showing 36 of ~574560 from 574555 documents
Morbid risks for major disorders and frequencies of personality disorders among spouses of psychiatric inpatients and controls
1993
Three hundred fifty-three psychiatric inpatients and their 192 living spouses and 98 control subjects and their 54 living spouses were examined and interviewed for affective, schizoaffective, schizophrenic (Research Diagnostic Criteria [RDC]), and personality disorders (DSM-III-R) using the Lifetime Version of the Schedule for Affective Disorders and Schizophrenia (SADS-L) and the Structured Clinical Interview for DSM-III-Personality Disorders (SCID). The morbid risks of spouses for unipolar depression were between .15 and .25, and those for other major disorders were below .03. The morbid risks of spouses of bipolar patients for unipolar depression exceeded those of other spouses by 50% wi…
Synthesis of oligodeoxynucleotides containing diastereomeric dihydrodiol epoxide-N6-deoxyadenosine adducts of polycyclic aromatic hydrocarbons
1993
Abstract A generally applicable route is reported for the synthesis of oligodeoxynucleotides which contain structurally defined N 6 -deoxyadenosine adducts, derived from sterically highly hindered dihydrodiol epoxides of polycyclic aromatic hydrocarbons (PAH).
Thermal stability of poly(styrene-b-methyl methacrylate) and poly(styrene-b-ethylene-co-1-butene-b-methyl methacrylate)
1993
The thermal stability of poly(styrene-b-methyl methacrylate) diblock copolymers (= P(S-b-MMA)) and poly(styrene-b-ethylene-co-1-butene-b-methyl methacrylate) triblock copolymers (=P(S-b-EB-b-MMA)) was investigated. Well-defined high molecular weight block copolymers with narrow molecular weight distribution (MWD) were molded at different temperatures in vacuum and the alteration of the MWD was sensitively monitored by gel permeation chromatography (GPC). Up to 240°C P(S-b-MMA) shows almost no broadening of the MWD. At higher temperatures low molecular weight polystyrene-rich portions are formed. The number average molecular weight (Mn) is strongly reduced. P(S-b-EB-b-MMA) triblock copolymer…
Phosphorescence emission and polarization of quinoline 3-carbonitrile
1993
Abstract The phosphorescence emission and excitation spectra and their polarization have been studied for quinoline 3-carbonitrile in methylcyclohexane and ethanol glasses at 77 K. From the results obtained in this molecule (τ=1.15 sec in ethanol, τ=1.04 sec in methylcyclohexane and out-of-plane polarization) it is concluded that the emission is orginated from a triplet state of 3 ππ * character. The two major spin-orbit coupling mechanisms through which the ππ * state of quinoline 3-carbonitrile acquires dipole-allowed character via nπ * states are: 1. In ethanol glass: 2. In methylcyclohexane glass:
Role of leuprolide acetate depot in hysteroscopic surgery: a controlled study.
1993
Objective To evaluate leuprolide acetate (LA) depot (Enantone Depot, Takeda, Italy) when administered preoperatively in hysteroscopic surgery. Design Prospective, comparative study. Setting University Clinic of Obstetrics and Gynecology. Patients One hundred ninety-three patients (114 pretreated with LA depot and 79 controls) who underwent hysteroscopic surgery for uterine septa (group A), submucous fibroids (group B), and abnormal uterine bleeding (group C). Results In groups B and C there was a significant reduction in the operating time, bleeding during the operation, and the amount of distention medium required after LA depot administration, but no significant differences in surgical fe…
Structural transitions and melting of copper clusters
1993
Molecular dynamics is used to study the melting and structural transitions of small copper clusters. The melting temperature is found to be proportional to the average coordination number. Small icosahedral clusters melt at slightly higher temperatures than the cubic structures. Small cuboctahedral clusters are not stable but transform via a nondiffusive transition to icosahedral structure.
