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11.
考察光固化、化学固化两种固化方式对封闭剂性能的影响。从粘结性能看,粘度值相近,树脂突长度无显著差异,但抗剪粘结强度光固化优于化学固化。在机械性能上,自制材料表面硬度、径向抗张强度光固化高于化学固化,在抗压强度上两者差异不大(P>0.05),但Concise材料结果与此相反,原因有待进一步研究,吸水性和磨耗率都是光固化小。总体评价,光固化实验室性能优于化学固化。  相似文献   
12.
根尖切除术中不同器械对于根尖倒预备的影响   总被引:7,自引:0,他引:7  
目的比较根尖切除术中传统慢速手机与超声器械对于根尖倒预备的不同影响。方法借助扫描电镜对48颗离体前磨牙进行观察研究,使用AutoCAD2005制图软件辅助计算。结果使用传统慢速手机进行根尖倒预备后的牙根硬组织最小厚度(均值0.15mm)明显低于使用超声器械(S129D均值0.82mm,S129均值0.76mm),具有统计学显著意义(P<0.05)。结论使用超声器械进行根尖倒预备可以有效的保护牙根硬组织,保持牙根的强度。  相似文献   
13.
Radiotherapy for the nasopharyngeal cancer patient with poor oral care may lead to severe deterioration of the dentition and may require multiple extractions. Although the use of an implant-retained overdenture can successfully restore the function and esthetics of edentulous patients, its use can be complicated by the tissue changes subsequent to head and neck irradiation. The difficulties in implant treatment planning for an edentulous patient with macroglossia and soft tissue changes following radiotherapy are discussed.  相似文献   
14.
Sucrose metabolism of dental plaque which accumulated in fissure-like spaces between small bovine enamel cubes on removable U-shaped appliances was analysed using radiolabelled techniques. The appliances were worn by 8 dental students for 21 days. Half of the fissural inserts (3) on one wing of the appliance were exposed to a 10 per cent sucrose solution in normal saline and half (3) to normal saline as a control on the opposite wing, 8 x/day. At 21 days [14C]-sucrose (U) was applied directly to sucrose and saline-exposed inserts extra-orally for 60 min at 37 degrees C (non-dispersed plaques, NDP). Adjacent inserts on both sides of the appliances were removed. The plaque was dispersed in buffer by sonication, cultured and was exposed to radiolabelled sucrose for the same incubation period (dispersed plaques, DP). The following observations were made: (1) quantitative values for sucrose consumption and lactic acid, cell-bound and insoluble product, soluble polysaccharide, carbon dioxide and total volatile acid formation did not differ between sucrose and saline exposed DP or sucrose- and saline-exposed NDP; (2) all DP consumed more sucrose and formed higher quantitative levels of all products than NDP counterparts, p less than 0.001; (3) sucrose-exposed DP and sucrose exposed NDP formed proportionally more lactic acid than saline-exposed counterparts, p less than 0.05; (4) sucrose-exposed NDP formed proportionally more lactic acid and less soluble polysaccharide than sucrose exposed DP, p less than 0.025; (5) concentrations of lactobacilli were higher in sucrose exposed plaques, p less than 0.049.  相似文献   
15.
The use of craniofacial implants to assist in retaining auricular prostheses often requires complex laboratory procedures, involving production of an accurate casting, fitting of a precious alloy bar, and the use of clips. A simplified method for the retention of an auricular prosthesis with a composite bar and magnets is described in this article.  相似文献   
16.

Background

Dyslipidemia, a risk factor for cardiovascular disease (CVD), is more prevalent in middle-aged women than in men of the same age in Korea. This study, the first national survey that focused on cholesterol in Korean women, aimed to: (1) assess their awareness and knowledge of cholesterol, (2) evaluate their risk reduction behavior, and (3) examine differences in these variables among geographical regions in Korea.

Methods

A questionnaire survey study was conducted in a randomly selected national sample of 1304 Korean women, aged 40-64 years in 3 geographic regions.

Results

High cholesterol was identified as a cause of CVD by 54.4% of respondents, however, 95.4% did not know their own values. Only 4.1% of respondents were aware of desirable level of total cholesterol. Eight percent of respondents perceived correctly the meaning of high-density lipoprotein cholesterol (HDL-C) as good cholesterol. And 32.9% had cholesterol check at least once a year. No significant regional differences were found in women's awareness and knowledge on cholesterol. No smoking (93.6%), low salt diet (52.5%) and weight management (50.6%) were the most prevalent risk reduction behaviors. Women in the rural area performed less risk reduction behaviors than those in urban area.

