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Cryosurgical ablation of accessory atrioventricular connections: a method for correction of the pre-excitation syndrome 总被引:3,自引:0,他引:3
JJ Gallagher WC Sealy RW Anderson J Kasell R Millar RW Campbell L Harrison EL Pritchett AG Wallace 《Canadian Metallurgical Quarterly》1977,55(3):471-479
Cryothermia, a new technique for definitive treatment of the pre-excitation syndrome, is described in two patients. The first patient presented with a normal P-R interval with a delta wave and reciprocating tachycardia. Preoperative electrophysiologic study suggested a free-wall atrioventricular connection on the left posterior atrioventricular (A-V) groove. At surgery, epicardial mapping confirmed the site of pre-excitation on the posterior left ventricular (LV) wall. An electrogram arising from the accessory pathway (AP) was recorded at the site of earliest ventricular activation. Interatrial delay combined with an apparently long accessory pathway to the ventricle caused the P-R interval to appear normal. Local pressure abolished pre-excitation. The site of early ventricular activation was cooled to -60 degrees C with a specially designed cryoprobe. All evidence of pre-excitation and arrhythmias disappeared. The second patient presented with a refractory reciprocating tachycardia and was found to have an AP in the septum capable of only retrograde conduction. Retrograde conduction was abolished by applying a temperature of 0 degrees C to the anulus at this site during tachycardia. Conduction over the AP and reciprocating tachycardia returned with rewarming. Ablation of the AP was obtained by applying a temperature of -60 degrees C for 90 seconds on two occasions to the same area. The His bundle was not injured. 相似文献
155.
BA Adamovich VV Borshchenko IaN Vernikov AG Prishchep AP Rogatovskaia 《Canadian Metallurgical Quarterly》1977,11(5):80-85
Hygienic processing of the underwear in a device combining mechanical treatment, forced pumping of the washing solution and wringing by compressed air can be used under special conditions. The basic parameters of the engineering process have been determined, viz.: the number of washing baths, temperature of the water, time of processing, etc. 相似文献
156.
This paper describes our experience over a period of 10 years (1966-76) with fractures showing non-union and delayed union. All were treated by the AO technique. The source of our patients, the management of their fractures and the results are described. From this experience we have drawn conclusions on which future policy will be based. 相似文献
157.
Amyloid in polypeptide hormone-producing tumors 总被引:2,自引:0,他引:2
P Westermark L Grimelius JM Polak LI Larsson S Van Noorden E Wilander AG Pearse 《Canadian Metallurgical Quarterly》1977,37(2):212-215
The hormone content of 72 endocrine tumors was determined by immunofluorescence and their amyloid content was investigated. Seventeen of the 72 tumors contained amyloid. Amyloid was frequently found in tumors producing calcitonin, insulin, or growth hormone, but was rarely found in other tumors. Thus, there is a relationship between the occurrence of amyloid in an endocrine tumor and the type of hormone it produces. The reason for this is not known, but there is evidence that the amyloid fibrils contain proteins related to the hormone produced by the tumors. 相似文献
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Cecilia A Svelander Evelina A Tibäck Lilia M Ahrné Maud IBC Langton Ulf SO Svanberg Marie AG Alminger 《Journal of the science of food and agriculture》2010,90(10):1665-1672
BACKGROUND: Human studies have demonstrated that processing of tomato can greatly increase lycopene bioavailability. However, the difference between processing methods is not widely investigated. In the current study different thermal treatments of tomato were evaluated with regard to their impact on in vitro bioaccessibility and retention of lycopene and β‐carotene as well as textural properties. Thermal treatments used were low (60 °C) and high (90 °C) temperature blanching followed by boiling. RESULTS: Lycopene was relatively stable during thermal treatment, whereas β‐carotene was significantly (P < 0.05) reduced by all heat treatments except for low temperature blanching. In vitro bioaccessibility of lycopene was significantly increased from 5.1 ± 0.2 to 9.2 ± 1.8 and 9.7 ± 0.6 mg kg?1 for low and high temperature blanching, respectively. An additional boiling step after blanching did not further improve lycopene bioaccessibility for any treatment, but significantly reduced the consistency of low temperature treated samples. CONCLUSION: Choice and order of processing treatments can have a large impact on both lycopene bioavailability and texture of tomato products. Further investigations are needed, but this study provides one of the first steps towards tomato products tailored to optimise nutritional benefits. Copyright © 2010 Society of Chemical Industry 相似文献