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51.
Tomasz Jazwiec Marcin Malinowski Haley Ferguson Jeremy Wodarek Nathan Quay Jared Bush Matthew Goehler Jessica Parker Manuel Rausch Tomasz A. Timek 《The Journal of thoracic and cardiovascular surgery》2021,161(4):e277-e286
ObjectiveTo investigate the effect of variable tricuspid annular reduction (TAR) on functional tricuspid regurgitation (FTR) and right ventricular (RV) dynamics in ovine tachycardia-induced cardiomyopathy.MethodsNine adult sheep underwent implantation of a pacemaker with an epicardial lead and were paced at 200 to 240 bpm until the development of biventricular dysfunction and functional TR was noted. During reoperation on cardiopulmonary bypass, 6 sonomicrometry crystals were placed around the tricuspid annulus (TA) and 14 were placed on the RV epicardium. Annuloplasty suture was placed around the TA and externalized to an epicardial tourniquet. After weaning from cardiopulmonary bypass, echocardiographic, hemodynamic, and sonomicrometry data were acquired at baseline and during 5 progressive TARs achieved with suture cinching. TA area and RV free wall strains and function were calculated from crystal coordinates.ResultsAfter pacing, changes in left ventricular (LV) ejection fraction and RV fractional area decreased significantly. Mean TA diameter increased from 25.1 ± 2.9 mm to 31.5 ± 3.3 mm (P = .005), and median TR (range, 0-3+) increased from 0 (0) to 3 (2) (P = .004). Progressive suture cinching reduced the TA area by 18 ± 6%, 38 ± 11%, 56 ± 10%, 67 ± 9%, and 76 ± 8%. Only aggressive annular reductions (67% and 76%) decreased TR significantly, but these were associated with deterioration of RV function and strain. A moderate annular reduction of 56% led to a substantial reduction of TR with little deleterious effect on regional RV function.ConclusionsA moderate TAR of approximately 50% may be most advantageous for correction of functional TR and simultaneous maintenance of regional RV performance. Additional subvalvular interventions may be needed to achieve complete valvular competence. 相似文献
52.
Eleonora Mess Magdalena Witkowicz Maciej Ornat Piotr Sielski Tomasz Klaszczyk 《Archives of Psychiatric Nursing》2018,32(5):688-694
The objective of the study was to assess the severity of depression and to assess the level of self-sufficiency of patients with Alzheimer's disease, with particular emphasis on the place of residence and level of education. The study covered 90 people diagnosed with Alzheimer's disease. All respondents were persons over 65?years of age and residents of cities with a population over one-hundred thousand. The research method based on this work is the author's own questionnaire, the Zung Self-Rating Depression Scale (ZSDS) about depression and the Karnofsky Performance Scale Index (KPSI) for assessment of a patient's self-sufficiency. Regardless of residence, patients with Alzheimer's disease displayed signs of mild or moderate depression (100% in social welfare homes and hospital patients and 60% in those with caregivers at home). Patients with Alzheimer's disease have an unsatisfactory salary in social-economic terms. In those with Alzheimer's disease, quality of life is best for those in family homes under the care of their immediate family. People with a vocational education were the largest group of people diagnosed with Alzheimer's. Patients at home and in the hospital had a higher level of physical activity, but most patients in the hospital needed regular medical care, as did patients in social welfare homes. 相似文献
53.
This paper presents experimental investigations of reinforced concrete (RC) beams flexurally strengthened with carbon fiber reinforced polymer (CFRP) strips. Seven 3300 mm × 250 mm × 150 mm beams of the same design, with the tension reinforcement ratio of 1.01%, were tested. The beams differed in the way they were strengthened: one of the beams was the reference, two beams were passively strengthened as precracked (series B-I), two beams were passively strengthened as unprecracked (series B-II) and two beams were actively strengthened as unprecracked (series B-III). Moreover, the strengthening parameters differed between the particular series. The parameters were: CFRP strip cross-sectional areas (series B-I, B-II) or prestressing forces (series B-III). The beams were statically loaded, up to the assumed force value, in the three-point bending test and deflections at midspan were registered. After unloading the beams were suspended on flexible ropes (the free-free beam system) and their eigenfrequencies were measured using operational modal analysis (OMA). The static measurements (deflections) and the dynamic measurements (eigenfrequencies) were conducted for the adopted loading steps until failure. Static stiffnesses and dynamic stiffnesses were calculated on the basis of respectively the deflections and the eigenfrequencies. The qualitative and quantitative differences between the parameters are described. 相似文献
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Rakowski Tomasz Siudak Zbigniew Dziewierz Artur Plens Krzysztof Kleczyński Paweł Dudek Dariusz 《Journal of thrombosis and thrombolysis》2018,45(1):151-157
Journal of Thrombosis and Thrombolysis - According to guidelines, it is recommended to give P2Y12 inhibitors (preferably ticagrelor or prasugrel) at the time of first medical contact in patients... 相似文献
58.
Validation of a semi‐automatic co‐registration of MRI scans in patients with brain tumors during treatment follow‐up
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Anouk van der Hoorn Jiun‐Lin Yan Timothy J. Larkin Natalie R. Boonzaier Tomasz Matys Stephen J. Price 《NMR in biomedicine》2016,29(7):882-889
There is an expanding research interest in high‐grade gliomas because of their significant population burden and poor survival despite the extensive standard multimodal treatment. One of the obstacles is the lack of individualized monitoring of tumor characteristics and treatment response before, during and after treatment. We have developed a two‐stage semi‐automatic method to co‐register MRI scans at different time points before and after surgical and adjuvant treatment of high‐grade gliomas. This two‐stage co‐registration includes a linear co‐registration of the semi‐automatically derived mask of the preoperative contrast‐enhancing area or postoperative resection cavity, brain contour and ventricles between different time points. The resulting transformation matrix was then applied in a non‐linear manner to co‐register conventional contrast‐enhanced T1‐weighted images. Targeted registration errors were calculated and compared with linear and non‐linear co‐registered images. Targeted registration errors were smaller for the semi‐automatic non‐linear co‐registration compared with both the non‐linear and linear co‐registered images. This was further visualized using a three‐dimensional structural similarity method. The semi‐automatic non‐linear co‐registration allowed for optimal correction of the variable brain shift at different time points as evaluated by the minimal targeted registration error. This proposed method allows for the accurate evaluation of the treatment response, essential for the growing research area of brain tumor imaging and treatment response evaluation in large sets of patients. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
59.
Barbara Jasiewicz Jacek Pietraszek Sławomir Duda Szymon Pietrzak Błażej Pruszczyński Tomasz Parol Tomasz Potaczek Aneta Gądek-Moszczak 《Foot and Ankle Surgery》2021,27(4):371-376
BackgroundFoot bones in children have more rounded shapes in radiograms than adults. Thus, the goal of this work was assessing inter- and intra-observer reliability in paediatric forefoot angle measurements.Material and methodsSix forefoot angles in 34 AP standing paediatric foot radiographs were measured by 5 researchers. A classic statistical analysis with use of IBM SPSS Statistics 25 was performed and a new method with two-way analysis of variance was applied.ResultsResults of statistical analysis revealed the properties of a subjective assessment related to specific angles. Kilmartin’s angle, calcaneus-fifth metatarsal angle and first ray angle are the most reliable; metatarsus adductus angle should be used with great caution in pediatric population. Engel’s angle is the most difficult for measuring and measurement error is the highest.ConclusionThe power of paediatric forefoot measurements is various. Several angles are reliable, while Engle’s angle is the most doubtful. 相似文献