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971.
BACKGROUND: Currently the influence of age on corneal and ocular aberrations is still insufficiently known. The aim of this clinical study was to compare age-related aberrations of human eyes. METHODS: In a prospective study 98 eyes of 49 healthy patients ranging from 17 to 65 years of age (38.6+/-10.0 years) were consecutively examined. The best corrected visual acuity ranged from 0.8 to 1.6; 48 eyes were emmetropic (SE+/-0.5 D), 42 eyes myopic (SE <-0.5 to -6.75 D), and 8 eyes hyperopic (SE >+0.5 to +3.88 D). The corneal aberrations were derived from corneal topography (Keratron Scout, Optikon). The measurement of ocular aberrations was performed with a Tscherning wavefront aberrometer (ORK, Schwind). The aberrations of the Zernike coefficients and RMS values (1st to 4th order) were determined. RESULTS: The mean corneal and ocular Zernike coefficients of higher order were smaller than 0.2 microm. There was an evident decrease of wavefront aberrations with increasing order. Higher order corneal aberrations were larger than the corresponding ocular aberrations. With increasing age higher optical errors increased in complexity, and the correlation of corneal and ocular aberrations decreased with significant differences. Although the corneal ocular RMS value of the 3rd and 4th order correlated in the younger group (r=0.51, p=0.0001), there was no correlation in the older group (r=-0.48, p=0.832). The influence of age caused a significant increase of ocular aberrations of the 3rd and 4th order, in particular a tenfold extension of coma (C07) (p=0.002), a twofold extension of spherical aberration (C12) (p=0.0001), and an increase of the 3rd and 4th order RMS values (p=0.001). CONCLUSIONS: Increased age induced an increase in optical aberrations of the eye, which demonstrates the influence of the lens on ocular aberrations. The combination of corneal and ocular diagnostic methods is recommendable for a better understanding of visual performance.  相似文献   
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Zusammenfassung In der vorliegenden Untersuchung wurden 294 Nachkommen (5–34 Jahre) essentieller Hypertoniker bezüglich Blutdruck, Renin-Angiotensin-Aldosteron-System and anderer kardiovaskulärer Risikofaktoren wie Glukose, Cholesterin und Triglyzeride untersucht und mit 122 Nachkommen (5–34 Jahre) normotoner Eltern verglichen.Dabei zeigte sich, daß Nachkommen essentieller Hypertoniker im Mittel statistisch signifikant höhere systolische und diastolische Blutdruckwerte zeigten als solche normotoner Eltern (p<0,003 bzw. 0,005). Weiter ließ sich bei Kindern hypertoner Eltern im Mittel ein signifikant höheres Körpergewicht und ein größerer Body-Mass-Index beobachten als im Kontrollkollektiv (p<0,006 bzw. 0,001).Mit Ausnahme statistisch signifikant niedrigerer Ruhe-Plasma-Aldosteronwerte (p<0,002) bei Kindern essentieller Hypertoniker ließen sich zwischen beiden Kollektiven keine Unterschiede im Stimulationsaldosteron, in der Ruhe- und Stimulations-Plasma-Renin-Aktivität und im Plasmacortisol nachweisen.Ebenfalls zeigten die beiden Kollektive bezüglich der anderen untersuchten Parametern wie Kreatinin, Glukose, Cholesterin und Triglyzeride keine wesentlichen Unterschiede.Weiterhin wurden in der vorliegenden Untersuchung 41 hypertone Elternteile, 65 (normotone) Ehepartner von Hypertonikern und 47 (normotone) Eltern von Kontrollkindern untersucht. Erwarungsgemäß zeigten Hypertoniker statistisch signifikant höhere Blutdruckwerte als ihre Ehepartner und die Kontrolleltern (p<0,001). Interessanterweise zeigten die hypertonen Eltern nicht nur einen höheren Body-Mass-Index als Kontrolleltern sondeern auch als Ehepartner (p<0,01 bzw. <0,02). Diese Befunde stützen eine vorwiegend genetische Disposition als zugrundeliegende Ursache des höheren Körpergewichtsverhaltens und lassen eine vermehrte Nahrungsmittelaufnahme in Hypertonikerfamilien eher als unwahrscheinlich erscheinen.Die Ergebnisse der vorliegenden Studie legen es nahe, daß durch eine möglichst frühzeitige Kontrolle des Körpergewichtsverhaltens bei Nachkommen essentieller Hypertoniker ein Beitrag zur Primärprävention der Hochdruckkrankheit geleistet werden kann.Arbeit im Rahmen des Schweizerischen Nationalen Forschungs-Programmes 1B Prophylaxe der Herz- und Kreislauferkrankungen (Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung, Projekt Nr. 4.066.076.1)  相似文献   
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Over the past decades, echocardiography has undergone a continuous evolution in technology that has promoted its clinical application and acceptance throughout perioperative medicine. These technological advances include improvements in transducer development that permit superior imaging quality and a wider selection of probes for epicardial, epiaortic, and surface echocardiography which can also be used in conjunction with multiplane transesophageal echocardiography. Moreover, the addition of Doppler technology and digital acquisition has secured the role of echocardiography as a valuable and relatively noninvasive diagnostic tool for the assessment of cardiovascular disease and hemodynamic monitoring throughout the perioperative period. Therefore, it has become increasingly important for perioperative physicians to understand the basic principles and underlying fundamental concepts pertaining to the technology and physics of echocardiography, as well as its inherent limitations. The current review outlines the modes and applications of different echocardiographic techniques used in perioperative echocardiography including M-mode, two-dimensional echocardiography, and Doppler assessment of blood flow. In addition, the limitations of these techniques and typical artifacts associated with the perioperative use of echocardiography are described.  相似文献   
979.
The anaesthesiologist's competence in anaesthesia, intensive care medicine, pain therapy and emergency medicine is accepted throughout the medical society. Nevertheless, during the last decades patient surveys demonstrated a considerable lack of information of the responsibility of our work. By continuous education and information anaesthesiologists have aimed to improve the information and decision-making process for the patient. This multicentre trial was designed to investigate the current public view on our profession in seven German hospitals. In-hospital patients were asked to fill out a standardised questionnaire prior to the anaesthesia premedication visit and a total of 692 questionnaires (77%) were analysed. Results demonstrated an increased level of knowledge for anaesthesia (>95%), intensive care medicine (74%), and pain therapy (50% acute pain; 32% severe pain). In the case of emergency medicine (10%) the in-hospital and out-of-hospital responsibilities were not clear among patients. We conclude that the continuous distribution of information in recent years has contributed to improving patients' knowledge on interdisciplinary responsibilities. Future efforts should focus on the gaps in patient's knowledge to allow the patient to ask the right questions necessary for decision-making.  相似文献   
980.
Postoperative pulmonale Komplikationen   总被引:2,自引:0,他引:2  
Postoperative pulmonary complications are a major problem after upper abdominal or thoracoabdominal surgery. They lead to a prolonged ICU stay as well as increased costs and are one of the main causes of early postoperative mortality. Even after uncomplicated operations, postoperative hypoxemia occurs in 30-50% of patients. Acute respiratory failure involves a disturbance in gas exchange. The mortality ranges from 10 to 60% according to the severity of respiratory failure. The most important complications are interstitial and alveolar pulmonary edema, atelectasis, postoperative pneumonia, hypoventilation, and aspiration. Preoperative optimization, postoperative prophylaxis according to a stepwise approach, and early mobilization decrease the rate of complications.  相似文献   
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