Showing papers by "Pierre-and-Marie-Curie University published in 1975"
TL;DR: The results can be considered as evidence that the mechanism of analgesia from the inferior raphe nucleus is similar to that already described in the dorsal Raphe nucleus, which seems to be sustained by serotoninergic mechanisms.
Abstract: In the cat, electrical stimulation of the inferior central nucleus of the raphe induces a powerful analgesia. This stimulation totally suppresses the behavioural reactions elicited by strong pinches applied to the tail or to the four limbs; it strongly modifies the threshold of the jaw opening reflex obtained by tooth pulp stimulation and considerably affects the behavioural reactions elicited by continuing such stimulation. The results can be considered as evidence that the mechanism of analgesia from the inferior raphe nucleus is similar to that already described in the dorsal raphe nucleus. The analgesia obtained by stimulation of raphe nuclei seems to be sustained by serotoninergic mechanisms and relationships between these are discussed. In preliminary experiments, analgesia induced by CI stimulation has been suppressed by administration of naloxone, a specific opiate antagonist.
305 citations
TL;DR: It is concluded that the smooth endoplasmic reticulum appears as a continuous intraaxonal pathway bridging the perikaryon and the axon terminal; the SER conveys macromolecular components with the fast axonal transport; and the conveyed Macromolecules are probably transferred by means of connections with the SER.
288 citations
TL;DR: In this paper, a comparison of the β-, ϵ-, γ-, and δ-type GaSe crystal structures, the different interlayer interactions are discussed, and influence of the growth method on crystal type and dislocation density are discussed.
Abstract: After a comparison of the β-, ϵ-, γ-, and δ-type GaSe crystal structures, the different interlayer interactions are discussed. New values for the intralayer interatomic distances Se–Ga = 2.463 (15) A, Ga–Ga = 2.457 (18) A, and the interlayer distance Se–Se = 3.880 (15) A are proposed. These are mean values for the δ-type determined with a higher accuracy than the previous ones, relevant to the ϵ- and γ-type structure. The influence of the growth method on crystal type and dislocation density are discussed.
238 citations
TL;DR: The effects of morphine upon the transmission of nociceptive messages at the spinal level have been investigated in spinal cats by studying its effects on the activities of lamina V dorsal horn interneurons and depressive effects are observed.
205 citations
TL;DR: In this paper, the static and dynamical correlations of density fluctuations in a classical one-component plasma (OCP), in the framework of thermodynamic fluctuation theory and linearized hydrodynamics, were studied.
Abstract: We study the static and dynamical correlations of density fluctuations in a classical one-component plasma (OCP), in the framework of thermodynamic fluctuation theory and linearized hydrodynamics. First we show that the fluctuations of the local electric field stabilize the OCP against density fluctuations, even when the compressibility becomes negative for $\ensuremath{\Gamma}\ensuremath{\gtrsim}3$, where $\ensuremath{\Gamma}$ is the usual plasma coupling parameter. Then, following closely the work of Mountain, we compute the dynamical structure factor in the hydrodynamic limit and show that the thermal Rayleigh peak vanishes in the long-wavelength limit, in agreement with recent molecular dynamics results. The shear and bulk viscosity coefficients $\ensuremath{\eta}$ and $\ensuremath{\zeta}$ are calculated for large $\ensuremath{\Gamma}$ in the framework of the "generalized hydrodynamics" formalism, using the known short-time expansion of the correlation functions. The coefficient $\ensuremath{\eta}$ is found to exhibit a minimum as a function of $\ensuremath{\Gamma}$ and $\ensuremath{\zeta}$ is found to be negligible compared to $\ensuremath{\eta}$ in the OCP.
142 citations
TL;DR: The time course of blood acid-base changes was studied in Carcinus maenas during experimental emersion and reimmersion at 15 degrees C by measuring pH and PCO2 and calculating bicarbonate concentration to agree with the general views concerning the blood acid -base changes which must occur at transition from water-to air-breathing.
112 citations
104 citations
TL;DR: The observations suggest that the functional oxygen affinity of the pigment is physiologically regulated to ensure an adequate oxygen transport by the blood in quite varied conditions of temperature and salinity.
102 citations
TL;DR: In this paper, the electron impact excitation of H2O and D2O has been studied at electron energies close to threshold and at large scattering angles in order to enhance spin and/or symmetry forbidden electronic transitions.
Abstract: The electron‐impact excitation of H2O and D2O has been studied at electron energies close to threshold and at large scattering angles in order to enhance spin and/or symmetry forbidden electronic transitions; and at energies far from threshold and at small scattering angles to enhance optically allowed transitions. The energy‐loss range covered is 4.2–12 eV. From a comparison of the present measurements and recent, accurate ab initio calculations, several new assignments of electronic transitions in both H2O and D2O have been made or suggested. Also suggested are future works which could be carried out in order to unravel the complex Rydberg spectra above 11 eV.
