The elimination and retention of a new, fully synthetic plasma prosthesis of Czechoslovak origin under the working name of Duxon (poly[N-(2-hydroxypropyl)methacrylamide]) was investigated in experiments on rabbits by using a 14C-labeled polymer. Results published earlier on elimination have been confirmed and extended. Retention was examined after repeated application. The effect of molecular weight prevailed both in elimination and in retention. Polymers of lower molecular weights, which possess a good therapeutical effect, are not permanently deposited in the organism.

The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.Product liability: The publishers cannot guarantee the accuracy of any information about dosage and application contained in this book. In every individual case the user must check such information by consulting the relevant literature.

Four specimens with an aberrant sex chromosome constitution were found in natural populations of the common vole (Microtus arvalis). Two females had an X0 sex chromosome constitution and single males were 2n = 47, XXY and 2n = 47, XYY, respectively. No apparent phenotypical anomalies were recorded in the sex chromosome aneuploids, but their fertility may have been impaired. The incidence of sex chromosome aneuploidy seems to be unusually high in natural populations of the common vole (1.5% of animals examined). Possible explanations for this are discussed.

S tiS r b a 0.: Staging and Ageing of Mammalian Embryos and Fetuses. Acta vet. Hmo, 1995,64: 83-89.The objective of this study was to elaborate a method of estimating the age of embryos and fetuses of mammals of unknown ontogenetic age, applicable to both altricial and precocial mammals showing different duration of intrauterine development. The method consists of two steps: First, the embryo or fetus under study has to be "staged". It is measured, weighed and classified according to the characteristics given below, in one of the 13 comparable ontogenetic stages. The second step is "ageing": the staged embryo is placed in a point on the regression curve of the respective developmental stage that corresponds to the·duration of intrauterine development. The characteristics of the comparable developmental stages, the regression curves and the way in which they are calculated are presented. This method makes it possible to estimate the age of mammalian embryos and fetuses of unknown ontogenetic age, even of those already sectioned in histological series. In this way it is also possible to estimate the rates of morphogenetic events, the growth rate of the whole embryo or of its individual parts and/or organs.

The present study deals with the period of cooperation between Prof. Dr. Jan Kolda and Doc.Dr. Jan Hold and their pupils during which they elaborated standard methods of the cutting of meat based on anatomy. Another subject of cooperation were studies on the morphology of skin and hides under various methods of processing. The cooperation ended when first Doc. Hold died prematurely and then Professor Kolda. The situation of that time prevented any of this kind of research to be continued.