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排序方式: 共有7136条查询结果,搜索用时 15 毫秒
101.
Vriz Olga Palatini Paolo Mos Lucio AlSergani Hani Vendramin Igor Livi Ugolino Antonini-Canterin Francesco Magne Julien 《The international journal of cardiovascular imaging》2021,37(5):1659-1668
The International Journal of Cardiovascular Imaging - Aortic valve stenosis (AS) shares similarities with the atherosclerotic process but little is known about the effect of the mechanical... 相似文献
102.
Pablo M Munarriz Eduardo Brcena Jose F Aln Ana M Castao-Leon Igor Paredes Luis Miguel Moreno-Gmez Daniel García-Prez Luis Jimnez-Roldn Pedro A Gmez Alfonso Lagares 《Interventional neuroradiology》2021,27(2):191
ObjectiveTo analyze the reliability and accuracy of morphological measurements of software employed to three-dimensionally reconstruct aneurysms and vessels (VMTKlab, version 1.6.1,) with computed tomography angiography (CTA) as the source of images. Agreement with measurements from three-dimensional digital subtraction angiography (3 D-DSA) was evaluated.MethodsWe evaluated 40 patients presenting with aneurysmal subarachnoid hemorrhage (aSAH). We analyzed four main variables of the aneurysm morphology: absolute height (size), neck (maximum neck width), perpendicular height, and maximum width. The CTA images were uploaded to the software and then segmented to reconstruct the aneurysm. This new method was compared to the current gold standard—3D reconstruction of pretreatment cerebral angiography. We used intraclass correlation coefficient (ICC) and Bland-Altman plot analyses to evaluate the agreement between these methods.ResultsThe ICCs obtained for absolute height, neck, perpendicular height, and maximum width were 0.85, 0.57, 0.85, and 0.89, respectively. This implied good agreement except for the neck of the aneurysm (moderate agreement). Bland-Altman plots are presented for the four indexes. The average of the differences was not significant in terms of absolute height, perpendicular height, and maximum width indicating good agreement. However, it was significant for the neck of the aneurysm.ConclusionsWe report good agreement between the values generated using VMTKlab and cerebral angiography for three of the four main variables. Discrepancies in neck diameter are not surprising and its underestimation with a traditional delineation from cerebral angiography has been reported before. 相似文献
103.
Igor R C Bienert Rogério Carvalho de Oliveira Pedro Beraldo de Andrade Carlos Antonio Caramori 《Brazilian Journal Of Cardiovascular Surgery》2015,30(2):254-259
Bibliometry is a quantitative statistical technique to measure levels of
production and dissemination of knowledge, as well as a useful tool to track the
development of an scientific area. The valuation of production required for
recognition of researchers and magazines is accomplished through tools called
bibliometricindexes, divided into quality indicators and scientific impact.
Initially developed for monographs of statistical measures especially in
libraries, today bibliometrics is mainly used to evaluate productivity of
authors and citation repercussion. However, these tools have limitations and
sometimes provoke controversies about indiscriminate application, leading to the
development of newer indexes. It is important to know the most common search
indexes and use it properly even acknowledging its limitations as it has a
direct impact in their daily practice, reputation and funds achievement. 相似文献
104.
Treatment of pleural malignancies by photo‐induction combined to systemic chemotherapy: Proof of concept on rodent lung tumors and feasibility study on porcine chest cavities 下载免费PDF全文
105.
106.
Comparative impact of continent and incontinent urinary diversion on long‐term renal function after radical cystectomy in patients with preoperative chronic kidney disease 2 and chronic kidney disease 3a 下载免费PDF全文
107.
DIFFERENCES IN FREE AMINO ACID CONTENT OF SEEDLINGS OF AWNED AND HOODED BARLEY, AND THEIR ALTERATION BY CHLORAMPHENICOL TREATMENT 总被引:1,自引:0,他引:1 下载免费PDF全文
108.
Robert J. Reed Igor Grant Sean B. Rourke 《Alcoholism, clinical and experimental research》1992,16(4):677-683
It is generally believed that many non-Korsakoff alcoholics have subtle defects in memory. To determine whether such defects vary as a function of length of abstinence (LOA), we performed extensive memory testing with: (1) recently detoxified (n = 31; LOA-29 days); (2) intermediate-term abstinent (n = 28; LOA = 1.9 years); (3) long-term abstinent (n = 32; LOA-7.0 years) alcoholics; and (4) nonalcoholic controls (n = 37). All subjects were matched on age and education. Alcoholics were matched on years of alcoholic drinking. Memory measures were divided into the following domains: verbal learning, verbal recall, visual learning, visual recall, and paired associate learning. A series of MANOVAs were conducted that revealed a significant relationship between visual learning and length of abstinence, and a significant interaction between age and length of abstinence on visual recall. Long-term abstinent subjects were not significantly different from controls on any test. We conclude that memory disturbance demonstrable among recently detoxified alcoholics in the early weeks of their abstinence is not evident in demographically matched long-term abstinent alcoholics with similar drinking histories. 相似文献
109.
