scispace - formally typeset
Search or ask a question

Showing papers by "Université de Sherbrooke published in 1975"


Journal ArticleDOI
TL;DR: The frequency of congenital hypothyroidism is about one in 7,000 births and the immunoassay is effective in detecting thyroid hormone abnormalities with an acceptable percentage of false positive measurements; no false negative results have occurred.

319 citations


Journal ArticleDOI
TL;DR: In this paper, a new stereoelectronic theory for the cleavage of the tetrahedral intermediate in the hydrolysis of esters and amides is presented, based on the orientation of the lone pair orbitals of the hetero-atoms.

197 citations


Book
01 Jan 1975

123 citations


Journal ArticleDOI
TL;DR: The sites of luteinizing hormone-releasing hormone (LH-RH) neurons and their axonal pathways in the hypothalami of rats and mice were studied by the immuno-globulin-peroxidase bridge technique and the immunofluorescent isothiocyanate technique, using rabbit antiserum to synthetic LH-RH.
Abstract: The sites of luteinizing hormone-releasing hormone (LH-RH) neurons and their axonal pathways in the hypothalami of rats and mice were studied by the immuno-globulin-peroxidase bridge technique and by the immunofluorescent isothiocyanate technique, using rabbit antiserum to synthetic LH-RH. Both of these techniques give similar results concerning LH-RH localization both in rats and mice. The immunoreactive LH-RH positive neurons are about 18–26 μ in diameter, mostly angular, pyriform or spindle shaped and very rarely oval or round. Most of these neurons are generally scattered in the hypothalamus. In the preoptic and medial prechiasmatic areas, ventromedial, arcuate nuclei and ventro-lateral-premammillary body, the neurons are numerous and mostly in groups of 3–6. In other areas of the hypothalamus surrounding the suprachiasmatic area, supraoptic area, paraventricular nuclei and the anterior hypothalamic area, the LH-RH neurons are few and scattered. Very few neurons occur in the median eminence or in the infundibular stem. Major projections of LH-RH neurons apparently originate from preoptic, prechiasmatic and surrounding suprachiasmatic area, and from the anterior hypothalamic area. The fibres run in the fibrillar zone, descend in the external infundibular zone, and finally terminate for the most part around the capillaries of the primary portal plexus of the hypophysis. Other major groups of fibres apparently originate from the arcuate and ventromedial neurons. These fibres bend above the fibrous zone for some distance, ultimately descending in the zona palisadica and zona granulosa of the median eminence, towards the capillaries. The fibres of the ventrolateral-premammillary neurons are seen on the floor of the premammillary recess of 3rd ventricle and apparently terminate close to the capillaries in the infundibular region. Most of the LH-RH nerve fibres terminate near the primary portal plexus of the hypophysis, while some terminate in the pars tuberalis and a few seem to terminate in the 3rd ventricle. The LH-RH antiserum is ineffective after absorption with the antigen, so the staining reaction appears to be specific for LH-RH.

94 citations


Journal ArticleDOI
01 Oct 1975-BJUI
TL;DR: Uroflowmetry proved to bring objective evidence of the degree of obstruction with a reasonable degree of accuracy and maximum urinary flow appears to be more accurate than other flow parameters in the determination of lower urinary tract obstruction.
Abstract: A group of 173 prostatic patients were submitted to a prospective study to determine the respective value of symptoms, uroflowmetry, endoscopic and radiological findings in the assessment of the degree of urinary obstruction. Uroflowmetry proved to bring objective evidence of the degree of obstruction with a reasonable degree of accuracy. Maximum urinary flow appears to be more accurate than other flow parameters in the determination of lower urinary tract obstruction.

71 citations


Journal ArticleDOI
01 May 1975-Urology
TL;DR: Strict specifications are proposed to be utilized for such a procedure, using a catheter with eight side holes measureing 0.34 mm to standardize the pressure profile measurement.

70 citations


Journal ArticleDOI
TL;DR: It was concluded that the LH-RH is packaged or condensed into granules in the Golgi cisternae.
Abstract: Luteinizing hormone-releasing hormone (LH-RH) was localized in neurons of the arcuate nucleus and median eminence, and in many of the nerve fibres of the median eminence of the rat, by using antisera to synthetic LH-RH with the immunoglobulin-peroxidase technique or by using a soluble peroxidase-antiperoxidase complex at the electron microscopic level. Many of the arcuate neurons and some of the median eminence neurons contained numerous densely stained granules (diameter about 90–130 nm) associated with the Golgi complex, and scattered granules elsewhere in the cytoplasm. Similar granules, positive for LH-RH, were observed in many nerve profiles around the capillaries of the primary portal plexus of zona palisadica and zona granulosa of the median eminence, and such profiles may represent the release sites of LH-RH into the portal vessels. About 20% of the nerve profiles around the primary portal plexus were LH-RH positive and the rest of the nerve profiles were negative. The negative profiles may belong to other hypophysiotropic hormones and/or to catecholaminergic fibers. Some nerve endings at the ventricular surface of the ependymal cells, in contact with the ventricular fluid, were also LH-RH positive. These nerve endings probably release their secretion into the cerebrospinal fluid.

