Más sobre latín tardío y romance temprano

1991

This article discusses the new approaches to dating the origins of the Romance languages having appeared as a consequence of the thesis of R. Wright -wich broke with the theory of two traditionally accepted norms postulating one single language up to the Carolingian reforms- while surveying studies originated by the thesis, its degree of acceptance and some of the major objections which have been raised.

A boundary min-max principle as a tool for boundary element formulations

1991

Abstract A min-max principle for elastic solids, expressed in terms of the unknown boundary displacements and tractions, is presented. It is shown that its Euler-Lagrange equations coincide with the classical boundary integral equations for displacements and for tractions. This principle constitutes a suitable starting point for a symmetric sign-definite formulation of the boundary element method.

Urachal remnants in asymptomatic children: sonographic morphology.

1991

The sonographic morphology of urachal remnants is not well known and findings tend to be misinterpreted. We present urachal remnants in 16 asymptomatic children (1 week-16 years). In the prevesical part two different types of urachal remnants were found: the tubular type with a small outer muscle wall and the fusiform type with a muscle wall thickness up to 12 mm. Further subvariants are presented. Differential diagnosis of the fusiform type includes urachal cyst and tumorous muscle thickening.

Orientational glass transition in quadrupolar glasses

1991

Anomalous intensity of the 335 cm−1 phonon in YBa2Cu3O7−δ

1991

Abstract We report results on Raman scattering for the intensity of the 335 cm −1 phonon of A g (pseudo B 1g ) symmetry in thin YBa 2 Cu 3 O 7−δ films on MgO and LaAlO 3 substrates. The intensity of this phonon shows a pronounced increase below 100 K and saturates at low temperatures. We also observe an additional intensity peaking at temperatures close to the superconducting transition T C . This may indicate a structural phase transition in the vicinity of T C .

Observation of the decay KLO→ e+e−ep+e−

1991

Abstract Two events with the characteristic of the decay K L O → e + e − e − have been observed with a negligible expected background from which a branching ratio of (4±3)×10 −8 is derived. This result is consistent with values estimated from theoretical models based on the double internal conventional of the decay K L O → γγ .

Regulation of fructose 2,6-bisphosphate in perfused flight muscle of the locust, Locusta migratoria: The effect of octopamine

1991

The concept of major depression. I. Descriptive comparison of six competing operational definitions including ICD-10 and DSM-III-R.

1991

All operationalized diagnostic systems contain a diagnostic category, which corresponds to the concept of major depression. Yet, these corresponding definitions are not identical. Up to now, no comprehensive comparisons of the competing diagnoses have been published. We will therefore present a series of studies, describing six different operational definitions of major depression according to their content and construction and empirically comparing them in large inpatient and outpatient samples. This first paper presents a descriptive comparison of the definitions given in the Feighner Diagnostic Criteria, the Research Diagnostic Criteria, the Diagnostic and Statistical Manual of Mental Di…

Selective loss of pertussis toxin-sensitive G-proteins from the plasma membrane after antibody-induced internalization of T-cell surface molecules.

1991

Antibody-induced antigenic modulation occurs after binding of antibodies to a variety of cell surface proteins. It is characterized by aggregation and subsequent loss of the molecules from the cell surface, usually by internalization. In this study we have investigated the effect of modulation of the T-cell antigen receptor complex (TCR) and the transferrin receptor (TFR) on the distribution of cholera toxin (CTx)- and pertussis toxin (PTx)-sensitive GTP binding proteins in human T-lymphocytes. Modulation of both the TCR and the TFR induced a selective shift of PTx-sensitive G-proteins from the plasma membrane to a high density membrane fraction enriched for lysosomal membranes. The distrib…

Microgel regions in dilute agarose solutions: the notion of non-gelling concentration, and the role of spinodal demixing

1991

Abstract Freely drifting microgel regions are found in aqueous solutions of agarose, a representative biostructural polysaccharide, at concentrations between 0.01% and 0.05% w/v when quenched from 100°C to lower temperature. The size of these domains depends on the quench temperature and agarose concentration. The results agree with recent findings on the role that fluctuations within or close to the instability region of solution have as the initial step towards the self-assembly of supramolecular structures, and throw a new light on the notion of the lowest solute concentration needed for gelation.

Chronic Osteomyelitis with Bone Sequestrum Penetrating the Bladder Wall

1991

The role of the claustrum in the bilateral control of frontal oculomotor neurons in the cat.

