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The Limberg rhombic flap is a reliable and widely used technique in head and neck surgery. Since Limberg introduced his original design in 1946, several modifications of the technique have been described. Although a single Limberg flap is frequently used at the face to close small to medium defects, multi-Limberg flap techniques can help the surgeon to cover moderate to large defects of the extremities, trunk, and back. In this study, a design of four neighboring local Limberg flaps to cover a moderate to large defect without using a skin graft is introduced. It is believed that this design is the geometric limit of multiple Limberg flaps that can entirely cover a single large rhombic defect, because one Limberg flap unit can only be adjoined by three others, one from the tip and two from the sides. This flap design of four local Limberg flaps is also the only geometrically possible design that can keep all the bases of these four flaps free of incisions if one attempts to prepare four small Limberg flaps around a large rhombic defect.  相似文献   
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Objective: Thiol-disulphide homeostasis (TDH) has a critical role in various clinical disorders. We aimed to assess the association of TDH with acute tonsillopharyngitis (AT) in children.

Methods: This study included 94 (73 viral and 21 bacterial) tonsillopharyngitis patients and 88 control children. Their native thiol, total thiol, and disulphide levels were measured.

Results: Viral and bacterial tonsillopharyngitis patients had lower native thiol levels compared with healthy children (P?P?=?0.008, respectively). Both groups had lower total thiol levels compared with control children (P?=?0.002 for viral, P?=?0.011 for bacterial). The disulphide levels were lower in bacterial than in viral tonsillopharyngitis patients (P?=?0.04), and there was a significant difference between viral tonsillopharyngitis patients and the control group (P?P?P?=?0.017 for bacterial). The disulphide/native thiol and disulphide/total thiol ratios were significantly higher in viral (P?P?=?0.017 for both) than in healthy children. In all patients, a correlation was found between the levels of C-reactive protein (CRP) and native thiol (r?=??0.211, P?=?0.04), CRP and total thiol (r?=??0.217, P?=?0.036), white blood cell (WBC) and native thiol (r?=??0.228, P?=?0.002), WBC and total thiol (r?=??0.191, P?=?0.01), and WBC and disulphide (r?=?0.160, P?=?0.03).