57 citations


Journal ArticleDOI
TL;DR: In this paper, the heat capacities per unit volume of aqueous solutions of NaCl were measured with a flow microcalorimeter and the molality and temperature range covered were 0.01 to 3 mol kg −1 and 274.65 to 318.15 K. The calculated values of ΔH 2, φ agree within experimental uncertainty with the integral enthalpies of dilution of Ensor and Anderson and of Messikomer and Wood up to 323.15 k

55 citations


Journal ArticleDOI
TL;DR: In this paper, the authors measured the densities and volumetric specific heats of hydrochloric acid, alkali chlorides and bromides, and tetraalkylammonium bromide in 0 to 40% by weighttert-butanol (t-BuOH) with a flow densimeter and a flow microcalorimeter.
Abstract: The densities and volumetric specific heats of hydrochloric acid, alkali chlorides and bromides, and tetraalkylammonium bromides were measured in 0 to 40% by weighttert-butanol (t-BuOH) in water with a flow densimeter and a flow microcalorimeter. The effect of salt concentration was investigated in the case of NaCl. The apparent molal volumes and heat capacities and the derived transfer functions of the electrolytes from water tot-BuOH-water mixtures can be interpreted through solute-solute pair and triplet interactions by analogy with the transfer functions oft-BuOH from water to electrolyte solutions, with the salting-in and salting-out effects, and with the influence of electrolytes on the thermodynamics of micellization. At lowt-BuOH concentrations, the transfer functions seem to be reflecting primarily electrolyte-nonelectrolyte pair interactions. At intermediatet-BuOH concentration, wheret-BuOH associates, the hydrophobic bonding is enhanced by hydrophilic ions through a salting-out effect on monomers and by hydrophobic salts through triplet interaction (mixed association complexes). The Me4NBr and Et4NBr are intermediate electrolytes which do not have much effect on thet-BuOH hydrophobic bonding. At hight-BuOH concentrations the transfer functions tend to the values they would have in puret-BuOH.

53 citations


Journal ArticleDOI
TL;DR: An automatic method of analysis of bowel sound recordings has been developed and it was found that the probability of a sound occurring followed a law similar to that of Poisson's phenomenon.

49 citations


Journal ArticleDOI
01 Nov 1975-Virology
TL;DR: Mouse embryo cells that had been exposed to polyoma virus (Py) labeled in its protein and/or DNA moiety were fractionated at various times after infection and Sedimentation analysis of the cytoplasm revealed the presence of a labeled viral DNA-protein complex, termed NP, which is absent from virus preparations used for infection.


Journal ArticleDOI
TL;DR: In this paper, the "rigid bender" Hamiltonian was used to calculate the vibration-rotation energy levels of triatomic molecules and further the understanding of the anharmonicity in the H bending vibration of HCNO and the centrifugal distortion of HNCO and DNCO.

Journal ArticleDOI
TL;DR: The dynamic flow microcalorimeter designed and built at the Universite de Sherbrooke has been used, with new pumps, to measure enthalpies of mixing of organic liquids as discussed by the authors.

Journal ArticleDOI
01 Dec 1975-BJUI
TL;DR: The influence of vesical distension of the urethral pressure profile was studied in female dogs, using a model in which the bladder and urethra were separated, and was completely blocked by ganglion blocking agents.
Abstract: The influence of vesical distension of the urethral pressure profile was studied in female dogs, using a model in which the bladder and urethra were separated. There was a reduction in the urethral resistance involving its smooth and striated muscle components. This reduction was completely blocked by ganglion blocking agents. Atropine did not influence these changes. Propranolol could only partially block this reflex. The other possible mechanisms that could be involved were discussed.

