Showing papers by "University of Montpellier published in 1974"

De Subitaneis Mortibus IX. Type A Wolff-Parkinson-White Syndrome

Abstract: A twenty-two-year-old woman with type A Wolff-Parkinson-White syndrome had a long history of paroxysmal tachycardia and died of a stroke. Until the last two years of life the tachycardias responded to medical treatment, but thereafter they could only be terminated with electrical shock. During one such shock her sinus rhythm disappeared and for over a year she had only atrioventricular (A-V) junctional rhythm although paroxysms of tachycardia persisted. Special studies of the heart after death included serial sections of the entire A-V ring. Nonspecific degenerative disease of both atria included the internodal pathways. Both the sinus node artery and the A-V node artery were narrowed by mural thickening. The sinus node was generally intact but virtually all atrionodal connections were degenerated. The A-V node was similarly detached from its atrial connections but was in direct continuity with the His bundle. The right bundle branch was interrupted at its origin. Within the central fibrous body there were numerous lacunae and one long cleft extending from atrial to ventricular septum parallel to the A-V node. Although the cleft contained cells, there was no direct A-V connection. At the right lateral A-V junction a long thin cylinder of Purkinje cells lay parallel to the tricuspid valve ring and connected to the atrium but not the ventricle. Beneath the left atrial appendage there was a fault in the mitral annulus through which there was a direct A-V connection. Most of this connection was composed of P cells and thus resembled the patient9s own sinus node. The atrial connection was to Bachmann9s bundle, which was extensively degenerated. The ventricular connection was to ordinary working myocardium midway between epicardium and endocardium. Some functional implications of these anatomical findings are discussed.

Differences between the Estradiol and Tstosterone Receptors in Rat Uterus

Abstract: Immature rat uteri contain specific binding proteins for both estradiol and testosterone. In an attempt to compare these two hormonal sites and to determine their localisation, the following was successively established. 1 Testosterone did not compete with [3H]estradiol (3 nM) for the estrogen receptor sites, whereas high concentrations of estradiol did compete with [3H]testosterone on the androgen receptor. 2 After incubation of uteri at low physiological concentration of testosterone, the majority of the testosterone receptor sites was localised in the nucleus, whereas the estradiol receptor sites were found in the cytosol fraction. For higher concentration (≥ 100 nM) of testosterone the two steroid receptor sites were mainly present in the nuclear fraction. 3 The complexes of [3H]testosterone and [14C]estradiol with cytosol receptors, when simultaneously prepared and analysed, were shown to behave differently after sucrose-gradient ultracentrifugation and Sepharose chromatography. These results strongly suggest that the receptor sites for testosterone and estradiol in rat uterus are localised on two different multi-unit proteins in which the steroid binding units are different.

Internal friction in phosphoaluminate and borate glasses

Abstract: Internal friction in sodium phosphoaluminate and borate glasses was investigated by torsion pendulum, beam vibration and pulse-echo methods. The Arrhenian relationship was verified in a frequency interval covering eight decades. A detailed analysis of the first peak was made to obtain the distribution of relaxation times and the distribution of activation entropy ΔS and activation enthalpy ΔH . The log-normal distributions were further compared to the Doremus theory and the observed discrepancy discussed.

Effect of Time of Administration of an Inflammatory Agent on Plasma Corticosterone and Haptoglobin Levels in the Rat

Abstract: In order to examine the influence of the clock hour at which an acute inflammatory reaction is induced on the kinetics of both corticosterone and haptoglobin hyperproduction, turpentine oil was administered sc to female rats (05 ml⁄100 g body wt), kept under a 12 hr light- 12 hr dark light regimen, at 09 hr, 13 hr, 21 hr and 03 hr In each experiment 15 groups of 5 animals were sacrificed at time intervals ranging from 10 min to 120 hr after injections (ai) The plasma samples were assayed for corticosterone (C) by an improved fluorometric method, and for haptoglobin (Hp) by the peroxidatic activity of a haptoglobin-hemoglobin complex (Jayle, 1951) The C hypersecretion exhibited in the 4 groups a biphasic pattern The first, stressinduced C increase attained in all groups the same ceiling level (about 100 µg⁄100 ml) However the time lag ai of the C peak varied from 20 min in the 15 hr or 21 hr-injected rats, to 1 to 2 hr in the 03-hr stressed animals The secondary, long-lasting C augmentation sta

A neutron small angle scattering study of SiO2Na2 O glasses

Abstract: The first results obtained by small-angle neutron scattering (SANS) study of sub-liquidus immiscibility of glasses are presented. Measurements were performed on the neutron small-angle scattering spectrometer of the Institut Laue-Langevin (Grenoble, France). The glass studied was 0.88 (SiO2), 0.12 (Na2O) from SiO2Na2O system which presents a well-known miscibility gap already explored by small-angle X-ray scattering (SAXS) method. Absolute values of the neutron scattering cross section as a function of scattering vector were obtained for this glass quenched and heat treated at 560°C for various lengths of time. It is shown that the ANS method can be used to follow phase separation kinetics and the comparison with SAXS results can in principle be used to separate the effects of density and concentration fluctuations in this system.

Les espérances mathématiques, les variances et les covariances de quelques variables aléatories associées à des familles de figures convexes dans les espaces euclidiens à deux et trois dimensions

Abstract: SiaE uno spazio euclideo a due o tre dimensioni,K 0 una figura convessa fissa e {K 1,K 2,...,K m} un sistema dim figure convesse, aleatorie come posizione, indipendenti, uniformemente distribuite inE, intersecantiK 0 e congruenti ad una figura convessaK. SiaK m r la figura ottenuta come intersezione diK 0 conr dellem figureK 1,K 2,...,K m. SeE≡E 2, consideriamo come variabili aleatorie l'areas m r e la lunghezzal m r diK m r e, seE=E s, il volume V m r , l'area S m r e l'integrale della curvatura media Open image in new window della frontiera ∂K m r . In questo lavoro determineremo le varianze σ2(s m r e σ2 (V m r , le covarianzeE[s m/r 1 s w/r 2 ] e\(E[\mathcal{V}_m^{r_1 } \mathcal{V}_m^{r_2 } ]\), i valori mediE[l m m ], Open image in new window .

Mechanical Properties and Microstructure of Glass Ceramics and Phase Separated Glasses

Abstract: The mechanical properties of glass-ceramics depend not only on the nature of the precipitated phases and the glassy matrix but also on the microstructure (texture) of the material. It is the aim of this paper to review: a) Experimental techniques available to characterise glassceramics; and, b) Theories correlating their mechanical strength and microstructure.