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141.
The aim of the study was to evaluate whether complication rate, costs, operation times, and hospitalization times differed in two different patient groups: in group 1, frozen section analysis of the sentinel lymph node and lymph node dissection were carried out in the same operation. In group 2, normal investigation of the sentinel lymph node and lymph node dissection were done in a second operation. One hundred thirty-five patients with cutaneous melanoma were included. Hospitalization times, costs, complication rates, and operation times of two-stage and one-stage lymph node dissection of the draining area after detection of metastases in the sentinel lymph node were retrospectively compared. Lymph node metastasis in the sentinel lymph node was found in 23 patients. In 11 patients, removal of the sentinel lymph node and dissection of the lymph node basin was performed in the same operation. In 12 patients, a two-stage procedure was the treatment of choice. Operation times were not different in the two groups (p=0.87) while two-stage operation patients were hospitalized significantly longer (14.2 ± 9.7 vs 23.9 ± 24 days; p=0.01) and costs were significantly higher (7,836.90 ± 2,397.95 Swiss francs vs 5,279.40 ± 1,994.90 Swiss francs). In addition, more complications were found in the two-stage group.  相似文献   
142.
Management of Patients After Catheter Ablation of Ventricular Tachycardia   总被引:1,自引:0,他引:1  
The management of patients after catheter ablation of ventricular tachycardia is not well defined. In this article we summarize recently published results and report our own experience. Factors influencing the clinical outcome of these patients and methods to identify patients with an increased risk of recurrence of ventricular tachycardia are discussed. Furthermore, a review is given on current concomitant therapeutic tools including antiarrhythmic drugs and the implantation of an automatic cardioverter defibrillator.  相似文献   
143.
Effect of titanium surface texture on the cell-biomaterial interface.   总被引:1,自引:0,他引:1  
To improve the in vivo performance of engineered implants, this study examines the independent effects of surface chemistry and topography on fibroblast morphology and density in vitro. Titanium (Ti) was sputter-coated onto smooth and microtextured polyethylene terephthalate (PET). Test specimens were evaluated in 24-h, fibroblast cultures and assessed with scanning electron microscopy (SEM) for cellular morphology and density. Fibroblast density increased, as the Ti film thickness increased. The fibroblasts exhibited contact guidance on the textured test specimens. The greatest cellular density was found on the Ti-coated, textured test specimens. In conclusion, Ti and surface texture appeared to strongly influence fibroblast density and morphology as compared to PET and smooth surfaces.  相似文献   
144.
The zone of progenitor cells of mandibular condyles of neonatal mice was kept in an organ culture system for up to 8 days. Qualitative and quantitative determinations indicated a pronounced proliferative activity during the initial phases of the culture followed by a differentiation phase and the acquisition of typical hyaline cartilage. The mature hypertrophic chondrocytes were found to be surrounded by cartilage-specific macromolecules such as type II collagen, cartilage proteoglycans, and cartilage anchorin. The extracellular mineralization proceeded along matrix vesicles as is usually noted in vivo. A unique finding in this study was the observation that explants comprising cartilage progenitor cells and their adjacent extracellular matrix succeeded in repairing the damaged condylar in vitro.  相似文献   
145.
During 1986 and 1987, 47 patients with renal cell carcinoma were evaluated preoperatively with CT, angiography and MRI. The preoperative tumor stage (T), lymph node metastases and venous involvement determined with the three methods were compared to the operative and histopathological findings. For T stage, angiography proved less accurate (54%) than CT (64%) or MRI (63%). MRI was found to be superior to CT in assessing lymph nodes, with an overall accuracy of 89% and sensitivity of 100% compared to 77 and 60%, respectively, of CT. For venous involvement CT was overall more accurate (74%) than angiography (65%) or MRI (63%). All three methods expressed a low sensitivity (between 31 and 41%) and a high specificity (between 95 and 100%) for detecting venous involvement. The minimal advantages of MRI compared to its high cost do not justify its routine use. CT remains the method of choice in staging preoperatively renal cell carcinoma.  相似文献   
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148.
