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951.
J Henderson J Chambers TA Jeddy J Chamberlain TA Whittingham 《Canadian Metallurgical Quarterly》1994,67(798):546-551
Percutaneous transluminal balloon angioplasty (PTA) of superficial femoral artery lesions is associated with similar initial success rates in coronary and iliac artery angioplasty but its application is limited by a much higher incidence of restenosis. To improve understanding of the trauma caused to the vessel by balloon angioplasty and the mechanisms contributing to the subsequent processes of healing and restenosis requires serial investigations of the treated arteries in vivo. This paper describes a prospective study using colour duplex ultrasonic imaging to assess arterial changes in 51 patients with atherosclerotic disease undergoing PTA of superficial femoral artery stenoses and occlusions. Each patient was scanned prior to angioplasty and at intervals up to 6 months post-angioplasty. On each scan, measurements were made of the overall vessel and lumen diameters at each site of angioplasty. These measurements indicate that angioplasty improves vessel patency mainly by stretching of the vessel wall, with compression and/or redistribution of the atherosclerotic plaque contributing less than 25% to the improvement of lumen diameter. Serial measurements after angioplasty show complex patterns of change at the angioplasty sites indicating that several mechanisms may be contributing to the processes of vessel healing and subsequent restenosis. Possible mechanisms which could explain the measured changes in overall vessel and lumen diameters are discussed. 相似文献
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FL Rice KM Albers BM Davis I Silos-Santiago GA Wilkinson AM LeMaster P Ernfors RJ Smeyne H Aldskogius HS Phillips M Barbacid TM DeChiara GD Yancopoulos CE Dunne BT Fundin 《Canadian Metallurgical Quarterly》1998,198(1):57-81
This study investigates discrepancy and congruence between doctors and patients in their beliefs about the need for medical treatment. One hundred seventy-six outpatients and 337 university students rated each of a set of 35 symptoms on the urgency with which they would seek medical advice were they experiencing that symptom. Sixty-six general practitioners rated the urgency with which a person experiencing that symptom should seek medical advice. These symptoms were classified as relatively serious or nonserious on the basis of ratings by a separate set of doctors. General practitioners perceived a greater overall need for treatment than did patients, but this difference was greater for nonserious than for serious symptoms. In fact patients perceived treatment to be more urgent for three serious symptoms, each potentially indicative of cancer. The observed pattern of doctor-patient discrepancies can be explained in terms of the availability heuristic. The role of this heuristic in the cognitive dynamics of doctor-patient relationships merits future attention. 相似文献
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Two groups of calves were subjected to dietary stress by withholding of food beginning 1 or 14 days after inoculation with 10(10) CFU of Escherichia coli O157:H7. Following treatment, neither group had a significant increase in fecal shedding of E. coli O157:H7. A third group of calves had food withheld for 48 h prior to inoculation with 10(7) CFU of E. coli O157:H7. These calves were more susceptible to infection and shed significantly more E. coli O157:H7 organisms than calves maintained on a normal diet. 相似文献
956.
MJ Costanza BT Heniford MJ Arca JT Mayes M Gagner 《Canadian Metallurgical Quarterly》1998,64(12):1121-5; discussion 1126-7
Break down after repair of recurrent ventral hernias can exceed 50 per cent. Laparoscopic techniques offer an alternative. This study evaluated the efficacy of the laparoscopic approach for recurrent ventral hernias. A retrospective review on all patients with a recurrent ventral hernia who underwent laparoscopic repair at our institution from August 1995 to June 1997 was performed. Demographic, operative, postoperative, and follow-up data were collected. Thirty-one patients underwent an attempted laparoscopic ventral hernia repair. Sixteen were for recurrent hernias; 15 were successfully repaired laparoscopically. The patients were typically obese (mean body mass index, 30 kg/m2), had an average of 2.4 previous open repairs (range, 1-7), and six patients had previously placed intra-abdominal mesh. An average of 3.5 (range, 1-16) defects were found per patient with a mean total hernia size of 130 cm2 (6-480 cm2). In all cases, expanded polytetrafluoroethylene mesh (average, 299 cm2) was secured with transabdominal sutures. Postoperatively patients required an average of 19 mg of narcotics (MSO4 equivalent). Bowel function returned in 1.7 days. Length of stay averaged 2.0 days (1-4 days). There were two complications: cellulitis, which resolved with antibiotics, and skin break-down, which required mesh removal. With follow-up averaging 18 months (7-29 months), there is one recurrence; the case in which the mesh was removed. Laparoscopic repair of recurrent ventral hernia seems promising. Decreased hospital stays, postoperative pain, wound complications, and a low rate of recurrence are benefits of this technique. 相似文献
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