M. Vogel – författare

References ............................................... 59 Subject Index ............................................. 65 6 Introduction The retina as an organ of perception of light, colour, shape and movement has been the subject of numerous and intensive light- and electron-microscopical investigations. To date the interest in these has largely been concentrated on the structure of the ma­ ture retina and the genesis of its cellular elements. The first exhaustive observations on the development of the retina in vertebrates were made by Babuchin (1863). Using the retinae of chicken embryos, he showed that Millier's radial fibres and the ganglion cells are the first to develop, while the receptor segments are the last. Subsequently, the early differentiation of Millier's radial fibres was often reaffirmed (Cajal, 1893; Meller, 1968; Bhattacharjee and Sanyal, 1975; and others). Furthermore, Babuchin had already indicated that the structural development in the area of the posterior pole is very rapid compared with those regions of the retina which are situated more peripherally. Today, when comparing results of electron-mi­ croscopical investigations, this fact is of particular importance, since in each case only very limited areas of the retina can be examined. Schultze (1867a, b) pointed out the uniformity of origin and the general classifica­ tion of light-perceiving elements into inner and outer segments, thus contesting the hitherto generally held opinion that these structures, like the pigment epithelium, ori­ of the eye cup. In 1881 Ogneff discovered the analogous ginate from the outer leaf mode of formation in birds and mammals.

Leider war es nicht möglich, den zweiten Band unmittelbar im Anschluß an den ersten herauszubringen. Dies hat zwar den Vorteil, daß eine Reihe neuer Erkenntnisse aufgenommen werden konnte; andererseits hat sich aber wiederum deutlich gezeigt, daß in der so kurzen Zeit von zwei Jahren manches Problem aktuell wird, das im ersten Band nur angedeutet oder kurz behandelt werden konnte, das aber die Arbeit der nächsten Zukunft voraussichtlich bestimmen wird. Um nur einiges herauszugreifen: Für die Genese des juvenilen Diabetes wird die Infektion mit dem Coxsackie­ Virus nicht mehr in Betracht gezogen. Dagegen hat sich unbezweifelbar zeigen lassen, daß die Erzeugung eines Diabetes im Tierversuch durch Virusinfektion an immunopathologische Vorgänge und genetische Faktoren geknüpft ist. Die Genese des menschlichen, akut entstehenden Insulinmangel-Diabetes auf immu­ nologischer plus hereditärer Basis wird weiterhin in der Diskussion bleiben. Pathogenetische Erkenntnisse sind zu erhoffen. In Zusammenhang damit steht die genetische Verbindung der Insulin-Antikörperproduktion bei insulinbedürf­ tigen Diabetikern mit Histokompatibilitäts-(HL-A)-Antigenen, die das Diabetes­ risiko erhöhen, andererseits aber Schutzfunktionen für die Diabetesentstehung signalisieren können. Ein weiteres Problem, dem sich die wissenschaftliche Arbeit in naher Zukunft mit Sicherheit widmen wird, ist die Frage nach der Bedeutung des Somatostatin und der D-Zelle im Inselsystem, in der dieses produziert wird. Hier wird sich die Frage der Sicherung der von OReI und UNGER entwickelten Hypothese der Insel als eines multihormonellen Mikroorganismus stellen, in dem nebeneinander Insulin, Glukagon und Somatostatin gebildet werden und gegenseitige regulato­ rische Funktionen ausüben.

References ............................................... 59 Subject Index ............................................. 65 6 Introduction The retina as an organ of perception of light, colour, shape and movement has been the subject of numerous and intensive light- and electron-microscopical investigations. To date the interest in these has largely been concentrated on the structure of the ma­ ture retina and the genesis of its cellular elements. The first exhaustive observations on the development of the retina in vertebrates were made by Babuchin (1863). Using the retinae of chicken embryos, he showed that Millier''s radial fibres and the ganglion cells are the first to develop, while the receptor segments are the last. Subsequently, the early differentiation of Millier''s radial fibres was often reaffirmed (Cajal, 1893; Meller, 1968; Bhattacharjee and Sanyal, 1975; and others). Furthermore, Babuchin had already indicated that the structural development in the area of the posterior pole is very rapid compared with those regions of the retina which are situated more peripherally. Today, when comparing results of electron-mi­ croscopical investigations, this fact is of particular importance, since in each case only very limited areas of the retina can be examined. Schultze (1867a, b) pointed out the uniformity of origin and the general classifica­ tion of light-perceiving elements into inner and outer segments, thus contesting the hitherto generally held opinion that these structures, like the pigment epithelium, ori­ of the eye cup. In 1881 Ogneff discovered the analogous ginate from the outer leaf mode of formation in birds and mammals.

The international symposium on transposition of the great arteries was held in Munich on May 3-5, 1991. It was organized by the German Heart Center Muni eh with two aims: firstly, to commemorate the 25th anniversary of Dr. Rashkind's publication: "Creation of an atrial septal defect without thoracotomy" (which appeared in 1966 in the Journal of the American Medical Association), and to honor this great pediatric cardiologist, who was one the pioneers of interventional catheterization. secondly, to give an overview of current medical knowledge about the pre- and postnatal diagnosis, medical and surgical treatment, and postoperative evalua- tion of transposition of the great arteries. Fig. 1. Dr. Rashkind in his Iabaratory checking his balloon catheter V This symposium brought tagether embryologists, morphologists, experts in fetal cardiology, pediatric cardiologists, and pediatric cardiac surgeons from 10 different countries. Thus, we were able to describe the current state-of-the-art of pre- and postnatal management and the surgical treatment of this second most common con- genital cyanotic anomaly of the heart. Dr.Rashkind's approach to create an atrial septal defect in the setting of com- plete transposition of the great arteries dramatically changed the natural history of this cyanotic heart defect, which carried a 90% neonatal mortality before this effec- tive palliation became available.