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Lasers in Medical Science - Using optical coherence tomography angiography (OCTA), we sought to evaluate parafoveal vascular density (VD) in patients with central serous chorioretinopathy (CSCR)....  相似文献   
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N,N-Substituted benzimidazole salts were successfully synthesized and characterized by 1H-NMR, 13C {1H} NMR and IR techniques, which support the proposed structures. Catalysts generated in situ were efficiently used for the carbonylative cross-coupling reaction of 2 bromopyridine with various boronic acids. The reaction was carried out in THF at 110 °C in the presence of K2CO3 under inert conditions and yields unsymmetrical arylpyridine ketones. All N,N-substituted benzimidazole salts 2a–i and 4a–i studied in this work were screened for their cytotoxic activities against human cancer cell lines such us MDA-MB-231, MCF-7 and T47D. The N,N-substituted benzimidazoles 2e and 2f exhibited the most cytotoxic effect with promising cytotoxic activity with IC50 values of 4.45 μg mL−1 against MDA-MB-231 and 4.85 μg mL−1 against MCF7 respectively.

The in situ prepared four component system Pd(OAc)2, 1,3-dialkylbenzimidazolium halides 2a–i and 4a–i, K2CO3 under CO atmosphere catalyses carbonylative cross-coupling reaction of 2-bromopyridine with various boronic acids to yield unsymmetrical arylpyridine ketones.  相似文献   
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The study was conducted to determine the validity and reliability of the tool used to assess nurses’ attitudes towards futility, and to explore intensive-care nurses’ attitudes towards futility. Principal components analysis revealed that 18item scale was made up of four subdimensions that assess Identifying(beliefs), Decision-Making, Ethical Principles and Law, and Dilemma and Responsibilities related to futile treatments. The internal consistency of the scale was in the acceptable range, with a total Cronbach’s alpha value of 0.72. Overall the results of study suggest that scale can be used as a valid and reliable assessment tool to assess nurses’ attitudes towards futility.  相似文献   
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Vascular reflex mechanisms contribute to vasovagal syncope. However, the alterations in central haemodynamics in patients with vasovagal syncope are unknown. 30 consecutive patients (36.5 ± 15 years, 14 females) with recurrent vasovagal syncope (VVS) and a positive tilt table test were compared to 39 age- and sex-matched controls (36.9 ± 16 years, 15 females) with a negative tilt table result and no history of syncope. Central aortic pressure parameters including augmentation index and central pulse pressure as markers of aortic stiffness were generated non-invasively by applanation tonometry of the radial artery and use of a validated mathematical transfer function. No difference in aortic augmentation index was observed between groups. (VVS 9 ± 2.6 vs. Control 11 ± 2.4, p = 0.8). However, in patients with vasovagal syncope the aortic pressure waveform significantly differed from healthy controls. A prolonged time to the peak of aortic pressure wave (aortic T2) was observed in patients with vasovagal syncope (226 ± 24 vs. 208 ± 21 ms, p = 0.001). Furthermore time to the first shoulder of the aortic pressure wave (aortic T1) was slightly shorter compared to healthy controls, but did not reach statistical significance (106 ± 22 vs. 110 ± 12 ms, p = 0.33). Patients with vasovagal syncope have an altered aortic pressure waveform at rest, but no signs of elevated aortic stiffness. The underlying mechanisms for these findings may potentially result from a complex imbalance of the autonomic nervous system with a continuous deregulation of the sympathetic and parasympathetic reflex arcs.  相似文献   
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Thoracostomy tube placement (TT) is currently one of the most important treatment modalities used in traumatic pneumothorax patients. In patients with low pneumothorax ratio (percentage), both follow-up without surgery and employing intervention when indicated may be appropriate choice. We presented the outcome of patients with low traumatic pneumothorax ratio treated by follow up without surgical intervention in our clinic. During the period from January 2000 until January 2002, 108 patients who were treated and followed with low percentage traumatic pneumothorax in Ankara Numune Hospital Thoracic Surgery Clinic were allocated into three groups due to blunt trauma of the thorax, penetrating-cutting instrument injury and gunshot injury. All patients were admitted to the clinic with the purpose of observation without surgical intervention and chest roentgenograms were taken at the sixth and twelfth hours and daily thereafter. TT was performed for 46 (43%) patients whose pneumothorax ratio increased during the observation period. TT was more frequent in patients with 20% percentage pneumothorax (69%) as well as with two or more fractured ribs (69%). Follow-up without surgical intervention may one of the appropriate modes of treatment in patients who have minimal traumatic pneumothorax.  相似文献   
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