Biomedical subjects

S Walsh

Publications and source records attributed to S Walsh.

At least 163 records · Page 9Linked to original sources

PubMed1979

The identification of urogastrone in serum, saliva, and gastric juice.

Urogastrone, a peptide isolated from human urine, is known to cause inhibition of gastric acid secretion and proliferation of fibroblasts in culture; furthermore immunofluorescent localization techniques show it to be present in submandibular and Brunner's glands. Serum, saliva, and gastric juice samples have now been fractionated upon Sephadex G-200 and G-50 and the immunoreactive urogastrone located using a specific radioimmunoassay. Biologic activity was shown by mitogenic studies with 3T6 fibroblasts. In serum, the major immunoreactive component was ca. 1-2 X 10(5) daltons, but trypsin treatment then gave a smaller biologically active species in the same position as pure urogastrone on Sephadex G-50. Both saliva and gastric juice showed major components at the position defined by urogastrone, and these also stimulated the uptake of [H]thymidine into the fibroblasts. It is concluded that a urogastrone-like molecule can be released enzymically from a high molecular weight serum precursor and that the small biologically active peptide is also a normal component of saliva and gastric juice.

Autoradiography↗

PubMed1978

The eyes of mesopelagic crustaceans. III. Thysanopoda tricuspidata (Euphausiacea).

The compound eyes of the mesopelagic eupausiid Thysanopoda tricuspidata were investigated by light-, scanning-, and transmission electron microscopy. The eyes are spherical and have a diameter that corresponds to 1/6 of the carapace length. The hexagonal facets have strongly curved outer surfaces. Although there are four crystalline cone cells, only two participate in the formation of the cone, which is 90-120 micrometer long and appears to have a radial gradient of refractive index. The clear zone, separating dioptric structures and retinula, is only 90-120 micrometer wide. In it lie the very large oval nuclei of the seven retinula cells. Directly in front of the 70 micrometer long and 15 micrometer thick rhabdom a lens-like structure of 12 micrometer diameter is developed. This structure, known in only a very few arthropods, seems to be present in all species of Euphausiacea studied to date. It is believed that the rhabdom lens improves near-field vision and absolute light sensitivity. Rod-shaped pigment grains and mitochondria of the tubular type are found in the plasma of retinula cells. The position of the proximal screening pigment as well as the microvillar organization in the rhabdom are indicative of light-adapted material. The orthogonal alignment of rhabdovilli suggests polarization sensitivity. Behind each rabdom there is a cup-shaped homogenous structure of unknown, but possibly optical function. Finally, the structure and the function of the euphysiid eye are reviewed and the functional implications of individual components are discussed.

Biological Evolution↗

PubMed1978

Assessing the validity of EMS data.

Variation in the assessment of basic clinical data gathered by emergency medical technicians and emergency department nurses was studied. Prior to testing, precise definitions, categories and procedures were developed and tolerance limits for the quantitative variables were created. Each participant evaluated four consecutive patients simultaneously with another evaluator setting the standard. The results indicate that the error rate is low to moderate for the different variables. For the quantitative variables, the error rate is over 20% and, when an error does occur, it is often very large. This indicates a need for ongoing emphasis on accurate measurement and, in cases where highly accurate data is essential, the use of multiple observers.

Data Collection↗

PubMed1977

The eyes of mesopelagic crustaceans: I. Gennadas sp. (penaeidae).

The eye of the deep-sea penaeid shrimp Gennadas consists of approximately 700 square ommatidia with a side length of 15 micrometer. It is hemispherical in shape and is located at the end of a 1.5 mm long eye stalk. The cornea is extremely thin, but the crystalline cone is well-developed. A clear zone between dioptric structures and the rhabdom layer is absent. A few pigment granules are found within the basement membrane; otherwise they, too, are absent from the eye of Gennadas. The rhabdom is massive and occupies 50% of the eye. It consists of orthogonally oriented microvilli (the latter measuring 0.07 micrometer in diameter) and is 75 micrometer long. In cross sections adjacent rhabdoms, all approximately 8 micrometer in diameter, form an almost continuous sheet and leave little space for retinula cell cytoplasm. In spite of a one h exposure to light, rhabdom microvilli show no disintegration or disruption of membranes. Vesicles of various kinds, however, are present in all seven retinula cells near the basement membrane. Bundles of seven axons penetrate the basement membrane. On their way to the lamina they often combine and form larger aggregations.

Animals↗

PubMed1976

Meet the British.

Explore the source record for details and available documents.

Acculturation↗

PubMed1976

Chequerboard pattern reversal using a modified television display to measure visual evoked responses.

The clinical value of visual evoked response measurement is noted with particular reference to the stimulus source used. The complexities of response to brief flashes of light has led to the increased use of chequerboard reversal as a stimulus source. Thus far, the chequerboard reversal has been produced by opto-mechanical means. This paper presents the results of using a television display as the stimulus generator, and some of the advantages of such a purely electronic source of pattern reversal are discussed.

Data Display↗

PubMed1975

Technetium-99m-diphosphonate accumulation in amyloid.

A well-documented case of multiple myeloma complicated by histologically demonstrable amyloidosis is presented. Technetium-99m-diphosphonate in the areas of amyloid deposition about the shoulders and hips is shown. This adds another dimension to the extraosseous sites without demonstrable calcification where accumulation of bone-seeking radiopharmaceutical can be observed. In patients where symmetrical uptake of such agents is noted in the periarticular soft tissue, particularly of the hips and shoulders, amyloidosis must become a diagnostic consideration. This is particularly true in patients presenting with undiagnosed arthralgia.

Amyloidosis↗

PubMed1973