Sister chromatid exchange in Waldenström's macroglobulinemia
1993
Results on sister chromatid exchange (SCE) frequency and interchromosomal distribution in bone marrow and peripheral blood cultures from patients with Waldenström's macroglobulinemia are reported. PHA-stimulated bone marrow cultures showed increased SCE frequencies in all 12 patients examined. The increase was particularly high in two cases (17.07 and 16.77 SCE/cell, respectively) and, in one of them, a very high SCE level was found in PHA-stimulated peripheral blood culture (40.81 SCE/cell). In LPS-stimulated cultures, increased SCE levels were observed in some patients. Comparison between SCE frequency in bone marrow cell cultures with either mitogen showed a significant increase in PHA-s…
Die kombinierte operative und radiotherapeutische Behandlung (CORT) von Beckenwandrezidiven: Erfahrungsbericht nach 3 Jahren
1993
CORT has been developed to treat recurrent gynaecological malignancies infiltrating the pelvic wall unilaterally. The surgical part consists of: (i) staging laparotomy/lymphadenectomy, (ii) maximum tumour resection at the pelvic wall and exenteration of infiltrated central pelvic organs, (iii) implantation of guiding tubes on the residual tumour/tumour bed on the pelvic wall, (iv) pelvic wall plasty with muscle, musculocutaneous and omentum flaps, (v) operative reconstruction of bowel, bladder and perineo-vulvo-vaginal functions. Radiation is performed as interstitial high dose rate brachytherapy through the implanted tubes. Patients without prior pelvic irradiation receive in addition, who…
Effet colloide-protecteur d'extraits de parois de levures sur la stabilité tartrique d'une solution hydro-alcoolique modèle
1993
<p style="text-align: justify;">L'effet colloïde-protecteur d'extraits mannoprotéiques de parois de levures vis-à-vis de la précipitation tartrique a été étudié en solution hydroalcoolique, en utilisant un IST mètre (Indice de Stabilité Tartrique).</p><p style="text-align: justify;">Nous avons montré que les deux extraits levuriens inhibaient la cristallisation du bitartrate de potassium au même titre que l'acide métatartrique et la carboxyméthylcellulose, mais à un niveau plus faible. Le niveau de stabilité retenu (ISTC-75) est assuré avec des concentrations par litre de 7,5 mg d'acide métatartrique et de 18 mg de carboxyméthylcellulose. Des concentrations en extraits man…
Cortical astrocytosis in juvenile rhesus monkeys infected with simian immunodeficiency virus
1993
The pattern of expression of GFAP immunoreactivity in astrocytes of the juvenile rhesus monkey cortex was examined following infection with simian immunodeficiency virus (SIV). Blocks of cerebral cortex plus subjacent white matter from saline- and formalin-perfused brain were examined by peroxidase-linked immunochemical and immunofluorescence staining of deparaffinized sections. Strong GFAP immunoreactivity was found in astrocytic cells in both uninfected and SIV-infected juvenile macaque in the subpial cerebral cortex and in subcortical white matter, where GFAP-positive cells were abundant. GFAP staining of cortical layers 2-6 on the other hand was weak or absent in three uninfected contro…
INTERACTIONS OF ORGANOTIN(IV) HALIDES WITH REDUCED GLUTATHIONE IN AQUEOUS-SOLUTION
1993
Abstract Glutathione (GSH) is a compound extremely common among many living organisms in which it plays a fundamental role in the processes of detoxification. Also, organotin(IV) derivatives are more and more commonly used in technological processes or as antitumor drugs. So it seemed interesting to investigate the possible interactions between GSH and organotin compounds in water. Particularly, it has been studied because of its role in the organic radicals linked to the tin center on the stoichiometry and the structure of the adducts. Information was obtained following the reaction between Me n SnCl 4-n (n = 1 to 3) and GSH by Mossbauer and NMR spectroscopies on the assumption that change…
Characterization of antigenic epitopes of potato virus Y.
1993
Immunochemical analysis of overlapping synthetic hexapeptides covering the entire length of the coat protein of potato virus Y (PVY) revealed immunodominant regions both at the N-terminal and at the C-terminal end of the coat protein. Immunization of rabbits with synthetic peptides representing N- and C-terminal regions of the coat protein resulted in production of antibodies that reacted with PVY. Antigenicity of PVY peptides was found to correlate with predicted beta turns, with hydrophilicity and with predicted chain flexibility. Characterization of the immunochemical properties of PVY will facilitate the development of detection methods for potyviruses.
Shell structure and level spacing distribution in metallic clusters
1993
The lattice gas Monte Carlo and tight binding method is used to study the electronic shell structure in large metallic clusters. The average density of states of a large ensemble of deformed clusters shows the same shell structure as the most spherical geometry. The level spacing distribution at the Fermi level is a Wigner distribution.
