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61.
62.
Introduction
The aim of this study was to compare the effect of the EndoVac irrigation system (SybronEndo, Orange, CA) and conventional endodontic needle irrigation on sealer penetration into dentinal tubules.Methods
Forty single-rooted, recently extracted human maxillary central incisors were randomly divided into 2 groups according to the irrigation technique used: conventional endodontic needle irrigation and EndoVac irrigation. All teeth were instrumented using the ProFile rotary system (Dentsply Maillefer, Ballaigues, Switzerland) and obturated with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) labeled with fluorescent dye. Transverse sections at 1, 3, and 5 mm from the root apex were examined using confocal laser scanning microscopy. The total percentage and maximum depth of sealer penetration were then measured.Results
Mann-Whitney test results showed that EndoVac irrigation resulted in a significantly higher percentage of sealer penetration than conventional irrigation at both the 1- and 3-mm levels (P < .05). However, no difference was found at the 5-mm level. The 5-mm sections in each group showed a significantly higher percentage and maximum depth of sealer penetration than did the 1- and 3-mm sections (P < .05).Conclusions
The EndoVac irrigation system significantly improved the sealer penetration at the 1- to 3-mm level over that of conventional endodontic needle irrigation. 相似文献63.
The most common site of cerebrospinal fluid (CSF) leakage is through the floor of the anterior fossa, which communicates with the ethmoid or frontal sinuses or with the nasal fossa. The sphenoid sinus is rarely implicated as a source of spontaneous CSF fistula. Transclival meningocele is an extremely rare lesion. A 36-year-old woman with a 1-year history of intermittent CSF rhinorrhea was found to have a transclival meningocele. The diagnosis of transclival meningocele was made by magnetic resonance (MR), 3-dimension-computerized tomography (CT). At operation, by a transsphenoidal approach, the transclival meningocele was packed with fasia lata graft, fat tissue, and bio-glue. This is the third case of transsphenoidal transclival meningocele producing rhinorrhea in an adult. Transclival meningocele should be taken into consideration in patients with spontaneous CSF rhinorrhea. 相似文献
64.
Ozkan T Tuncer S Aydin A Hosbay Z Gulgonen A 《The Journal of hand surgery, European volume》2004,29(3):265-270
A brachioradialis muscle rerouting procedure was used to restore active supination in five children with cerebral palsy and a pronation deformity. Following release and lengthening of the pronator quadratus and pronator teres muscles, respectively, the brachioradialis tendon was divided as a Z plasty and the distal part of the tendon was passed through the interosseous space in a dorsal to palmar direction, and then sutured to its proximal end. The procedure resulted in a gain of 81 degrees of active supination. 相似文献
65.
Yavuz A Tuncer M Gürkan A Demirbaş A Süleymanlar G Ersoy F Yakupoğlu G 《Transplantation proceedings》2004,36(1):108-110
Cigarette smoking may adversely influence patient and graft survival. In Europe and the United States the prevalence of cigarette smoking in dialysis patients is 35% to 40% and 25%, respectively. In Turkey, the estimated prevalence of cigarette smoking rate in the normal population is 26%. This study evaluated the rate of smoking in 63 cadaveric, and 158 living-related renal transplant recipients including (150 men, and 76 women of 38 +/- 12 years; range, 8 to 70) who were operated between 1986 and 2001. Demographic data were collected with a questionnaire delivered to patients during their routine outpatient visits. During this time period, 8 patients had died, 4 from hemophagocytic syndrome, 2 from cardiovascular disease, 1 from Kaposi sarcoma and 1 from a cerebrovascular accident. Twenty-three patients have lost their grafts. While at the time of transplantation 97 (42%) were smoking cigarettes, only 29 (12%) continued smoke after transplantation. Male gender significantly correlated with cigarette smoking (P =.000). Twelve smokers were single but 85 out of 97 were married, a statistically significant difference (P =.010). In contrast there was no significant relationship between pretransplant smoking and educational status (P =.354); graft loss and smoking (P =.129); or mortality and smoking (P =.224). There was a significant relationship between pretransplant and posttransplant smoking (P =.000). There was no relationship between pre- and post-transplant smoking and development of diabetes mellitus or hypertension. Interestingly the posttransplant serum albumin level was lower among smokers than nonsmokers (4.44 +/- 0.02 g/dL vs 4.30 +/- 0.02 g/dL; P =.019). There was a close relationship between transplantation duration and smoking. 相似文献
66.
