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IntroductionSome improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments.MethodsThe mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°–40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test.ResultsNiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P < .05). There was no significant difference between NiTi rotary system groups at any levels (P > .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P < .05).ConclusionsGT Series X and Twisted File rotary systems produced with innovative process were concluded to shape the curved canals to result in minimal canal transportation, similar to Revo-S, RaCe, Mtwo, and ProTaper Universal rotary systems manufactured by traditional methods. 相似文献
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Mehmet Odabasi Cengiz Eris Mehmet Kamil Yildiz Hasan Abuoglu Sami Akbulut Abdullah Saglam 《International surgery》2013,98(3):277-281
Hepatic artery aneurysms are responsible for 12% to 20% of all visceral arterial aneurysms. Because most patients are asymptomatic, this disease is generally diagnosed incidentally during radiologic examination. Aneurysm rupture develops in 14% to 80% of cases, depending on the aneurysmatic segment''s diameter and location, as well as other etiologic factors. Mortality rates associated with rupture range between 20% and 70%. Thus, early diagnosis and timely initiation of medical interventions are critical to improve survival rates. Here, we present a male patient, age 69 years, with a hepatic artery aneurysm that was detected incidentally. The 3-cm aneurysm was detected on contrast-enhanced computed tomography and extended from the common hepatic artery to the hepatic trifurcation. A laparotomy was performed using a right subcostal incision. After dissection of the hepatoduodenal ligament, the common, right, and left hepatic arteries, as well as the gastroduodenal artery, were suspended separately. Then, the aneurysmatic hepatic artery segment was resected, and the gastroduodenal artery stump was ligated. An end-to-end anastomosis was formed between the left and common hepatic arteries, followed by an end-to-end anastomosis formed between the right hepatic artery and splenic artery using a splenic artery transposition graft. Postoperative follow-up examinations showed that both hepatic arterial circulations were good, and no splenic infraction had developed. 相似文献
96.
Suleyman Celebi Durdane Aksoy Betul Cevik Abdullah Yildiz Semiha Kurt Ali Ihsan Dokucu 《Journal of pediatric surgery》2013
Background
A prospective study was performed to evaluate the effect of inguinal hernia repairs on the genitofemoral nerve (GFN), and to compare postoperative electrophysiologic changes in the GFN of patients who had undergone either open or laparoscopic surgery.Methods
Seventy patients with a mean age of 6.48 ± 3.49 were enrolled in the study. Either open or laparoscopic techniques were used to operate on the patients' inguinal hernias. In all cases, bilateral GFN motor responses were investigated electrophysiologically using surface electrodes on three occasions: preoperatively, in the first month, and third month postoperatively. t-Tests were used to compare changes in the GFN.Results
Preoperative mean latency of the GFN in all groups was found to be significantly prolonged on the hernia side, compared with the non-hernia side (P = 0.01). Although no difference was observed in the latency levels of the GFN on the operated side at the preoperative and early postoperative stages, GFN latency levels decreased significantly in the late postoperative period in the laparoscopic group (P < 0.05). In the late postoperative period, amplitudes of GFN motor responses were significantly higher in the laparoscopic group than the open repair group (0.91 ± 0.11 mV and 0.57 ± 0.053 mV, respectively; P < 0.05).Conclusion
Preoperative prolonged latency of GFN on the hernia side is likely to occur due to the pressure on the nerve caused by the hernia mass. By surgically removing the hernia mass, this buildup of pressure is prevented, decreasing the latency of the GFN. The significantly higher motor response amplitudes and decreased latency in the late postoperative stage for the laparoscopic group may be due to the fact that this technique is less invasive. 相似文献97.
Abdulkadir Unsal Taner Basturk Yener Koc Tamer Sakacı Elbis Ahbap Aysim Ozagarı Ayşe Sinangil Arar Cüneyt Akgül Mustafa Sevınc 《International urology and nephrology》2013,45(6):1779-1783
Introduction
Sarcoidosis is a multi-system disorder characterized by non-caseating epithelioid granulomas in multiple organs. Renal involvement may usually occur as granulomatous interstitial nephritis, but renal failure is uncommon. We report a case of renal-limited sarcoidosis diagnosed by renal biopsy, associated with abnormal calcium metabolism.Case presentation
A 30-year-old Caucasian male presented with unexplained renal function impairment and hypercalcemia. The patient did not have any history of kidney disease, cough, skin rash, dysuria, hematuria or any other symptoms. Physical examination was unremarkable. Serum creatinine was 2.2 mg/dl and serum calcium was 11.5 mg/dl. Serum intact parathyroid hormone level (12 pg/mL) was decreased. Serum angiotensin-converting enzyme (ACE), 1,25-dihydroxyvitamin D (1,alpha-25 vit D) and pre-proparathyroid hormone (PTHrP) levels and urinary calcium excretion were all in normal range. The renal biopsy showed severe interstitial nephritis with non-caseating granuloma. The patient was treated with prednisone with starting dose of 1 mg/kg. After 2 months of prednisone therapy, serum creatinine decreased. However, because of continued of hypercalcemia unresponsive to low calcium diet and prednisone, chloroquine was prescribed. Six months after the onset, the patient's serum creatinine is stable at 1.30 mg/dl, serum calcium is 10.8 mg/dl, and serum ACE and 1,alpha-25 vit D levels are in normal range. He does not have any signs of extra-renal relapse.Conclusion
The mechanisms of abnormal calcium metabolism in this patient with renal-limited sarcoidosis are unclear. 相似文献98.