The results obtained in the analysis of 130 thrombocytopenic patients with a radioimmunoassay (RIA) for platelet-associated IgG (PA-IgG) and the platelet suspension immunofluorescence test (PIFT) were compared. The RIA was positive in 33 of 41 (82.9%) patients with idiopathic thrombocytopenia (ITP) and in 51 of 79 (64.4%) patients with secondary thrombocytopenia (STP). The PIFT was positive in 37 of the 41 (90.2%) ITP patients and in 57 of the 79 (72.2%) STP patients. Sensitivity and specificity for the diagnosis of ITP of both tests were comparable: 82.9 and 40.9% for the PA-IgG(RIA) and 90.2 and 36.7% for the PIFT. A significant positive correlation was observed between the mean amount of PA-IgG measured and the height of PIFT scores with anti-IgG. Of 38 discrepancies between PA-IgG(RIA) and PIFT with anti-IgG, 15 were due to borderline results, 17 were associated with abnormal platelet-size distribution and 20 were associated with occurrence of IgM antibodies. These results suggest influences of platelet fragments and/or aggregates on accurate measurement of PA-IgG. Both fragments and aggregates escape from accurate platelet counting, while their contribution to the total IgG content remains. Therefore, a falsely elevated PA-IgG (RIA) may be measured.  相似文献   
149.
We retrospectively reviewed records of 551 patients with clinical Stage C prostatic adenocarcinoma treated with 60 to 70 Gy external beam radiation. Elective pelvic node irradiation was given to 247 patients (45%). Follow-up for all surviving patients ranged from 16 to 201 months (median, 6.5 years; mean, 7 years). The 5-, 10-, and 15-year uncorrected actuarial survival rates were 72%, 47%, and 27%, respectively. Disease-free survival rates were 59%, 46%, and 40% at the corresponding times. Actuarial local control rates were 88%, 81%, and 75% at 5, 10, and 15 years, respectively. Disease-free survival was adversely affected by high pathologic grade, disease fixed to the pelvic sidewall, invasion of the bladder, prior transurethral resection, hydronephrosis, and elevated serum levels of prostatic acid phosphatase and creatinine. Elective pelvic node irradiation did not improve the outcome. Complications of treatment were acceptable: minor anorectal and/or urinary symptoms, 11%; mild to moderate complications, 19%; serious problems requiring surgery, 3%. It is concluded that localized, high-energy external beam irradiation provides excellent local control of disease, low morbidity, and 5-, 10-, and 15-year survival rates that have not been rivaled by other treatment.  相似文献   
150.
ZusammenfassungHintergrund Lernstörungen werden zunehmend auf Defizite bei der Sprachwahrnehmung und diese wiederum auf eine Verlangsamung der auditiven Verarbeitungsgeschwindigkeit zurückgeführt. In der Studie wird untersucht, ob sich bei Kindern mit Schulproblemen sprachliche Leistungen durch ein Zeitverarbeitungstraining verbessern lassen.Patienten und Methoden Bei 21 Kindern mit spezifischen Lernstörungen wurden über 8 Wochen Ordnungsschwelle und Richtungshören trainiert und im Vergleich zu einer Kontrollgruppe (n=21) Sprachleistungen bis 6 Monate danach überprüft.Ergebnisse Leistungssteigerungen wurden hinsichtlich der Ordnungsschwelle, nicht aber der sprachlichen Fähigkeiten beobachtet. Die Eltern schätzten die Wirkung des Trainings eher positiv ein.Schlussfolgerungen Ein Zeitverarbeitungstraining verbessert unmittelbar geübte Leistungen, nicht aber sprachliche Fähigkeiten. Von den Eltern wahrgenommene Verbesserungen sind nicht objektivierbar und als unspezifische Effekte zu bewerten. Die Ergebnisse sprechen insgesamt gegen die Wirksamkeit eines Zeitverarbeitungstrainings bei Kindern mit Schulschwierigkeiten.  相似文献   
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