Conclusions

Given the low level of awareness and knowledge about cholesterol in these women, nurses need to increase their education about cholesterol and risk reduction behaviors of CVD for middle-aged Korean women, particularly those in rural area. To resolve identified disparities in women's risk reduction behaviors between the rural and urban area, a national-level health policy can result in a successful effort to promote women's awareness of cholesterol and risk reduction behaviors for the cardiovascular health of the public.  相似文献   
17.
18.
Activation of microglial NADPH oxidase (NOX2) plays a critical role in mediating neuroinflammation, which is closely linked with the pathogenesis of a variety of neurodegenerative diseases, including Parkinson's disease (PD). The inhibition of NOX2‐generated superoxide has become an effective strategy for developing disease‐modifying therapies for PD. However, the lack of specific and potent NOX2 inhibitors has hampered the progress of this approach. Diphenyleneiodonium (DPI) is a widely used, long‐acting NOX2 inhibitor. However, due to its non‐specificity for NOX2 and high cytotoxicity at standard doses (µM), DPI has been precluded from human studies. In this study, using ultra‐low doses of DPI, we aimed to: (1) investigate whether these problems could be circumvented and (2) determine whether ultra‐low doses of DPI were able to preserve its utility as a potent NOX2 inhibitor. We found that DPI at subpicomolar concentrations (10?14 and 10?13 M) displays no toxicity in primary midbrain neuron‐glia cultures. More importantly, we observed that subpicomolar DPI inhibited phorbol myristate acetate (PMA)‐induced activation of NOX2. The same concentrations of DPI did not inhibit the activities of a series of flavoprotein‐containing enzymes. Furthermore, potent neuroprotective efficacy was demonstrated in a post‐treatment study. When subpicomolar DPI was added to neuron‐glia cultures pretreated with lipopolysaccharide, 1‐methyl‐4‐phenylpyridinium or rotenone, it potently protected the dopaminergic neurons. In summary, DPI's unique combination of high specificity toward NOX2, low cytotoxicity and potent neuroprotective efficacy in post‐treatment regimens suggests that subpicomolar DPI may be an ideal candidate for further animal studies and potential clinical trials. GLIA 2014;62:2034–2043  相似文献   
19.

Background

Despite recent advances in preoperative diagnostic imaging and operative techniques, biliary variation of the donor still remains a challenge in the procurement of graft. The supraportal right bile duct (BD) variant including presentation as trifurcation is a potential trap for injuring the remnant bile duct of donor.

Methods

Before living/related-donor liver transplantation (LRLT), cholangiogram with magnetic resonance images of each donor was performed as a routine. After exploration of the donor before hilar dissection, intraoperative chloangiography (IOC) was routinely performed. Among the supraportal right bile duct variants, if the preoperative cholangiography showed a suspected trifurcation of the bile duct, we then performed 3 sessions of IOC during liver graft procurement, including prior to hilar dissection, before the division of bile ducts and after the division. We reviewed the cholangiogram and the postoperative laboratory data of a consecutive series of 25 donors of LRLT.

Results

There was no division injury of the remnant bile duct of all of the donors.

Conclusions

Repeated IOC is suggested as a routine for variants of supraportal right bile ducts especially trifurcation pattern in graft procurement to avoid the injury of donor remnant bile ducts.  相似文献   
20.

Background

The incidence of obesity is increasing both in the general population and in incident dialysis patients. While there is evidence that being overweight is associated with good outcomes in hemodialysis, the evidence in peritoneal dialysis (PD) patients is not very clear. We studied a modern cohort of PD patients to examine outcomes in large patients.

Methods

Forty-three patients who started PD, who weighed more than 90 kg at dialysis initiation, between January/2000 and June/2010 were matched with 43 control patients who weighed less than 90 kg. Detailed review of the charts was undertaken.

Results

The mean weight and body mass index of the wt < 90 kg group were 69.3 ± 11.3 kg and 25.0 ± 3.9 kg/m2. The number of peritonitis episodes per year was 0.33 ± 0.6 (wt < 90 kg) and 0.82 ± 1.7 (wt ≥ 90 kg) (p = 0.26). The median time to first peritonitis showed a trend toward earlier peritonitis in larger patients [9.5 (4.3, 27) months in wt ≥ 90 kg, 19.1(7.9, 30.8) months in wt < 90 kg] but did not reach statistical significance (p = 0.12). Surprisingly, hernias and leaks were more common in the weight <90 kg group (44 vs. 18.6 % p = 0.02). There was no difference in total number of hospitalizations or the number of days hospitalized. Kaplan–Meier analysis of survival on PD showed no differences between the two groups (logrank p = 0.99). Cox regression analysis using age, race, cause of ESRD due to diabetes and Charlson comorbidity index as the covariates did not show weight to be associated with survival on PD.

Conclusions

Large patients tend to do just as well on PD, with survival on PD being no different compared to individuals with lower weight and body mass index.  相似文献   
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