1991

The effect of claustrum (CL) stimulation on the spontaneous unitary activity of ipsi and contralateral frontal oculomotor neurons, was studied in chloralose-anaesthetized cats. A total of 205 units was bilaterally recorded in the medial oculomotor area, homologous of the primate "frontal eye fields"; 127 neurons were identified as projecting to the superior colliculus; for 33 of these last units stimulation of the ipsilateral CL provoked an excitatory effect lasting 10-25 ms and appearing with a latency of 5-15 ms; on 8 units the excitatory effect was followed by an inhibition lasting 100-250 ms. Ninety-eight of the 127 neurons were also tested through activation of the contralateral CL: 13…

COOLING-INDUCED CONTRACTION OF TRACHEA ISOLATED FROM NORMAL AND SENSITIZED GUINEA-PIGS

1991

Fast (−7°C/min) cooling of guinea-pig isolated trachea produced a rapidly developing, transient contraction followed by relaxation. Cooling-induced contraction was dependent on temperature (30, 20 or 10°C) and responses in trachea obtained from actively sensitized guinea pigs were significantly greater (20 and 10°-C) than those observed in normal trachea. Cooling to 20°C was selected for subsequent experiments. Pre-treatment with sufficient concentrations of atropine, clemastine, cromoglycate, indomethacin, or nordihydroguaiaretic acid did not depress contraction to cooling in either normal or sensitized trachea. This indicates a direct effect of cooling. The contraction. produced by coolin…

Spinodal decomposition of a two-dimensional model alloy with mobile vacancies

1991

Abstract Monte Carlo simulations are performed for the initial stages of phase separation in a model binary alloy (AB), where unmixing is caused by a repulsive energy between atoms of different kind ( e AA = e BB = e ), and a small fraction c v of mobile vacancies is present (typically c v = 0.04.) Unlike previous work, where interdiffusion was modelled in an unrealistic way by direct interchange of A and B atoms for c v = 0, were use the vacancy mechanism of diffusion: A-atoms may jump to vacant sites with a rate Γ A and B-atoms may jump to vacant sites with a rate Γ B , no direct A–B interchange being permitted. It is shown that the overall time-scale on which phase separation proceeds ty…

Progressive calcifications of lung and liver in neonatal herpes simplex virus infection

1991

We report a female neonate who developed severe septicemia presenting with pneumonia and hepatitis due to an infection with herpes simplex virus type II. In spite of antiviral as well as intensive care therapy, three weeks after admission, extensive hepatic calcification was demonstrable on abdominal radiograph, a sign of severe cellular necrosis. In contrast the pulmonary infiltration recovered completely. The clinical follow up was completed by ultrasound and radiography. The infant died at the age of two months secondary to severe postnecrotic hepatic failure. At autopsy, histological evaluation confirmed the former diagnostic and technical findings; in addition, pulmonary calcifications…

Graves ophthalmopathy: role of MR imaging in radiation therapy.

1991

Twenty-three patients with Graves ophthalmopathy who underwent radiation therapy were monitored by means of magnetic resonance (MR) imaging. T2 relaxation times of extraocular muscles and orbital fat, areas of extraocular muscles, and degree of exophthalmos were measured by means of MR imaging at the beginning, at the end, and 3 months after completion of radiation therapy. As a result, patients with primarily elevated T2 times of extraocular muscles showed a better therapy response regarding muscle thickening than patients with primarily normal T2 times. Elevated T2 times, which probably represent acute inflammatory changes, were markedly decreased at the end of therapy. Therefore, quantit…

Studies in organic mass spectrometry. Part 9—mass spectra of 9,10-disubstituted 2,3,6,7-tetraalkoxy-9,10-dihydroanthracenes: A remarkable loss of rad…

1991

The electron impact-induced fragmentations of 23 9,10-disubstituted 2,3,6,7-tetraalkoxy-9,10-dihydroanthracenes, including six stereoisomeric pairs, were studied. The loss of the 9-(or 10-)substituent constitutes the main fragmentation route. The resulting ions give rise to a remarkable violation of the so-called even-electron rule as they eject the second substituent at the 10-(or 9-)position as a radical. The latter aspect was particularly investigated with the aid of low-energy (nominal value 15 eV) and mass-analysed ion kinetic energy spectra

Book Review: Reviews in Computational Chemistry. Edited by K. B. Lipkowitz and D. B. Boyd

1991

Measurement of B- mixing at the Z

1991

Abstract From more than 175 000 hadronic Z decays observed with the ALEPH detector at LEP, we select 823 events with pairs of leptons in the final state. From these we measure χ , the probability thata b hadron which is observed to decay originated as a b hadron. We find χ =0.132 −0.026 +0.027 .

Hydrophilic and Hydrophobic Polymeric Derivatives of Anti-Inflammatory Agents Such as Alclofenac, Ketoprofen, and Ibuprofen

1991

Macromolecular prodrugs of a hydrophilic polymer [α,β-poly( N- hydroxyethyl)-DL-aspartamide (PHEA)] was used as a drug carrier. Three poly- (HEA)-NSAID adducts were studied: poly(HEA)-Alclofenac, poly(HEA)-Keto profen, and poly(HEA)-Ibuprofen. Prodrugs with different drug content were synthesized both as water-soluble and water-insoluble agents. Hydrolysis of water-soluble adducts in a simulated gastric juice was studied.

