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981.
982.
K Khalighi TJ Florin RW Peters SR Shorofsky MR Gold 《Canadian Metallurgical Quarterly》1997,20(6):1682-1685
In three patients with a defibrillator system consisting of a Ventak P2 pulse generator and an Endotak C transvenous lead, we observed distortion of intracardiac electrograms following defibrillator shocks for atrial arrhythmias. There was a transient marked widening of the intracardiac ventricular complexes resembling ventricular tachycardia. This phenomenon should be recognized when evaluating arrhythmic episodes. 相似文献
983.
984.
Hyperfractionated irradiation with or without concurrent chemotherapy for locally advanced head and neck cancer 总被引:1,自引:0,他引:1
DM Brizel ME Albers SR Fisher RL Scher WJ Richtsmeier V Hars SL George AT Huang LR Prosnitz 《Canadian Metallurgical Quarterly》1998,338(25):1798-1804
BACKGROUND: Radiotherapy is often the primary treatment for advanced head and neck cancer, but the rates of locoregional recurrence are high and survival is poor. We investigated whether hyperfractionated irradiation plus concurrent chemotherapy (combined treatment) is superior to hyperfractionated irradiation alone. METHODS: Patients with advanced head and neck cancer who were treated only with hyperfractionated irradiation received 125 cGy twice daily, for a total of 7500 cGy. Patients in the combined-treatment group received 125 cGy twice daily, for a total of 7000 cGy, and five days of treatment with 12 mg of cisplatin per square meter of body-surface area per day and 600 mg of fluorouracil per square meter per day during weeks 1 and 6 of irradiation. Two cycles of cisplatin and fluorouracil were given to most patients after the completion of radiotherapy. RESULTS: Of 122 patients who underwent randomization, 116 were included in the analysis. Most patients in both treatment groups had unresectable disease. The median follow-up was 41 months (range, 19 to 86). At three years the rate of overall survival was 55 percent in the combined-therapy group and 34 percent in the hyperfractionation group (P=0.07). The relapse-free survival rate was higher in the combined-treatment group (61 percent vs. 41 percent, P=0.08). The rate of locoregional control of disease at three years was 70 percent in the combined-treatment group and 44 percent in the hyperfractionation group (P=0.01). Confluent mucositis developed in 77 percent and 75 percent of the two groups, respectively. Severe complications occurred in three patients in the hyperfractionation group and five patients in the combined-treatment group. CONCLUSIONS: Combined treatment for advanced head and neck cancer is more efficacious and not more toxic than hyperfractionated irradiation alone. 相似文献
985.
S Srinath YC Janardhan Reddy SR Girimaji SP Seshadri DK Subbakrishna 《Canadian Metallurgical Quarterly》1998,98(6):437-442
In the light of new opportunities for structural arrangements in Germany calling for higher co-operation between physicians in private practice, determinants for diagnostic and therapeutic co-operation need to be examined. In the present study, 130 general practitioners were asked in regard to four typical primary care indication groups whether they prefer to diagnose and treat the patients on their own or in co-operation with colleagues. This self-assessment was validated using the data from 2,069 physician-patient contacts: physicians preferring therapy in co-operation actually referred patients three times more often. Concerning both gastro-intestinal and rheumatic disorders, physicians' preferences for diagnostic and therapeutic co-operation are highly correlated (phi = 0.491 and 0.528 respectively); preferences for diagnostic and therapeutic co-operation across indications are not as strongly correlated (phi = 0.334 and 0.397 respectively). However, there is no general indication-independent attitude towards co-operation for individual physicians: Indication and type of services are two factors which--probably in addition to others--affect co-operation independently. We confirm earlier conclusions that the detailed analysis of provider and patient characteristics together with the actual patient management on a case by case basis is a powerful tool for health services research. 相似文献
986.
SE Hearne PB Amsterdam WA Baker SR Sawchak HR Phillips MH Sketch JP Zidar 《Canadian Metallurgical Quarterly》1998,82(5):666-8, A6
This single-center review of a consecutive series of patients requiring reexamination by angiography within 1 week of a coronary stent placement due to chest pain reveals that patients treated with a poststent anticoagulation regimen of warfarin and aspirin, and those with lower poststent deployment dilation pressures, have an increased risk of subacute stent thrombosis. Repeat cardiac catheterization within the first week after coronary artery stent implantation should be reserved for patients with significant electrocardiographic changes. 相似文献
987.
Sixty-one women making slow progress in the active phase of spontaneous labour with intact membranes were randomised to oxytocin and amniotomy, amniotomy only or expectant management. The data show that oxytocin significantly increases the rate of cervical dilatation and shortens prolonged labour, when compared with amniotomy alone and expectant management (P = 0.0144 and 0.0006, respectively). The impact on the operative delivery rate and neonatal outcome is difficult to assess due to the small number of relevant adverse outcomes. Women reported higher satisfaction score in the two groups where intervention followed the diagnosis of dysfunctional labour. 相似文献
988.
989.
MA Walker J Schumacher DG Schmitz WC McMullen WW Ruoff MR Crabill JF Hawkins PM Hogan SR McClure JR Vacek JF Edwards RG Helman PF Frelier 《Canadian Metallurgical Quarterly》1998,212(6):848-851
Three adult horses underwent aggressive treatment of squamous cell carcinoma of the nasal cavity and paranasal sinuses, using course-fractionated cobalt 60 radiotherapy. Squamous cell carcinoma of the nasal cavity and paranasal sinuses is not commonly diagnosed in horses. Historically, horses with this type of neoplasm have not been treated or have undergone some form of surgery. The prognosis for long-term survival or cure has been poor. Long-term results of cobalt 60 radiotherapy were good to excellent and exceeded those usually reported for horses treated surgically. On the basis of these results, use of radiotherapy for these neoplasms is recommended. 相似文献
990.