Journal ArticleDOI
TL;DR: In this paper, the authors derived limiting apparent molal volumes and heat capacities (φco) for specific effects in the hydration of alkyl and aryl-substituted quaternary ions, using also similar results on the tetraalkylammonium series.
Abstract: The density and specific heat of aqueous solutions of Bu4PBr, Ph4PBr, and NaBPh4 have been measured at various temperatures between 10 and 45°C. The derived limiting apparent molal volumes (φvo) and heat capacities (φco) have been examined for specific effects in the hydration of alkyl- and aryl-substituted quaternary ions, using also similar results on the tetraalkylammonium series. While φvo and φco of Bu4PBr and Bu4NBr differ only in magnitude by a few percent, the properties of Ph4PBr are sharply distinct, especially φco. NaBPh4 also exhibits a distinct behavior in the temperature dependence of its φco; the effect, however, is much less pronounced than that previously reported by other investigators. Within the data presently available, φco of hydrophobic ions appears rather invariant with temperature; for the compounds studied here, the relative change in φco with temperature is significantly smaller than the relative change in φvo. These results are correlated with spectroscopic data reported earlier, using a phenomenological description of the two-state behavior of liquid water. The latter is used to calculate the solvent relaxational contribution to the heat capacity of water and to φco of the hydrophobic ions.

Journal ArticleDOI
TL;DR: It is concluded that Crohn's disease is not confined to the gastrointestinal tract, and that early lesions of the disease within theintestinal tract are submucosal rather than mucosal.
Abstract: Three patients with Crohn’s disease primarily involving the large intestine had unusual abscesses of the vulvar area. At biopsy, the abscesses had classic features of the primary disease and were clearly separated from the intestinal tract. There was no fistula in the anal canal, and the perineum between the vulvar abscess and the anus was normal. One of the patients also had an early lesion of Crohn’s disease in the sigmoid. The lesion appeared as a small erythematous spot without ulceration. Biopsy revealed a typical granuloma under an intact mucosa. It is concluded that Crohn’s disease is not confined to the gastrointestinal tract, and that early lesions of the disease within the gastrointestinal tract are submucosal rather than mucosal.

Journal ArticleDOI
TL;DR: The evolution of ultimobranchial bodies in Holtzman rats during the first 64 weeks after birth was studied by reconstructing three‐dimensional models from serial sections stained by the periodic acid‐Schiff technique and the possibility that the ultimOBranchial parenchyma may function as an endocrine gland of holocrine type are discussed.
Abstract: The evolution of ultimobranchial bodies in Holtzman rats during the first 64 weeks after birth was studied by reconstructing three-dimensional models from serial sections stained by the periodic acid-Schiff technique. Radioautography with 125I was made to see if ultimobranchial cells and/or follicular cells lining the lumen of mixed follicles were able to iodinate proteins. The term ultimobranchial body designates herein an embryonic vesicular structure (derived from the third pharyngeal pouch) whose wall is made of a stratified squamous epithelium. During the first week after birth, the vesicular ultimobranchial body elongates rapidly and becomes a canal or a duct. During the second week, cell desquamation brings about local dilatations in the lumen of these ducts; with further enlargement ultimobranchial follicles will appear. In one-day-old rats, mixed follicles are present. Only the follicular component of mixed follicles iodinates proteins as is shown by radioautography. The reconstructed models enlarge rapidly up to the 56th day after birth at which time their weight has increased nineteenfold. These same models show that the three morphological components of ultimobranchial parenchyma, namely ducts, follicles and mixed follicles, are in continuity within the thyroid parenchyma. The formation of new thyroid follicles after birth and the possibility that the ultimobranchial parenchyma may function as an endocrine gland of holocrine type are discussed.


Journal ArticleDOI
TL;DR: The number, total duration, and mean energy of sounds totaled for ten minute periods were found to be markedly influenced by the ingestion of the meal, and food ingestion should be taken into consideration when bowel sounds are interpreted.
Abstract: Bowel sounds were recorded under standard conditions for 30 minutes before, and for 90 minutes after a standard meal in 12 healthy human volunteers. The sounds were analyzed with the aid of a computer, and the evolution in time of specific parameters obtained as a quantitative printout. The number, total duration, and mean energy of sounds totaled for ten minute periods were found to be markedly influenced by the ingestion of the meal. A peak of activity occurred immediately after the meal; the activity then decreased to 85% of premeal value 60 minutes later, and a second peak followed after a further 60 minutes. An excellent correlation (correlation coefficient better than 0.9) was found at two recording sites between the three analyzed parameters, taken in pairs. For any given parameter, a correlation was also found between its value at the two sites (k better than 0.9),but the actual value were significantly different (p <0.001). When bowel sounds are interpreted, therefore, food ingestion should be taken into consideration.

