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Biomedical subjects

H Bouma

Publications and source records attributed to H Bouma.

At least 19 recordsLinked to original sources
PubMed1982

Reading and the ophthalmologist. An introduction into the complex phenomenon of ordinary reading as a guideline for analysis and treatment of disabled readers.

Reading problems are a frequent source of complaint in ophthalmological practice. In many cases suitable optical correction is all that is needed. However, difficulties may remain despite adequate optical correction. This paper describes visual reading processes with the aim of making such difficulties understood and, if possible, providing remedies. Four different types of visual reading processes are distinguished: (a) optical imaging, (b)eye movement control, (c) visual word recognition and (d) integration of information across eye fixations. Next the attempt is made to use our insight to obtain a better understanding of actual reading problems, such as those of elderly readers, low-vision patients, and dyslexics as well as those of the blind. Therapeutic options, including visual aids are given due attention.

Accommodation, Ocular↗
PubMed1979

Writing apparatus controlled by head movements for motor handicapped people.

For a motor disabled person who cannot use his arms and hands we have constructed a device that enables him to operate a typewriter by means of head movements, via a forehead lamp. The text is first displayed on a picture screen and, after introducing any corrections, typed on a printer. This writing apparatus has been used very intensively for one year now, and evaluation laid down by the user himself has been included in the present paper. Several factors relevant to a large-scale application of this apparatus are discussed.

Journal Article↗
PubMed1975

Radioimmunological identification of polysomes synthesizing fibrinogen polypeptide chains.

Hepatocytes of rats stimulated by turpentine into a hyperfibrinogenemic state produce sufficient quantities of fibrinogen to permit unequivocal identification of specific polysomal complexes involved in the synthesis of this molecule. Monospecific antibodies directed against intact fibrinogen and one of its subunits, the gamma-chain, have shown two size classes of polysomes. Furthermore, it seems possible that polypeptide chain assembly may occur by having completed nascent chains bind to partially completed chains that are still attached to the polysome.

Animals↗
PubMed1975

Partial chemical characterization of rat fibrinogen.

Rat fibrinogen has been purified and compared with bovine and human fibrinogen with respect to a number of chemical characteristics, including molecular size, charge distribution, NH2-terminal amino acids, total amino acid composition, and interspecies immunological cross-reactivity. Although human and bovine fibrinogen demonstrated three nonidentical polypeptide chains by sodium dodecyl sulfate gel separations and by CM-cellulose separations, rat fibrinogen Aalpha and Bbeta chains exhibited identical molecular weight sizes as well as identical charges. The presence of two nonidentical chains in these preparations was shown by qualitative NH2-terminal sequence analyses. The gamma chain of rat fibrinogen was also shown to be quite distinct from the gamma chains of human and bovine fibrinogen in its elevated content of cysteinyl and methionyl residues. Rat fibrinogen possesses the first reported blocked gamma chain NH2-terminal amino acid of any species. It is concluded that, although many chemical properties of rat fibrinogen are unique, the basic molecular structure has remained consistent when compared with that of fibrinogen from the vertebrates studied thus far. Moreover, the inducibility of this system, together with the partial chemical characterization of the fibrinogen molecule, provides important information for the use of rat fibrinogen as a model system in studying the biosynthesis and assembly of this complex molecule.

Amino Acid Sequence↗