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61.
62.
Atrial fibrillation (AF), which is the most common cardiac arrhythmia, may cause serious symptoms and impair quality of life.1 The development of AF is associated with many risk factors, including age, male gender, hypertension, heart failure, valvular disease, diabetes mellitus (DM) and left atrial (LA) enlargement.2-4 Electrical and/or mechanical remodelling of the atria is thought to be a pathophysiological characteristic of AF.5The pregnant state may be pro-dysrhythmic. This is related to the cardiovascular, hormonal, haemodynamic and autonomic changes during healthy pregnancy. Levels of oestrogen and β-human chorionic gonadotropin increase dramatically. Haemodynamic changes include an increase in circulating blood volume, which increases cardiac output. This results in myocardial stretch and an increase in cardiac end-diastolic volume. High plasma catecholamine concentrations and adrenergic receptor sensitivity increase sympathetic tone. All these changes in pregnant women may make them more prone to dysrhythmogenesis.6Most pregnant women complain of palpitations, dizziness and even syncope, but these symptoms are rarely associated with cardiac dysrhythmias. AF is the most common clinically significant cardiac arrhythmia in the general population but it is rarely seen in pregnant women. When it occurs, it can represent a benign, self-limited lone episode of AF or may be secondary to congenital or rheumatic valvular disease, hypertrophic cardiomyopathy, thyroid disease, or pre-excitation syndrome.Two simple electrocardiogram (ECG) markers, namely maximum P-wave duration (Pmax) and P-wave dispersion (PD), have been used to evaluate intra- and inter-atrial conduction times and the inhomogeneous propagation of sinus impulses, which are well-known electrophysiological characteristics of the atrium prone to fibrillation.7,8 Prolonged Pmax and PD have been reported to represent an increased risk for AF in patients with no underlying heart disease.7,8 Besides, evidence from laboratory and epidemiological research suggests that systemic inflammation may play a role in AF aetiology.9 It has also been demonstrated that atrial electromechanical coupling, measured by tissue Doppler imaging (TDI), as significantly longer in patients with paroxysmal AF than in control groups.10,11To our knowledge, no study evaluating PD and atrial electromechanical coupling has been investigated in pregnant subjects without additional systemic disease. Therefore, in this study we aimed to examine atrial electromechanical coupling and PD, reflecting inter-atrial conduction times in pregnant subjects.  相似文献   
63.
Tuberculous pleuritis can rarely cause haemorrhagic pleural effusion. Dabigatran etexilate can have an additive effect on increasing the risk of haemorrhage. Aspirin cannot cause major haemorrhage, but in the elderly it can cause gastrointestinal bleeding via ulceration of the gastrointestinal mucosa. We report here the case of a 77-year-old male who presented to the hospital with a 2-month history of progressive dyspnoea. He had been taking dabigatran etexilate (220 mg) and high-dose acetylsalicylic acid (aspirin; 300 mg) daily for chronic atrial fibrillation. A chest X-ray revealed a moderately sized right pleural effusion confirmed by a computed tomography scan, which also showed bronchiectasis of both lungs. Dabigatran was discontinued and aspirin was decreased to the minimal therapeutic dose of 100 mg before thoracentesis was performed. Lymphocyte-predominant (50%) haemorrhagic fluid of 500 ml was drained, positive for acid-fast bacilli smear and polymerase chain reaction of Mycobacterium tuberculosis. A chest tube was placed and an additional 1250 ml of haemorrhagic exudate drained out. We treated the patient with a routine regimen of antituberculous medication and the infection resolved without complications other than the bronchiectasis present before treatment. We think that the combination of dabigatran etexilate and high doses of aspirin increased the risk of pleural haemorrhage in this patient with tuberculous pleuritis.  相似文献   
64.
Primary malignant melanoma of the nose and paranasal sinus mucosa is a rare disease and seen in less than 1% among all melanomas. Malignant melanomas have 2 origins: cutaneous and mucosal. The mucosal form has a worse prognosis because of its aggressiveness compared with that of the cutaneous form. Mucosal melanomas often occur at a rate of 2% to 3% among all melanomas and are typically found in the nasal cavity and paranasal sinuses. Generally, it is more common in males and in those older than 50 years. In this study, 4 patients were observed at the Cumhuriyet University Faculty of Medicine; 2 of them were a 64-year-old man and an 82-year-old woman who had a malignant melanoma originating from the nasal septal mucosa, 1 patient was a 72-year-old woman whose malignant melanoma originated from the inferior turbinate, and 1 patient was a 77-year-old woman with a sinonasally located melanoma. The conditions of these patients were discussed under the light of literature instructions.  相似文献   
65.
