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Biomedical subjects

H Haug

Publications and source records attributed to H Haug.

At least 91 records · Page 5Linked to original sources
PubMed1976

The postnatal development of myelinated nerve fibres in the visual cortex of the cat: a stereological and electron microscopical investigation.

With the aid of stereological procedures the development of myelinated nerve fibres (MF) was quantitatively investigated in electron micrographs of the visual cortex from animals of different ages: 36 days-old, the age at which fibres first appear, through adulthood. A short description of tissue treatment, methods and qualitative results is given. The following quantitative results are presented: 1. Myelinization begins at about the 36th day postpartum and is not completed by the 164th day. At this time a lack of about 20% MF can be observed. 2. The average diameter of MF decreases from 1.3 mum to 0.8 mum from day 36 to adulthood. 3. The first MF appear near the border of the album. 4. Beginning with the 55th day, small MF arise in layer I, showing two periods of growth. 5. The maximum MF density in the region of layer IV corresponds to the strip of Baillarger. Other aspects of visual cortex development are dealt with in the Discussion. The following conclusions can be drawn: a) The growing of in- and output-MF is completed first. b) The development of the internal connecting systems in layers I and IV begins a little later and is completed by the 5th month. c) The MF in layers II and III appear after the 4th month. Kaes (1907) has also described a continuation of MF growth in man lasting into the twenties.

Animals↗
PubMed1976

[The different procedures for value collection in biological morphometry and stereology (author's transl)].

Each stereological or morphometrical investigation presumes a high experience in structure diagnosis. Therefore, a good contrast between the structures to be evaluated is necessary, especially when using automatic measuring systems. Furthermore, some suggestions are given to facilitate the object-evaluation. The stereological principles including pattern-recognition are mentioned briefly in order to understand some of the technical details. The techniques are divided into simple and advanced procedures. However, it is also possible to evaluate using a simple counter combined off- or on-line with a computer. The advanced system can be divided into tracing instruments and photometric- and television-scanning procedures. The first system which is manipulated by eye-control can also be called "optomanual devices". These are planimetry, a type of automatic point counting, and instruments which locate the coordinates by ultrasound or a magnetic tableau. With relatively inexpensive electronics the coordinates can be transformed into stereological values. The photometric instruments and the television devices "Scan-computers" discriminate only between gray-steps while measuring. The first group works by moving either the photometric spot (flying spot) or the microscopical object-stage. The second group is guided by its computer and the output immediately shows the stereological results. The discussion gives information about choosing the best instrument for investigation. The scientist should keep in mind that the size of the over-all procedure, the frequency of measuring, the time of object preparation, the possible difficulty in discrimination of the gray-steps and the extent of his scientific funds are important for his decision.

Animals↗
PubMed1975

[The "juvenile" type of chronic myelogenous leukemia (author's transl)].

The juvenile type of chronic myelogenous leukemia (CML) is characterized by hemorrhagic diathesis, hepatosplenomegaly, generalized enlargement of lymph nodes, reduced erythro- and thrombopoiesis, leukemic infiltration of bone marrow, and decreased activity of leukocyte alkaline phosphatase. The disorder differs from the adult type by the early manifestation of anemia and thrombocytopenia, the minor degree of leucocytosis, the failure to demonstrate the Philadelphia chromosome, and the presence of fetal markers in the patients' erythrocytes. The persistence of fetal markers in erythrocytes and the clinical manifestation in infancy and early childhood suggest that the disease is congenital in origin. The occurrence of CML of the juvenile type in an 8-year-old boy, which is reported in this paper, favors a postnatal acquisition of the disorder. The significance of hematological and cytogenetic findings and new aspects of nosological classification are discussed.

Adolescent↗