润型子宫内膜异位症外科治疗的CIRENDO前瞻性数据库管理数据进行回顾性研究。对术前、术中和术后数据结果进行分析。结果数据库中的数据显示,30例中有15例为输尿管子宫内膜异位症,14例为膀胱结节病变(bladder nodules),1例同时存在这2种类型的病变。输尿管松解术14例,其中输尿管完全恢复解剖解构10例。4例40岁以上的患者术后出现闭经和可忍受的中度输尿管狭窄,其中3例好转,1例行二次输尿管切除和输尿管膀胱吻合术。4例初次手术行输尿管切除术。5例输尿管标本中发现2例输尿管子宫内膜异位症。4例并发症中有2例与输尿管结节病灶切除有关,2例与膀胱子宫内膜异位病灶切除有关。远期效果较为满意,如疼痛症状显著改善、泌尿系不适症状消失,仅有1例较长时间膀胱神经功能障碍。结论建议保守性手术联合术后假绝经疗法治疗大多数泌尿道子宫内膜异位症。尽管总体结果满意,由于术中可能同时施行其他一些复杂手术如结直肠手术,术后并发症的风险仍不容忽视。  相似文献   
6.
Osteofibrous dysplasia is a rare and benign disease that originates from the tibia or fibula. The symptoms of osteofibrous dysplasia include painless enlargement and bowing of the tibia and pain occurring in the presence of pathological fracture. Herein a male infant who was admitted with redness and swelling on the right leg and diagnosed as pathological tibia fracture due to left tibia osteofibrous dysplasia on the third day of life was presented. To our knowledge, this is the earliest presentation of osteofibrous dysplasia with a pathological fracture in a neonate. Therefore, it must be suspected in neonatal bone fractures.  相似文献   
7.
8.
Ataturk Dam Lake, the largest impounded lake in Turkey, has been contaminated by domestic, industrial and agricultural effluents coming from Adiyaman city. In this study, we investigated the possible effects of pollutants on several biochemical parameters in the cyprinid fish, Cyprinus carpio, by comparing the parameters in fish collected from a polluted area (Sitilce) to a relatively clean area (Samsat) in August 2011. The activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and lactate dehydrogenase and levels of cortisol, glucose, and K increased while total protein, cholesterol, Ca, Na and Cl levels decreased in fish from the Sitilce site when compared to the Samsat site. The observed alterations in these biochemical parameters indicate that the Ataturk Dam Lake is affected by untreated wastewater discharges.  相似文献   
9.
目的 建立习惯性打鼾患儿中重度阻塞性睡眠呼吸暂停(OSA)的临床预测模型,为临床诊疗提供依据。方法 选择2019年1月至12月就诊于首都医科大学附属北京儿童医院睡眠中心的3~12岁习惯性打鼾患儿。所有患儿完成一般资料收集、OSA-18问卷、PSQ-SRBD量表及多导睡眠监测。应用决策树方法构建重度OSA患儿的临床预测模型。结果 共纳入受试患儿1441例,根据PSG结果,重度OSA 1152例,非重度OSA 289例。重度OSA组年龄、男性比例、体重指数(BMI)、颈围/身高比、腹围/臀围比、SRBD量表呼吸维度、其他维度及总分均高于非重度OSA组(P均<0.01)。OSA-18问卷各个维度得分及总分在两组患儿间比较,差异无统计学意义(P均>0.05)。基于决策树构建的重度OSA患儿预测模型,对非重度OSA患儿预测精确率为90%,召回率76%,F1得分82%,对重度OSA患儿的预测精确率32%,召回率58%,F1得分41%,整体准确率为73%。 结论 该研究构建的重度OSA患儿临床预测模型整体准确率73%,有一定的预测价值,能为临床排除重度OSA患儿提供一定的依据,指导临床决策,但仍需更多的临床资料进一步优化模型。  相似文献   
10.
??Laparoscopic resection for gastric stromal tumor LI Zi-yu*, XING Zhao-dong, WANG Jing, et al. *Department of Gastrointestinal Surgery, Peking University Cancer Hospital & Institute, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education of China), Beijing 100142, China
Corresponding author: LI Zi-yu, E-mail: ligregory@outlook.com
Abstract Objective To evaluate the indication and safety of laparoscopic resection for gastric stromal tumor.??Methods The clinical data of 58 cases of GIST performed laparoscopic gastric resection (LR) and 99 cases performed open gastric resection (OR) from July 2007 to September 2014 at Peking University Cancer Hospital and Institute were compared retrospectively. Results Compared with the OR group, the LR group showed no significant difference in postoperative hospital stay [8.5 d vs. 8.9 d, P=0.684] and operation time [118 min vs. 110 min, P=0.272]. However, the bleeding volume in the LR group was less [37 mL vs. 66 mL, P=0.000], incision length was shorter [5.1 cm vs. 15.7 cm, P=0.000], and tumor size was smaller [3.9 cm vs. 5.5 cm??P=0.000]. No severe complications such as bleeding and leakage were found in both groups. Median follow up time in the LR group and the OR group was 29 months and 36 months respectively. During the period, no recurrence was detected in the LR group, while recurrence was found in two cases of high risk in the OR group. Conclusion Laparoscopic resection is safe, feasible and minimally invasive for the small gastric stromal tumor and can get the same therapeutic effect as OR.  相似文献   
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