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51.

Introduction

Near-infrared diode lasers can be used for several applications, which range from disinfection to smear layer removal in endodontics. This study evaluated the efficacy of agitation of 15% EDTA with an 808-nm diode laser on removal of the smear layer.

Methods

Sixty extracted human maxillary central incisor teeth were instrumented up to ProTaper F4 (Dentsply Maillefer, Ballagues, Switzerland) and then randomly divided into 6 groups (n = 10 for each group) according to the different final irrigating protocols as follows: 5% sodium hypochlorite for 120 seconds performed with the NaviTip (Dentsply Maillefer, Ballaigues, Switzerland) (control group); 15% EDTA for 120 seconds performed with the NaviTip; and agitation of 15% EDTA with an 808-nm diode laser for 10, 20, 30, and 40 seconds. Specimens were observed under a scanning electron microscope, and open dentinal tubules were counted using Adobe Photoshop software (Adobe Systems, San Jose, CA). The data were analyzed with 1-way analysis of variance and Tukey post hoc tests (P = .05).

Results

The number of open dentinal tubules was higher in the middle thirds than in the apical thirds. The differences between the apical and middle thirds were statistically significant (P < .05). Statistically significant differences were also found between the control group and the other groups in both the middle and apical thirds of the root canals (P < .05).

Conclusions

The results indicated that agitation of 15% EDTA with an 808-nm diode laser for 20 seconds was effective in removing the smear layer in the apical thirds of root canals.  相似文献   
52.
The purpose of this study was to evaluate the influence of different surface treatments (sandblasting, acid etching, and laser irradiation) on the shear bond strength of lithium disilicate-based core (IPS Empress 2) and feldspathic ceramics (VITA VM 9). One hundred ceramic discs were divided into two groups of 50 discs each for two ceramic systems: IPS Empress 2 (group I) and VITA VM 9 (group II). Each of the two groups was further divided into five surface treatment groups (ten each) as follows: group SB, sandblasting with alumina particles (50 μm); group HF, 5 % hydrofluoric acid etching; group L, Er:YAG laser irradiation (distance, 1 mm; 500 mJ; 20 Hz; 10 W; manually, noncontact R14 handpiece); group SB–L, sandblasting + Er:YAG laser; and group HF–L, 5 % hydrofluoric acid + Er:YAG laser. Luting cement (Panavia 2.0) was bonded to the ceramic specimens using Teflon tubes. After 24 h of water storage, a shear bond strength test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed with a two-way analysis of variance (ANOVA) and Tukey's honestly significant difference tests (α?=?0.05). The two-way ANOVA indicated that the shear bond strength was significantly affected by the surface treatment methods (p?<?0.05), but there was no significant interaction between the ceramic systems. Group SB–L had the highest mean values for each ceramic system. Sandblasting, followed by Er:YAG laser irradiation, enhanced the bond strength, indicating its potential use as an alternative method. The atomic force microscopic evaluation revealed that group SB had the most distinct sharp peaks among the groups.  相似文献   
53.
To assess maternal serum and cord blood apelin-36 and nesfatin-1 concentrations in pregnant women with and without gestational diabetes mellitus (GDM). Thirty pregnant women with GDM and 30 gestational age matched healthy pregnant subjects participated to the study. Maternal serum and cord blood nesfatin-1 and apelin-36 levels were measured with ELISA, at the time of birth. The relationships between maternal serum and cord blood nesfatin-1 and apelin-36 levels, anthropometric and metabolic parameters were also assessed. Maternal serum apelin-36 levels were found higher (13.5?±?8.3 vs. 9.6?±?5.9?ng/ml, P?=?0.001) and nesfatin-1 levels were found lower (5.5?±?8.1 vs. 8.1?±?23.9?ng/ml, P?=?0.001) in patients with GDM compared with control pregnant women. However, the cord blood apelin-36 levels (8.8?±?4.3 and 8.2?±?1.9?ng/ml, P?=?0.618) and nesfatin-1 levels (5.4?±?4.0 and 6.2?±?10.3?ng/ml, P?=?0.688) were similar in the GDM and control groups, respectively. Maternal serum apelin-36 and nesfatin-1 levels correlated positively with their respective cord blood levels. Maternal serum and cord blood apelin-36 levels correlated negatively with the gestational age and birth weight. Similarly maternal serum and cord blood nesfatin-1 levels correlated negatively with the gestational age, but there was no correlation with the birth weight. We did not find a correlation between maternal serum apelin-36 and nesfatin-1 levels, maternal age, BMI, fasting glucose, fasting insulin, and HOMA-IR. Also cord blood apelin-36 and nesfatin-1 levels did not correlate with the maternal age, BMI, HOMA-IR, cord blood glucose, and cord blood insulin levels. Our results indicate that apelin-36 concentrations increase and nesfatin-1 concentrations decrease in maternal serum of women with GDM.  相似文献   
