showing 36 of ~574560 from 574555 documents
C-reactive protein in boutonneuse fever
1986
European vestibular experiments on the Spacelab-1 mission: 4. Thresholds of perception of whole-body linear oscillation.
1986
Thresholds for the detection of linear oscillatory motion at 0.3 Hz in the X, Y and Z body axes were determined during the flight of Spacelab-1 and on the ground pre- and post-flight, using the method of limits with a single staircase procedure. Pre-flight, Z axis thresholds (mean 0.077 ms-2) were significantly higher than X and Y thresholds (mean 0.029 ms-2). Measures obtained on three crew members in-flight exhibited thresholds greater, by a factor of 1.5-4.3, than those obtained pre-flight. Post-flight, two crew members had significantly elevated X and Y axis thresholds whereas the other two crew members had lowered thresholds in X, Y and Z axes. In general, thresholds had returned to pr…
Physico-chemical characterization of polyethylenes obtained in the presence of different catalysts containing alkoxyligands
1986
The effect of the kind and number of alkoxy ligands (OR) in organometallic Ti-Al catalyst on the properties of polyethylenes obtained i.e. molecular weight, mechanical and rheological properties, density, crystallinity, melting point, heat of fusion and number of chain branches was studied. Polyethylene obtained over Ti-Al catalyst with OR ligands has particularly high molecular weight, high density, better mechanical properties, higher resistance to heat, different rheological characteristics and lower number ot chain branches in comparison with standard HDPE. It is possible to control the polyethylene synthesis process and to obtain the polymer of required properties by selecting the OR …
IONIC TRANSPORT ACROSS POROUS CHARGED MEMBRANES AND THE GOLDMAN CONSTANT FIELD ASSUMPTION
1986
Starting from a simple theoretical model based on Nernst-Planck flux equations and the Donnan equilibrium relationship, the ionic transport across a porous, charged membrane is analysed and conditions are given which make exact the so-called “constant field assumption”. The validity of the reported results is later verified in the case of a well-known problem: the ionic transport across a cation-exchange membrane under bi-ionic conditions.
Pathogenic factors in recurrent urinary tract infections and renal scar formation in children
1986
Method of analytic continuation by duality in QCD: Beyond QCD sum rules
1986
We present the method of analytic continuation by duality which allows the approximate continuation of QCD amplitudes to small values of the momentum variables where direct perturbative calculations are not possible. This allows a substantial extension of the domain of applications of hadronic QCD phenomenology. The method is illustrated by a simple example which shows its essential features.
The effects of short pulses of light at night on numbers of pineal "synaptic" ribbons and serotonin N-acetyltransferase activity in male Sprague-Dawl…
1986
To characterize further the functionally enigmatic "synaptic" ribbons (SR) of the mammalian pineal gland and to study possible relationships to melatonin synthesis, in the present investigation rats were exposed to short pulses of light at night when both SR numbers and serotonin N-acetyltransferase (NAT) activity are high in comparison to day-time values. Male Sprague-Dawley rats were killed at 13:00 and 01:00 h, respectively, and at 01:10 and 02:00 h after exposure to light for 10 and 60 min, respectively. The pineals were rapidly taken out and cut sagittally in half. One half was processed for electron-microscopic quantitation of SR numbers and the other half for NAT determinations. It w…
Ciclosporin and prednisone v. prednisone in treatment of Graves' ophthalmopathy: a controlled, randomized and prospective study.
1986
Forty patients with Graves' ophthalmopathy stages III-V were divided into two groups in a random manner according to their year of birth. Group I received prednisone in decreasing dosage. Group II received prednisone at a comparable dosage and ciclosporin. Steroids were discontinued after 10 weeks in the two groups. In the patients of group II, ciclosporin was continued over 12 months. The therapeutic effect was assessed by an activity score based on subjective and objective symptoms (computerized tomography and sonography of the orbit, Hertel values, clinical findings). All signs of endocrine ophthalmopathy improved significantly in both groups (P less than 0.01 in group I; P less than 0.0…
The reaction at Eγ = 60 and 80 MeV
1986
Abstract The tagged photon technique has been used to measure the 12C photoproton cross section over the angular range θp = 30°–135° for Eγ = 60 and 80 MeV. Comparison of the results with quasifree knockout and quasideuteron calculations shows that photon interaction with two-nucleon pairs is dominant at least for high excitation energies in the residual nucleus.
