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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
2.
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
3.
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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Pretibial lacerations are a common soft tissue injury especially amongst elderly women. An alternative repair approach to this problem is described. The traumatized and often necrosed-looking flap of skin from the injured area is made into a full thickness 'fenestrated' skin graft to cover the defect. Experience of 30 cases shows the method to be useful for accident and emergency departments as well as surgical units. The healing time is shorter than in conservative methods and similar to 'meshed split skin grafting' as an out-patient procedure, but the great advantage is the absence of a donor site. 相似文献
7.
Identification of tumour-specific peptide(s) hidden within the groove of human leucocyte antigens is a crucial prerequisite for peptide vaccine therapy. Conventionally, the peptide(s) are isolated by mild acid extraction (MA) technique followed by sequential ultra-filtrations. Here we describe a new approach for peptide isolation using the immunobead purification (IB-P) technique in conjunction with reverse-phase high-performance liquid chromatography. The obtained data were validated by SDS-PAGE followed by the silver staining technique. The results can be summarised as follows: (1) Comparison of class I-associated peptides isolated from a bladder cell line before and after the correction of class I antigens by gene transfection followed by IB-P technique showed the presence of peptides only from the class I-corrected cells. The data were confirmed using the silver staining technique as a way of detecting individual peptide bands. (2) Whilst peptides could be isolated by both techniques, the MA method led to the isolation of peptides from both class I-negative and class I-positive Fen cell lysates. (3) The IB-P approach could be used for isolation of class I-associated peptides from a normal kidney tissue. The data showed the high efficiency of the IB-P approach for isolation of class I-associated peptides. Unlike the MA technique, where the presence of non- class I-associated peptides was a problem, the IB-P approach isolated only peptides associated with the class I antigens. In addition, the data showed the feasibility of extracting peptides from tissue fragments by the IB-P method. The approach presented here may assist the future development of peptide vaccine therapy in urological cancers. 相似文献
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Interleukin-2 reverses deficient cell-mediated immune responses in rheumatoid arthritis 总被引:8,自引:9,他引:8 下载免费PDF全文
The depressed cell-mediated immunity in rheumatoid arthritis was investigated in vivo by cutaneous hypersensitivity responses to seven antigens including tuberculin PPD, and in vitro by lymphocyte transformation to the latter antigen. In vivo 40% of rheumatoid patients were anergic compared to 2% of controls (P less than 0.001) with an associated reduction in sum score (5.9 +/- 6.5 vs 15.3 +/- 8.7, P less than 0.001). In vitro lymphocyte proliferation to PPD was also significantly depressed (P less than 0.001) and could not be reversed by indomethacin. A significant correlation between the in vivo sum scored (induration in mm) and in vitro thymidine incorporation (d/min) (r = 0.59, P less than 0.001) was found. In an attempt to overcome the depressed in vitro response the addition of a crude supernatant from a mixed lymphocyte reaction was found to return the PPD stimulated lymphocyte proliferation to the normal range. This effect was mimicked by purified IL-2 but not purified IL-1. The implications of this finding are are discussed. 相似文献
10.
Comparison of the inhibition by glucocorticosteroids and cyclosporin A of mitogen-stimulated human lymphocyte proliferation. 总被引:2,自引:0,他引:2 下载免费PDF全文
We examined the effects of dexamethasone, hydrocortisone and cyclosporin A (CyA), alone and in combination, on tritiated thymidine (3H-TdR) incorporation into human blood mononuclear cells stimulated by phytohaemagglutinin (PHA), pokeweed mitogen (PWM) and phorbol myristic acetate (PMA). Pharmacological concentrations of glucocorticosteroids displaced the PHA and PWM dose-response curves to the right, but the same maximum response was achieved indicating selective inhibition at suboptimal levels of stimulation. In contrast, steroid inhibition of PMA-stimulated cells was not mitogen dose-dependent and the maximum response was clearly depressed. In the case of CyA, the stimulation by all three mitogens was inhibited in the latter fashion, but 10-fold higher concentrations were required to inhibit PMA-stimulated cells compared with PHA- and PWM-stimulated cells. These results suggest that a steroid-sensitive mechanism or lymphocyte sub-population may be selectively activated by PMA and by low doses of PHA and PWM, while the different inhibition profile observed for CyA might be taken to indicate that this drug affects a separate subpopulation and that PMA activation occurs later than the CyA-sensitive stage. Predominantly synergistic effects were obtained when the drugs were used together, thus providing an experimental basis for combination therapy in the treatment of reactions involving multiple lymphocyte activation mechanisms. 相似文献