showing 36 of ~574560 from 574555 documents
Physiological incongruity of the humero-ulnar joint: a functional principle of optimized stress distribution acting upon articulating surfaces?
1993
Investigations into the distribution of subchondral bone density in the human elbow have suggested that the geometry of the trochlear notch deviates from a perfect fit with the trochlea, and that the load is transmitted ventrally and dorsally rather than through the centre of the humero-ulnar joint. We therefore decided to make a quantitative assessment of the degree of incongruity between the two components in 15 human specimens (age distribution 60 to 93 years) with different types of joint surface. Polyether casts of the joint cavity were prepared under loads of 10, 40, 160 and 640 N. The thickness of the casts was then measured at 50 predetermined points, and an area distribution of the…
Iodine on a magnetized iron film evidence for a magnetic coupling
1993
Abstract Spin-resolved photoelectron spectra of iodine chemisorbed on a magnetized iron (110) surface have been taken using unpolarized VUV light. The partial spin spectra reveal the I 5p x and 5p z signals being split by up to 0.35 eV. This exchange splitting occurs due to hybridization of adsorbate and substrate bands as a consequence of the chemical bond of the halogen atoms to the iron surface.
Effects of amlodipine on renal haemodynamics in mild to moderate hypertensive patients. A randomized controlled study versus placebo.
1993
In this study the efficacy and safety of short-term amlodipine administration on renal haemodynamics were evaluated in mild to moderate hypertensive subjects. Our final goal was to evaluate whether the reduced blood pressure induced by treatment was associated with maintenance of renal function. After a run-in period with placebo, 30 hypertensive patients without cardiac or renal diseases were randomly allocated to a double-blind 4 weeks controlled study with amlodipine 10 mg once a day (15 patients) or placebo (15 patients). Renal haemodynamic measurements included effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) by radionuclide study using 131I-hippuran and 99mTc, w…
Chromatin structure of the yeast FBP1 gene: transcription-dependent changes in the regulatory and coding regions.
1993
We have studied the chromatin structure of the Saccharomyces cerevisiae FBP1 gene, which codes for fructose-1,6-bisphosphatase. A strong, constitutive, DNase I, micrococcal nuclease and S1 nuclease hypersensitive site is present close to the 3′ end of the coding region. In the repressed state, positioned nucleosomes exist around this site, and subtle changes occur in this nucleosomal organization upon derepression. A DNase I hypersensitive region is located within the promoter between positions −540 and −400 and it extends towards the gene in the derepressed state, leading to an alteration of nucleosomal positioning. Psoralen crosslinking of chromatin, which is used for the first time to st…
Is the selective information processing of food and body words specific to patients with eating disorders?
1993
The selective processing of food- and body size-related information was investigated using a modified version of the Stroop task. Anorexic and bulimic patients and matched female controls were compared on the basis of categorical (diagnosis), dimensional (restraint and drive for thinness) criteria, or both. The findings suggest that the phenomenon assessed by the Stroop paradigm is not exclusive to patients with a clinical eating disorder, but patients and those control subjects who are restrained eaters with a high drive for thinness share a selective processing of information related to shape and eating. The discussion focuses on the implications of these findings. © 1993 by lohn Wiley & …
Gamma-Ray and Radio Observations of PSR B1509-58
1993
Abstract : We report concurrent radio and gamma-ray observations of PSR B1509-58 carried out by the Parkes Radio Telescope and by the Burst and Transient Source Experiment (BATSE) and the Oriented Scintillation Spectrometer Experiment (OSSE) on the Compton Gamma Ray Observatory (CGRO-Gamma-ray light curves fitted at several energies between ~ 20-500 keV yield a phase offset with respect to the radio pulse that is independent of energy, with an average value 0.32 plus or minus 0.02. Although this value is larger by 0.07 than that reported by Kawai et al., the difference is not statistically significant (only~2 sigma) when account is taken of the uncertainty associated with their result. We b…
Solid-State Transition Mechanisms of Ammonium Nitrate Phases IV, III, and II Investigated by Simultaneous Raman Spectrometry and Differential Scannin…
1993
The solid-state transition mechanisms of ammonium nitrate IV, III, and II were studied by measuring samples simultaneously by Raman spectrometry and differential scanning calorimetry (DSC). The Raman instruments were a Fourier transform Raman spectrophotometer and triple monochromator Raman spectrophotometer with charge-coupled-device (CCD) detector. The spectral data of the transitions were collected simultaneously with the calorimetric data in the temperature-scanning mode of the calorimeter and then isothermally between transitions. The phase transition from phase IV to phase III occurred through an intermediate phase II*, whose lifetime was seven minutes maximum when the onset temperat…
Aspects of the characterization of cloverite by solid-state n.m.r. techniques
1993
Abstract Microporous gallophosphate cloverite has been studied by multinuclear ( 13 C, 19 F, 31 P, 71 Ga) solid-state n.m.r. spectroscopy. An extraordinarily strong quadrupolar coupling is shown to be the reason for a misleading line shape in 71 Ga MAS n.m.r. spectra. Using static 71 Ga n.m.r. spectroscopy, an estimate of the size of this quadrupolar coupling can be obtained. The limitations of the MAS technique for the study of quadrupolar nuclei in sites with very large quadrupolar couplings are addressed.