Journal ArticleDOI
TL;DR: In this paper, the sensitivity of mouse liver glucose-6-phosphatase activity towards glutaraldehyde fixation has been analyzed by biochemical and cytochemical means, and it is concluded that several enzymatic differences appear between fixed and unfixed enzymes and that the inhibition by Pb ions is dependent on the buffer and the amount of substrate used.
Abstract: The sensitivity of mouse liver glucose-6-phosphatase activity towards glutaraldehyde fixation has been analysed by biochemical and cytochemical means. The degree of enzymatic inhibition and various enzymatic properties have been studied. Several differences have been observed in the Km determination, the sensitivity to pH 5 and the activity related to pH between fixed and unfixed enzymes. The role of Pb++ ions in the cytochemical media has also been estimated. It is concluded that several enzymatic differences appear between fixed and unfixed enzymes and that the inhibition by Pb ions is dependent on the buffer and on the amount of substrate used.

Journal ArticleDOI
01 Dec 1975-BJUI
TL;DR: Using female dogs, changes in the urethral pressure profile in response to vesical distension were studied and revealed that this increase is not mediated through an autonomic reflex and does not reflect a significant enhancement of alpha-adrenergic activity.
Abstract: Summary Using female dogs, changes in the urethral pressure profile in response to vesical distension were studied. It was noted that during the collecting phase there was an increase in the amplitude of the profile tracing. These experiments revealed that this increase is not mediated through an autonomic reflex and does not reflect a significant enhancement of a-adrenergic activity. These changes are mainly due to increased tension of the urethral muscle, secondly to detrusor stretch.

Journal ArticleDOI
TL;DR: Naproxen, 250 mg twice daily, was significantly better tolerated than aspirin, 900 mg four times daily, and significantly fewer patients terminated their six-week study period on naproxen than on aspirin.
Abstract: One hundred nineteen adults with active definite or classical rheumatoid arthritis were studied in a multicenter double-blind crossover study of naproxen (500 mg/day) and aspirin (3.6 Gm/day). Each drug was given in sequence for a six-week study period. Patients already receiving corticosteriod and/or gold therapy were maintained at constant dose throughout the study, but analgesics and other nonsteroidal antiinflammatory agents were discontinued at baseline. Objective and subjective evaluations by both investigator and patient were carried out at two-week intervals. No significant difference in global evaluation of efficacy or individual measures of efficacy was observed between aspirin and naproxen therapy, although physicians' global evaluation tended to favor naproxen. Sedimentation rate was lower on aspirin (naproxen 43.1 mm/hr; aspirin 38.7 mm/hr; P=0.02). Naproxen, 250 mg twice daily, was significantly better tolerated than aspirin, 900 mg four times daily. Mild, moderate, and severe side effects were less frequent with naproxen. The incidence of heartburn was significantly lower on naproxen, and significantly fewer patients terminated their six-week study period on naproxen than on aspirin. There were no significant deviations from baseline values in hematocrit, white cell or differential counts, or in tests of renal and hepatic function during the course of the study.

Journal ArticleDOI
TL;DR: In this paper, a new stereoelectronic theory for the cleavage of the tetrahedral intermediate in the hydrolysis of esters and amides is presented, based on the orientation of the lone pair orbitals of the heteroatoms.
Abstract: A new stereoelectronic theory for the cleavage of the tetrahedral intermediate in the hydrolysis of esters and amides is presented. In this new theory, the precise conformation of the intermediate hemi-orthoester or hemi-orthoamide controls the nature of the hydrolysis products. It is postulated that the breakdown of a conformer of a tetrahedral intermediate depends upon the orientation of the lone pair orbitals of the heteroatoms. Specific cleavage of a carbon-oxygen or a carbon-nitrogen bond in any conformer is allowed only if the other two heteroatoms (oxygen or nitrogen) each have an orbital oriented antiperiplanar to the leaving O -alkyl or N -alkyl group. Experimentally, the oxidation of acetals by ozone and the acid hydrolysis of a series of cyclic orthoesters demonstrates clearly that there is indeed a stereoelectronic control in the cleavage of hemi-orthoesters. Similarly, a study of the basic hydrolysis of a variety of N , N -dialkylated imidate salts shows that the same stereoelectronic control is operating in the cleavage of hemi-orthoamides.