Glucose/galactose malabsorption caused by a defect in the Na+/glucose cotransporter.

1991

Glucose/galactose malabsorption (GGM) is an autosomal recessive disease manifesting within the first weeks of life and characterized by a selective failure to absorb dietary glucose and galactose from the intestine. The consequent severe diarrhoea and dehydration are usually fatal unless these sugars are eliminated from the diet. Intestinal biopsies of GGM patients have revealed a specific defect in Na(+)-dependent absorption of glucose in the brush border. Normal glucose absorption is mediated by the Na+/glucose cotransporter in the brush border membrane of the intestinal epithelium. Cellular influx is driven by the transmembrane Na+ electrochemical potential gradient; thereafter the sugar…

Mass spectrometric identification of the amino donor and acceptor sites in a transglutaminase protein substrate secreted from rat seminal vesicles.

1991

Four different transglutaminase-modified forms of a protein secreted by the rat seminal vesicles (SV-IV) were synthesized in vitro and characterized. FAB maps of both the native protein and its derivatives, produced by the purified guinea pig liver enzyme in the presence or absence of the polyamine spermidine, were obtained by mass spectrometric analysis after proteolytic digestions. Two differently derivatized SV-IV molecular forms, both possessing only one glutamine residue out of two (Gln-86) cross-linked to endogenous lysine residues, were produced when spermidine was omitted from the reaction mixture: (i) an insoluble homopolymer in which Lys-2, -4, -59, -78, -79, and -80 were involved…

Safety and side effects of human and ovine corticotropin-releasing hormone administration in man.

1991

Synthetic human and ovine corticotropin-releasing hormone (hCRH, oCRH) are commonly used as a diagnostic tool of the hypothalamo-pituitary-adrenal axis. In this paper reports about side effects after various modes of CRH-application are analyzed and compared to our corresponding data of human studies with hCRH and oCRH. Generally, CRH is well tolerated after single administration and interval-application of standard doses, although minor side effects appear sometimes after higher doses (greater than 200 micrograms hCRH, oCRH) of CRH-bolus-injections. Predominantly the cardiovascular system (e.g. tachycardia, hypotension, flushing) is affected; neuropsychological symptoms are only seen spora…

Functional size of complement and perforin pores compared by confocal laser scanning microscopy and fluorescence microphotolysis

1991

Abstract Confocal laser scanning microscopy and fluorescence microphotolysis (also referred to as fluorescence photobleaching recovery) were employed to study the transport of hydrophilic fluorescent tracers through complement and perforin pores. By optimizing the confocal effect it was possible to determine the exclusion limit of the pores in situ, i.e. without separation of cells and tracer solution. Single-cell flux measurements by fluorescence microphotolysis yielded information on the sample population distribution of flux rates. By these means a direct comparison of complement and perforin pores was made in sheep erythrocyte membranes. In accordance with previous studies employing a v…

Localized Motion in Supercooled Glycerol as Measured by 2 H-NMR Spin-Lattice Relaxation and Incoherent Neutron Scattering

1991

Selectively deuterated glycerol has been subjected to 2H-NMR spin-lattice relaxation and quasi-elastic neutron scattering experiments. The measurements yield relaxation rates and a non-Gaussian Q-dependence of the Debye-Waller factor which are different for the two hydrogen sites. The data analysis shows that below the onset of the glass transition α-process the hydrogens perform a local motion (≈ 10-12 s) in addition to what is expected from harmonic phonons. The resulting mean-square displacements are highly temperature dependent but are significantly smaller than those found in van der Waals glasses. Amplitudes and activation energies of the carbon-bonded and oxygen-bonded hydrogens are …

Caution. Arrêt du cours des intérêts, Bénéfice (oui)

1991

International audience

X-ray scattering studies of the structure of aqueous hydroxy-propylcellulose solutions

1991

X-ray diffraction studies have been undertaken on aqueous solutions of hydroxy propylcellulose (HPC) over a wide range of the scattering vector Q. The experiments revealed only modest differences in local structure on a distance scale ca. 5–300 A despite the fact that they covered concentrations generally interpreted as ranging from the isotropic (35.1 wt %) to the anisotropic liquid crystalline (LC) phase (53.5 wt %). Several models were used to interpret the small-angle scattering data, and each gave similar structural parameters and extrapolated intensities (Q → 0) for both solutions. Peaks were observed with d-spacings ca. 12–17 A in both materials. Wide-angle x-ray scattering (WAXS) sh…

4-Aminopyridine and barium chloride attenuate the anti-epileptic effect of carbamazepine in hippocampal slices

1991

The exact mode of action of the anti-epileptic agent carbamazepine is unknown. In hippocampal slices in which epileptiform discharges were induced by addition of penicillin to the perfusion medium, the depressant effect of carbamazepine was attenuated by the potassium-channel blockers barium chloride (0.1 mM) and 4-aminopyridine (200 microM), which suggested that potassium fluxes might be involved in the mechanism of action of carbamazepine.

