McGill University Thèses et mémoires publiés en 1971

The renewal of various types of epithelial cells was examined in the descending colon of adult mice given 3H-thymidine. Semi-thin Epon sections were stained with PA-Schiff-iron-hematoxylin and radioautographed. The existence of three cell lines was established: vacuolated columnar, mucous and enterochromaffin. In the vacuolated-columnar cell line, only vacuolated cells divide. A vacuolated cell at the cryptal base and its progeny would go through three mitotic cycles in the lower two-thirds of the crypt before becoming columnar cells. In the mucous cell line, cells originate from vacuolated cells in the lower one-third of the crypt and undergo one or two mitotic …  Lire la suite

Temporal masking effects of a 50 msec noise-burst on the perception of three voiceless stop consonants in CV syllables, /pa/, /ta/, /ka/, /pu/, /tu/, and /ku/, were investigated. Temporal relations between the noise and syllable ranging between 600 msec before to 150 msec within the syllable, and six different noise spectra, comprising one wide-band and five octave-bands, were used. Two noise sound pressure levels, 88 dB and 96 dB, and six syllable levels, comprising seven S/N ratios between -22 dB and -50 dB were investigated. Listening tests were conducted on two groups of ten subjects with normal hearing. Results demonstrated …  Lire la suite

In the present work, experimental data is obtained for the amount of air entrained by water and sugar solutions, of viscosities 3.6 and 4.7 centipoises, flowing down pipes of diameters 1.0, 1.5 and 2.0 inches. The dynamics of vapour entraining flow is discussed, and a method for calculating liquid flow rate at which pipe flows full is suggested. The experimental results have been presented in terms of some of the common dimensionless groups used in fluid mechanics in an attempt to develop an overall correlation scheme.  Lire la suite

Neurophysin is a generic term for neurohypophysial proteins that bind vasopressin and oxytocin. A radioimmunoassay for neurophysin has been developed, and also used for immunological studies of different components of neurophysin. A new component of norcine neurophysin, designated peptide IV, has been isloated, which is similar to the porcine neurophysin standard, peptide II, in amino acid composition, molecular weight and immunological reactivity, but different in electrophoretic mobility. The concentration of neurophysin increases progressively from the hypothalamus along the pituitary stalk to the posterior lobe. Different components of neurophysin in one or between species differ slightly in molecular weight, but vary …  Lire la suite

The nature of the association between pulmonary atherosclerosis and pulmonary hypertension was investigated by inducing les ions ln the pulmonary arteries of rabbits and examining the material for evidence of a coincident pulmonary hypertension. Two techniques were used to induce the lesions, one mechanical and the other dietary. In the first, the lung was embolized with segments of polyethylene tubing in a feasibility study whose purpose was to induce fibrin-platelet thrombosis. In the second, lesions were induced by cholesterol feeding and, in a sub-group, modified by the administration of synthetic surface-active agents.  Lire la suite

In a series of experiments, the role of so called "Intestinal factor" in low flow states was studied. The intestinal mucosa tolerated high flow cardiac bypass well, although non-pulsatile blood flow reduced mucosal perfusion and increased vascular resistance. However. the intestinal mucosa was highly vulnerable to excessive hemodilution, low cardiac output and shock. Sequential histological study revealed progressive lifting of the mucosal epithelium, and the pace of the damage was found to be flow-dependent. Correlation with the results of metabolic study indicated that such epithelial lifting might constitute a transport barrier at the epithelial-capillary interface. Supplying an energy substrate (glucose) …  Lire la suite

Incorporation of intravenously administered palmitic acid 9,10^3H into beta-lipoprotein steadily increases for the first 20 hours of hepatic regeneration. Thirteen hours after partial hepatectomy the concentration of circulating beta-lipoprotein is at a normal level, but the specific activities of liver and beta-lipoprotein-triglyceride were significantly diminished. During perfusion the 13 hour regenerating liver secretes quantities of beta-lipoprotein-triglyceride which exceed those released by a zero hour liver although there is no difference in liver weight. Equal quantities of protein were released by both livers. Triglyceride specific activity in the liver and perfusate B-lipoprotein was diminished, but the protein was not affected. Prelabelling …  Lire la suite

Le Chercheur de tresors ou L'Infiuence d'un livre, qu'historiquement on a defini comme le premier roman canadienfran~ais, a toujours ete meconnu par la critique dtici. Nous tenterons par une analyse fonctionnelle, de mettre en relief les traits dominants de la structure du recit, autant comme "histoire" que comme "discours" (selon les termes empruntes a Tzvetan Todorov) [...]  Lire la suite

Plasma converting enzyme activity (PCEA) and plasma renin activity (PRA) were measured simultaneously by the Boucher's methods. PCEA was similar in 13 control subjects and 33 essential hypertensive patients on 135 mEq Na and 90 mEq K diet in recumbent position. The renin-stimuli upright posture, furosemide, and sodium depletion did not modify PCEA in control subjects and essential hypertension, while PRA increased (p < 0.01) in all control subjects and essential hypertension but 7 patients with suppressed renin. We found a slight decrease of PCEA with pressor doses of angiotensin II or nor-epinephrine in normal subjects on sodium depletion.  Lire la suite

From 1925 till his death, Abd al-Hamid ibn Badis, an Algerian who trained in the traditional Islamic sciences, set to reconstruct his society from the decadent state in which traditionalism and colonialism plunged it into to one in which Islamic principles and Modernism could be reconciled.  Lire la suite