Ein neues Verfahren zur Ausmessung der Schublade in der gehaltenen seitlichen Aufnahme des oberen Sprunggelenkes
1986
Fur die Auswertung der gehaltenen Aufnahme des oberen Sprunggelenkes im seitlichen Strahlengang werden im Schrifttum unterschiedliche Methoden angegeben. Es wird ein Mesverfahren vorgestellt, das einfache Anwendbarkeit, Berucksichtigung individueller Knochenmase und ausreichende Fehlersicherheit in sich vereinigt.. Aus 50 Rontgenbildern unverletzter Sprunggelenke wurden Normal-, Grenz- und pathologischer Bereich ermittelt und die Methode mit der meist ublichen Messung einer posterioren tibio-talaren Distanz verglichen. Fur das neue Verfahren wurde hier eine genauere Differenzierungsmoglichkeit gefunden. Als zusatzlicher Vorteil wird die Moglichkeit angesehen, auch Aufnahmen mit fehlerhafter…
CONSUMPTION DECISIONS WITH INCOME UNCERTAINTY AND A KINKED BUDGET CONSTRAINT
1986
Muscle adenylate kinase in Duchenne muscular dystrophy
1986
Abstract On the basis of electrophoretic and enzyme inhibition studies it was postulated that an aberrant adenylate kinase occurs in muscle and serum of patients with Duchenne muscular dystrophy (Schirmer, R.H. and Thuma, E. (1972) Biochim. Biophys. Acta 268, 92–97; Hamada, M. et al. (1981) Biochim. Biophys. Acta 660, 227–237; Hamada et al. (1985) J. Biol. Chem. 260, 11595–11602. On the basis of the following results we conclude that Duchenne muscular dystrophy patients do not possess an unusual adenylate kinase isoenzyme. (1) In muscle biopsies from five Duchenne patients, the electrophoretic mobility of adenylate kinase and the inhibition of the enzyme by P 1 , P 5 -di(adenosine-5′)pentap…
Dynamic nuclear polarisation of biological matter
1986
Polarised targets as used in high energy physics experiments may be of considerable interest in biological structure research using polarized neutrons. So far, this promising method has been facing difficulties in getting reasonable polarization of the target nuclei. We report on a polarized "frozen spin" target which has been prepared from an enzyme dissolved in a mixture of heavy water and deuterated propanediol doped with a completely deuterated paramagnetic radical. Clusters of 700 protons defined by the structure of lysozyme embedded in a fully deuterated matrix were polarized to 75% within an hour by 4 mm microwave irradiation in a magnetic field of 2.5 tesla at a temperature of 0.3 K…
Activities of some peptidases and proteinases in germinating kidney bean, Phaseolus vulgaris
1986
The activities of aminopeptidase (EC 3.4.11), dipeptidase (EC 3.4.13), carboxypeptidase (EC 3.4.16), naphthylamidase (EC 3.4.11) and proteinases (EC 3.4.21) were assayed in extracts from the cotyledons and the axial tissues of resting and germinating kidney beans (Phaseolus vulgaris L. cv. Processor). The activities of the alkaline peptidases (aminopeptidase hydrolyzing Leu-Tyr at pH 9.2 and dipeptidase acting on Ala-Gly at pH 8.5) and naphthylamidases (hydrolyzing Leu-β-naphthylamide at pH 6.4) were high in the cotyledons of resting seeds, but decreased during germination. This decrease was faster than the loss of the total nitrogen. On the contrary, the activities of carboxypeptidase (hyd…
On the convergent parts of high order spectral moments of stationary structural responses
1986
The paper deals with the evaluation of the convergent parts of the high spectral moments of linear systems subjected to stationary random input. An adequate physical meaning of these quantities in both the time and frequency domains is presented. Recurrence formulas to obtain the high convergent cross spectral moments of any order are given in the case of white noise input.
Antagonist discrimination between subtypes of tachykinin receptors in the guinea-pig ileum.
