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61.
Zusammenfassung Die chirurgische Erstbehandlung des primären Hyperparathyreoidismus (pHPT) ist bei adäquater Expertise nahezu immer erfolgreich. Reoperationen sind eine besondere Herausforderung für den Chirurgen, ein hohes Risiko für den Patienten und seltener erfolgreich als Erstoperationen. In dieser Übersicht werden die Gründe für erfolglose Erstoperationen, die wichtigsten Punkte der Vorbereitung und Durchführung von Reoperationen und die dafür erforderlichen technischen und personellen Voraussetzungen diskutiert. Standardisiertes Vorgehen und entsprechende Erfahrung sowie zeitgemäße technische Ausstattung vorausgesetzt, ist bei Reoperationen beim pHPT häufiger als früher eine dauerhafte Beseitigung der Hyperkalzämie zu erreichen.Neben der weiterhin uneingeschränkt gültigen Erkenntnis, dass der beste Schutz vor einer Reoperation und den sie begleitenden Komplikationen der durch die Kenntnisse des Operateurs erreichte Erfolg der ersten Operation ist, muss erneut unterstrichen werden, dass Reoperationen nur in Kliniken mit einer speziellen Expertise durchgeführt werden sollten.  相似文献   
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INTRODUCTION: Esophagojejunostomy after total gastrectomy still remains a high risk anastomosis with a considerable morbidity and mortality. The majority of these anastomoses are performed by the intraluminal stapler technique, yet stenoses are a known late complication even after an uneventful postoperative course. In the present study, the osophagojejunostomy with the biofragmentable anastomosis ring (BAR) was examined in dogs. METHODS: 28 dogs were randomized into a group of manual suture (n = 14) and a BAR-group (n = 14). After gastrectomy, the esophagojejunostomy was performed by hand-suture with polypropylene 4-0 in the manual suture group, and with the 25/1.5 mm BAR in the BAR-group. In both groups the Roux-en-Y jejunojejunostomy was performed by hand-suture. The dogs were evaluated on postoperative days 4, 7 and 14 with regard to macroscopy, bursting strength, tissue hydroxyproline and histology. RESULTS: There was one leakage without clinical effect in the hand-sewn group on postoperative day 4; there was no leak in the BAR-group. In observing fibre-free enteral feeding, neither functional disorders nor obstruction of the BAR were observed. The general anastomosis parameters were matchable between the groups. CONCLUSION: The infracarinal BAR-esophagojejunostomy is comparable to the hand-sewn anastomosis in the dog-model.  相似文献   
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Eccentric fixation in Stargardt's disease assessed by Tübingen perimetry   总被引:1,自引:0,他引:1  
PURPOSE: To measure eccentric fixation characteristics in visual fields of patients with Stargardt's disease. METHODS: The positions of fixation loci (FL) in the visual field were determined by Tübingen perimetry (TP), using the position of the blind spots in 173 patients. Altogether, 669 visual fields were measured at baseline and during follow-up. Twenty patients were also examined by scanning laser ophthalmoscope (SLO). RESULTS: Ninety-five of 173 patients showed a ring scotoma with central fixation in at least one test, which could persist for up to 18.8 years. The median age for a 50% chance of the development of eccentric fixation was 23.6 years. One hundred four patients (203 eyes) used eccentric fixation in at least one eye; in 154 eyes, the FL was placed below the scotoma and in 33 eyes to the left of it, in 11 to the right of it, and in 5 above it. Once the FL was chosen, it remained within the same visual field area at subsequent tests, varying on average by 1.76 degrees. Compared with SLO results, the mean distance between FL and PRL was 1.90 degrees. CONCLUSIONS: It is possible to determine the position of the FL by perimetry with sufficient accuracy if the blind spot is well delimited. Stargardt patients can keep central fixation for different time intervals before changing to an eccentric FL. Most of them show an FL below the central scotoma, which is considered favorable for horizontal reading.  相似文献   
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BACKGROUND: We tested whether or not heart rate variability (HRV) changes can serve as early signs of ventricular tachycardia (VT) and predict slow and fast VT in patients with an implantable cardioverter defibrillator (ICD). METHODS AND RESULTS: We studied the ICD stored 1000 beat-to-beat intervals before the onset of VT (131 episodes) and during a control time without VT (74 series) in 63 chronic heart failure ICD patients. Standard HRV parameters as well as two nonlinear parameters, namely 'Polvar10' from symbolic dynamics and the finite time growth rates 'Fitgra9' were calculated. Comparing the control and the VT series, no linear HRV parameter showed a significant difference. The nonlinear parameters detected a significant increase in short phases with low variability before the onset of VT (for time series with less than 10% ectopy, P<0.05). Subdividing VT into fast (cycle length 270 ms) events, we found that the onset of slow VT was characterized by a significant increase in heart rate, whereas fast VT was triggered during decreased heart rates, compared to the control series. CONCLUSIONS: Our data may permit the development of automatic ICD algorithms based on nonlinear dynamic HRV parameters to predict VT before it starts. Furthermore, they may facilitate improved prevention strategies.  相似文献   
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The ARTIST trial demonstrated a worse outcome for patients with in-stent restenosis (ISR) treated with rotational atherectomy (RA) and adjunctive balloon angioplasty (PTCA) as compared to PTCA alone. This intravascular ultrasound (IVUS) substudy compares effects of lumen enlargement and examines reasons for failure of RA in this setting. IVUS (n = 56) was performed after each interventional step and at follow-up. Volumetric lumen gain measured 79 +/- 68 mm(3) after PTCA (13 +/- 4 atm) as compared to 44 +/- 26 mm(3) after RA and adjunctive PTCA (7 +/- 3 atm; P < 0.0001). RA itself enlarged lumen by only 19 +/- 17 mm(3) and stent volume was 47% smaller as compared to high-pressure PTCA. Low-pressure strategy after RA did not prevent tissue growth during follow-up (19 +/- 25 vs. 36 +/- 38 mm(3); RA vs. PTCA; P = 0.09). Consequently, net lumen gain after PTCA was 82% higher compared to RA (46 +/- 54 vs. 25 +/- 24 mm(3); P = 0.09). Further stent expansion is the key mechanism to achieve luminal gain by PTCA of ISR. Neointimal ablation by RA has only minor effects. Low-pressure PTCA does not prevent recurrent tissue growth and failed for treatment of ISR due to insufficient stent expansion.  相似文献   
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Despite a significant increase in the size of the Asian American elderly population, little is known about their social service needs and the level of service being provided them. This study used a survey methodology to examine all Asian American senior programs (N = 20) in a major American metropolitan region. The response rate was 90% with respondent agencies serving as the unit of analysis. Findings suggest that Asian elderly clients were primarily women and 'old-old', and that many of them were on SSI. Services provided were primarily tangible and facilitative, rather than clinical. Services needed but not provided were emergency psychiatric care, home attendants, home-delivered meals, legal services, medical services, and protective services. Findings of this study provide useful information for further research and program planning for Asian American elders in urban settings.  相似文献   
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