77 citations
TL;DR: In this article, a method for detecting the formation of a complete, binary, monolayer was proposed. But this method requires that the second absorbate (typically, an easily deposited metal) forms first on the uncovered substrate and then on top of the first adsorbate by a layer-by-layer growth mechanism.
61 citations
TL;DR: In this paper, a series of NiO samples has been prepared from Ni(OH)2, at low temperature, in air flow, and the starting hydroxide is obtained from a Turstratic Hydroxide in the form of thin platelets suitable for electron microscopy and selected area diffraction studies.
TL;DR: The method of spreading transcription complexes has been applied to amphibian oocytes of the Pleurodeles genus as discussed by the authors, and two main characteristics can be drawn: the existence of several transcription units in a chromosomal organization unit and the possibility to point out a special architecture at the RNP fibril level.
Abstract: The method of spreading transcription complexes has been applied to amphibian oocytes of Pleurodeles genus. Complexes of nucleolar origin show a regular and homogeneous organization similar to that described in other materials. The observations add to the interpretation as an amplification of nucleolar DNA and a redundancy of ribosomal cistrons in the two species studied. -- On the other hand, complexes of chromosomal origin display a great diversity. Two main characteristics can be drawn: the existence of several transcription units in a chromosomal organization unit and the possibility to point out a special architecture at the RNP fibril level. Applying a shadowing technique used for isolated molecules is an improvement compared with earlier methods based on PTA coloration.
TL;DR: Using suspension-cultured Acer pseudoplatanus cells requiring 2,4-dichlorophenoxyacetic acid for growth, the dependence of the population doubling time and the maximum increase in cell population density on the auxin concentration was studied.
Abstract: Using suspension-cultured Acer pseudoplatanus cells requiring 2,4-dichlorophenoxyacetic acid for growth, the dependence of the population doubling time and the maximum increase in cell population density on the auxin concentration was studied. It appears that in the range of 2,4-dichlorophenoxyacetic acid concentration from 4 × 10−8 to 4 × 10−6 M, the rate of cell division during the logarithmic growth phase is independent of the auxin concentration, while the maximum number of cell generations obtained is limited by the initial auxin concentration. The significance of these two aspects of auxin action are discussed.
TL;DR: The data suggest that hypophyseal corticostimulating activity is very high between days 18 and 19 and decreases between days 19 and 21, and that Adrenal and plasma corticosterone concentrations reach a peak on day 19 of pregnancy.
Abstract: Pituitary sections from 15 to 21 day-old rat foetuses have been studied with the immunofluorescence technique, using antibodies anti α-MSH, anti β-MSH and anti β (1–24) ACTH. The first ACTH cells appear on day 17 of pregnancy in the pars distalis of the hypophysis and only on day 18 in the pars intermedia. β-MSH cells have been observed on day 16 in the pars anterior and on day 17 in the pars intermedia, while α-MSH cells appear only on day 18 and exclusively in the pars intermedia. The cytodifferentiation of the β-MSH and ACTH cells occurs in the pars intermedia with about a 24 hour delay in comparison to that of the pars distalis. The first revealed cells are always located in the posterior half of the pituitary gland. The corticostimulating activity of the hypophysis has been tested with the fluorescence intensity of the corticotrophs, the adrenal weight, the adrenal content in corticosterone and the plasma corticosterone level. The fluorescence of the corticotrophs increases on day 18, shows a maximum on day 19 and decreases until term. The adrenal weight rises regularly between day 16 to day 20, thereafter the increase subsides. Adrenal and plasma corticosterone concentrations reach a peak on day 19 of pregnancy. These data suggest that hypophyseal corticostimulating activity is very high between days 18 and 19 and decreases between days 19 and 21.
TL;DR: The results suggest that PC are directly affected by the mutation, and depth profiles during antidromic invasion of PC and unitary antidromics responses revealed a lower safety factor than normal in the invasion of the somatodendritic region of PC.
TL;DR: In this article, the vOH bands of some liquid alcohols (three primary, two secondary and one tertiary) have been studied over a wide temperature range with regard to: (i) band position as a function of temperature, (ii) band intensity and depolarization ratio, and (iii) physical state.
Abstract: The vOH (OD) bands of some liquid alcohols (three primary, two secondary and one tertiary), have been studied over a wide temperature range with regard to: (i) band position as a function of temperature, (ii) band intensity and depolarization ratio as a function of temperature and physical state.
From studies of (i), the long chain polymer structure is confirmed; and the diagonal and interaction force constants FOH and ƒOH are calcualated between 295 K and the melting point. From studies of (ii), it is shown that the intensity in the liquid phase is temperature independent as long as autoassociation is preponderant: however from relative intensity measurements (gas to liquid) the scattering activity is seen to increase by a factor of two as a result of autoassociation; and the depolarization ratio increases by a factor of two from dilute solution to pure liquid.