Journal ArticleDOI
TL;DR: Calcium did not influence the spontaneous release of vasopressin from rat neurohypophyses in vitro when used in concentrations of 0·05, 0·5 and 2·8 mM in the bathing medium.
Abstract: SUMMARY 1. Calcium did not influence the spontaneous release of vasopressin from rat neurohypophyses in vitro when used in concentrations of 0·05, 0·5 and 2·8 mM in the bathing medium. 2. Stimulation of the basal output of vasopressin by angiotensin II (1 · 10–9 M) required at least 0·5 mM calcium in the medium. 3. Angiotensin II stimulated the release of vasopressin within 2·5 min of incubation, maximal release was observed after 10 min. 4. Angiotensin II rapidly promoted the accumulation of tissue cyclic AMP; maximal accumulation was observed after 5 min of incubation. 5. Theophylline and dibutyryl cyclic AMP produced varying degree of stimulation of the release of vasopressin. 6. Increases in vasopressin secretion and in the accumulation of cyclic AMP were always present when neurohypophyses were exposed to optimal concentrations of angiotensin II. The results presented suggested that cyclic AMP may be an intermediate step for the release of vasopressin by endogenous angiotensin II.


Journal ArticleDOI
TL;DR: The scaledparticle theory has been applied to the calculation of the thermodynamic changes associated with the formation of a cavity in several isotopic varieties of liquid water and methanol as discussed by the authors.
Abstract: The scaled-particle theory has been applied to the calculation of the thermodynamic changes associated with the formation of a cavity in several isotopic varieties of liquid water and methanol. From these results, the thermodynamic functions for the transfer of a cavity (or a hard-sphere solute) have been computed for the following solvent pairs: H2O→D2O, H2O→H218O, H218O→D218O, D2O→D218O, CH3OH→CH3OD. For the last two of these solvents, density measurements required for the calculations were carried out as a function of temperature. The calculated deuterium solvent isotope effect on the heats and entropies of hard-sphere solutes in water is much greater than the18O isotope effect; the former also exhibits a more pronounced temperature dependence. The transfer functions computed for hard-sphere solutes are compared to experimental data on the transfer of various solutes from H2O to D2O and from CH3OH to CH3OD. In most of the cases examined, the cavity effect accounts for a large part of the transfer quantities measured for rare gases, hydrocarbons, and solutes containing a significant hydrocarbon substituent.


Journal ArticleDOI
TL;DR: In this article, the infrared spectrum of CH2D2 has been recorded in the region of 1345 to 1561 cm−1 with a resolution of 0.030 to 0.026 cm− 1.

Journal ArticleDOI
TL;DR: While a number of competition variables might be considered, calculations clearly suggest that the ability to disembed a static visual field is not a variable of concern in the understanding of the dynamic visual properties which relate to basketball shooting.
Abstract: The delineation of visual attributes related to the qualiry of athletic performance is not yet clearly established. Research suggccts that basketball shooting performance is meaningfully related to distance perception ( 3 ) and dynamic visual acuity ( I ) , while relarively unrelated to measures of depth perception ( 4 ) and visual imagery ( 5 ) . Other properties such as visual disembedding have yet to be considered in relation to successful basketball shooting. Visual disembedding refers to the ability to break u p an organized visual field in order to keep a part of it separate from its surroundings. The task is static like those used for depth perception and imagery and is c!aimed to be the core trait of globs!-analytic cognitive style ( 6 ) . T o estimate the correlation between efficiency of basketball shooting and ability to disembed a complex visual field. 1 1 male (M,,, , = 20.7 yr., SD = 1.01) , and 9 female (M... = 20.5. SD = 1.93) sophomore and junior varsity basketball players, enrolled at Florida State University were administered the Group Hidden-figures Test, an adaptation of the Gottschaldt Figures Test ( 2 ) . The task required subjects to determine which of five simple figures was embedded in a more comp'ex pattern. The test was administered midway in the basketball season. Scores were correlated with the seasonal fieldgoal and free-throw shooring efficiency of each subject. Efficiency ratings were the ratio of successful shots to the total attempts during competition. A minimum of 20 and 1 0 attempts in the field-goal and free-throw caregories respectively were established as criteria for including subjects' data. Mean number of field-goal attempts = 184.3, SD = 115.1 for the males, and 138.6. SD = 72.4 for the females; mean number of freethrow attempts = 47.3, SD = 20.9 for the males, and M = 60.2, SD = 34.9 for the females. The Group Hidden-figures Test scores were not significantly correlated with either percentages of free throws (males -.41; females -.05) or field goals (males .16; females --.21). While a number of competition variables might be considered, these calculations clearly suggest that the ability to disembed a static visual field is not a variable of concern in the understanding of the dynamic visual properties which relate to basketball shooting.