Compaction of tungsten oxide films by ion-beam irradiation
1993
Abstract Evaporated amorphous tungsten oxide films with low densities, deposited on different substrates, have been irradiated with various types of ions of different energies up to 30 MeV, and with fluences up to 10 18 cm −2 . Compaction of the films up to nearly the bulk density was observed. No changes of the stoichiometry as determined by various ion-beam analysis techniques were detectable. Raman measurements showed that ion-beam-modified films are also amorphous, but have a different microstructure from as-deposited films. The irradiated films have a higher refractive index than the as-deposited films. A low threshold for the compaction effect of a few times 10 12 ions cm −2 was found…
IgM and IgG antibodies to hepatitis C virus in patients with mixed cryoglobulinaemia
1993
SUMMARY To assess the relationship between hepatitis C virus (HCV) infection and essential mixed cryoglobulinaemia (EMC), sera from 23 patients with EMC were tested for IgG and IgM antibodies to HCV antigens and for HCV RNA. Quantitative HCV antibody studies were performed on scrum and purified cryoglobulin fractions. HCV antibodies of both IgG and IgM class were found in 22 (96%) patients. Ten of these were also HCV-RNA positives. Higher litres of anti-HCV IgM were present in the 11 patients with evidence of liver damage. Anti-HCV IgG antibodies were shown to be concentrated in the IgG fraction of cryoglobulins in all eight patients studied. These results strongly suggest a role for HCV in…
Inclusive eta photoproduction in nuclei.
1993
A local model for the nuclear medium modifications to the photoproduction of \ensuremath{\eta} mesons through the ${\mathit{N}}^{\mathrm{*}}$(1535) resonance is applied to the study of the inclusive reaction in medium and heavy nuclei. The use of effective Lagrangians and many body quantum theory allows one to incorporate the nuclear decay channels of the ${\mathit{N}}^{\mathrm{*}}$ involving a pair of nucleons and Fermi sea effects. Also the \ensuremath{\eta}N final state interaction is considered, taking into account the nuclear renormalization of the \ensuremath{\eta}N scattering cross section, and assuming a classical propagation between collisions. The results show a depletion and broa…
false
1993
The synthesis and the thermotropic phase behavior of the dipolar amphiphiles C 5 H 5 N + (CH 2 ) m OCOPhPHCOO(CH 2 ) m N + C 5 H 5 and the polymeric amphiphile [(CH 2 ) 6 OPhPhO(CH 2 ) 6 OCOCH([CH 2 ] 6 N + C 5 H 5 )COO] n are described
Sodium Chloride and Magnesium Chloride affected by Ripening of Camembert Cheese
1993
Ripening of cheese with three kinds of salt treatment was studied using MgCl 2 , NaCl or a mixture of the two. Proteolysis was followed by determination of TCA-soluble nitrogen and quantitative electrophoresis. A rapid one-step method for free fatty acids was used to determine short and long-chin fatty acids. In the presence of magnesium, proteolysis increased, even with NaCl, which seemed to delay the magnesium activation. Lipolysis was retarded by NaCl, which decreased the level of free fatty acids. An imbalance between proteolysis and lipolysis could be responsible for the unpleasant flavor of the cheese containing both MgCl 2 and NaCl
Lack of effect of oxytocin on the numbers of ?synaptic? ribbons, cyclic guanosine monophosphate and serotonin N-acetyltransferase activity in organ-c…
1993
In addition to the stimulating influence of the sympathetic system on the function of the mammalian pineal gland, neuropeptides such as neuropeptide Y, vasoactive intestinal polypeptide and arginine-vasopressin (AVP) are thought to function as modulators. Since AVP has been shown to influence pineal melatonin synthesis, the aim of the present study was to investigate the possible effects of the second hypothalamic nonapeptide oxytocin (OT), which likewise has been detected in the pineal gland. We therefore studied "synaptic" ribbon (SR) numbers, N-acetyltransferase (NAT) activity and the intracellular concentration of cyclic guanosine monophosphate (cGMP) following in vitro incubation of ra…
VEH electronic band structure of poly(phenylsilane)
1993
Abstract The electronic structure of all-trans syndiotactic and isotactic poly(phenylsilane) has been calculated using the valence effective Hamiltonian (VEH) method. The effects of attachment of the phenyl group on the electronic properties of polysilane are analysed in detail. The VEH results show a decrease of ionization potential and an increase of electron affinity which determine an important reduction of the bandgap. These features are correlated with σ−π and σ ∗ −π ∗ interactions between the silicon backbone and the phenyl group.
