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411.
The electrochemical reduction mechanism of 1-[N-(2-pyridyl)aminomethylidene]-2(1H)-naphthalenone (PN) was investigated by using various electrochemical techniques in 0.1 M tetrabutylammonium tetrafluoroborate (TBATFB) in acetonitrile at glassy carbon (GC) electrode. The number of electrons transferred and diffusion coefficient of the compound were estimated by using an ultramicroelectrode (UME). PN has two reduction peaks in a cyclic voltammogram. Each of them corresponds to a one-electron transfer. In this medium and at the GC electrode surface, the first peak was observed at about ?1.8 V (vs. Ag/Ag+) which is more stable and well defined compared to the second peak. It was determined by using cyclic voltammetry that PN is electroreduced by an EC mechanism. It was also explained by multicycle CV experiments and a dopamine test as well as by Raman spectroscopy that the homogenous chemical reaction is dimerization. The EC mechanism was also examined and the kinetics of this process were calculated by digital simulation.  相似文献   
412.
Poly‐3‐hexylthiophene (P3HT) nanofibers are 1D crystalline structures with semiconductor properties. When P3HT nanofibers are dispersed in nonconducting solvent, they react to external alternate electric field by aligning along the field lines. This can be used to create layers of ordered nanofibers and is referred to as alternating current poling method. P3HT nanofibers with three different size distributions are fabricated, using self‐assembly mechanism in marginal solvents, and used for the alignment studies. Anisotropic absorption of oriented 2 μm long nanofibers exponentially increases with the magnitude of applied field to a certain asymptotic limit at 0.8 V μm?1, while 100–500 nm long nanofibers respond to electric field negligibly. Effective optical birefringence of oriented 2 μm long nanofibers is calculated, based on the phase shift at 633 nm and the average layer thickness, to be 0.41. These results combined with further studies on real‐time control over orientation of P3HT nanofibers in liquid solution or host system are promising in terms of exploiting them in electroabsorptive and electrorefractive applications.

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413.
A 25-year-old woman was referred to our clinic for atypical cyclic pain and masses at both ends of a Pfannenstiel incision scar. Ultrasound of the anterior abdominal wall showed two masses. Both masses were hypoechoic, heterogeneous lesions located at opposite ends of the scar. The lesions were surgically excised with. Microscopic examination revealed endometrial gland structures with endometrial stroma in fibroadipose tissue in sections of both specimens indicative of endometriosis. Incisional endometriosis (IE) is a form of extrapelvic endometriosis especially in scars of obstetric or gynecologic surgery IE may be multifocal at surgical scars. We report the a case of bifocal incisional endometriosis in Pfannesteil scar. Whole scar evaluation should be done for incisional endometriosis and surgical excision should be performed for treatment.  相似文献   
414.
Background/aim The presence of comorbidities in patients with acromegaly causes an increase in morbidity and/or mortality and a decrease in quality of life. In this study, we aimed to investigate the demographic, clinical and laboratory features, prevalence of acromegaly-related comorbidities, and factors associated with these comorbidities in patients with acromegaly.Materials and methods In the study, 96 patients who were followed up with the diagnosis of acromegaly were included. Clinical, laboratory and imaging features, and accompanying comorbidities of the patients were recorded from the patient files.Results Of the patients included in the study, 63 (65.6%) were female and 33 (34.4%) were male. The mean age of diagnosis was 42.61± 12.08, and the mean follow-up period was 9.97 ± 7.26 years. Median insulin-like growth factor 1 level was 238.16 ng/mL (30.5–820), median growth hormone level was 2.05 ug/L (0.1–29.4). A total of 60 (62.5%) of the patients were in the well-controlled group, and 36 (37.5%) had active disease at the time of inclusion. Diabetes mellitus (DM) was detected in 30 (31.3%) patients, prediabetes in 19 (28.8%) patients, hypertriglyceridemia in 38 (42.2%) patients, hypertension (HT) in 41 (42.7%) patients, cardiovascular disease in 5 (5.2%) patients, malignancy in 9 (9.4%) patients, obstructive sleep apnea syndrome in 8 (8.3%) patients, carpal tunnel syndrome in 11 (11.5%) patients, arthropathy in 5 (5.2%) patients, hearing loss in 7 (7.3%) patients, thyroid nodule in 56 (67.5%) patients, thyroid cancer in 4 (4.2%) patients, colonic polyp in 19 (38.8%) patients.Conclusion In this study, we revealed that the most common comorbidities in acromegaly patients in the Turkish population are thyroid nodules, low high-density lipoprotein (HDL cholesterol (HDL-C) level, hypertriglyceridemia, HT, colonic polyps, DM, and prediabetes, and female sex and age at diagnosis are the most important factors associated with comorbidities.  相似文献   
415.

