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1.
BACKGROUND: Despite plenty of research, the cause of recurrent aphthous stomatitis (RAS) remains obscure. It has been proposed that, the aetiological factors such as local trauma, smoking, vitamin deficiencies and viral infections lead to aphthae formation via final common pathway based on increased oxidative stress. The aim of this investigation was to evaluate the antioxidant enzyme superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) alterations in plasma and saliva, and in addition uric acid (UA) in saliva, in patients with RAS and healthy controls. METHODS: Thirty-two patients with RAS and 30 healthy controls were included into the study. The SOD, CAT, GSHPx and UA levels were measured in plasma and saliva in study and control groups. RESULTS: In the RAS group, although the mean SOD (P<0.001) and CAT (P<0.05) levels of plasma were lower, GSHPx (P<0.001) levels were higher than control group. The salivary concentrations of the SOD (P<0.001), CAT (P<0.05) and GSHPx (P<0.001) in RAS group were entirely opposite to plasma concentrations. UA were not significant between RAS group and controls. CONCLUSION: Since we found salivary SOD and CAT levels were high whereas plasma levels were low, it has been thought that, salivary defence mechanisms via antioxidant agents may be stimulated against to the ulcerous lesion. We consider that the organism might mobilize the antioxidant potential to the sites where they were needed. At this point, decrease of SOD and CAT levels in the plasma may be related to this shift. It is also thought that GSHPx secretion in the saliva may also be increased but the increase in its turnover may be responsible for the diminished activity.  相似文献   
2.
The lumbrical muscles are located in the midpalm, dorsal to the palmar aponeurosis. The main function of these muscles is an indirect contribution to interphalangeal joint extension by decreasing the flexor effect of the flexor digitorum profundus muscle. Due to their minor biomechanical functions and suitable constructions, these muscles have been preferred in reconstructive surgery as local transposition flaps or pedicled flaps. Despite the surgical and clinical importance, vascular anatomical studies of these muscles are not well represented in the current literature. This study was performed in the Department of Anatomy of the Faculty of Medicine of the Ege University. Thirty-four cadaver hands, injected with red-coloured latex were used, and we aimed to describe the morphometry and vascular anatomy of the lumbrical muscles. We measured the length and width of the muscles, after removing their epimisium, and the diameter and length of the arteries to the muscles. The outcomes of our study determined that the length and width of the lumbrical muscles were reduced significantly from radial towards ulnar sides. The lumbrical muscles were supplied from both their palmar and dorsal surfaces by both superficial and deep palmar arches and/or their branches. We also described the level of entry of the dominant arteries for each lumbrical muscle and measured the size of the vessels and muscles to guide some surgical approaches. This anatomical study could guide for some surgical approaches and reduce the deficiency about the vascular anatomical patterns of the lumbrical muscles in the literature.  相似文献   
3.
Polyester-crystic cast was observed to reach the peritubular capillary plexus following injection in sheep kidneys. Microvascular structures in this region are also reported in this study. Glomeruli were found to vary in size and shape. Diameters of afferent arterioles were larger than those of efferent arterioles. The glomerulus is supplied by more than one afferent arteriole, and in some regions, the blood in afferent arterioles joins collateral circulation via the intercapillary plexus. Morphological properties at the end of the peritubular capillary plexus were found to be remarkably significant.  相似文献   
4.
Here we assessed the effects of i.g. administration of Zingicomb (ZC), a mixture of zingiber officinale and ginkgo biloba extracts, on learning and memory, and on indicators of oxidative stress in aged rats. Effects of ZC (1 and 10 mg/kg) were investigated in 22-24 months old Wistar rats using the Morris water maze, in which they show deficient performance as compared to 3 months old rats in the undrugged state (days 1 and 2). Treatment was administered on days 3 and 4 of training, then over 7 days with training discontinued, and again on days 5 and 6 when training was resumed. Thereafter chronic treatment was maintained over 5 months. 1 mg/kg ZC improved escape learning in the water maze. The two capital indicators of oxidative stress in brain homogenates, the amount of oxidized proteins (assessed as carbonyl group containing proteins) and lipid peroxidation, were significantly reduced in ZC treated animals. Thus, ZC, which had previously been shown to improve inhibitory avoidance learning and to have anxiolytic properties in adult animals, might also facilitate spatial learning in aged animals, and reduces indices of oxidative stress in brain tissue after chronic treatment.  相似文献   
5.
