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Biomedical subjects

L Nelson

Publications and source records attributed to L Nelson.

At least 181 records · Page 10Linked to original sources
PubMed1979

Intranuclear inclusion bodies in epithelial cells of human vas deferens.

Four different types of inclusion bodies were seen within the nucleus of the principal cells in segments of vas deferens from 40 fertile males: (1) electron-dense homogeneous bodies of various sizes (0.1--1.8 microns) and shapes, (2) granular bodies approximately 0.06--0.12 microns, (3) lipid inclusion bodies, and (4) less electron-dense, filamentous bodies. They were either membrane-bound or free within the nucleoplasm. Some membranous material was scattered within the nucleoplasm. The internal structure of nuclei containing these bodies differed from cell to cell. The nucleoplasm was composed either of dense granular elements or fine filamentous components. The aggregation and density of the ground nuclear material increased with increasing numbers of inclusion bodies. Very dense nuclei were in cells with typical features of degeneration. Frequently, extruded parts of cells or entire cells were seen within the lumen of the vas deferens.

Adult↗
PubMed1978

The 75 S RNA transcription unit in Balbiani ring 2 and its relation to chromosome structure.

A defined transcription unit in the Balbiani ring 2 (BR 2) region of chromosome IV in the salivary glands of Chironomus tentans has been characterized on the basis of analysis of the corresponding primary transcript, 75S RNA, and its functional significance. The available information on the transcription unit and its relations to chromosome structure can be summarized in the following way: 1. The size of the 75S RNA transcription unit in BR 2 is on the order of 30 000 base pairs. 2. The unit is likely to contain a long coding segment (at least 6000 base pairs), probably corresponding to information for salivary polypeptides. 3. The sequences are distributed in more than one chromomere (probably in 3--5 chromomeres). Further studies are needed before it can be stated whether or not there is a simple one-to-one relation between chromomeres and transcription units in the BR 2 region.

Animals↗
PubMed1977

The effect of the synthetic prostaglandin analog 15 (R) 15 methyl-PGE2 methyl ester on gastric mucosal hemorrhage induced in rats by taurocholic acid and hydrochloric acid.

The incidence of mucosal hemorrhage induced in rats by the oral administration of taurocholic acid (TCA) and hydrochloric acid (HCl) both singly and in combination was investigated. The effect of prostaglandin 15 (R) 15 methyl-PGE2 methyl ester (Me-PGE2) on the occurrence of hemorrhage induced by TCA with HCl was also studied. The incidence of hemorrhage induced by TCA (10 mM) alone and HCl (160 mM) alone was minimal and not different from that induced by the control solution. The combination of TCA (10 mM) and HCl (160 mM) produced bleeding in 67.7% of animals. The addition of 15 (R) 15 methyl-PGE2 methyl ester (9.9 micronM, corresponding to 50 microng/Kg) significantly reduced the incidence of hemorrhage induced by the combination of TCA with HCl from 67.7% to 31.3%. This suggests that this synthetic prostaglandin may be of value in conditions thought to be associated with reflux of bile into the stomach.

Animals↗
PubMed1976

Basal lamina of human seminiferous tubule- its role in material transport. I. In presence of tunica vaginal hydrocele.

Electron microscopy of testicular biopsies obtained from two adult males with tunica vaginal hydrocele revealed some protrusions from the basal lamina to the germinal epithelium in the seminiferous tubule. The protrusions were of three types: some between the spermatogonia and Sertoli cells, some directly within the Sertoli cell cytoplasm and others inside the spermatogonia. The protrusions inside the spermatogonia were only 0.5 mum deep whereas the other types were from 1-11 mum deep. Occasionally some cut off portions of these protrusions were seen inside the ground cytoplasm of the Sertoli cell without an apparent connection with the original stalk. The matrix of the protrusions contained a homogenous component (composed of a fine filamentous element) and granular and membranous components. These components closely resemble the materials found in the basal lamina of the seminiferous tubule. It has been suggested that under mild pathological conditions, i.e., hydrocele, the junctions between the seminiferous tubule epithelium and the basal lamina become somewhat more flexible. As a result, the protrusions become longer and a passage might be formed to allow the flow of raw materials in or out of the seminiferous tubule.

Adult↗
PubMed1976

Effect of prostaglandin 15(R) 15 methyl-E2 methyl ester on aspirin and taurocholic acid-induced gastric mucosal haemorrhage in rats.

The effect of orally administered prostaglandin 15(R)15 methyl-E2 methyl ester on aspirin and taurocholic acid-induced gastric mucosal haemorrhage has been studied in rats. The incidence of haemorrhage induced by aspirin (26-7 mM), 64 mg/kg, together with taurocholic acid (2-5 mM), was significantly reduced from 53-6% to 19-5% by the addition of the prostaglandin (9-9 muM), P less than 0.01. The incidence of haemorrhage induced by aspirin alone (53-3 mM), 128 mg/kg, was significantly reduced from 80% to 20% by the addition of prostaglandin (9-9 muM), P less than 0.002. These results indicate the possible use of synthetic prostaglandins in the prevention of aspirin-induced gastric pathology.

Animals↗