Cautionnement. Défaut de déclaration par le créancier dans le délai réglementaire, Déclaration par la seule caution, Extinction de plein droit de la …

1991

International audience

Physiological changes in glutathione metabolism in foetal and newborn rat liver

1991

Glutathione metabolism was studied in isolated hepatocytes from foetal, newborn and adult rats. The GSH/GSSG ratio decreased 15-20-fold through the foetal-neonatal-adult transition. This was mainly due to an increase in GSSG. All enzyme activities involved in the glutathione redox cycle tend to increase during that transition, but the relative increases in glutathione peroxidase and glutathione S-transferase were 3-5 times those of glutathione reductase or glucose-6-phosphate dehydrogenase. GSH synthesis from methionine as a sulphur source was 6 times lower in foetal than in adult hepatocytes. However, when N-acetylcysteine was used as a sulphur donor to by-pass the cystathionine pathway, t…

Egalité entre les créanciers. Liquidation judiciaire, Clause pénale, Nullité ou pouvoir modérateur du juge ?

1991

International audience

Rat tyrosine kinase inhibitor shows sequence similarity to human α2-HS glycoprotein and bovine fetuin

1991

Human alpha 2-HS glycoprotein and bovine fetuin, abundant proteins of fetal plasma, are structural members of the fetuin family within the cystatin superfamily. They are characterized by the presence of two N-terminally located cystatin-like units and a unique C-terminal sequence segment not present in the other members of the cystatin superfamily. Search for related sequences revealed that the natural inhibitor of the insulin receptor tyrosine kinase [Auberger, Falquerho, Contreres, Pages, Le Cam, Rossi & Le Cam (1989) Cell (Cambridge, Mass.) 58, 631-640] shows sequence similarity to the mammalian fetuins. The sequence identity between rat tyrosine kinase inhibitor, human alpha 2-HS gl…

Créancier de l'art. 4O. Droit de poursuite individuelle, Liquidation judiciaire, Référé-provision, Condamnation du liquidateur au paiement immédiat d…

1991

International audience

Aldosterone biosynthesis induced by ACTH and angiotensin II in newborn rat adrenocortical cells transfected by c-EJ-Ha-ras oncogene

1991

Abstract Adrenocortical cells were obtained by fractionated trypsination of newborn rat adrenal glands and transfected with a plasmid containing the EJ T24 -Ha-ras oncogene. Isolation of adhesive cells led to a proliferative cell line with an overexpression of 21 kDa ras protein. These cells incubated with corticosterone or deoxycorticosterone as the precursor produced a high level of 18-hydroxycorticosterone and aldosterone as identified by gas chromatography- mass spectrometry. ACTH and angiotensin II increased the basal production of aldosterone nineteen-fold and six-fold respectively. Under ACTH stimulation the ratio between aldosterone and 18-hydroxycorticosterone production was 1:3. T…

New Reactions of Amino-Functionalized 3-Vinyl-1H-indoles and Tetrahydropyridin-4-yl Analogues with Dienophiles

1991

Reactions of 3-[2-(morpholin-4-yl)vinyl]-1H-indole (1), the 1,2-dihydro-9H-carbazole 2, as well as the 3-(tetrahydropyridin-4-yl)-1H-indoles 3a and 3b with some carbo- and heterodienophiles are described. The scope and limitations of the synthetic utility of these amino- (or homoamino)-functionalized 3-vinyl-1H-indoles are reported and some MO calculations for the qualitative prediction of their reactivities are presented. The reactions gave rise to substitution products, redox products, Diels-Alder adducts, ene adducts, and Michael-type adducts (Schemes 2 and 3).

Biological response of multicellular emt6 spheroids to exogenous lactate

1991

The influence of elevated lactate concentrations, as found in tumor microregions, on cellular growth, viability, and metabolic state was studied employing the multicellular spheroid model. Spheroids of EMT6/Ro cells were cultured at 37 degrees C in 5% or 20% (v/v) oxygen, using stirred media with various concentrations of exogenous lactate ranging from 0.0 mM (standard conditions) to 20.0 mM. Elevated concentrations of exogenous lactate led to a considerable decrease of the maximum spheroid diameter at growth saturation, e.g., for 20% O2 from around 1700 microns to 700 microns in 0.0 and 20.0 mM lactate respectively. Histological investigations showed that the thickness of the viable cell r…