The influence of lorazepam medication upon the transfer properties of the brain during sleep in man
1993
In order to get better insight into the principles of information processing by the brain during sleep and its alterations under the influence of drugs we applied some tools from linear system theory to sleep EEG data. We investigated late components of auditory and visually evoked potentials (AEPs and VEPs) during different sleep stages and calculated from these the so-called amplitude-frequency characteristics (AFC). The main advantage of this analysis is that it enables one to detect functional differences during different sleep stages. This information can hardly be obtained by conventional spectral analysis. The result of our investigation was that the transfer properties of the brain …
On the Conditions to Prevent Plastic Shakedown of Structures: Part II—The Plastic Shakedown Limit Load
1993
Following the results of a companion paper, the concept of plastic shakedown limit load is introduced for an elastic-perfectly plastic material structure subjected to combined cyclic (mechanical and/or kinematical) loads and steady (mechanical) load. Static and kinematic approaches are available for the computation of this load, in perfect analogy with the classic (elastic) shakedown limit load. The plastic shakedown limit state of the structure being in an impending alternating plasticity collapse is studied and a number of interesting features of it are pointed out.
Pepstatins: Aspartic proteinase inhibitors having potential therapeutic applications
1993
Cathepsin D (EC 3.4.23.5) is a lysomal aspartie proteinase that is involved, under normal phusiologycal conditions, ...
Transport of dipeptides and phosphono dipeptides through an immobilized liquid membrane. Stereoselectivity of the process
1993
Abstract Dipeptide and phosphono dipeptide hydrochlorides permeated well through a 1-decanol membrane supported in a porous polyethylene hollow fiber matrix. This transfer is easily accomplished either by passive or by carrier-facilitated (with Kryptofixes 222 or 5 present in the membrane phase) transport. The transport is stereoselective with l-l dipeptides being transported faster than their l-d isomers.
Dipole surface plasmon in large K N + clusters
1993
The dipole surface plasmon forK N + clusters is analyzed using the RPA sum-rule technique within a semiclassical Density Functional Theory and the spherical jellium model. The theoretical frequencies are blue shifted as compared to the experimental ones. The discrepancies between theory and experiment are reduced when considering non-local energy contributions in the density functional and phenomenologically including atomic lattice effects by means of an electron effective mass and a static dielectric constant.
A theoretical approach to pionic atoms and the problem of anomalies
1993
Abstract We have constructed a theoretical optical potential for pionic atoms based on the first- and second-order terms of a many-body expansion on the number of ph excitations. The p-wave parts are very much influenced by the medium polarization. The quenching at large densities produced by this phenomenon, together with the one from the Lorentz-Lorenz effect, and modifications over standard potentials due to the isospin dependence, lead to a new potential which produces notoriously improved results in the problem of anomalies. A clearer definition of this problem is proposed as the inability of standard potentials to reproduce simultaneously the data for light and heavy nuclei. Finally a…
Effect of starvation on haemolymph vitellogenins and ovary uptake in Spilostethus pandurus
1993
Abstract 1. 1. Starvation reduces haemolymph vitellogenins and their incorporation by developing oocytes in S. pandurus adult females. 2. 2. Access to food restores unspecifically the protein levels in both haemolymph and ovaries. 3. 3. Topical treatments with JH promote de novo specific synthesis of vitellogenins and incorporation by the ovaries. 4. 4. These results point to a strong role of the JH as the regulatory factor of both reproductive phenomena in S. pandurus .
Competing proton and neutron alignments in 117−120Xe
1993
The role of water in hemoglobin function and stability
1993
Masses, mixings, Yukawa couplings and their symmetries
1993
We present a method to find the number of real and imaginary observable parameters coming from the Yukawa sector in an arbitrary gauge theory. The method leads naturally to a classification of Yukawa couplings according to their symmetries and suggests a new parametrization of masses and mixings that is useful to study the behaviour of Yukawa couplings under the renormalization group. We apply it to some examples based on the Standard Model with Yukawa couplings obeying various chiral symmetries. We also show how our method of parameter counting can be used in some models with an enlarged leptonic sector.
A Monte Carlo Study of the Low-Temperature Properties of Strongly Correlated Localized Particles in Disordered Systems
1993
A computer simulation method is presented, which yields the ground state as well as the low-energy excitations for disordered systems of many interacting particles. The efficiency of the method is demonstrated by the application to the Coulomb glass, i.e. many localized electrons with long-range interaction. The obtained knowledge about the specific configurations of a large number of excited states is only the starting point for further investigations. First results are presented which shed a new light on old controversies about the behaviour of correlated electrons within the Coulomb gap regime.
Towards an accurate molecular orbital theory for excited states : Ethene, butadiene, and hexatriene
1993
A newly proposed quantum chemical approach for ab initio calculations of electronic spectra of molecular systems is applied to the molecules ethene, trans‐1,3‐butadiene, and trans‐trans‐1,3,5‐hexatriene. The method has the aim of being accurate to better than 0.5 eV for excitation energies and is expected to provide structural and physical data for the excited states with good reliability. The approach is based on the complete active space (CAS) SCF method, which gives a proper description of the major features in the electronic structure of the excited state, independent of its complexity, accounts for all near degeneracy effects, and includes full orbital relaxation. Remaining dynamic ele…
General-relativistic approach to the nonlinear evolution of collisionless matter.