1986
1. The effects of substance P and eledoisin on spontaneous and electrically-evoked release of [3H]acetylcholine, and on smooth muscle were studied in the guineapig myenteric plexus-longitudinal muscle preparation preloaded with [3H]choline. Substance P and eledoisin caused transient increases in spontaneous release of [3H]acetylcholine and in longitudinal muscle tone. Both tachykinins were equipotent in contracting the muscle, but eledoisin was more potent than substance P in eliciting [3H]acetylcholine release. The release caused by substance P was enhanced in the presence of naloxone and scopolamine which suggests that the release is modulated through opioid and muscarinic receptors. 2. S…
Untersuchungen zur Eiproduktion beim Zebrabärbling (Brachydanio rerio, Ham.-Buch.)
1986
Zusammenfassung Die Untersuchungen zur Eiprodukcion beim Zebrabarbling zeigen, das in der Zahl der abgelegten Eier erhebliche mdividuelle Unterschiede bestehen. Die Gruppengrose hat im Bereich von 2 Weibchen und 4 Mannchen bis 8 Weibchen und 16 Mannchen keinen Einflus auf die Eizahl, die zwischen 40 und 100 Eier je Weibchen und Tag schwanken kann. Die Eiablage erfolgt in einem Zyklus von zwei Tagen. Eine Trennung der Geschlechter beeinflust sowohl die Zahl als auch die Qualitat der abgelegten Eier. Verwendet man die Eizahl als Parameter in einem Reproduktionstest, dann mus die Gesamteizahl, die Zahl der im Korper denaturierten und die Zahl der unbefruchteten Eier erfast werden. Summary Egg …
Effects of sulphonylureas on spontaneous motility and induced contractions in rat isolated uterus
1986
Abstract To clarify the action of sulphonylureas on calcium, the effect of tolbutamide and ghbenclamide has been investigated on a Ca-dependent process, the contractile activity of uterine smooth muscle. Both sulphonylureas antagonized the contractions evoked by CaCl2 in a non-competitive manner when the uterus was maintained in depolarizing solution and did not affect the spontaneous contractions of rat uterus. The capacity of tolbutamide and ghbenclamide to relax vanadate-induced contraction of rat uterus in Ca-free medium suggests that sulphonylureas may have an intracellular site of action related to cytosolic free Ca levels, or effect a reduction in Ca action.
Studies of alumina as a support of titanium catalyst for low-pressure ethylene polymerization
1986
The effect of alumina treatment with aqueous solutions of hydrochloric acid and ammonium fluoride as well as temperature of its calcination on the activity of Al-Ti/Al2O3 supported organometallic catalyst for ethylene polymerization has been studied. The dependence between the specific surface area of the support and both the kind and concentration of the modifying agent, concentration of OH-groups on Its surface and concentration of active centres with various activities is discussed with reference to the activity of the supported Al-Ti/Al2O3 catalyst. It was demonstrated that there is no simple relationship between the concentration of OH-groups on the support and the activity of the Ti-…
Temporal aspects of the O-glycosylation of Saccharomyces cerevisiae mannoproteins
1986
Abstract Cleavage of the O-glycosyl bonds of Saccharomyces cerevisiae cell wall mannoproteins by β-elimination resulted in the release of about 8% of the carbohydrate in the form of mannose and other low molecular weight oligomannosaccharides (mannose to mannopentaose), leaving 92% mannose still covalently linked to the peptide, and suggesting that this alkali-resistant fraction was N-glycosidically linked. At the non-permissive temperature, S. cerevisiae sec mutants accumulated in the cytoplasm mannoproteins with different degrees of O- and N-glycosylation. The glycoproteins of mutant sec 20-1 contained 60% of the carbohydrate linked by N-bonds, the remainder being O-glycosidically linked.…
Spin glasses: Experimental facts, theoretical concepts, and open questions
1986
This review summarizes recent developments in the theory of spin glasses, as well as pertinent experimental data. The most characteristic properties of spin glass systems are described, and related phenomena in other glassy systems (dielectric and orientational glasses) are mentioned. The Edwards-Anderson model of spin glasses and its treatment within the replica method and mean-field theory are outlined, and concepts such as "frustration," "broken replica symmetry," "broken ergodicity," etc., are discussed. The dynamic approach to describing the spin glass transition is emphasized. Monte Carlo simulations of spin glasses and the insight gained by them are described. Other topics discussed …
Human corticotropin-releasing factor (hCRF) is a potent respiratory analeptic. Physiological and clinical aspects.