Electromagnetic scattering by a strip grating with nonplanar illumination
1993
An angular-spectrum method combined with the Galerkin procedure has been used to evaluate the electromagnetic scattering of a beam radiated by an aperture antenna after being incident obliquely upon a strip grating. Integral expressions for the transmitted and reflected fields are obtained. The incident beam radiated by the antenna is diffracted in several beams corresponding to the propagative Floquet harmonics. An angular shift of the transmitted and reflected fundamental harmonic beams has been shown. Comparison between numerical and experimental results validates this method. © 1993 John Wiley & Sons, Inc.
Initial experience of a new linear everting falloposcopy system in comparison with hysterosalpingography
1993
Objective To assess the endolumenal portion of the fallopian tube from ostium to fimbria using a specially designed linear everting catheter and microendoscope. The study compared falloposcopy results with those obtained with hysterosalpingography (HSG) in the same patients and explored the system's ability to classify internal tubal conditions. Design A prospective study of a new diagnostic technique, falloposcopy, versus conventional means of evaluating tubal status. Setting A tertiary university infertility center. Patients Eighteen infertile patients with a previous history of infertility of at least 2 years duration. Intervention Diagnostic falloposcopy was performed on a total of 31 t…
Calcitonin gene-related peptide-like immunoreactivity in spinal cord and superior cervical ganglion of the djungarian hamster (Phodopus sungorus)
1993
The indirect immunofluorescent method was employed to investigate the distribution of calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) in the spinal cord and superior cervical ganglion of the Djungarian hamster Phodopus sungorus. In cross-sections of the spinal cord, immunoreactive fibres and terminals were found in laminae 1 and 2 in high density, in the dorsolateral (Lissauer's) tract, in ventral and lateral horns, and in the area surrounding the central canal. A few CGRP-LI perikarya were seen in the ventral but not the dorsal horn. CGRP-LI was further observed in preganglionic sympathetic neurons which were labelled by retrograde axonal transport of fluoro-gold (FG) follo…
Bone Mineral Density and Long Term Exercise
1993
Evidence in human studies of the association of long term habitual exercise with bone mineral content (BMC) and density (BMD) largely comes from studies in athletes. In young adults, the highest BMC and BMD values have been found in strength and power-trained athletes, while endurance activities such as long distance running and swimming seem less effective with regard to peak bone density. Intensive endurance training may even be associated with amenorrhoea and decreased trabecular bone density in young females. However, after menopause female athletes show greater bone mass indicating that they do not share the accelerated decline in BMC observed in a nonathletic population. Middle-aged a…
Low frequency of cytotoxic liver-infiltrating T lymphocytes specific for endogenous processed surface and core proteins in chronic hepatitis B.
1993
To investigate the role of hepatitis B virus (HBV)-specific CD8+ T cells in chronic hepatitis B, the lytic activity of peripheral blood mononuclear cells (PBMC) and liver-infiltrating T cell clones and cytotoxic T cell (CTL) lines stimulated by recombinant vaccinia virus-infected cells were analyzed. Autologous and allogeneic Epstein-Barr virus-transformed B cells infected with vaccinia vectors (VAC) that contain sequences of the surface (S), secretory core (E), cytoplasmatic core (C) VAC antigen of HBV, or the wild-type (WT) VAC served as target cells. ELISA and immunoblotting showed HBV antigen expression in infected cells. Neither PBMC nor C- or E-VAC-stimulated CTL lines showed specific…
Beam phase measurement system for the K130 cyclotron in Jyväskylä
1993
Abstract A phase measurement system for Jyvaskyla new K = 130 heavy ion cyclotron has been designed and realized. The phase measurement is done using a set of capacitive probes to detect phase information from the internal ion beam. This data is vital for tuning purposes to obtain an isochronous magnetic field and to maximize the ion beam intensity.
A dammarane-type saponin from the roots of Ampelozizyphus amazonicus.