Maeng-Hee Kang Igor Spigelman Richard W. Olsen 《Alcoholism, clinical and experimental research》1998,22(9):2165-2173
Chronic intermittentethanol (CIE)-treated rats exhibited a kindlinglike persistent increase in withdrawal hyperexcitability. The alteration of GABAA receptor (QABAAR) function in the hippocampus was suggested as a possible mechanism underlying the hyperexcitability observed in CIE rats, because (1) GABAAR agonist (muscimol)-evoked 38Cl- efflux was decreased; (2) paired-pulse inhibition in the CA1 area, predominantly due to GABAAR-mediated recurrent inhibition, was persistently decreased; and (3) GABAAR subunit expression was altered in the hippocampus from CIE rats. To further characterize the functional alteration of GABAAR after CIE treatment, their sensitivity to acute ethanol, a steroid anesthetic (alphaxalone), and a benzodiazepine inverse agonist (DMCM; methyl-6, 7-dimethoxy-4-ethyl-β-carboline-3-carboxylate) were studied using either synaptically evoked GABAAR responses or exogenously applied muscimol-evoked responses in hippocampal slices. Bath application of ethanol (60 mM) enhanced the area of GABAAR-mediated inhibitory postsynaptic potentials in the hippocampal CA1 region from control and CIE rats, and this potentiation was significantly (p = 0.027) greater in CIE rats (98%) than in control rats (53%). The positive modulatory effect of alphaxalone (1 μM) on GABAAR-inhibitory postsynaptic potentials was not significantly different between control and CIE rats (p = 0.375), whereas alphaxalone allosterically increased [3H]flunitrazepam binding in the CA1 area only in CIE rats (by 20 to 25%, p < 0.01), but not in controls. On the other hand, the negative modulatory effect of DMCM (1 μM) on muscimol-evoked responses was significantly larger in CIE rats (p = 0.002). These results suggest that the sensitization of GABAAR to acute ethanol and benzodiazepine inverse agonists, and possibly neurosteroids, may underlie ethanol dependence after multiple ethanol withdrawal episodes. These altered pharmacological properties are most consistent with changes in the subunit composition in the CA1 area of this rat model of alcohol dependence. 相似文献
110.
Amador García-Ramos Igor ?tirn Paulino Padial Javier Argüelles-Cienfuegos Blanca De la Fuente Vojko Strojnik Belén Feriche 《Journal of Sports Science and Medicine》2015,14(2):256-262
The objective of the study was to assess the use of maximum (Vmax) and final propulsive phase (FPV) bar velocity to predict jump height in the weighted jump squat. FPV was defined as the velocity reached just before bar acceleration was lower than gravity (-9.81 m·s-2). Vertical jump height was calculated from the take-off velocity (Vtake-off) provided by a force platform. Thirty swimmers belonging to the National Slovenian swimming team performed a jump squat incremental loading test, lifting 25%, 50%, 75% and 100% of body weight in a Smith machine. Jump performance was simultaneously monitored using an AMTI portable force platform and a linear velocity transducer attached to the barbell. Simple linear regression was used to estimate jump height from the Vmax and FPV recorded by the linear velocity transducer. Vmax (y = 16.577x - 16.384) was able to explain 93% of jump height variance with a standard error of the estimate of 1.47 cm. FPV (y = 12.828x - 6.504) was able to explain 91% of jump height variance with a standard error of the estimate of 1.66 cm. Despite that both variables resulted to be good predictors, heteroscedasticity in the differences between FPV and Vtake-off was observed (r2 = 0.307), while the differences between Vmax and Vtake-off were homogenously distributed (r2 = 0.071). These results suggest that Vmax is a valid tool for estimating vertical jump height in a loaded jump squat test performed in a Smith machine.
Key points
- Vertical jump height in the loaded jump squat can be estimated with acceptable precision from the maximum bar velocity recorded by a linear velocity transducer.
- The relationship between the point at which bar acceleration is less than -9.81 m·s-2 and the real take-off is affected by the velocity of movement.
- Mean propulsive velocity recorded by a linear velocity transducer does not appear to be optimal to monitor ballistic exercise performance.