1993
A new general-relativistic algorithm is developed to study the nonlinear evolution of scalar (density) perturbations of an irrotational collisionless fluid up to shell crossing, under the approximation of neglecting the interaction with tensor (gravitational-wave) perturbations. The dynamics of each fluid element is separately followed in its own inertial rest frame by a system of twelve coupled first-order ordinary differential equations, which can be further reduced to six under very general conditions. Initial conditions are obtained in a cosmological framework, from linear theory, in terms of a single gauge-invariant potential. Physical observables, which are expressed in the Lagrangian…
Residual fluctuations in the microwave background at large angular scales: Revision of the Sachs-Wolfe effect
1993
In this paper we revise the Sachs-Wolfe (SW) computation of large-scale an isotropies of the microwave background temperature, taking into account the properties of the metrics admitting an isotropic distribution of collisionless photons. We show that the metric used by SW belongs to the aforementioned class, and conclude that the microwave background (once the dipolar anisotropy has been subtracted) should now be isotropic at large angular scales, provided that it was isotropic on the last scattering surface and assuming that the growing mode of a pressureless Einstein-de Sitter perturbation is a good description of the metric.
Histone deacetylase A key enzyme for the binding of regulatory proteins to chromatin
1993
AbstractCore histones can be modified by reversible, posttranslational acetylation of specific lysine residues within the N-terminal protein domains. The dynamic equilibrium of acetylation is maintained by two enzyme activities, histone acetyltransferase and histone deacetylase. Recent data on histone deacetylases and on anionic motifs in chromatin- or DNA-binding regulatory proteins (e.g. transcription factors, nuclear proto-oncogenes) are summarized and united into a hypothesis which attributes a key function to histone deacetylation for the binding of regulatory proteins to chromatin by a transient, specific local increase of the positive charge in the N-terminal domains of nucleosomal c…
(o-Hydroxyphenyl)methylphosphonic acids: Synthesis and potentiometric determinations of their pKaValues
1993
(o-Hydroxyphenyl)methylphosphonic acids are readily obtained from o-(bromomethyl)- or o-(hydroxymethyl)phenols and trialkyl phosphites. Subsequent hydrolysis leads to the corresponding phosphonic acids. For a series of such compounds, the pKa values have been determined by potentiometry. Their dependence on additional substituents in the aromatic ring is discussed in terms of electronic and steric effects.
Production of wine extracts for chemical and sensory analysis with an odour representative of that of the original wine
1993
National audience
Use of extract dilution sniffing analysis for the detection of flavor impact components in wine from falanghina grapes
1993
National audience
Role of calcium in the adhesion and fusion of bilayers.
1993
The interaction forces and fusion mechanisms of mixed zwitterionic-anionic phospholipid bilayers were measured with the surface forces apparatus. The bilayers were 3:1 mixtures of either dimyristoylphosphatidylcholine and dimyristoylphosphatidylglycerol (DMPC/DMPG) or dilauroylphosphatidylcholine and dilauroylphosphatidylglycerol (DLPC/DLPG), and experiments were carried out in NaCl solutions with and without CaCl2. In NaCl solutions, the forces between either mixed bilayer system were consistent with the DLVO (Derjaguin-Landau-Verwey-Overbeek) theory of repulsive electrostatic and attractive van der Waals forces, and fusion did not occur. At high pH (> 6) and in high (20 mM) NaCl concentra…
Atomic beam magnetic resonance apparatus for systematic measurement of hyperfine structure anomalies (Bohr-Weisskopf effect)
1993
Abstract An atomic beam magnetic resonance (ABMR) apparatus has been constructed at Orsay, and has been installed at the CERN PS Booster ISOLDE mass separator facility for “on-line” work with radioactive isotopes in a program to measure hyperfine structure anomalies (the Bohr-Weisskopf effect) over long isotopic chains. The hfs anomalies result from the effect of the spatial distribution of the nuclear magnetization on the atomic hfs interaction. Constructional details of the system are described: emphasis is placed on the measurement of nuclear g-factors by a triple resonance, laser state selected, ABMR method. A precision better than 10−4 for gI values has been obtained in stable atomic b…
Influence of chirality on the structure of phospholipid monolayers.
1993
Restoration of the Zisa Palace, Palermo
1993
The building of the Zisa, commissioned by William I, began in 1164-1165; it was completed by William II in the years immediately following. It was built as a splendid place for rest and amusement, ...