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1.
《Dental materials》2020,36(1):119-134
ObjectiveThe aim of this systematic review and meta-analysis was to evaluate the effect of surface conditioning methods on the bond strength of industrial indirect composite blocks (ICs).MethodsBased on the PICOS strategy, the Medline via PubMed, Embase and Web of Science (ISI – Web of Knowledge) electronic databases were searched for peer-reviewed articles in both English and Chinese, with no publication year limit. In vitro studies evaluating the effects of surface conditioning on the bond strength of ICs were selected. The meta-analysis was conducted to calculate the mean difference between surface-conditioned ICs and unconditioned controls. Subgroup analysis was performed to evaluate the different surface conditioning methods, separately for polymer-infiltrated ceramic network (PICN) material and the ICs with dispersed fillers (ICDFs). Meta-analyses were performed with a random-effects model at a significance level of 0.05.Results and SignificanceFrom 802 relevant studies, 25 were selected for full-text analysis. Nineteen studies were eligible for inclusion in this systematic review, whereas 9 studies were included in the meta-analysis. A manual search of the principal periodicals specific to the area resulted in no additional articles. The meta-analysis indicated a significant difference in bond strength between the surface-conditioned ICs and controls under both non-aged and aged conditions. The combination of mechanical and chemical conditioning yielded the highest bond strength of ICs. This meta-analysis suggests that chemical etching followed by a universal primer and alumina air abrasion followed by a silane coupling agent could be considered the best strategy for optimizing the bond strength of PICN materials and ICDFs under aged conditions, respectively.  相似文献   
2.
While decreasing trend in gender differences in alcohol use disorders was reported in Western countries, the change in Asian countries is unknown. This study aims to explore the shifts in gender difference in alcohol abuse (AA) and dependence (AD) in Korea. We compared the data from two nation-wide community surveys to evaluate gender differences in lifetime AA and AD by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Face-to-face interviews using the Composite International Diagnostic Interview (CIDI) were applied to all subjects in 2001 (n=6,220) and 2011 (n=6,022). Male-to-female ratio of odds was decreased from 6.41 (95% CI, 4.81-8.54) to 4.37 (95% CI, 3.35-5.71) for AA and from 3.75 (95% CI, 2.96-4.75) to 2.40 (95% CI, 1.80-3.19) for AD. Among those aged 18-29, gender gap even became statistically insignificant for AA (OR, 1.59; 95% CI, 0.97-2.63) and AD (OR, 1.18; 95% CI, 0.80-2.41) in 2011. Men generally showed decreased odds for AD (0.55; 95% CI, 0.45-0.67) and women aged 30-39 showed increased odds for AA (2.13; 95% CI 1.18-3.84) in 2011 compared to 2001. Decreased AD in men and increased AA in women seem to contribute to the decrease of gender gap. Increased risk for AA in young women suggests needs for interventions.  相似文献   
3.
异体甘油保存皮与自体微粒皮复合移植的临床应用   总被引:1,自引:0,他引:1  
目的:寻找深度大面积\烧伤的早期治疗方法。方法:大面积深度烧伤于4-5天即行切痂,以异体甘油皮为支架,将有限的自体皮制作成微粒皮后均匀地复合植于创面。结果:对5例共12个肢体2个躯干进行早期切痂后异体甘油皮+自体微粒皮的复合移植,成活后的创面平堤,外观平整,颜色淡红或近拟正常皮肤,触饮,收缩少,结论:异体甘油保存皮+自体微粒皮复合移植是大面积深度烧伤较理想的治疗方法。  相似文献   
4.
5.
碳纤维根管桩的研制   总被引:1,自引:0,他引:1  
目的研究高强度碳纤维增强复合树脂根管桩的加工成型工艺.方法用湿法制备碳纤维预浸料,在预成型模具中预成型,然后在成型模具中经特殊的工艺进行成型,最后用车床加工成预定形状的桩钉;并测试其弯曲强度、剪切强度和碳纤维含量.结果随着碳纤维含量的增加,根管桩的弯曲强度和剪切强度均逐渐增加.碳纤维含量达到67.13%时,弯曲强度和剪切强度分别达到406MPa和653.86MPa.结论高强度的碳纤维根管桩可以满足临床需要.  相似文献   
6.
