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81.
In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries. Cl atoms and ClOx (x = 2, 3 or 4) groups, confirmed by X-ray photoelectron spectroscopy analysis, were covalently doped into the graphene powder network to increase the defect density in the graphene framework and improve the electrochemical performance of Li-ion batteries. The microscopic properties of the Cl-doped graphene powder were investigated by scanning electron microscopy and transmission electron microscopy (TEM) analyses. TEM analysis showed that the one-layer thickness of the graphene was approximately 0.33 nm. Raman spectroscopy analysis was carried out to determine the defect density of the graphene structures. The G peak obtained in the Raman spectra is related to the formation of sp2 hybridized carbons in the graphene-based powders. The 2D peak seen in the spectra shows that the synthesized graphene-based powders have optically transparent structures. In addition, the number of sp2 hybridized carbon rings was calculated to be 22, 19, and 38 for the Cl-GP1, Cl-GP2, and Cl-GOP samples, respectively. As a result of the charge/discharge tests of the electrodes as anodes in Li-ion batteries, Cl-GP2 exhibits the best electrochemical performance of 493 mA h g−1 at a charge/discharge current density of 50 mA g−1.

In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries.  相似文献   
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Carcinoma of the fourth part of the duodenum: Report of a case   总被引:1,自引:0,他引:1  
Primary carcinoma of the duodenum is rare, accounting for only 0.35% of all gastrointestinal carcinomas, and carcinoma of the fourth part of the duodenum constitutes approximately 10% of duodenal carcinomas. Since the predominant symptoms of tumors in this part of duodenum are related to upper intestinal obstruction, the diagnosis is usually made late. We report the case of a 66-year-old man who presented with anemia, weight loss, and upper intestinal obstruction, and was found to have advanced primary carcinoma of the fourth part of the duodenum by upper gastrointestinal series and computed tomography (CT). A review of the literature indicates that survival, which is related to nodal status, the grade of the tumor, and surgical results, seems to be longer in patients with carcinoma in this part of the duodenum compared to those with carcinomas in other parts of the duodenum. Moreover, segmentary resection has been reported to achieve a favorable outcome.  相似文献   
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Background

After receiving a living donor liver transplant (LDLT), an incisional hernia is a potentially serious complication that can affect the patient’s quality of life. In the present study we evaluated surgical hernia repair after LDLT.

Materials and methods

Medical records of patients who underwent surgery to repair an incisional hernia after LDLT in Turgut Ozal Medical Center between October 2006 and January 2010 were evaluated in this retrospective study. A reverse-T incision was made for liver transplantation. The hernias were repaired with onlay polypropylene mesh. Age, gender, post-transplant relaparatomy, the type, the result of surgery for the incisional hernia, and risk factors for developing incisional hernia were evaluated.

Results

An incisional hernia developed in 44 of 173 (25.4 %) patients after LDLT. Incisional hernia repair was performed in 14 of 173 patients (8.1 %) who underwent LDLT from October 2006 to January 2010. Relaparatomy was associated with incisional hernia (p = 0.0002). The mean age at the time of the incisional hernia repair was 51 years, and 79 % of the patients were men. The median follow-up period was 19.2 (13–36) months after the hernia repair. Three patients with intestinal incarceration underwent emergency surgery to repair the hernia. Partial small bowel resection was required in one patient. Postoperative complications included seroma formation in one patient and wound infection in another. There was no recurrence of hernia during the follow-up period.

Conclusions

The incidence of incisional hernia after LDLT was 25.4 % in this study. Relaparatomy increases the probability of developing incisional hernia in recipients of LDLT. According to the results of the study, repair of an incisional hernia with onlay mesh is a suitable option.  相似文献   
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We report a case of an abdominal aortic embolism due to rupture of a cardiac hydatid cyst. This report emphasizes the diagnostic, preventative, and treatment options for hydatid cyst embolism of abdominal aorta. Echocardiography should be routinely performed in all patients with hydatid disease for possible involvement of the heart. This enables early diagnosis and treatment of cardiac echinococcus before life-threatening complications occur.  相似文献   
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Abstract Hybrid repair of an acute type B aortic dissection with endovascular stenting and aortic arch debranching is an acceptable treatment in complicated type B dissection. We present the case of a 71‐year‐old man presenting with acute type B aortic dissection and concomitant aneurysm of the distal aortic arch, who underwent an uneventful hybrid procedure, which involved subclavian‐to‐subclavian bypass before endovascular stent‐graft placement to the aortic arch. (J Card Surg 2010;25:336‐339)  相似文献   
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IntroductionPrevious studies have shown that carbon monoxide, which is endogenously produced, is increased in community-acquired pneumonia (CAP). However, it has not been studied enough whether severity of pneumonia is correlated with increased carboxyhemoglobin (COHb) concentrations in CAP. The aim of this study was to determine whether endogenous carbon monoxide levels in patients with CAP were higher compared with the control group and, if so, to determine whether COHb concentrations could predict severity in CAP.Materials and methodsEighty-two patients with CAP were evaluated in this cross-sectional study during a 10-month period. Demographic data, pneumonia severity index and confusion, uremia, rate respiratory, pressure blood, age>65 (CURB-65) scores, hospital admission or discharge decisions, and 30-day hospital mortality rate were recorded. In addition, 83 control subjects were included to study. The COHb concentration was measured in arterial blood sample.ResultsThe levels of COHb in patients with CAP were 1.70% (minimum-maximum, 0.8-3.2), whereas those in control subjects, 1.40% (minimum-maximum, 0.8-2.9). The higher COHb concentrations in patients with CAP were statistically significant (P < .05). Concentration of COHb correlated with pneumonia severity index (P = .04, r = 0.187); however, it did not correlate with CURB-65 (P = .218, r = 0.112).ConclusionAlthough COHb concentrations show an increase in patients with pneumonia, it was concluded that this increase did not act as an indicator in diagnosis process or prediction of clinical severity for the physicians.  相似文献   
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