The hypothalamic Arg-Phe-amide-related peptides, gonadotropin-inhibitory hormone and orthologous mammalian peptides of Arg-Phe-amide, may be important regulators of the hypothalamus-pituitary-gonadal reproductive axis. These peptides may modulate the effects of kisspeptins because they are presently recognized as the most potent activators of the hypothalamus-pituitary-gonadal axis. However, their effects on gonadotropin-releasing hormone neurons have not been investigated. In the current study, the GT1-7 cell line-expressing gonadotropin-releasing hormone was used as a model to explore the effects of Arg-Phe- amide-related peptides on kisspeptin activation. Intracellular calcium concentration was quantified using the calcium-sensitive dye, fura-2 acetoxymethyl ester. Gonadotropin-releasing hormone released into the medium was detected via enzyme-linked immunosorbent assay. Results showed that 100 nmol/L kisspeptin-10 significantly increased gonadotropin-releasing hormone levels (at 120 minutes of exposure) and intracellular calcium concentrations. Co-treatment of kisspeptin with 1 μmol/L gonadotropin-inhibitory hormone or 1 μmol/L Arg-Phe-amide-related peptide-1 significantly attenuated levels of kisspeptin-induced gonadotropin-releasing hormone but did not affect kisspeptin-induced elevations of intracellular calcium concentration. Overall, the results suggest that gonadotropin-inhibitory hormone and Arg-Phe-amide-related peptide-1 may have inhibitory effects on kisspeptin-activated gonadotropin-releasing hormone neurons independent of the calcium signaling pathway.  相似文献   
66.
This study evaluated the root canal seal achieved by irradiation with an erbium, chromium:yttrium‐scandium‐gallium‐garnet laser, and the optimal output power to remove debris and the smear layer were determined. One hundred mandibular premolar teeth were prepared and divided into four groups. Group 1 was not lased but was irrigated with 5 mL of 5.25% NaOCl and 5 mL of 17% ethylenediaminetetraacetic acid. Group 2 was irradiated at a panel setting of 1 W, group 3 at 2 W and group 4 at 2.5 W, with a 50% water level and 48% air‐cooling level. Root canals were obturated by cold lateral compaction, and apical microleakage was measured using a fluid filtration model. The remaining debris and smear layer were evaluated via scanning electron microscopy. Statistically significant differences were detected between groups. Irradiation at 1 and 2 W using an erbium, chromium:yttrium‐scandium‐gallium‐garnet laser produced a seal superior to that of the other treatments.  相似文献   
67.
68.
Although inflammation is a physiologic response designed to protect us from infection, when unchecked and ongoing it may cause substantial harm. Both chronic heart failure (CHF) and chronic kidney disease (CKD) are known to cause elaboration of several pro-inflammatory mediators that can be detected at high concentrations in the tissues and blood stream. The biologic sources driving this chronic inflammatory state in CHF and CKD are not fully established. Traditional sources of inflammation include the heart and the kidneys which produce a wide range of pro-inflammatory cytokines in response to neurohormones and sympathetic activation. However, growing evidence suggests that non-traditional biomechanical mechanisms such as venous and tissue congestion due to volume overload are also important as they stimulate endotoxin absorption from the bowel and peripheral synthesis and release of pro-inflammatory mediators. Both during the chronic phase and, more rapidly, during acute exacerbations of CHF and CKD, inflammation and congestion appear to amplify each other resulting in a downward spiral of worsening cardiac, vascular, and renal functions that may negatively impact patients’ outcome. Anti-inflammatory treatment strategies aimed at attenuating end organ damage and improving clinical prognosis in the cardiorenal syndrome have been disappointing to date. A new therapeutic paradigm may be needed, which involves different anti-inflammatory strategies for individual etiologies and stages of CHF and CKD. It may also include specific (short-term) anti-inflammatory treatments that counteract inflammation during the unsettled phases of clinical decompensation. Finally, it will require greater focus on volume overload as an increasingly significant source of systemic inflammation in the cardiorenal syndrome.  相似文献   
69.
An 18-year-old female came to our clinic with complaints of a tender lump just under her jaw on the left side and another lump in front of her left ear, ecchymosis around the eye and some redness in the eye at the same side. After administering antibiotic therapy for two days we suspected of tularemia and referred the patient to the Infectious Diseases Department. A serum sample was taken and a fine needle aspiration biopsy was performed. The patient was diagnosed with tularemia, the oculoglandular syndrome of Parinaud. Tularemia should also be kept in mind for differential diagnosis in patients with both ocular and glandular symptoms in endemic regions like Turkey and the appropriate therapy should be initiated immediately.  相似文献   
70.
ObjectiveTo assess the choroidal structural characteristics in the first and third trimesters in pregnant women using enhanced depth imaging optical coherence tomography and binarization method.DesignProspective study.ParticipantsTwenty-five eyes of 25 pregnant women in the first trimester (group 1) and 25 eyes of 25 pregnant women in the third trimester (group 2) were examined. Healthy age-matched 25 participants were enrolled as a control group (group 3).MethodsThe choroidal thickness (CT) was measured at 3 points; subfoveal, 1500 μm nasal to the fovea, and 1500 μm temporal to the fovea. Total choroidal area, luminal area, stromal area, stroma/lumen ratio, and choroidal vascularity index (CVI) were measured by Image-J software.ResultsThe mean subfoveal and nasal CT were statistically significantly increased in group 1 compared with controls (p = 0.005 and p = 0.004, respectively). The mean temporal CT was statistically significantly increased in group 1 compared with groups 2 and 3 (group 1 vs group 2, p = 0.043; group 1 vs group 3, p = 0.011). The mean total choroidal area, stromal area, and luminal area were significantly increased in groups 1 and 2 compared with control group (p < 0.001, p < 0.001, p < 0.001, and p < 0.001, p = 0.002, p = 0.002, respectively). There were no statistically significant differences among groups in terms of mean stroma/lumen ratio and CVI (p = 0.148 and p = 0.312, respectively).ConclusionsThere was a significant increase in subfoveal, temporal, and nasal CT in the first trimester. Total choroidal, stromal, and luminal areas were significantly increased in the first and third trimesters.  相似文献   
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