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21.
D Balatsoukas C Hintschich V Klauss R M Huber 《Klinische Monatsbl?tter für Augenheilkunde》1992,201(4):211-215
The paper compares the preoperative localization of stenosis in the lacrimal passage after digital dacryocystography with the operative findings in 23 eyes of 22 patients in the years 1988 to 1991 at the Munich University Eye Hospital. In a very high percentage (95.6%) there is a positive correlation. The discussion shows the advantages of the method and includes a review of relevant literature. 相似文献
22.
Interventions in the sense of a surgical session according to SGB V are determined for the most part from the number of general anaesthetics induced for the department. The capacity of an operating theatre can be calculated from experience at 4–6 operations per day, that is to say 1,000 operations per year if 200 full operating days per year are assumed. If we assume that 80% of patients in the trauma surgery department do undergo operative treatment, that the average time each patient is then occupying a bed is 7 days, and that the rate of bed use is 85%, this means that for every 1,000 surgical operations an average of 28.3 beds must be reserved – as a rule of thumb, between 20 and 30 beds for each operating theatre. In Germany, 1000 surgical patients in a trauma surgery department means 200 injured as defined by GUV; on average the injuries are serious in 25% of these cases. Speed in trauma surgery is defined in increments of 1,000 operations performed per year. Thus, double speed means 2,000 operative cases per year, two operating theatres in constant use and the treatment of 500 seriously injured patients needing trauma surgery. The rough figures mentioned can be used as a quantifiable basis for estimation of the performance structure of trauma surgery departments in Germany. 相似文献
23.
Jie Lian Dirk Müssig Volker Lang 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(7):506-513
AIMS: To quantitatively compare the ventricular rate-smoothing (VRS) effects of different ventricular pacing (VP) protocols for atrial fibrillation (AF). METHODS AND RESULTS: Using a recently developed open-source model that can simulate the ventricular response in AF and VP, the performance of fixed-rate pacing and four previously published VRS algorithms were assessed by the mean RR (mRR), the root mean square of successive RR differences (RMSSD), the percentage of ventricular senses (VS%), and the percentage of short RR intervals (sRR%). All pacing protocols cause rate-dependent reduction of RMSSD, VS%, and sRR% with or without shortening of mRR compared to spontaneous AF. Fixed-rate pacing was more sensitive to the intrinsic rate than the VRS algorithms. The performance was generally comparable between different VRS algorithms, although higher mRR and VS% can be achieved at the expense of larger RMSSD and sRR%. CONCLUSION: The effect of VP on ventricular rhythm in AF depends on both intrinsic rate and the aggressiveness of the pacing protocol. Adequate rate control is necessary for effective operation of the VRS algorithm. Choosing VRS algorithm should balance between the beneficial effects of rate regularization and the negative effects of increasing heart rate and percentage of VP. 相似文献
24.
25.
Daniel Klase Stefan Gottschalk Erich Reusche Christian Hagel Einar Goebel Volker Tronnier Alf Giese 《Child's nervous system》2007,23(8):907-912
CASE REPORT: The reported female patient underwent sub-total resection of an intra-medullary cervicothoracic astrocytoma classified as WHO grade II in 1984 at the age of 18 months and received local irradiation. In 1989, a local recurrence was diagnosed and a partial resection was performed. Sixteen years later, a small recurrent cervicothoracic tumour was found and spinal seeding to the equine nerve roots and the left cerebellar cortex was apparent on MRI. The patient was implanted with a ventriculoperitoneal shunt for a pseudo-tumour cerebri producing papilloedema, which eventually lead to amaurosis. After an extended biopsy, the invasive lumbosacral tumour was classified as glioblastoma multiforme. Two months later, the patient died after rapid progression of the caudal cranial nerve dysfunction. DISCUSSION AND CONCLUSION: Anaplastic progression and dissemination of spinal astrocytomas even two decades after initial diagnosis and treatment are rare. Therapies and diagnostic follow-up strategies are discussed. 相似文献
26.
27.