These results are discussed in the light of the bond polarizability theory; it is concluded that the α′l/α′p ratio for the OH band changes considerably on formation of an hydrogen bond. This can be explained in terms of the Orville Thomas pulsed cloud model.
TL;DR: In this paper, it was shown that it is always possible to determine an extension of a strict partial order to a strict weak order that preserves simultaneously some order denseness and topological properties, and sufficient conditions for the existence of an upper semicontinuous utility on a strictly partially ordered space were derived.
TL;DR: This work uses isolated pollen grain culture from Petunia to determine precisely the stage at which pollen elicits the best androgenic response, with a view to increasing the yield of haploid plants thus produced.
Abstract: THE ease with which plantlets can be produced from somatic tissue, protoplasts and anther cultures of Petunia1–3 has prompted us to use isolated pollen grain culture4 to determine precisely the stage at which pollen elicits the best androgenic response, with a view to increasing the yield of haploid plants thus produced.
TL;DR: In this article, the external layers of some zeolite surfaces were studied using X-ray photoelectron spectroscopy (XPS) and it was shown that the (Si/Al) ratio of the external surface is roughly twice that of the bulk.
TL;DR: Steroid-protein interactions were studied in various urodelan and anuran amphibians: Pleurodeles waltlii, Salamandra salamandra, Amby stoma mexicanurn, Rana temp oraria and Discoglossus pictus, finding proteins with high steroid affinity and limited capacity found in all amphibian species studied.
Abstract: Steroid-protein interactions were studied in various urodelan and anuran amphibians: Pleurodeles waltlii, Salamandra salamandra, Amby stoma mexicanurn, Rana temp oraria and Discoglossus pictus. The detection of specific steroids binding serum proteins was determined by equilibrium dialysis and sucrose gradient centrifugation experiments. Binding constants were determined by using an equilibrium dialysis-scatchard plot method. Amphibians possess proteins with high steroid affinity and limited capacity. These proteins may be classified in two groups according to their specificity: a) the proteins binding specifically C21 steroids or “Amphibian corticosteroid binding protein” (A.CBP). The binding constants of corticosterone were determined in four amphibian species; in Rana tern poraria serum, the association constant (Ka) at 4 C was 8.2 X 108 M-1, and the binding capacity was 1.3 X 107M. b) the proteins binding specifically C18 and C19 sex steroids or “Amphibian sex steroid binding protein” (A.SBP). These proteins were found in all amphibian species studied. In Rana temporaria serum, Ka values for estradiol-17�3 and testosterone were respectively 5.1 x 108 M-1 and 1.3 X io�
TL;DR: In this article, the authors used potentiometric titration to identify Cu(II)-poly(L-arginine) complexes by optical, circular dichroism, and infrared spectra, providing information about the nature of ligands and the coordination sphere around the metal ion.
Abstract: The study of Cu(II)–poly(L-arginine) complexes by potentiometric titration, as well as by optical, circular dichroism, and infrared spectra, provides information about the nature of ligands and the coordination sphere around the metal ion. Three different complexes have been identified. The first, which is formed below pH 8, contains two guanidinium nitrogens and two water molecules at the corners of the coordination square. The constant of the overall process as determined by the Gregor method equals 2.0 ± 0.1 × 10−9. The two other complexes form between pH 8 and 10.5 and they contain two guanidinium and two peptide nitrogens as nearest ligands. One of them is a monomer and the other probably a dimer, which differ in the symmetry of the coordination sphere around the cupric ion. The optical spectra of the three complexes show an absorption band at 260 nm that we have assigned to a charge-transfer transition between a σ metal nitrogen (amine) molecular orbital and a dx2−y2 metal orbital. The spectra of the two complexes containing peptide nitrogens exhibit another absorption band at 320 nm, which we have assigned to a charge transfer from a π orbital of the amide group to the dx2−y2 metal orbital.
TL;DR: The chemical quality of Mekong waters was found highly variable (total ionic content ranged from 60 to 190 mg l−1). As usual concentrations C decrease with increasing discharge Q according to the relation C = aQb, with −1 < b < 0.1 as mentioned in this paper.
TL;DR: In this article, the free energy and equation of state of the ionic plasma were calculated to order h4 in the Wigner expansion, and a correction was made to the equation-of-state equation.
TL;DR: The clones were most sensitive to ecdysone between the 3rd and the 7th month of their development, and the specific sensitivity to β-ecdysone of subclones derived from the above clones was established with greater precision.
01 Jan 1975
TL;DR: The addition of alkylcopper compounds to various alkynes shows a regio-selectivity dependant on various factors, the major factors being the nature of the function and the solvent as discussed by the authors.
TL;DR: In this paper, les methodes de correlation sont bien adaptees for analyser les comportements deterministe et stochastique d'une interface electrochimique.