1993
A new C31 dammarane-type triterpenoid saponin has been isolated from the roots of Ampelozizyphus amazonicus. Its structure was elucidated to be ampelozigenin-15 alpha-O-acetyl- 3-O-alpha-L-rhamnopyranosyl-(1--2)-beta-D-glucopyranoside by 1D and 2D NMR spectroscopic methods, and by chemical transformations. Ampelozigenin is a novel triterpene, (20R,22R)-16 beta,22:16 alpha, 30-diepoxydammar-24(24')- methylene-3 beta, 15 alpha, 20-triol.
Studies on the solution behaviour of self-assembling polymeric systems
1993
Functional groups were attached to styrene-butadiene copolymers with different polymeric architectures and a low molecular weight compound. These polar stickers form binary, chelate-like contacts or extended juntion zones depending on their chemical nature. The solution properties of these amphiphilic species in toluene were studied by static light scattering.
Tumor oxygenation: a new predictive parameter in locally advanced cancer of the uterine cervix.
1993
Abstract Experimental evidence suggests that hypoxia may increase the malignant potential and reduce the sensitivity toward nonsurgical treatment modalities in solid rodent tumors. However, the importance of tumor hypoxia in human malignancies is still uncertain. We have developed a clinically applicable standardized procedure for the determination of intratumoral p O 2 in advanced cervical cancers by use of a computerized polarographic needle electrode histograph. To evaluate the significance of tumor oxygenation as a new oncologic parameter we initiated an open prospective clinical trial at the University of Mainz Medical Center in June 1989. Until October 1992 50 patients with advanced c…
VEH electronic structure of Si60
1993
Abstract We present a valence effective Hamiltonian (VEH) theoretical investigation on the electronic structure of Si60. The VEH one-electron energy level distribution calculated for Si60 is used to predict the ionization potential (7.86 eV), electron affinity (6.62 eV) and HOMO-LUMO energy gap (1.24 eV) of Si60. We also report the first allowed electronic transitions of Si60. The results are compared with other theoretical levels and with those calculated for C60.
Heated breathing tubes affect humidity output of circle absorber systems.
1993
Abstract Study Objective: To verify whether the airway climate in circle systems can be improved with heated breathing tubes. Design: Randomized, controlled, prospective clinical study. Setting: Operating theater of the Department of Maxillofacial Surgery. Patients: 26 adult patients undergoing prolonged anesthesia. Interventions: A total of 26 prolonged anesthetics were conducted in adult patients using a minimal fresh gas flow rate (0.6 L/min) and silicon breathing tubes (16 mm internal diameter) containing a heated coil. Group 1 ( n = 10 patients) was the control group; breathing tubes were unheated. In Group 2 ( n = 10 patients), breathing tubes were heated to 30°C. In Group 3 ( n = 6 p…
Natural killer and lymphokine-activated killer activity in HLA-B8,DR3-positive subjects.
1993
Abstract The haplotype HLA-B8,DR3 is over-represented in several autoimmune diseases, implying that genes predisposing people to these disorders are linked to this haplotype. In these diseases, various dysfunctions reflecting an impairment of the immune system have been found. Several reports indicate also that in HLA-B8,DR3-positive healthy subjects similar disorders may be demonstrated. In the present work, we have evaluated NK and LAK activity in these subjects. The study has been performed on monocyte-depleted peripheral blood MNCs by using the K-562 cell line as a target for NK activity and the HL-60 cell line for as a target LAK activity. LAK cells were obtained by incubating MNCs for…
Synthesis of Dienedioic and Tetraenedioic Acids by Oxidative Coupling of Unsaturated Carboxylic Acid Dienediolates by 1,2-Diiodoethane
1993
Abstract Acyclic and cyclic unsaturated carboxylic acids 1 to 4 are most easily converted to unsaturated dicarboxylic acids 5 to 8 by oxidative coupling of their diene- or triene-diolates by 1,2-diiodoethane. This procedure improves formerly reported oxidations by iodine or silver salts.
Semi-empirical MNDO study of the structure of some diorganotin (IV) glycylglycinates
1993
The geometrical structures of some diorganotin glycylglycinates have been obtained using the MNDO semi-empirical method. A good agreement with the experimental diffractometric data was found.
Nuclear fos domains in transcriptionally activated supraoptic nucleus neurons
1993
This study has analysed by light and electron microscopy immunolocalization the nuclear pattern of distribution of Fos-related proteins in supraotic neurons. Two experimental models of transcriptional activation have been used: sustained, global transcriptional activation, at relatively near physiological conditions, by six days of chronic intermittent salt loading; and superinduction of c-fos gene by this salt loading regime plus cycloheximide treatment for 4 h. In the first condition, the ultrastructural analysis showed a distribution of Fos-like immunoreactivity on the reticular network of dispersed chromatin that extends between the nucleolar surface and the nuclear envelope, whereas th…
Continuity and discontinuity of affective disorders and schizophrenia. Results of a controlled family study.