Joachim H?chel D?rte Lehmann Claudia Fehrenberg Volker Unger David A Groneberg Christian Grosse-Siestrup 《Nephrology, dialysis, transplantation》2003,18(9):1748-1754
BACKGROUND: The isolated perfused canine kidney has been established as a valid model for conducting both renal physiology and transplantation research. This model is of particular importance for developing new strategies to improve graft function after renal transplantation. In the present study, a newly developed method using isolated haemoperfused porcine kidneys was adapted for use in canine kidneys. In contrast to haemoperfusion, synthetic perfusion media can be standardized and can prevent the initiation of blood-mediated reperfusion reactions. Thus, an additional aim was to determine whether blood could be replaced by synthetic cell-free perfusion solutions. METHODS: Canine kidneys (n = 30) were harvested from donors euthanized in veterinary practices for causes unrelated to the present study. The kidneys were isolated and perfused with autologous blood or cell-free synthetic electrolyte buffer (Tyrode solution). During perfusion, we monitored renal perfusate flow (RPF), glomerular filtration rate (GFR), electrolyte and glucose reabsorption, oxygen consumption and urine concentration. RESULTS: Changes in perfusion medium did not affect the RPF. In contrast, GFR, urine concentration and oxygen consumption were significantly higher, whereas fractional excretion of sodium and glucose were significantly lower in blood- than in Tyrode-perfused kidneys. CONCLUSIONS: This system offers a simple model for studying whole-organ functional alterations after acute renal ischaemia. Renal function indicators were below values reported during in vivo physiological conditions. These functions were better conserved when kidneys were perfused with autologous blood than with Tyrode. 相似文献
28.
Wolfram Grimm Jens Winzenburg Ursula Knop Jürgen Hoffmann Volker Menz Frank Grote Bernhard Maisch 《Annals of noninvasive electrocardiology》1997,2(1):20-26
Objective: This prospective study was designed to compare incidence and clinical significance of ventricular late potentials between patients with idiopathic dilated cardiomyopathy (IDC) and postinfarct patients (CAD) using exactly the same method of signal-averaged electrocardiography (SAECG) in both patient groups. Methods: Time-domain analysis of SAECG was performed in 120 consecutive patients with IDC, 120 patients with CAD, and 60 healthy controls. Ventricular late potentials were detected in 27 of 120 patients with IDC (23%) compared to 41 of 120 patients with CAD (34%; P < 0.05). Results: Ventricular late potentials were found in 2 of 60 controls (3%). During 15 ± 7 months follow-up, serious arrhythmic events occurred in 17 of 120 patients with IDC (14%) and in 13 of 120 patients with CAD (11%). The sensitivity of ventricular late potentials for future arrhythmic events was 35% for IDC compared to 77% for CAD (P < 0.05). The positive predictive value of late potentials detected by time-domain analysis was 22% for IDC versus 24% for CAD (P = ns). Conclusion: In this selected patient population with IDC and CAD, time-domain analysis of SAECG revealed a lower incidence of ventricular ate potentials in patients with IDC as compared to postinfarct patients. Whereas ventricular late potentials had a high sensitivity but a low positive predictive value for identification of postinfarct patients with serious arrhythmic events during follow-up, both sensitivity and positive predictive value of ventricular late potentials for future serious arrhythmic events were low in the setting of IDC. 相似文献
29.
There is some controversy over the treatment of acromioclavicular injuries. The use of the Rockwood classification as the basis for decisions on whether operative or nonoperative treatment is indicated is discussed critically, and the authors' preferred operative technique is described and illustrated by examples. We treat injuries classified according to the Rockwood classification as types I and II with conservative methods. In type III injuries the patient's age, job and free time activities determine whether or not surgery is indicated. In the case of type IV or type VI injuries we always perform temporary internal fixation of the acromioclavicular joint, using transarticular K-wire fixation or hookplate osteosynthesis. Satisfactory results of both operative and nonoperative treatment are reported in the literature. The authors' own results are presented. 相似文献
30.
Steffen Roiner Nikolas Bakinde Ulrike Zeitschel Reinhard Schliebs Volker Bigl 《International journal of developmental neuroscience》1998,16(7-8):669-673
The present study was conducted to test the hypothesis that cholinergic basalforebrain neurons are a major source of cerebrospinal fluid (CSF) cholinesterases. To address thisquestion enzyme activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inboth CSF and parietal cortex were assayed following selective lesion of basal forebrain cholinergicneurons by a single intracerebroventricular application of the cholinergic immunotoxin192IgG-saporin. Cholinergic immunolesions led to a dramatic decrease in total AChE activity inparietal cortex, which was due to the specific loss of the G4 molecular form while the activity ofthe G1 form was increased as compared to nonlesioned animals. In contrast, the total enzymeactivity of BChE and its molecular forms were not affected by cholinergic lesion in both parietalcortex and CSF. The data suggest, that cholinergic basal forebrain neurons are seemingly not amajor source of cholinesterases in the CSF, and do not provide any evidence for using CSFcholinesterases as a diagnostic marker of basal forebrain cholinergic cell loss in humans. 相似文献