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Many women of childbearing age now work in an environment that is associated with reproductive and teratogenic risks. Problems relating to the assessment and control of potential teratogenic hazards in the work place are discussed in this paper. Risk factors include industrial solvents, air pollution, water pollution, noise, anesthetic agents, and video display terminals.

The kinematicaly open, dimeric link chain represents the simpliest module of a diarthrosis. The simpliest synarthrosis is represented by a (visco-)elastic disk that connects two rigid bodies. Diarthroses and synarthroses are statically distinguished by the character of force transfer. Because of their adhesive connection to the corresponding bony structures synarthroses can transfer shear stresses while diarthroses can only be loaded by forces which act normal to their functional surfaces. Therefore, the interface between the body structure and the elastic synarthrosis can be considered as a surface of infinite static (adhesive) friction, while the contacting surfaces in a diathrosis possess vanishing static friction. Kinematically, the difference between diarthroses and synarthroses is established by the fact that diarthroses possess axes of rotation which are approximately fixed relatively to the morphology of the corresponding functional surfaces while in synarthroses the positions of rotational axes depend on the geometric structure of the applied and transferred force system. The first part entire paper presents the most simple module of a diarthrosis, the kinematically open dimeric link chain.

The Semmelweis-Museum in Budapest, Hungary, has a small collection of anatomical wax models. Studying the correspondence of the Austrian emperor Joseph II., then King of Hungary with representatives of the Hungarian administration, we were able to find out the origin of these models, their transportation to Hungary and their large significance in anatomical teaching at the end of the 18th century in Hungary. These models are the result of a long-lasting cooperation between artists and anatomists, particularly in Italy. Their artistic climax is reached during the second term of the 18th century, reflecting the complex interaction of contemporary sociocultural trends i.e. popularization of results of scientific research, traits of enlightenment combined with an artistic hyperidealistic typization as known from classical antiquity and sponsored financially as a means of imperial representation. The aim of the study was to point to the eminent importance of this collection as a monument of cultural heritage.

The studies were performed on 103 samples of human fetal pancreas tissue (10th to 26th week of gestation). Of the mothers, 14 had insulin dependent type I diabetes mellitus (IDDM), and 33 of the samples were examined before and after cultivation for 14 days. 3 samples taken from fetuses in the 14th week of development (mothers without metabolic disorders) were examined in the electron microscope. Lymphocytes are generally irregularly distributed within the tissue. Groups of 3 to 5 lymphocytes are found in addition in the 12th week of development, and larger clusters (10 to 15 lymphocytes) appear from the 14th week onward. Relating these quantitative results to the 3 phases of early fetal islet organ development, it can be seen that lymphocyte numbers increase from the 10th to the 26th week of development. The significance of this is discussed in connection with the development of the immune system. In view of the contemplated transplantation of fetal pancreas tissue as treatment for IDDM, it means that a relatively low immunogenicity can be expected up to the 14th week of development. Thymic differentiation is not complete before the 17th week, and differentiation of the lymph nodes and spleen continues until weeks 20 to 23. Although IgG antibodies are transferred across the placental barrier already in about the 8th week, this flux does not reach its maximum until the 32nd week. Endogenous antibody synthesis in the fetus does not start until the 18th week. IDDM of the mother during fetal development (10th to 26th week) does not increase the lymphocyte number in the pancreas. This also applies to tissue that has been cultivated for 14 days after reaching the same stage of development.

The interindividual comparison of guiding contours on the base of incisors and molars shows a relation of protrusive incisal and molar contours. In practical application when no sagittal incisal curvature is obtainable the extraction from the molar region is to be valued as the first correct step to determine the individual constant "a". This allows the individual, biomechanically required reconstruction of the frontal vault of guidance.

The Haversian canal system in the diaphysial compacta of the femur in 4 mammalian species (dog, pig, bovine, horse) was studied on the decalcified bone using a method developed by the authors. In the microscopic studies we found that in all species the network aspects vary with the depth of the compacta layer. In all layers, there is a background of longitudinal canals with more or less regular trajectories describing large curves. The anastomoses linking them are main elements that define the variety of the network aspects both from layer to layer and from species to species. The canal densities vary between broad limits in the dog and horse, but less in the pig and bovine. The mean density decreases in the following order of species: dog, pig, horse and bovine femur. The Haversian canal diameter varies within narrow limits in the dog and pig. The limits are broader in the horse and bovine. The mean diameter diminishes in the following order of species: bovine, dog, horse, pig. We can conclude that the canal network differs from one species to another from all points of view: the canal system is homogeneous in none of these parameters.

The internal structure of mitochondria with prismatic cristae in astrocytes of the inferior olivary nucleus of the adult cat was examined. The interior of the mitochondria with prismatic cristae cut in cross-section can be divided into 2 areas: (1) a peripheral, rather structureless area, and (2) a central, highly organized area. The former is composed of the inner mitochondrial membrane and a small number of peripheral cristae protruding from the membrane and scattered dots. The latter is composed of numerous prismatic cristae arranged in almost hexagonal spacing and many dots which probably represent the transverse configuration of filaments oriented parallel to the cristae embedded in the matrix. For future comparative analysis, various quantitative observations on the fine structure of the central, highly organized area are described and discussed.

The number of muscle fibres per mm2 is age dependent, and therefore briefly denoted as age specific number (Alterskennzahl AK). We determined the AKs for the age groups up to 25 years, separated after the sexes and for M. vastus lateralis et deltoideus. According to the trend of the original data the approximations have been carried out applying 4 functions of organismic growth in modified form, i.e. the Pütter (1920), Bertalanffy (1934), Richards (1959), Janoschek extended by Sager (1984) and Richards extended after Sager (1980). Curve fitting is reached by regression analysis and nonlinear regressions using the sums of the linear deviations as a criterion for the goodness of fit. Results including initial as well as final values are summarized in tables with the parameters of the calculation methods added. The AKs allow judging the degree of maturity in the skeletal musculature during childhood. Transposing of the equations for AK = W yields t as a function of the normally adjunctive age specific number. The difference against real age reveals to which degree the musculature is eventually underdeveloped. Concerning the interpretation the fact should be kept in mind that biological processes are involved. The relation of the fibre types too implies a characteristic age dependency. This statement and the fibre diameters gained from the same material allow a mutual control and an exact fixation in each case.

The protrusive cranial border movement of the human mandibula is--structurally considered--identical to that of a couple in a cam gear. This mechanism can approximately be replaced by a link quadrangle and mapped by a standard gear. Other mammaliae use the same principle. They show surprising features of construction.

In the epithelium of the fetal bovine large intestine there are endocrine cells, predominantly at the base of the crypts. According to morphological characteristics, EC-cells and L-cells can be readily distinguished.