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1.
Gerard Wieczkowski Jr. D.D.S.Xin Yi Yu MM. †Robert B. Joynt D.D.S. †Elaine L. Davis Ph. D. † 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》1992,4(2):37-40
Marginal leakage in amalgam restorations often precedes the development of secondary caries. One potential way to improve the marginal seal of such restorations, and thus minimize the risk of carles development, is to apply a glassionomer base prior to amalgam placement.
This study compared microleakage resistance among amalgam restorations placed with and without light-cured glass-ionomer base materials. Preparations were made in extracted human molar teeth. Four groups were studied, including copal varnish, which was used as a control. All specimens were restored with amalgam. Results indicated significantly greater leakage at the cavity wall/base interface for restorations with a copal varnish cavity liner than for those with a glass-ionomer base. Leakage differences among bases were also found at the amalgam/base interface. Best results were obtained with a dual-cure resin-based system. These samples showed minimal leakage at both the cavity wall/base and the base/amalgam interfaces. These findings suggest that light-cured glass-ionomer bases can be effective in the prevention of microleakage in amalgam restorations. 相似文献
This study compared microleakage resistance among amalgam restorations placed with and without light-cured glass-ionomer base materials. Preparations were made in extracted human molar teeth. Four groups were studied, including copal varnish, which was used as a control. All specimens were restored with amalgam. Results indicated significantly greater leakage at the cavity wall/base interface for restorations with a copal varnish cavity liner than for those with a glass-ionomer base. Leakage differences among bases were also found at the amalgam/base interface. Best results were obtained with a dual-cure resin-based system. These samples showed minimal leakage at both the cavity wall/base and the base/amalgam interfaces. These findings suggest that light-cured glass-ionomer bases can be effective in the prevention of microleakage in amalgam restorations. 相似文献
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F. Wang MClinEpid FRACS A. J. Gill MD FRACP M. Neale MM FRACS V. Puttaswamy MBBS FRACS S. Gananadha MS FRACS N. Pavlakis PhD FRACP S. Clarke MD FRACP T. J. Hugh MD FRACS J. S. Samra DPhil FRACS 《Annals of surgical oncology》2014,21(6):1937-1947
Background
Although pancreatoduodenectomy (PD) with mesenterico-portal vein resection (VR) can be performed safely in patients with resectable pancreatic ductal adenocarcinoma (PDAC), the impact of this approach on long-term survival is controversial.Patients and Methods
Analyses of a prospectively collected database revealed 122 consecutive patients with PDAC who underwent PD with (PD+VR) or without (PD?VR) VR between January 2004 and May 2012. Clinical data, operative results, and survival outcomes were analysed.Results
Sixty-four (53 %) patients underwent PD+VR. The majority (84 %) of the venous reconstructions were performed with a primary end-to-end anastomosis. Demographic and postoperative outcomes were similar between the two groups. American Society of Anesthesiologists (ASA) score, duration of operation, intraoperative blood loss, and blood transfusion requirement were significantly greater in the PD+VR group compared with the PD?VR group. Furthermore, the tumor size was larger, and the rates of periuncinate neural invasion and positive resection margin were higher in the PD+VR group compared with the PD?VR group. Histological venous involvement occurred in 47 of 62 (76 %) patients in the PD+VR group. At a median follow-up of 29 months, the median overall survival (OS) was 18 months for the PD+VR group, and 31 months for the PD?VR group (p = 0.016). ASA score, lymph node metastasis, neurovascular invasion, and tumor differentiation were predictive of survival. The need for VR in itself was not prognostic of survival.Conclusions
PD with VR has similar morbidity but worse OS compared with a PD?VR. Although VR is not predictive of survival, tumors requiring a PD+VR have more adverse biological features. 相似文献3.
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MB Soudarssanane S Mathanraj MM Sumanth Ajit Sahai M Karthigeyan 《Indian Journal of Community Medicine》2008,33(2):107-112
Background:
Early diagnosis of hypertension (HT) is an important strategy in its control. Tracking of blood pressure (BP) has been found useful in identifying persons with potential HT, particularly in youngsters. A cohort of 756 subjects (with baseline information as a cross-sectional study in 2002) was followed up in 2006 to comment on the distribution of BP and its attributes.Objectives:
To track BP distribution in a cohort of adolescents and young adults, and assess the persistence of high/low normotensives; to measure the incidence of HT and study the relationship of BP with age, sex, socioeconomic status, BMI, physical exercise, salt intake, smoking and alcohol consumption.Materials and Methods:
The baseline study cohort (2002) of 756 subjects (19-24 years) in urban field area of Department of Preventive and Social Medicine, JIPMER, was followed up between May and November 2006 by house visits for measurement of sociodemographic variables, anthropometry, salt intake, physical activity and BP.Results:
A total of 555 subjects from the 2002 cohort were contacted (73.4%), in that 54.5% subjects who were below 5th percentile, 93.6% subjects between 5th and 95th percentiles and 72% of those above 95th percentile previously persisted in the same cut-offs for systolic blood pressure (SBP). The corresponding figures for diastolic blood pressure (DBP) were 46.2, 92.2 and 74.1%, respectively. Shift from one cut-off to another was not significant for both SBP and DBP, proving the tracking phenomenon. Annual incidence of HT was 9.8/1000. Baseline BP was the significant predictor of current BP for the entire cohort; BMI and salt intake were significant predictors only in certain sections of the study cohort.Conclusions:
Early diagnosis of hypertension even among adolescents/young adults is an important preventive measure, as tracking exists in the population. 相似文献8.
Incidence and determinants of moderate COPD (GOLD II) in male smokers aged 40–65 years: 5-year follow up 下载免费PDF全文
Roeland MM Geijer Alfred PE Sachs Theo JM Verheij Philippe L Salom Jan-Willem J Lammers Arno W Hoes 《The British journal of general practice》2006,56(530):656-661
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD. 相似文献
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