Purpose

In this study, we investigated the effect of lapatinib plus capecitabine treatment in HER2-positive breast cancer patients with brain metastasis.

Methods

Of 405 metastatic breast cancer patients with brain metastases at referral centers in Turkey, 46 were treated with lapatinib plus capecitabine only after the development of brain metastasis. Patients who only received trastuzumab-based therapy after the development of brain metastases were accepted as the historic control group for survival analyses (n = 65). Patients who received both drugs consecutively or sequentially were excluded from the analyses (n = 34).

Results

Median age among 46 patients who received lapatinib plus capecitabine therapy was 45 years (27–76), and median time for development of brain metastases was 11.9 months (0–69 months). Twenty-six out of 38 patients who received lapatinib plus capecitabine and had extracranial metastasis showed partial response or stable diseases (68.4 %). Grade 3-4 toxicity was observed in eight patients (17.3 %). Median overall survival (OS) in patients treated with lapatinib plus capecitabine was significantly increased compared to that in patients treated with trastuzumab-based therapy (19.1 vs. 12 months, respectively, p = 0.039). The incidence of cerebral death was slightly decreased in patients who received lapatinib plus capecitabine compared to those who received trastuzumab-based therapy (32 vs. 43.4 %, p = 0.332). In the multivariate analysis, lapatinib plus capecitabine therapy remained an independent positive predictor for survival [odds ratio (OR), 0.57; p = 0.02].

Discussion

Although this retrospective multicenter study had several limitations, the results suggest that undergoing lapatinib plus capecitabine therapy after the diagnosis of brain metastasis may further improve survival compared to undergoing only trastuzumab-based therapy.  相似文献   
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418.
Cuprizone inhibits mitochondrial function and induces demyelination in the corpus callosum, which resembles pattern III lesions in multiple sclerosis patients. However, the molecular and cellular mechanism by which cuprizone induces demyelination remains unclear. Interleukin-17 (IL-17) secreted by T helper 17 cells and γδT cells are essential in the development of experimental autoimmune encephalomyelitis. In this study, we examined the importance of IL-17 signaling in cuprizone-induced demyelination. We found that mice deficient in IL-17A, IL-17 receptor C (IL-17RC), and adaptor protein Act1 (of IL-17R) all had reduced demyelination accompanied by lessened microglial and polydendrocyte cellular reactivity compared with that in wild-type mice in response to cuprizone feeding, demonstrating the essential role of IL-17-induced Act1-mediated signaling in cuprizone-induced demyelination. Importantly, specific deletion of Act1 in astrocytes reduced the severity of tissue injury in this model, indicating the critical role of CNS resident cells in the pathogenesis of cuprizone-induced demyelination. In cuprizone-fed mice, IL-17 was produced by CNS CD3(+) T cells, suggesting a source of IL-17 in CNS upon cuprizone treatment.  相似文献   
419.
BackgroundSince aortic valve sclerosis (AVS) and coronary artery disease (CAD) share similar cardiovascular risk factors, we hypothesized that the clinical profile of patients with acute myocardial infarction (AMI) would be worse in the presence of AVS. The aim of this study was to investigate the association between AVS and clinical factors in patients with AMI.MethodsThree hundred and fifteen patients with AMI were consecutively enrolled in the study. Echocardiography was used to assess the aortic valve morphology and left ventricular function. The extent and severity of CAD were assessed by Gensini score and the number of obstructed vessels. The patients were divided into 2 groups according to presence or absence of AVS.ResultsThe overall number of patients with AVS was 132 (41.9%). Patients with AVS were older (69.5 ± 11 vs. 59.5 ± 12 years, P < 0.00001). They also had a higher prevalence of hypertension (61% vs. 45%, P = 0.006), prior CAD (33% vs. 23%, P = 0.041), prior AMI (20% vs. 11%, P = 0.019) and a higher percentage were female (32% vs. 19%, P = 0.007) compared with AMI patients without AVS. There was no significant difference between the 2 groups with respect to the Gensini score (P = 0.372). Prior AMI was associated with AVS on age-adjusted logistic regression analyses. A multivariate analysis showed an independent association between the AVS and prior AMI and age (P < 0.0000001, P = 0.022, respectively).ConclusionsOur results showed that the presence of AVS is associated with AMI recurrence.  相似文献   
420.
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