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71.
72.
Objectives
The current study aimed to assess ethanol-wet dentine surfaces by atomic force microscopy (AFM), and to evaluate the efficacy of ethanol-wet bonding on root dentine by determining the shear bond strength (SBS) and interfacial nanoleakage expression.Methods
Flat dentine slices from human premolar roots were randomly grouped into five. All specimens were acid-etched, rinsed, and left moist. They were then treated with 100% ethanol for 0 s (control group), 20 s (Group 1), 60 s (Group 2), three 60 s periods (Group 3), or stepwise ethanol application (Group 4). After treatment, each group was bonded either with Adper™ Scotchbond™ Multi-Purpose (Scotchbond) or experimental hydrophobic adhesive. Nano-scale adhesion forces (Fad) were probed by AFM and analysed using one-way ANOVA. The SBS results were analysed using two-way ANOVA. Tukey's test was employed for multiple comparisons.Results
Ethanol-wet protocols significantly decreased the value of Fad (p < 0.001). When bonded with Scotchbond, ethanol treatment did not affect the bond strength (p > 0.05), but decreased the interfacial nanoleakage. The SBS values of the groups bonded with hydrophobic adhesive varied with different ethanol-wet protocols (p < 0.05). Decreased nanoleakage was manifested in all experimental groups, except Group 1. Compared with the classical water-wet bonding with Scotchbond in the control group, Group 4 bonded with hydrophobic adhesive exhibited a significantly higher bond strength (p < 0.05).Conclusions
Ethanol-wet bonding using a stepwise ethanol application protocol may have potential benefits in the root dentine bonding of hydrophobic adhesive. 相似文献73.
利用SWOT理论分析疫情防控期间教学医院开展在线教学的内外部竞争环境和竞争条件。在综合性大学附属某医院开展临床医学课程在线教学,具有资源优势、组织优势和平台优势;但也存在临床医学专业的课程特殊性、临床教学医院的教师身份特殊性、疫情防控背景下在线教学的软硬件特殊性等劣势;为医院对标国家一流课程建设、发挥课程思政在教学阵地的主作用、营造主动型学习生态圈提供了发展基础;也对未来教学模式、教学管理模式、教学空间变革提出了挑战。基于此,提出推进医院医学教育信息化建设;全面提升教师信息素养;筑构适应于医院管理环境的教育信息化平台;搭建基于智慧教学空间的多元评价体系;基于多学科建设线上线下混合式课程体系等措施,以推进医院医学教育信息化建设和提升教学管理效率,促进“新医科”建设。 相似文献
74.
75.
目的:验证二甲双胍治疗抗精神病药引起的血脂异常的疗效和安全性。方法:将两项随机、安慰剂的
对照研究纳入分析。共有201例服用抗精神病药物后出现血脂异常的首发精神分裂症患者,并将其分为1 000 mg/d
二甲双胍组(以下简称为二甲双胍组,n=103)和安慰剂组(n=98),观察24周。在基线、治疗后第12周和第24周进行
临床症状及体重、血糖、血脂等代谢指标的评估。结果:二甲双胍治疗后,二甲双胍组和安慰剂组之间低密度脂
蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)的平均差异从基线时的0.16 mmol/L,降低到第24周结束时的
–0.86 mmol/L,降低了1.02 mmol/L,差异有统计学意义(P<0.01)。而24周结束时,二甲双胍组LDL-C≥3.37 mmol/L的
患者有25.3%,显著低于安慰剂组24周结束时的64.8%(P<0.01)。与安慰剂组相比,二甲双胍组的体重、体重指数、
胰岛素、胰岛素抵抗指数、总胆固醇、三酰甘油和高密度脂蛋白胆固醇也有显著变化,差异均有统计学意义(均
P<0.05)。治疗对体重和胰岛素抵抗的影响出现在第12周,并且在第24周进一步改善,但对改善血脂异常的作用在第
24周结束时才出现。结论:二甲双胍治疗对于改善抗精神病药物引起的血脂异常和胰岛素抵抗是有效的,并且改善
抗精神病药物诱导的胰岛素抵抗出现的时间早于降低血脂异常的时间。 相似文献
76.
【摘要】 目的 收集1例典型结节性硬化症患者的临床资料并检测其致病基因变异。方法 收集患者临床资料,应用二代测序法对患者进行致病基因筛查,采用Sanger测序法验证,构建迷你基因质粒转染至人肾上皮细胞系293T细胞,提取RNA进行转录分析。结果 患者临床表型包括反复癫痫发作,伴面部血管纤维瘤、甲周纤维瘤、肺淋巴管肌瘤病、肾血管平滑肌脂肪瘤及多发性骨质硬化。二代测序提示患者TSC2基因存在可疑致病变异,经Sanger测序验证,患者TSC2基因第4号外显子存在c.336_336+15delGGTAAGGCCCAGGGCG杂合突变,其父母及100名无关健康对照未检测出该位点变异。该突变位点既往未见报道。迷你基因实验显示,患者TSC2基因mRNA序列发生改变,原4号外显子剪切位点丢失,插入74 bp内含子序列,使剪切位置后移90 bp(r.336delins336+16_336+90)。结论 TSC2基因第4号外显子c.336_336+15delGGTAAGGCCCAGGGCG杂合变异可导致异常剪切,可能是该结节性硬化症患者病因。 相似文献
77.