1993
Background: It is widely acknowledged that the genetic diatheses for schizophrenia and affective disorders are independent. However, there are increasing doubts about this classic view, and empirical evidence for a dichotomy of these two prototypes of functional psychoses is limited. A controlled family study of consecutive admissions was conducted to determine whether familial risks for schizophrenic (SCZ) and affective disorders were independent or overlapping. Methods: Index probands met Research Diagnostic Criteria for SCZ (n=146), schizoaffective (SA [n=115]), bipolar (BP [n=80]), or unipolar major depressive (UP [n=184])disorder. Comparison probands met Research Diagnostic Criteria fo…
Influence of intravenously administered lidocaine on cerebral blood flow in a baboon model standardized under controlled general anaesthesia using si…
1993
The baboon under general anaesthesia as a model to assess drug-induced cerebral blood flow changes (delta CBF) using single-photon emission tomography (SPET) offers great in vivo possibilities but has to comply with demands on control of anaesthesia-related influencing factors, such as PaCO2 changes. The model sought in this study and described here allows control of PaCO2, in the baboon under thiopentone anaesthesia by ventilation, and was evaluated for the functional dependence of delta CBF vs delta PaCO2, using SPET technetium-99m hexamethylpropylene amine oxime (HMPAO) and the split-dose method together with controlled ventilation. During the experiment the model was validated for norma…
Polymer-matrix route to (Bi, Pb)2Sr2Ca2Cu3O10+δ: The role of Ca2CuO3☆
1993
Abstract The use of polyethylenimine as active matrix agent has provided a fast synthesis method for (Bi, Pb)2Sr2Ca2Cu3O10+δ, starting from aqueous acetic solutions combined with careful control of the procedural variables. The 110 K phase is obtained as the only superconducting phase after sintering in air during 42 h at 860°C. This technique yields homogeneously sized, large (ca. 20 μm) platelets of the superconducting material. The presence of an excess of calcium and copper over the stoichiometric requirements accelerates the formation of the superconducting phase. This excess, which appears in the resulting material as Ca2CuO3, influences the superconducting properties, other than Tc, …
MR-tomographische Messung der diastolischen Relaxation hypertrophierter linker Ventrikel mit Single-slice-multi-phase-Technik
1993
In order to assess diastolic ventricular function in hypertensive patients, a single-slice multiphase sequence was used in order to measure contraction and early diastolic relaxation. There was no difference in the contraction velocity between hypertensives and normals (Vsys. n.r. = 56.1 +/- 13.8% LVDV/s vs. 51.7 +/- 8.6% LVEDV/s, stat, n. sign.). Early diastolic relaxation velocity in hypertensives was reduced as compared with the control group (Vdiast. 1n.r. = 37.9 +/- 13.1% LVEDV/s vs. 47.1 +/- 9.6% LVEDV/s, p < 0.05). There was no linear relation between abnormal relaxation and the extent of myocardial hypertrophy. Hypertensives with myocardial hypertrophy frequently had reduced early d…
Exact solution of ‘‘hot dimer’’ adsorption in one-dimensional lattices
1993
An analytical solution for the kinetics of the ``hot-dimer'' adsorption in a one-dimensional lattice is reported. Hot dimers are molecules that dissociate after deposition, and each of the remaining monomers fly apart up to a maximum distance R from the original adsorption sites. The kinetics of this process is strongly dependent on the flying distance R. We find a particular behavior of the jamming coverage as a function of R. Monte Carlo simulation results are in agreement with such a calculation.
Amyloidoma of the gasserian ganglion as a cause of symptomatic neuralgia of the trigeminal nerve: report of three cases.
1993
Three cases of symptomatic neuralgia of the trigeminal nerve due to an amyloidoma in the gasserian ganglion are described. The correct diagnosis was not made prior to histological examination of the surgical biopsy specimens. Medical history and clinical observation led to the diagnosis of a malignant process of the nasal cavities in the first patient; of an inflammatory dental focus in the second patient; and of multiple sclerosis in the third patient. CT findings were normal in cases 1 and 2; in case 3, a schwannoma was suspected from the CT appearances. In case 1, MRI had not been performed; in cases 2 and 3, MRI revealed a tumour mass which was also considered to be a schwannoma. Histol…