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排序方式: 共有544条查询结果,搜索用时 15 毫秒
1.
David S. K. Lu Shantanu Sinha John Lucas Keyvan Farahani Robert Lufkin Klaus Lewin 《Journal of magnetic resonance imaging : JMRI》1997,7(2):303-308
The purpose of this study was to test the feasibility of MR-guided percutaneous ethanol ablation of liver tissue on a .2-T open MR scanner. Needles were placed by MR guidance first into an ex vivo sheep liver and then into livers of three anesthetized pigs, and injection of 10 ml of 96% alcohol was performed. T1 fast low-angle shot (FLASH), T2 turbo spin echo (TSE), and T1 spin echo (SE) images were obtained after incremental volumes of injection. In one pig, simultaneous injection of saline into normal liver was also performed with subsequent pathological correlation. Ethanol-infiltrated liver was hypointense to liver on all sequences, whereas saline caused no tissue signal changes on T1 SE and either isointense or hyperintense changes on T2 TSE images. Pathological examination confirmed ethanol-induced acute liver changes as compared with the control. MR guidance of needle placement and monitoring of ethanol effects on liver tissue is feasible. This may have implications for potential MR-guided hepatic tumor ablation. 相似文献
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Keyvan Karkouti Duminda N Wijeysundera Terrence M Yau Jeannie L Callum Massimiliano Meineri Marcin Wasowicz Stuart A McCluskey W. Scott Beattie 《Journal canadien d'anesthésie》2006,53(3):279-287
PURPOSE: To determine the independent relationship between leukoreduced platelet transfusions and adverse events in cardiac surgery. METHODS: In this observational study, detailed baseline and perioperative data were prospectively collected on consecutive patients who underwent cardiac surgery at a single institution from 1999 to 2004. The independent associations of platelet transfusion with clinical outcomes (low output syndrome, myocardial infarction, stroke, renal failure, sepsis, and death) were determined by multivariable logistic regression analysis and propensity score case-control analysis. RESULTS: Of the 11,459 patients analyzed, 2,174 (19%) received (leukoreduced) platelets - 1,408 received 5 U, 471 received 10 U, 140 received 15 U, and 155 received 20 or more units. Although all measured adverse event rates were higher in those who received platelets, in neither the logistic regression analyses nor the propensity score analyses was there any association between platelet transfusion and any of the adverse events. CONCLUSIONS: Transfusion of leukoreduced platelets in cardiac surgery is not associated with adverse clinical outcomes when adjustments are made for important confounders. 相似文献
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585-nm Pulsed Dye Laser in the Treatment of Surgical Scars Starting on the Suture Removal Day 总被引:2,自引:0,他引:2
Keyvan Nouri MD Gloria P. Jimenez MD Catherine Harrison-Balestra BA George W. Elgart MD 《Dermatologic surgery》2003,29(1):65-73
BACKGROUND: The optimal time frame to improve the quality and cosmetic appearance of scars by laser therapy has not been clearly elucidated by prior controlled clinical trials. OBJECTIVE: To determine the efficacy of the 585-nm pulsed dye laser (PDL) in the treatment of surgical scars starting on the day of suture removal. METHODS: Eleven patients (skin types I-IV) with 12 postoperative linear scars that were greater than 2 cm were treated three times on monthly intervals with the 585-nm PDL (450 micro s, 10-mm spot size, 3.5 J/cm2 with 10% overlap) on one scar half, whereas the other half received no treatment. Scars were later evaluated by a blinded examiner using the Vancouver Scar Scale (VSS) for pigmentation, vascularity, pliability, and height. Scars were then blindly examined for cosmetic appearance using a visual analog scale. RESULTS: One month after the last treatment, final scar analysis by the blinded examiner revealed a significant difference between treated and untreated sites, with the treated halves scoring better in all scar parameters in the VSS and in cosmetic appearance. The treated halves demonstrated an overall average improvement in the VSS between the first treatment score and the final score of 54% versus 10% in the controls (P=0.0002). The cosmetic appearance score (0=worst; 10=best) at final assessment was significantly better for the treated scars, scoring 7.3 versus the averaged control score of 5.2 (P=0.016). CONCLUSION: The 585-nm PDL is effective and safe in improving the quality and cosmetic appearance of surgical scars in skin types I-IV starting on the day of suture removal. 相似文献
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Reading Julian P.; Huffman John L.; Wu Joy C.; Palmer Frances T.; Harton Gary L.; Sisson Michael E.; Keyvanfar Keyvan; Gresinger Thomas H.; Cochrane William J.; Fallon Lee A.; Menapace-Drew Gianna F.; Cummings Emilie A.; Jones Shirley L.; Black Susan H.; Schulman Joseph D.; Levinson Gene 《Molecular human reproduction》1995,1(7):362-367
The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy 相似文献
6.
Disposable N95 respirator masks are the current standard for healthcare worker respiratory protection in the COVID-19 pandemic. In addition to shortages, qualitative fit testing can have low sensitivity for detecting poor fit, leading to inconsistent protection. Multiple groups have developed alternative solutions such as modified snorkel masks to overcome these limitations, but validation of these solutions has been lacking. We sought to determine if N95s and snorkel masks with attached high-efficiency filters provide consistent protection levels in healthcare workers and if the addition of positive pressure via an inexpensive powered-air purifying respirator to the snorkel mask would provide enhanced protection. Fifty-one healthcare workers who were qualitatively fitted with N95 masks underwent quantitative mask fit testing according to a simulated workplace exercise protocol. N95, snorkel masks with high-efficiency filters and snorkel masks with powered-air purifying respirators were tested. Respiratory filtration ratios were collected for each step and averaged to obtain an overall workplace protocol fit factor. Failure was defined as either an individual filtration ratio or an overall fit factor below 100. N95s and snorkel masks with high-efficiency filters failed one or more testing steps in 59% and 20% of participants, respectively, and 24% and 12% failed overall fit factors, respectively. The snorkel masks with powered-air purifying respirators had zero individual or overall failures. N95 and snorkel masks with high-efficiency filter respirators were found to provide inconsistent respiratory protection in healthcare workers. 相似文献
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Katlein França Anna Chacon Jennifer Ledon Jessica Savas Jan Izakovic Keyvan Nouri 《Lasers in medical science》2013,28(4):1197-1204
The use of laser to treat cutaneous lesions began with Dr. Leon Goldman and his coworkers in 1963. Ten years later, these authors described promising effects on angiomas using the continuous-wave neodymium:yttrium–aluminum–garnet laser. In 1983, Anderson et al. proposed the photothermolysis theory. The selective destruction of vascular lesions is based on this principle, and it is still a guide for treatment of vascular lesions. Over the past 25 years, laser treatment of cutaneous vascular lesions has progressed significantly. Vascular lasers such as argon, tunable dye, krypton, and copper vapor were used in the past and were associated not only with risk of scarring but also hyper- and hypopigmentation. Since then, new devices were developed in order to minimize these side effects. This article presents an overview and update of the current available treatment of cutaneous vascular lesions and covers future directions for vascular laser technology. 相似文献
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