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For signal transmission in traffic today, different optical, acoustic, or other physical or technical means are used for information. The different kinds of traffic (water navigation, road and rail, and, later air transport) made traffic regulation necessary early on. This regulation, from its very beginning in ancient times, began by means of optical signals; nowadays, this remains the most important method. From the very start, minimum requirements for the navigator's vision, color discrimination, dark adaptation, and even visual field were needed. For historical reasons, it was in seafaring medicine that these first developed. Besides the development of the different signals, methods for checking the requirements were soon developed. National and international requirements have been very different. Only within the last 50 years has international cooperation led to the acceptance of general standards for the different traffic modes.This article discusses the technical development of optical signals for the different kinds of traffic, from ancient times to the present, and explains the development of minimum requirements for the different visual functions.  相似文献   

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Zusammenfassung Es werden zwei Fälle von Lymphangiom der Orbita beschrieben. Die histologische Untersuchung und der Vergleich der beiden Geschwülste führt zu der Auffassung, daß das Vorhandensein des lymphatischen Gewebes in den Orbitalymphangiomen nicht kongenitalen Ursprungs ist, sondern sekundär entsteht und auf den Reiz zurückzuführen ist, welchen die Blutungen und das Fortschaffen des Blutes darstellen.  相似文献   

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Even though cataract surgery has been practised for over 2000 years, modern cataract surgery started just some 50 years ago.with the first IOL implantation by Sir Harold Ridley. The development of intraocular lenses was accompanied by great successes and disasters. With the fast development of cataract surgical techniques over the past 15 years (ECCE, Phacoemulsification, Capsulorhexis) a successful mariage between IOL-developments and surgery was established. Indication profiles for cataract surgery and IOL implantation extended to more and more patient groups. At this time classical cataract surgery is further developing into refractive intraocular lens surgery to correct higher ametropia in clear lens or phakic eyes. This development was only possible because of the improvements of surgical techniques and implants in classical cataract surgery.  相似文献   

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Ohne Zusammenfassung(Ein Auszug aus dieser Arbeit wurde in der Sitzung der ophthalmologischen Gesellschaft in Heidelberg am 28. September 1873 vorgelegt.)  相似文献   

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