1986
During intravenous corticotropin-releasing factor stimulation tests we observed a deepening of the tidal volume in 35 patients. To investigate this presumed respiratory stimulation we measured respiratory parameters in 12 healthy male volunteers in a single-blind placebo-controlled trial. The intravenous 60-s infusion of 100 micrograms of human corticotropin-releasing factor induced a very potent respiratory stimulation in every subject: respiratory minute volume (mean +/- S.D.) increased by 81% from 6.319 +/- 0.577 to 11.464 +/- 1.264 liters per min (P less than 0.001), whereas there was only a slight rise in the mean respiratory rate from 12.4 +/- 3.0 to 14.7 +/- 2.7 breaths per min (P le…
European vestibular experiments on the Spacelab-1 mission: 1. Overview.
1986
During the flight of Spacelab-1 a series of vestibular experiments was performed on the crew by a group of European investigators. Control experiments were carried out on the same subjects pre- and postflight. The tests included caloric stimulation of the ears, threshold measurements of response to linear acceleration, motion sickness provocative stimuli, vestibulo-ocular reflexes during linear and angular stimulation, estimation of the subjective vertical (luminous line measurements) and static ocular counterrotation at various tilt angles. The caloric experiment proved the existence of a nonthermoconvective mechanism of caloric nystagmus in space. Most of the other test results point to a…
In vitro effects of estradiol, testosterone, and progesterone on 5-methoxyindole content, cyclic adenosine 3',5'-monophosphate synthesis, and norepin…
1986
To examine the effects of estradiol, testosterone, or progesterone on cyclic adenosine 3',5'-monophosphate (AMP) accumulation, 5-methoxyindole levels, and norepinephrine (NE) release by the female guinea pig pineal complex, samples of the deep, intermediate, or superficial portions of the complex were incubated in vitro with varied concentrations of either hormone. Exposure for 10 minutes to physiological amounts of estradiol (10 nM) or to 100 microM NE increased significantly cyclic AMP levels to the same extent in the three pineal regions. A maximal effect on cyclic AMP accumulation was observed at 100-nM concentrations of estradiol, with a tendency to return to basal levels at 1-10 micro…
Phytoplankton structure in different lake types in central Finland
1986
Phyloplankton structure and its relation to physical and chemical properties of the water was studied in 58 central Finnish lakes. The biomass ranged from 0.2 to 14.2 g m−3 and the number of taxa per sample ranged from 33 to 152. The lakes were grouped into 5 types according to their trophic state: eutrophic, dyseutrophic, mesotrophic, oligotrophic, and acid oligotrophic lakes. The average biomass in eutrophic lakes was 5.57 g m−3, in dyseutrophic 3.54 g m−3, 1.23 g m−3 in mesotrophic, 0.52 g m−3 in oligotrophic and 0.39 g −3 in acid oligotrophic lakes. The average number of taxa per sample in the corresponding lake types were 109. 1, 79.3, 97.9, 90.9 and 43.8, respectively. The phytoplankt…
Biochemical, morphological and immunological findings in a patient with a cutis laxa-associated inborn disorder (De Barsy syndrome).
1986
Clinical symptoms of a male infant are described and compared with cases now classified as the De Barsy syndrome, a distinct disorder related to cutis laxa. Morphologically, clastic fibres in skin were frayed and reduced in number and density. The collagen fibril network was normal. Biochemical studies on collagen metabolism in a skin specimen and in cultured skin fibroblasts showed a normal amino acid content and a normal electrophoretic pattern of collagen constituents. The chemotactic migration of cultured fibroblasts was diminished when compared with fibroblasts from donors of different age groups. Immunological investigations revealed an impaired granulocyte function.