Xin-Li Ouyang Bo-Yu Chen Yong-Fang Xie Yi-De Wu Shao-Jia Guo Xiao-Yun Dong Guo-Hui Wang 《国际眼科》2020,13(8):1210-1222
AIM: To investigate the risk factors for eye removal following ocular trauma at a major ophthalmology department in China. METHODS: A retrospective study of patients who underwent eye removal surgery following ocular trauma was completed. Clinical outcomes were consulted in detail through the hospital’s computed medical data system. Patients’ information including age, gender, cause of ocular trauma, affected eye, and education level was collected and recorded in a standardized database. Chi-squared test, Student’s t-test, Fisher’s exact test, and bivariate correlation analysis were used for statistical comparisons. RESULTS: The present study included 1675 removal eyes from 1674 patients over the 20-year period. Patients included 80.5% males and 19.5% females, with mean age of 38y. The majority of the patients (70.7%) were blue-collar workers (physical laborers), and 1098 patients (65.6%) did not receive high school education. Work-related injuries were the most common reason for eye removal (n=739, 44.1%), of which 441 cases (59.7%) were related to metal/nail wounds. The most frequent injury type in males was work-related injuries (49.7%), whereas the most frequent injury type in females was home-related injuries (25.8%). CONCLUSION: Work-related injuries were a leading cause of severe ocular injury resulting in eye removal. In addition, men and undereducated patients were more likely to undergo eye removal surgery following ocular trauma. This study identified multiple high-risk factors leading to eye removal following ocular trauma, which is of great importance for preventing severe eye injuries. 相似文献
78.
Rationale:Intravenous leiomyomatosis (IVL) is a rare and special type of smooth muscle tumor originating in the uterus. It is classified as a benign disease according to its histological features but shows the behavioral characteristics of a malignant tumor. It is easily misdiagnosed and recurrent. The purpose of this study was to retrospectively analyze clinicopathological data of 25 cases of IVL in order to enhance clinicians’ understanding of this rare disease.Patient concerns:We screened and identified 25 cases of IVL at our hospital from October 2013 to January 2020. Five patients had tumors.Diagnoses:The diagnosis in each case was pathologically confirmed after surgical treatment.Interventions:All patients were managed surgically. Although the surgical procedures were different, the surgical approach was geared towards achieving complete excision. Three patients received hormonal therapy with gonadotropinreleasing hormone agonists after surgery.Outcomes:We retrospectively reviewed all medical records and analyzed the clinicopathologic features and clinical outcomes of this disease as well as the correlations between the clinical features and risk of recurrence. Neither the symptoms nor the preoperative imaging results were suggestive of IVL in any of the cases. Except for two patients who were lost to follow-up, twenty-three patients who were followed up are still alive. Three patients experienced a recurrence.Lessons:The clinical manifestations and ultrasound images of IVL in the early stages are not typical; thus, IVL is easily misdiagnosed as uterine leiomyoma. Radiologists, pathologists, and surgeons should have a thorough understanding of IVL and a high index of vigilance for IVL in clinical practice. Surgery should always be aimed at achieving complete tumor excision. Patients with large lesions (≥7 cm) and lesions extending to the broad ligament may have an increased risk of recurrence. Early detection, diagnosis, and treatment are very important; once the diagnosis is confirmed, regular follow-ups are crucial. 相似文献
79.
80.
Although unstable angina can be initially controlled with medical therapy in most patients, there is a high incidence of subsequent death, myocardial infarction, or need for coronary bypass surgery to control symptoms. Identification at the time of presentation of the patient likely to do poorly on continued medical therapy would be useful in advising consideration of surgical therapy. Since coronary arterial spasm may have a significant role in the pathophysiology of unstable angina in some patients, the recently developed calcium channel antagonists may therefore be of particular benefit in the medical therapy of unstable angina. One hundred thirty-eight patients were entered into a randomized double-blind study of the efficacy of adding nifedipine to conventional treatment of unstable angina (nitrates and beta-blockers) and were followed for 18 months. Of these patients, 104 underwent coronary arteriography. A multivariate Cox's hazard function analysis was applied to variables selected from the history, electrocardiographic (ECG) changes during chest pain, and from scintigraphic and coronary arteriographic data to determine those variables most predictive of response to medical therapy. The percentage of the left ventricular myocardium supplied by vessels with 70% or greater luminal stenosis was the most significant variable in influencing failure of medical therapy defined as sudden death, myocardial infarction, or need for bypass surgery. Whether or not the patient received nifedipine was the second most powerful variable, with the use of nifedipine reducing by half the relative risk of failing medical therapy. These were followed by cigarette smoking and presence of global ST segment changes during ischemia. After 18 months the nifedipine group had fewer patients failing medical therapy (p = .02), with fewer patients undergoing coronary bypass surgery (p less than .01). However, nifedipine did not appear to have a preventive effect against myocardial infarction or death. Kaplan-Meier actuarial curves confirmed that medical therapy was significantly less successful in the presence of increasing numbers of significantly stenotic vessels (p = .03). However, nifedipine provided a significant beneficial effect in patients with two or more stenotic vessels (p less than .01) and in whom 50% or more of the myocardium was supplied by vessels with 70% or greater stenosis (p = .01). Thus, although patients with advanced obstructive coronary disease have the greatest likelihood of unfavorable outcomes, the addition of nifedipine is of significant benefit.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献