Kurt H Alioğlu C Karayazgan B Tuncer N Kılıçoğlu H 《European journal of orthodontics》2011,33(6):636-641
The aim of this research was to evaluate, within a controlled clinical study, the effects of a Delaire-type facemask or a modified Jasper Jumper (JJ) used in the treatment of children with Class III malocclusions due to maxillary retrognathia on temporomandibular disorders (TMDs). Forty-six patients with Class III malocclusions referred for orthodontic treatment were divided into two groups, a test and a control. The test group comprised 33 randomly chosen patients (15 females, 18 males) aged 8-11 years. The control group included 13 patients (eight females, five males) with similar features. TMD assessment was performed before and after treatment using a two-axis questionnaire, the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMDs). Qualitative data were evaluated using chi-square and McNemar tests. No statistically significant differences related to the presence of TMD were observed pre- or post-treatment (P > 0.05). The most commonly encountered diagnosis was arthralgia in the JJ group both before and after treatment. Evaluation of joint and muscle regions showed decreased symptoms, apart from the diagnosed discomforts, in the JJ group (P < 0.05). Reduced symptoms were observed in the Delaire group; however, this reduction was not statistically significant. An increase, not considered to be statistically significant, was observed in the control group. The Delaire-type facemask and modified JJ used in the early phase of Class III malocclusion treatment did not result in TMD. 相似文献
67.
Hyperhomocysteinemia is an independent risk factor for ischemic stroke. The enzyme methylenetetrahydrofolate reductase (MTHFR) plays a critical role in modulating the levels of plasma homocysteine. Two polymorphisms in the MTHFR gene, C677T, A1298C result in reduced enzyme activity. The mechanisms of ischemic and hemorrhagic stroke are not well understood. Although controversial, previous studies have shown evidence of causality of both stroke subtypes in patients with methylenetetrahydrofolate reductase gene polymorphisms. Therefore, we examined whether the C677T and A1298C polymorphisms of MTHFR gene are genetic risk factors for both ischemic and hemorrhagic stroke in a Turkish Caucasian population. In a case-control study, 120 total unrelated stroke patients (92 ischemic stroke, 28 hemorrhagic stroke), and 259 healthy controls were genotyped for C677T and A1298C polymorphisms of the MTHFR gene using a PCR-RFLP based-method. The MTHFR 1298C allele (chi(2)=8.589; P=0.014), C1298C genotype (OR=2.544; P=0.004), and C677C/C1298C compound genotype (OR=3.020; P=0.001) were associated with overall stroke. The MTHFR 1298C allele (chi(2)=11.166; P=0.004), C1298C genotype (OR=2.950; P=0.001), and C677C/C1298C compound genotype (OR=3.463, P=0.0001) were strongly associated with ischemic stroke. Interestingly however, the MTHFR 677T allele (chi(2)=6.033; P=0.049), T677T genotype (OR=3.120; P=0.014), and T677T/A1298A compound genotype (OR=4.211; P=0.002) were associated with hemorrhagic stroke. In conclusion, the C677T and A1298C polymorphisms of the MTHFR gene are genetic risk factors for hamorrhagic and ischemic stroke respectively, independent of other atherothrombotic risk factors. 相似文献
68.
69.
70.
The aim of this study was to identify the effects of adding quercetin (Q) to Tris extender in order to identify levels of oxidative stress in bull sperm after freeze thawing. Ejaculates were collected via artificial vagina from Holstein bulls. Semen was divided into five tools and diluted to a final concentration of 15 × 106 spermatozoa/ml with the Tris extender containing Q (25, 50, 100 and 200 μg/ml) and no additive (control; C). All examples were equilibrated at 4°C during 4 hr then were loaded into 0.25‐ml straws and frozen using a controlled rate. Sperm motility and motility characteristics were determined using the computer‐assisted semen analyser. Sperm membrane integrity was assessed using the hypoosmotic swelling test. Sperm chromatin integrity was investigated using the single cell gel electrophoresis. Total antioxidant capacities were performed colorimetrically. Q supplementation used as an antioxidant did not produce better results in the proportion of sperm progressive and total motility, plasma membrane integrity and sperm abnormalities. Q supplementation exhibited the favourable tail length, tail DNA and tail moment. In conclusion, when whole parameters are considered, Q25 can be added to the Tris extender due to its positive effect on sperm DNA integrity and no adverse effect on the progressive and total motilities of sperm. 相似文献