Kilickesmez KO Abaci O Kocas C Yildiz A Kaya A Okcun B Kucukoglu S 《Heart and vessels》2012,27(4):391-397
Predictors of aortic dilatation are not well described in patients with bicuspid aortic valves (BAV). This study sought to examine the relationship between proximal aortic dilatation and matrix metalloproteinase-9 (MMP-9) and alpha 1-antitrypsin (α1AT) levels in patients with BAV. All patients underwent echocardiography using a standard protocol, and aortic measurements were taken in end-diastole. We studied 82 patients with BAV and categorized them into two groups according to aortic dimensions corrected for body surface area and age. The plasma level of α1AT was routinely determined using a BN ProSpec analyzer (Siemens Healthcare Diagnostics, Marburg, Germany), and that of MMP-9 were determined by ELISA (RayBiotech Inc. Norcross, GA, USA). Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS; SPSS Inc., Chicago, IL, USA) software for Windows version 12. This study included patients with BAV with no or mild valvular impairment. There were no significant differences between groups in terms of gender, body surface area, associated hypertension, diabetes mellitus, hyperlipidemia, or smoking. The mean ascending aortic diameter was 4.38?±?0.5?mm in group 1 and 3.34?±?0.35?mm in group 2 (p?0.001). Plasma concentration of α1AT in patients with ascending aortic dilatation was significantly lower than that in the non-dilated group (1.32?±?0.27 and 1.49?±?0.25?g/l, respectively; p?=?0.005). However, no significant difference was found in the MMP-9 level between the two groups (336.49?±?233.11 and 336.39?±?268.072?pg/ml, respectively; p?=?0.96). We observed a significantly negative correlation between ascending aortic diameter and α1AT level (r?=?-0.300, p?=?0.006) and a positive correlation between ascending aortic diameter and age (r?=?0.413, p?0.001). No significant correlation was found between plasma MMP-9 concentration and ascending aortic diameter (r?=?-0.008, p?=?0.94). A multiple linear regression analysis was performed, including age, α1AT level, MMP-9 level, and left ventricular diastolic diameter. In this analysis, α1AT level and age were the independent predictors of aortic dilatation (p?=?0.03 and p?=?0.02, respectively). 相似文献
99.
Tamer A. Gheita Iman I. El-Gazzar Ghada Azkalany Hussein S. El-Fishawy Amr El-Faramawy 《The Egyptian Rheumatologist》2012,34(4):147-152
Aim of the workTo assess the high sensitivity C-reactive protein (hs-CRP level) in systemic lupus erythematosus (SLE) patients without cardiac involvement and find its relation with clinical and laboratory findings, disease activity, damage index and intima-media thickness (IMT).Patients and methodsForty-five female SLE patients were recruited in the present study without any cardiac involvement. History taking, examination and laboratory investigations were performed for patients. Disease activity was evaluated by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and damage by the Systemic Lupus International Collaborating Clinics (SLICC) index. Thirty age matched female healthy subjects were considered as a control group. hs-CRP was measured quantitatively by microplate immunoenzymometric assay and the IMT measured by ultrasonography.ResultsThe hs-CRP in the patients was significantly higher (4.84 ± 3.91 mg/l) compared to the control (1.74 ± 0.61 mg/l) (p < 0.001). The IMT in the patients was significantly increased (0.72 ± 0.37 mm) compared to the control (0.54 ± 0.15 mm) (p 0.004). There was no difference in the level of hs-CRP according to the presence or absence of clinical manifestations. However, it was significantly higher in those with positive DNA (5.71 ± 4.36 mg/L) compared to those with negative results (3.12 ± 1.97 mg/L) (p 0.009). There was a significant correlation of the hs-CRP level with the IMT (r 0.49, p 0.001) and SLEDAI (r 0.67, p < 0.001).ConclusionsThese findings suggest that SLE patients without traditional major cardiovascular risk factors may have increased risk of future cardiac events. Measuring hs-CRP may be useful as a marker of disease activity, increased IMT and subclinical atherosclerosis in SLE especially those with positive ds-DNA. 相似文献
100.