54.
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Sustaining hemostasis in clinical hemorrhages is a challenging task and requires extensive effort to stabilize medically hard-to-treat traumatic injuries. Several hemostatic agents are preferred to control external and internal bleedings, yet commercially available products are not sufficiently effective or fast-acting to achieve hemostasis in extreme cases. Ankaferd Blood Stopper (ABS) is a herbal extract traditionally used as a hemostatic agent. Recent studies have shown that ABS could be utilized successfully as a hemostatic agent for the management of clinical hemorrhages when conventional methods were ineffective. This review serves as a basis to provide recent findings on several applications of ABS, specifically preclinical, biological, and clinical studies both in vitro and in vivo. Another section focuses on the ultrastructural morphology and protein network formation of ABS in an effort to understand the hemostatic mechanisms of this unique agent at tissue level.  相似文献   
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Objective: The aim of this study was to determine the frequency of HLA DR-DQ haplotypes in children with type 1 diabetes mellitus (T1DM) in the Southeast Region of Turkey.Methods: Eighty children and adolescents with T1DM and eighty control subjects participated in the study. HLA-DR, DQ was typed using polymerase chain reaction and sequence-specific priming technique.Results: HLA DRB1*03 allele was significantly more common in patients than in control subjects. HLA DRB1*11, HLA DRB1*13 and HLA DRB1*14 allele frequencies were significantly lower in patients than in controls. DQB1*02 allele was more common in patients, whereas DQB1*03 allele was more frequent in control subjects. HLA DRB1*03-DQB1*02 haplotype was more frequently observed among patients.Conclusion: These results confirm the similar potential trends in the frequency distribution of HLA susceptibility genes with T1DM previously observed in Turkey and in other Caucasian populations. Conflict of interest:None declared.  相似文献   
59.
Hypothalamic obesity is an intractable form of obesity syndrome that was initially described in patients with hypothalamic tumours and surgical damage. However, this definition is now expanded to include obesity developing after a variety of insults, including intracranial infections, infiltrations, trauma, vascular problems and hydrocephalus, in addition to acquired or congenital functional defects in central energy homeostasis in children with the so‐called common obesity. The pathogenetic mechanisms underlying hypothalamic obesity are complex and multifactorial. Weight gain results from damage to the ventromedial hypothalamus, which leads, variously, to hyperphagia, a low‐resting metabolic rate; autonomic imbalance; growth hormone‐, gonadotropins and thyroid‐stimulating hormone deficiency; hypomobility; and insomnia. Hypothalamic obesity did not receive enough attention, as evidenced by rarity of studies in this group of patients. A satellite symposium was held during the European Congress of Obesity in May 2011, in Istanbul, Turkey, to discuss recent developments and concepts regarding pathophysiology and management of hypothalamic obesity in children. An international group of leading researchers presented certain aspects of the problem. This paper summarizes the highlights of this symposium. Understanding the central role of the hypothalamus in the regulation of feeding and energy metabolism will help us gain insights into the pathogenesis and management of common obesity.  相似文献   
60.

Purpose

The aim of this study was to evaluate the effect of breast magnetic resonance imaging (MRI) on preoperative or intraoperative surgical planning.

Methods

One hundred and sixty females with breast cancer were enrolled in the study. The contribution of MRI compared to MMG and USG, their histopathological concordance, and their impact on surgical treatment were evaluated prospectively.

Results

In 48 (30.0%) of the patients, MRI identified suspicious lesions that were not detected by MMG and USG. The diagnosis by MRI was accurate in 17 (10.6%) of them, while in remaining 31 patients (19.4%) the additional lesions found by MRI and interpreted as malignant were found not to be malignant. The pathological accordance of MRI and MMG compared with USG were 69.3 and 70.0%, respectively, whereas individually, MMG and USG were in accordance with the pathological examination in 52.9 and 67.9% of the cases, respectively.

Conclusions

Assessment of the tumor size, multifocality, multicentricity, and presence of ductal carcinoma in situ by MRI may lead to misinterpretations in the majority of patients. The surgical approach should not be changed based solely on MRI findings. An accurately interpreted MMG combined with USG may be sufficient in most cases.  相似文献   
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