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排序方式: 共有1574条查询结果,搜索用时 19 毫秒
991.
Assessment of a novel angiographic image stabilization system for percutaneous coronary intervention
Boyle AJ Chan MY Dib J Kapur NK Kraft S Vaillant R Whiting JS Resar JR 《Journal of interventional cardiology》2007,20(2):153-157
BACKGROUND: Optimization of coronary images for percutaneous coronary intervention (PCI) remains difficult due to cardiac motion throughout the respiratory and cardiac cycles. We tested a novel system to stabilize angiographic images at the region of interest in order to assist during PCI. METHODS: Patients undergoing PCI to the right coronary artery (RCA) (group 1, n = 22) or complex PCI (group 2, n = 16) were prospectively enrolled and the angiographic image sequences of patients who died suddenly of confirmed or presumed stent thrombosis following PCI (group 3, n = 16) were retrospectively reviewed. All image sequences were analyzed off-line by three cardiologists before and after image stabilization for accuracy of stent placement, presence of residual edge dissection, and adequacy of procedural outcome. RESULTS: Image stabilization was successful in 100% of cases in a mean time of 95 +/- 71 seconds and was considered to be helpful in 13.6% of group 1, in 18.3% of group 2, and in 10% of group 3 cases. There was good correlation between observers with a kappa statistic of 0.85 to 1.0 for all observations. However, there was no difference in the reviewers' opinions of stent placement, presence of edge dissection, or adequacy of procedural result when comparing the standard angiographic views and the stabilized images. In particular, no previously unrecognized edge dissections were apparent in group 3 with stabilized display. CONCLUSION: Image stabilization centered on the region of interest was considered helpful in a small subset of patients, particularly the complex PCI patients. However, no differences in objective parameters could be demonstrated. 相似文献
992.
Barbeau EJ Taylor MJ Regis J Marquis P Chauvel P Liégeois-Chauvel C 《Cerebral cortex (New York, N.Y. : 1991)》2008,18(5):997-1009
To better understand face recognition, it is necessary to identify not only which brain structures are implicated but also the dynamics of the neuronal activity in these structures. Latencies can then be compared to unravel the temporal dynamics of information processing at the distributed network level. To achieve high spatial and temporal resolution, we used intracerebral recordings in epileptic subjects while they performed a famous/unfamiliar face recognition task. The first components peaked at 110 ms in the fusiform gyrus (FG) and simultaneously in the inferior frontal gyrus, suggesting the early establishment of a large-scale network. This was followed by components peaking at 160 ms in 2 areas along the FG. Important stages of distributed parallel processes ensued at 240 and 360 ms involving up to 6 regions along the ventral visual pathway. The final components peaked at 480 ms in the hippocampus. These stages largely overlapped. Importantly, event-related potentials to famous faces differed from unfamiliar faces and control stimuli in all medial temporal lobe structures. The network was bilateral but more right sided. Thus, recognition of famous faces takes place through the establishment of a complex set of local and distributed processes that interact dynamically and may be an emergent property of these interactions. 相似文献
993.
Bostrom M O'Keefe R;Implant Wear Symposium Biologic Work Group 《The Journal of the American Academy of Orthopaedic Surgeons》2008,16(Z1):S63-S67
Understanding the complex cellular and tissue mechanisms and interactions resulting in periprosthetic osteolysis requires a number of experimental approaches, each of which has its own set of advantages and limitations. In vitro models allow for the isolation of individual cell populations and have furthered our understanding of particle-cell interactions; however, they are limited because they do not mimic the complex tissue environment in which multiple cell interactions occur. In vivo animal models investigate the tissue interactions associated with periprosthetic osteolysis, but the choice of species and whether the implant system is subjected to mechanical load or to unloaded conditions are critical in assessing whether these models can be extrapolated to the clinical condition. Rigid analysis of retrieved tissue from clinical cases of osteolysis offers a different approach to studying the biologic process of osteolysis, but it is limited in that the tissue analyzed represents the end-stage of this process and, thus, may not reflect this process adequately. 相似文献
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995.
Carine Le Bourvellec Karima Bouzerzour Christian Ginies Sylvaine Regis Yves Plé Catherine M.G.C. Renard 《Journal of food composition and analysis》2011,24(4-5):537-547
Apple fruit is well known for its health properties, ascribed to its content in both phenolics and fibres. As more and more apples are consumed after processing, there is a need to understand the impact of the conventional process on the nutritional potential of applesauce. We have investigated the variation in composition between fresh and processed apples of 12 cultivars, focussing on polysaccharides and polyphenols. The polysaccharide content estimated in the alcohol insoluble solid (AIS) of the apple flesh varied from 17 (cv. Greensleeves, obtention TMR 7 A 82) to 25 (cv. Jolyne) mg/g fresh weight. The AIS contents varied from 15 to 32 mg/g fresh weight in applesauce. The applesauces were fractionated into serum, containing low concentrations (<5 mg/g) of soluble fibres, and particles concentrating the fibres (40–60 mg/g) and the cellulose (>30% of the AIS). Total phenolic concentrations varied in the flesh from 578 (cv. Golden Delicious) to 1596 mg/kg fresh weight (cv. 3535), and in the peel from 1658 (cv. Greensleeves) to 7658 mg/kg fresh weight (cv. Sinta). The applesauces contained flavonols, coming from the skin, and slightly higher concentration of dihydrochalcones coming from the pips than the flesh. A dihydrochalcone oxidation product was also detected. The concentration of hydroxycinnamic acids and flavan-3-ols was decreased in proportions depending on the cultivar. The flavan-3-ols were concentrated in the particles of the applesauce. The composition of applesauce thus appeared to be very close to that of apple flesh. 相似文献
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999.
Véronique Fournier Denis Berthiau Julie d’Haussy Philippe Bataille 《Medicine, health care, and philosophy》2013,16(1):55-68
Is there any ethical justification for limiting the reproductive autonomy and not make assisted reproductive technologies available to certain prospective parents? We present and discuss the results of an interdisciplinary clinical ethics study concerning access to assisted reproductive technologies (ART) in situations which are considered as ethically problematic in France (overage or sick parents, surrogate motherhood). The study focused on the arguments that people in these situations put forward when requesting access to ART. It shows that requester’s arguments are based on sound ethical values, and that their legitimacy is at least as strong as that of those used by doctors to question access to ART. Results reveal that the three implicit normative arguments that founded the law in 1994, which are still in force after the bioethics law revision in July 2011—the welfare of the child, the illegitimacy of a “right to a child,” and the defense of the so called “social order”—are challenged on several grounds by requesters as reasons for limiting their reproductive autonomy. Although these results are limited to exceptional situations, they are of special interest insofar as they give voice to the requesters’ own ethical concerns in the ongoing political debate over access to ART. 相似文献
1000.