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101.
Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu2Si monolayer. Pristine Cu2Si, a metallic monolayer, has a planar hexacoordinate structure. Calculations revealed that the most favorable position of a single H atom on the Cu2Si monolayer is at the top of a Si site. Derivatives of Cu2Si monolayer with various H concentrations were investigated, and by performing phonon calculations, it was found that there are three stable hydrogenated structures. Specific heat of these monolayers was found to increase with the hydrogen concentration at temperatures higher than 100 K. Electronically, the hydrogenated derivatives of Cu2Si monolayer preserve the metallic character.

Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu2Si monolayer.  相似文献   
102.
Therapeutic delays in cases of external incarcerated hernias typically result in increasing morbidity, mortality, and health expenditures. We investigated the diagnostic role of blood fibrinogen level, white blood count (WBC), mean platelet volume (MPV), and platelet distribution width (PDW) in patients with incarcerated hernia. Two groups, each containing 100 patients, were studied. Group A underwent elective, and group B underwent incarcerated and urgent external hernia repair. We observed high fibrinogen and WBC levels but low MPV and PDW values for patients in group B. Contrary to our expectations, we found lower MPV and PDW values in the complicated group than in the elective group. The morbidity rate and cost burden were higher in group B, and the results were statistically significant. Early operation should be recommended for patients with incarcerated external hernias if their fibrinogen and WBC levels are high.Key words: Incarcerated external hernia, Fibrinogen, Complete blood countExternal strangulated hernia is one of the most common causes of intestinal obstruction especially in the elderly. Delay in treatment may be dangerous.1 Andrews found that the need of bowel resection rate was 27% and the mortality rate was 21% when diagnosis was delayed more than 48 hours; whereas these rates were 7% and 1.4% when diagnosis was obtained in the first 24 hours.2 In addition to increased morbidity and mortality rates, a delay in the treatment of strangulated external hernias is associated with extended hospital stays and an increased need for intensive care, thereby resulting in increased health costs. Of course, clinical signs and symptoms are the most important evidences in diagnosis of incarcerated hernias. In order to make correct diagnosis, we also have powerful weapons such as radiologic imaging methods. However, these clinical and radiologic evidences show complications, especially intestinal perforation due to incarceration. Awareness of probable complications is essential. In this regard, we sometimes need simple methods to alert us. The white blood count (WBC), mean platelet volume (MPV), platelet distribution width (PDW), and blood fibrinogen level have been shown to be valuable predictive parameters for ischemic events in different parts of the body.39 There are probable ischemic tissues and organs in incarcerated hernia sac. So, in this study, we aimed to investigate the effectiveness of these simple blood tests in diagnosis. Generally, there is no problem in diagnosis, but sometimes the delay in treatment results in additional morbidity such as a need for bowel resection.  相似文献   
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Defunctioning stoma is a commonly used colorectal surgical procedures. The stomal complications recorded are usually classified as early and late complications. Parastomal hernia is a common complication of stomal surgery. We present a very rare stoma-related complication developed after parastomal hernia and described parastomal evisceration.  相似文献   
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An 83-year-old man presented with an unusually severe case of rhinophyma. Giant rhinopyhma is very rare in literature. The giant lesion was widely excised using sharp surgical incision and coblation assisted surgery. Using direct coblation to the nasal dorsum may cause edema in the surrounding tissue. There was minimal edema in surrounding tissue using this technique. A full thickness-skin graft was applied after excision. Cosmetic and functional postoperative results were satisfactory.KEY WORDS: Coblation, giant, rhinophyma  相似文献   
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Background

Variances in fibroblasts’ α2β1 integrin intensity may lead to altered adhesion to type I collagen and consequently to suppression of phagocytosis which may be one of the mechanisms for drug induced gingival overgrowth. The present study aimed to evaluate the genotype and allele frequencies of α2 integrin +807 gene in renal transplant patients with and without gingival overgrowth.

Material and methods

Seventy renal transplant patients with cyclosporine A (CsA)-induced gingival overgrowth (CsA GO+) were enrolled. Renal transplant patients without GO medicated with CsA (CsA GO−; n = 79) and tacrolimus (Tac; n = 52) served as controls. DNA was obtained from peripheral blood and ITGA2 +807C/T polymorphism was genotyped by polymerase chain reaction and restriction fragment length polymorphism method. Clinical parameters including probing depth and plaque, papilla bleeding and hyperplasia indexes were recorded. Chi-square, Kruskal–Wallis and Mann–Whitney tests were used in statistical analysis.

Results

Clinical parameters of CsA GO+ group were significantly higher than those of the CsA GO− and Tac groups (p < 0.05). ITGA2 807C/T genotype and allele frequencies of study groups were similar (p > 0.05).

Conclusion

Within the limits of the present study it can be concluded that ITGA2 +807 gene polymorphism is not associated with susceptibility to CsA-induced GO.  相似文献   
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