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931.
Hypertension is a major contributor to the development of heart failure with preserved ejection fraction (HFpEF). Our understanding of the epidemiology and pathophysiology of HFpEF in relation to hypertension has increased considerably in recent years. We now know that the pathophysiologic relationship between hypertension and HFpEF is more complex than simply the development of left ventricular hypertrophy and diastolic dysfunction and that there are multiple ways in which hypertension interacts with other comorbidities, the vasculature, and the heart to predispose to HFpEF. Although the treatment of HFpEF has been challenging, there is widespread agreement that control of systemic blood pressure is important in the management of these patients. Here we review the relationship between hypertension and HFpEF, focusing on (1) epidemiology and (2) pathophysiology of HFpEF in relation to hypertension; (3) prevention of HFpEF by controlling hypertension; and (4) established and novel therapeutics for hypertension in the setting of HFpEF. 相似文献
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933.
Oktay Algin 《Acta neurologica Belgica》2018,118(2):169-178
The major advantages of three-dimensional sampling perfection with application optimized contrasts using different flip-angle evolution (3D-SPACE) technique are its high resistance to artifacts that occurs as a result of radiofrequency or static field, the ability of providing images with sub-millimeter voxel size which allows obtaining reformatted images in any plane due to isotropic three-dimensional data with lower specific absorption rate values. That is crucial during examination of cerebrospinal-fluid containing complex structures, and the acquisition time, which is approximately 5 min for scanning of entire cranium. Recent data revealed that T2-weighted (T2W) 3D-SPACE with variant flip-angle mode (VFAM) imaging allows fast and accurate evaluation of the hydrocephalus patients during both pre- and post-operative period for monitoring the treatment. For a better assessment of these patients; radiologists and neurosurgeons should be aware of the details and implications regarding to the 3D-SPACE technique, and they should follow the updates in this field. There could be a misconception about the difference between T2W-VFAM and routine heavily T2W 3D-SPACE images. T2W 3D-SPACE with VFAM imaging is only a subtype of 3D-SPACE technique. In this review, we described the details of T2W 3D-SPACE with VFAM imaging and comprehensively reviewed its recent applications. 相似文献
934.
Oktay K. Gasymov Chiara Botta Laura Ragona Aytaj J. Guliyeva Henriette Molinari 《Macromolecular chemistry and physics.》2019,220(4)
Described herein is the preparation of dye‐doped films employing silk fibroin (SF) as a biomaterial, capable of preserving the optical properties of the monomeric dye in the solid state, a critical requisite for optical and biolaser applications. A comprehensive physical–chemical characterization is reported for SF films doped with Rhodamine 6G, an ideal candidate for photonics and optoelectronics. Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD) and X‐Ray diffraction (XRD) provide information on SF secondary conformation in the presence of rhodamine. UV–vis absorption spectra and exciton CD inform on the structure of encapsulated rhodamine, while changes in dye photophysical properties illuminate the molecular mechanism of the involved host–guest interactions. SF host environment inhibits rhodamine dimer formation, indicating that SF is an optimum matrix to keep rhodamine essentially monomeric at concentrations as high as 7 mm in the film. The relevant optical properties of these films and the easiness of their preparation, make these systems optimal candidates for innovative photonic technologies. 相似文献
935.
Gülcü Oktay Aksakal Emrah Aydemir Selim Doğan Remziye Saraç İbrahim Aydın Sidar Şiyar Öztürk Mustafa Aksu Uğur Kalkan Kamuran Tanboğa İbrahim Halil 《Journal of thrombosis and thrombolysis》2022,53(1):88-95
Journal of Thrombosis and Thrombolysis - Although COVID-19 disease primarily affects the respiratory system, it has been seen in many studies that it causes thromboembolic (TE) events in many... 相似文献
936.
937.
Cezmi Dogan Huseyin Yetik Osman Sevki Arslan Hakki Oktay Seymen Oner Suzer Ovgu Aydin 《Cutaneous and ocular toxicology》2019,38(2):201-205
Purpose: To determine the effects of intravitreally injected aspirin on normal ocular tissues.Methods: Six eyes of 3 rabbits as a control group, 18 eyes of 9 albino rabbits which were injected aspirin intravitreally were studied. In the control group, the same volume of balanced salt solution (BSS) as in drug groups were injected. Clinical examination methods including biomicroscopy, indirect ophthalmoscopy, and Schiotz tonometry, electrophysiological test including ERG, and histopathological examination including light microscopy were used to evaluate the ocular effects after drug injections. All the study tests were performed before the injections and 1?week, 1?month, and 3?months after the injections as well.Results: No significant toxicity was determined after injection in terms of the clinical examination methods in all eyes. Cataracts were observed in 27.7% (5/18) of the eyes in the study group. All cataracts in 5 eyes disappeared at the end of three months. In tonometry, no value out of the normal range of rabbits (17.5?±?3.1?mmHg) was observed. No toxicity sign was observed at electrophysiological and histopathological evaluations.Conclusion: After intravitreal injection of aspirin, no significant toxicity sign was observed other than a reversible cataract. Thus, intravitreal aspirin injections may be an additional or alternative treatment option for several anterior or posterior segment ocular diseases in addition to their topical utilization. 相似文献
938.
939.
940.
OBJECTIVE: The mechanisms of the different haemodynamic and clinical responses to dobutamine infusion in mitral stenosis (MS) are not clearly established. The aim of this study was to evaluate the relation between left atrial (LA) function and haemodynamic response in patients with MS during dobutamine infusion. METHODS AND RESULTS: Forty-two consecutive moderately symptomatic patients (33 women, 9 men; mean age 46+/-9, range from 26 to 66), New York Heart Association (NYHA) class II with MS (mean mitral valve area 1.7+/-0.1 cm2) were evaluated with dobutamine stress echocardiography. Haemodynamic measurements were obtained at rest and during peak dobutamine infusion. LA fractional shortening at rest was used as an index of global LA function. Group I consisting of patients with significantly elevated pulmonary artery pressure (> 60 mm Hg) and mean transmitral gradient (> 15 mm Hg) at peak dobutamine infusion were defined as haemodynamically serious MS. Group II consisted of the remaining 30 patients whose haemodynamic data were below these levels. While baseline haemodynamic parameters and mitral valve characteristics were not different between the two groups, LA fractional shortening was significantly lower (18.9+/-2.8 vs. 32.3+/-5.1%, p<0.0001) and left atrial dimension was significantly larger in group I (49.7+/-2.3 mm vs 43.6+/-5.3 mm, p<0.0001). Left atrial fractional shortening was negatively correlated with the increase in mean transmitral gradient (r:-0.58, p<0.01). When the patients were divided using a LA fractional shortening level of 25% as the cut-off point, we observed that the patients with low LA fractional shortening had a greater increase in mean transmitral gradient (7.3+/-3.1 mm Hg vs. 4.6+/-1.4 mm Hg), p = 0.005) and pulmonary artery pressure (22.4+/-3.5 mm Hg vs. 16.1+/-8.5 mm Hg, p = 0.001) compared to the patients with high LA fractional shortening. Based on these haemodynamic results, management was changed in 12 patients (28%): 5 underwent percutaneous mitral balloon commissurotomy and 7 received intensive medical treatment. CONCLUSIONS: The present study demonstrates that haemodynamic response during dobutamine stress echocardiography correlates with LA fractional shortening in patients with MS. The evaluation of left atrial function at rest in patients with ambiguous symptoms and mild mitral stenosis may be useful in clinical decision making. Atrial dysfunction at rest may predict the haemodynamic response during stress echo in these patients. 相似文献