Discussion: TDH is altered in AT in children. The alteration is more prominent in viral than in bacterial tonsillopharyngitis.  相似文献   
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BackgroundPrimary Sjögren''s syndrome (pSS) is a disease associated with the overexpression of proinflammatory cytokines, and oxidative stress is one of the factors responsible for its etiopathogenesis. This study aimed to investigate the thiol/disulphide homeostasis in pSS patients.MethodsThe study included 68 pSS patients and 69 healthy controls. Thiol/disulphide homeostasis (total thiol, native thiol, and disulphide levels) was measured using the automatic spectrophotometric method developed by Erel and Neselioglu, and the results of the 2 groups were compared.ResultsThe gender and age distributions of the pSS and control groups were similar (P = 0.988 and P = 0.065). Total thiol and native thiol levels were lower in the pSS group than in the control group (470.08 ± 33.65 µmol/L vs. 528.21 ± 44.99 µmol/L, P < 0.001, and 439.14 ± 30.67 µmol/L vs. 497.56 ± 46.70 µmol/L, P < 0.001, respectively). There were no differences in disulphide levels between groups [17.00 (range 0.70-217.0) µmol/L vs. 14.95 (range 2.10-40.10) µmol/L, P = 0.195].ConclusionsIt was concluded that the thiol/disulphide balance shifted towards disulphide in patients with pSS.  相似文献   
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BackgroundThis study planned to investigate the relationship of dynamic thiol/disulfide homeostasis with the prognosis of myelodysplastic syndrome (MDS).Methods80 patients who had been diagnosed with MDS between 2012 and 2017 and who were older than 18 were included in the study together with 80 healthy control subjects. The MDS diagnosis was confirmed using bone marrow aspiration-biopsy immunostaining. Dynamic thiol/disulfide homeostasis and ischemia-modified albumin (IMA) levels were examined.ResultsThe average IMA (0.71±0.08 vs. 0.67±0.09; p=0.002), median disulfide (18.0 vs. 11.6; p<0.001), median disulfide/native thiol (6 vs. 3; p<0.001), and median disulfide/total thiol (5.4 vs. 2.9; p<0.001) were found higher in the MDS patients compared to control group, and the median hemoglobin, median white blood cell count, median neutrophil count, median lymphocyte count, average native thiol (290.7±48.5 vs. 371.5±103.8; p<0.001), average total thiol (328.2±48.9 vs. 393±105.5; p<0.001), and average native thiol/total thiol (%) (88.3±4.3 vs. 94.2±2.1; p<0.001) were found to below. Risk factors such as collagen tissue disease (HR:9.17; p=0.005), MDS-EB-1 (HR:10.14; p=0.032), MDS-EB-2 (HR:18.2; p=0.043), and disulfide/native thiol (HR:1.17; p=0.023) were found as the independent predictors anticipating progression to acute myeloid leukemia. In the Cox regression model, risk factors such as age (HR:1.05; p=0.002), MDS-EB-1 (HR:12.58; p<0.001), MDS-EB-2 (HR:5.75; p=0.033), disulfide/native thiol (HR:1.14; p=0.040), and hemoglobin (HR:0.64; p=0.007) were found as predictors anticipating for mortality.ConclusionsWe can argue that dynamic thiol/disulfide homeostasis could have significant effects on both the etiopathogenesis and the survival of patients with MDS, and it could be included in new prognostic scoring systems.  相似文献   
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Contamination of soils by heavy metals due to urbanization increases various environmental concerns. The objective of this research was to determine the potential sources of heavy metals in agricultural soils in the vicinity of a small-scale industrial area and to assess their environmental impacts. Soil samples were obtained from 15 different locations near a small industrial area in the Çanakkale province of Turkey. Heavy metal (Cd, Co, Cu, Ni, Pb, Zn) contents of soil samples were determined with four different geochemical fractions via a sequential extraction procedure. The results revealed that pseudo-total heavy metal concentrations were ordered in decreasing order as Zn > Pb > Cu > Ni > Co > Cd. Considering the results, Cd (1.95 ± 0.12 µg/g), Pb (39.21 ± 2.14 µg/g) and Zn (64.99 ± 8.16 µg/g) values were above the normal values specified for agricultural lands. The findings obtained from sequential extraction procedure showed that Cd (78%) and Pb (65%) existed mostly in mobile phases. Such mobile phases originated mostly from anthropogenic sources. These findings were also supported by chemometric analyses. Risk assessments pointed out that while Pb and Zn have moderate risks on the environment, Cd creates high risks.  相似文献   
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Cerebrovascular changes resulting from hydrocephalus still remain to be investigated. It has been suggested that hydrocephalus distorts the large feeding arteries and that the collapse of capillaries results in decreased cerebral blood flow. This clinical study was designed to evaluate the effect of shunting on regional cerebral blood flow in patients with obstructive hydrocephalus of varying duration. Technetium-99m hexamethyl propyleamine oxime (99mTc-HMPAO) was used to measure the cerebral perfusion, semiquantitatively, since the pattern of its distribution in brain is somewhat similar to that of regional cerebral blood flow (rCBF), and the pre and postoperative semiquantitative rCBF values of each lobe were calculated. Fifteen patients (8 F, 7 M) underwent both CT and single photon emission tomography (SPECT) using 99mTc-HMPAO examination before and 1 week after shunting. Mean percentage of all lobes were calculated by subtracting the preoperative mean rCBF of all lobes from the corresponding postoperative values. The patients were classified into 3 groups according to the mean percentage of all lobes. Group A: showed a marked increase in mean cortical blood flow (+ 16.00 +/- 2.9%), group B: a moderate increase (11.27 +/- 4.8%), and in group C: there was the least improvement in mean cortical blood flow (+ 1.17 +/- 2.7%). The mean duration of hydrocephalus of group A, group B and group C was 5 +/- 0.5 weeks, 8 +/- 1 weeks and more than 12 weeks, respectively. Psychological testing and clinical observation of the daily activities of the patients postoperatively showed some correlation with increased rCBF and clinical improvement.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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