目的探讨复方丹参注射液联合干扰素治疗慢性乙肝患者的疗效。方法110例慢性乙肝患者,按随机方法分成①对照组30例,应用普通保肝药物治疗,疗程6个月;②丹参组30例,应用复方丹参注射液(每ml含丹参、降香各1g)30ml加入10%葡萄糖溶液300ml中静脉注射1个月;③IFN组30例,应用IFN—α 3MU,隔日一次肌内注射,3个月;④联合组20例,应用复方丹参注射液30ml加10%葡萄糖溶液300ml静脉注射1个月,IFN-α 3MU,隔日一次肌内注射,3个月。丹参组,IFN组和联合组保肝药物治疗同对照组。四组病例在性别、年龄、病程,治疗前肝功能等方面均无统计学差异。治疗前检测肝功能,肝炎病毒标志,血清HA、IV—C、PCI—Ⅱ,部分病例进行肝穿病理检查。治疗开始后每月检测肝功能,3个月(治疗后)和6个月(随访时)时检测血清HA、IV—C、PCⅢ及乙肝病毒标志,治疗后1年行肝穿病理检查。结果治疗前四组患者血清HA、PCⅢ、IV—C水平无统计学差异;治疗后丹参组、IFN组、联合组血清HA、FCⅢ、IV—C水平较治疗前及对照组有不同程度的降低。结论复方丹参注射液联合IFN治疗可使血清HA、PCⅢ、IV—C有明显下降,肝组织病理改变明显改善,为目前有效的慢性乙肝治疗措施。  相似文献   
7.
复合带瓣人工血管替换升主动脉和主动脉瓣(24例报告)   总被引:1,自引:0,他引:1  
报告24例升主动脉瘤伴主动脉瓣关闭不全行升主动脉和主动脉瓣替换及冠状动脉开口移植术(Bental术22例,底盘法2例)。13例伴有升主动脉夹层分离,对其中8例DeBakeyI型者,以Teflon毡条内外加固主动脉切端后吻合。13例用人工血管周围间隙与右心耳吻合以控制升主动脉吻合之外的出血。3例以人工血管片环包主动脉吻合口控制局部广泛渗血及出血。2例术毕不能脱离体外循环死亡,手术死亡率83%。随访平均218个月,2例死于蛛网膜下腔出血,1例右股动脉栓塞经手术治愈;其余病人康复良好,心功能(NYHA)I~II级。  相似文献   
8.
Objective To discuss the clinical characteristics and management principles of com-posite pheochromoeytoma of adrenal gland (pheochromocytoma-ganglioneuroma). Methods Four cases of composite tumor of adrenal gland diagnosed pathologically were reviewed. All the cases were male, aged 37 to 62 years;three of them had the history of hypertension, one of them accompanied with paroxysmal palpitation, while one case was asymptomatic. Computerized tomography and ultra-sonography showed single tumor in adrenal, the diameter was about 2.5、3.8、6.3、15cm respectively. Two cases showed positive results in 131Ⅰ-metaiodobenzylguanidine (MIBG) scintigraphy. One case showed positive result in 99Tcm-hydrazinonicotinamide-3trysinoctreotide (HTOC) scintigraphy. Twenty-four hours urinary catecholamine examination revealed the average of norepinephrine, epi-nephrine and dopamine were (196.1±92.2)nmol/24 h, (26.6±8.9)nmol/24 h, (1957.9±913.5) nmol/24 h respectively. Two cases were at a little elevated level and the others with normal. All cases were managed with α-adrenergic receptor blocker preoperatively for 2-4 weeks. Results Tumor re-section was performed in all 4 cases, and 3 cases by retroperitoneal laparoscopy, one by open surgery. All 4 cases were diagnosed as composite pheochromocytoma of adrenal (Pheochromocytoma-gangli-oneuroma) by pathology. All patients had no evidence of recurrence or metastasis during follow-up from 15 to 38 months. Two of three cases with hypertension reverted to normotensive. Conclusions Composite pheochromocytoma of adrenal is rare, difficult to be diagnosed preoperatively. Except mild in eatecholamine secretion, which clinical manifestations are similar to pheochromocytoma. Pheochro-mocytoma-ganglioneuroma is no apparent tendency for aggressive behaviors, the results of surgical management are favorable.  相似文献   
9.
目的:对银背风毛菊(Saussmea nivea Turcz)全草化学成分进行研究、方法:用硅胶色谱技术对化合物进行分离,用化学及光谱方法对化合物结构进行鉴定。结果:从银背风毛葡全草的乙醇提取物中分离得到5个化合物.经化学方法及光谱技术(UV,IR,^1HNMR,^13CNMR)分别鉴定其为:山奈素(kaempferol Ⅰ),槲皮素(quercetinl Ⅱ),α-树脂醇(α-amyrin Ⅲ),α-香树酯醇乙酸酸(α-amyrin acetate Ⅳ),胡萝卜苷(daucosterol Ⅴ)。结论:化合物Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ系首次从该植物中得到。  相似文献   
10.
During the past 20 years, numerous techniques have been described to improve the results of facelifting as well as the duration of its rejuvenating effect. These increasingly aggressive techniques have increased the operating time, the potential morbidity of the operation, and the duration of convalescence. No one can ensure that this evolution in sophistication of rhytidectomy techniques give longer lasting results. Therefore, a simple technique applied under the appropriate indications gives good and predictable results.  相似文献   
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