Chondrosarcoma is a rare tumor. In this study, we present a case with laryngeal chondrosarcoma that was treated by an endolaryngeal approach using an operation microscope. The patient remains disease-free to date, with no evidence of new or recurrent disease more than 3 years after the endolaryngeal surgery. The computerized tomography and endoscopic examinations did not reveal any recurrent disease, indicating the success of the endolaryngeal approach.  相似文献   
6.
7.
Aim: In diabetes mellitus (DM) patients, left ventricular dysfunction is widely evaluated and established by conventional diagnostic methods, whereas right ventricular (RV) function is not as sufficiently evaluated. The aim of this study is to assess the preclinical effects of DM on RV function by using novel Tissue Doppler Imaging (TDI)‐derived indices. Methods: The study included 96 patients with type II DM [60 with DM only and 36 patients with coexisting DM and hypertension (DMHT)] and 40 healthy controls. Conventional parameters and TDI‐derived systolic velocities of tricuspid annulus [isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), RV Tei index] were measured. Results: TDI‐derived RV IVA was significantly lower in both DM and DMHT patients compared to controls indicating subclinical impairment in RV systolic function in the study patients (P = 0,0001). However RV IVA was similar in DM and DMHT subgroup supporting RV systolic impairment in DM was independent from HT. In correlation analysis, RV IVA was significantly correlated with the existence of diabetic nephropathy (r =?0,38; P = 0,003), retinopathy (r =?0,35; P = 0,006), insulin resistance (r =?0,52; P = 0,0001). Conclusions: Diabetes is associated with subclinical RV systolic dysfunction, regardless of coexisting hypertension. Tissue Doppler‐derived IVA; is a novel, non‐invasive parameter which may be used in early detection of RV systolic dysfunction in patients with DM. (Echocardiography 2010;27:1211‐1218)  相似文献   
8.
A 75-year-old man, with a previous history of myocardial infarction and three-vessel coronary artery bypass grafting, presented with an acute anterior ST-elevation myocardial infarction. The vein graft to the left anterior descending artery was occluded with heavy thrombus burden, and the other grafts were patent. After administering a bolus dose of tirofiban and then undergoing percutaneous coronary intervention without stenting to the left anterior descending artery saphenous vein graft, intracoronary thrombolytic infusion was performed to maintain the patency of the vein graft. The patient was asymptomatic after medical follow-up. This may be an effective treatment option in patients with large thrombus burden and requires further investigation through large-scale trials.  相似文献   
9.
Lupus vulgaris is the most common form of cutaneous tuberculosis which usually occurs in patients previously sensitized to Mycobacterium tuberculosis. We present a case of a 10-year-old boy who was diagnosed as lupus vulgaris clinically and histopathologically. He had well demarcated, irregularly bordered, pink, infiltrated plaques on his left cheek showing apple-jelly appearance on diascopy. The histopathological examination showed tuberculoid granulomas with Langhans type giant cells. The Mantoux reactivity was in normal limits, and no acid-fast bacilli was found in the lesion, either by direct stained smears or by culture. The lesions showed marked improvement on anti-tuberculosis treatment. We want to emphasize that histopathological examination has diagnostic value in lupus vulgaris in correlation with clinical appearance, when direct analysis or culture is negative.  相似文献   
10.
Different lines of evidence support an association between Epstein-Barr virus (EBV) and gastric cancer (GC). The main understood risk factor to develop GC is infection by Helicobacter pylori (H. pylori), which triggers a local inflammatory response critical for progression from gastritis to GC. The role of EBV in early inflammatory gastric lesions has been poorly studied. A recent study proposed a cutoff value of 2000 EBV particles to identify patients with increased chances of infection of the gastric epithelium, which may favor the inflammatory process. To better understand the role of EBV in cancer progression, we analyzed 75 samples of GC, 147 control samples of non-tumor gastric tissue derived from GC patients and 75 biopsies from patients with non-atrophic gastritis (NAG). A first-round PCR was used for EBV detection in tumor and non-tumor controls and a more sensitive nested PCR for gastritis samples; both PCRs had lower detection limits above the proposed cutoff value. With this strategy 10.67% of GC, 1.3% of non-tumor controls and 8% of gastritis samples were found positive. An EBER1 in situ hybridization showed EBV infection of epithelial cells in GC and in a third of NAG samples, while in the other NAGs infection was restricted to the mononuclear cell infiltrate. EBV-positive GCs were enriched in lace and cribriform patterns, while these rare patterns were not observed in EBV negative samples. Our results support a role for EBV in GC and early precursor lesions, either as directly oncogenic infecting epithelial cells or indirectly as an inflammatory trigger.  相似文献   
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