On the growth of maars and diatremes and its relevance to the formation of tuff rings
1986
Small and large maars exist associated with small and large diatremes, respectively, their subsurface feeder structures. The problem of size and growth of maar-diatreme volcanoes is discussed from a phreatomagmatic point of view from field data, some geophysical data, and short-lived historic maar eruptions. A hydrostatic pressure barrier of usually about 20–30 bars is assumed to control the maximum depth level of explosive magma/groundwater interactions. Similar to the situation in submarine and subglacial volcanism, initial maar-forming water vapour explosions are therefore assumed to occur at shallow depth and to produce a small maar with a shallow diatreme. Because of limited availabili…
The Structure and the Stereochemistry of Atractyliretin
1986
The nor-kaurane diterpene Atractyliretin was obtained by acid hydrolysis of Atractyloside, a toxic substance isolated from ATRACTYLIS GUMMIFERA L (Compositae). On the basis of spectral (IR, (1)H-NMR, (13)C-NMR and MS) analysis and chemical degradation its structure and stereochemistry was identified as 4.
Textures and c-axis orientations of deformed quartz crystals from porphyric dikes of the Alpine »Root Zone« (Western Alps)
1986
Deformation textures and c-axis preferred orientations of quartz phenocrysts from porphyric dikes of the Alpine »Root Zone« have been formed under conditions of greenschist to low amphibolite facies. It is shown that the deformation textures as shear planes and kink bands, boudins, grain boundary sutures, subgrains, coarse and fine recrystallized grains, deformation lamellae and fractures are developed in a chronological sequence during first increasing and later decreasing temperatures. The c-axis orientations are chiefly influenced by kinking during the early stage of metamorphism and later by recrystallization but not by the initial orientations of the c-axes. The shape of crossed-girdle…
European vestibular experiments on the Spacelab-1 mission: 7. Ocular counterrolling measurements pre- and post-flight.
1986
The static ocular counterrolling (OCR) of the four scientific crew members in the first Spacelab mission was measured during baseline-data-collection before and after the flight of SL-1. It was presumed that the modification of otolithic responses during spaceflight will be reflected in specific changes of the OCR-gain on the first days after recovery. The magnitude of OCR was determined analysing colour-transparencies of subjects right eyes that were produced in different positions of lateral body tilt. In general, one subject did not show any changes at all; three subjects exhibited a significant decrease of OCR-gain after exposure to weightlessness, whereby differences could be found bet…
European vestibular experiments on the Spacelab-1 mission: 2. Experimental equipment and methods
1986
A series of vestibular experiments were performed in conjunction with the first Spacelab mission, consisting of sets of pre-, in- and postflight tests. A multipurpose experimental apparatus used for the diverse flight and ground tests is presented. Additional apparatus together with the multi-purpose package were used in the baseline data collection facility at the landing site at NASA Dryden Flight Research Facility for the ground tests. The tests involved optokinetic, caloric and mechanical (whole-body or head-alone) stimulation. The latter included linear acceleration in the subject's x, y and z axes, static roll and yaw about an earth-vertical axis. Physiological parameters such as elec…
Acquisition of thermotolerance in sea urchin embryos correlates with the synthesis and age of the heat shock proteins.
1986
Preheating at 31 degrees C induces thermotolerance in Paracentrotus lividus embryos, which therefore become able to withstand 1-h treatment at the otherwise lethal temperature of 35 degrees C, and to develop normally. The acquisition of thermotolerance is positively correlated with the amount of heat shock proteins produced during the 31 degrees C treatment. Evidence is provided that the heat shock proteins, although present in the embryo for long periods after synthesis, lose their effect on thermotolerance within 3 h of the cessation of synthesis.
Notation et orientation : quelle cohérence, quelle conséquence ?
1986
International audience; Ce texte s'articule autour de deux idées simples, qui vont être complexifiées par une analyse extrêmement précise : les évaluations scolaires ont un rôle important dans l'orientation, d'une part. D'autre part, les évaluations scolaires supportent un certain nombre de biais. Cette analyse apporte du même coup des éléments précis sur les mécanismes des inégalités sociales face à l'orientation ; elle permet de chiffrer ce qui, dans les inégalités sociales importantes que l'on constate au niveau de ce premier pallier d'orientation que constitue la fin de 5ème, dans le système scolaire français revient aux inégalités sociales de réussite sédimentées pendant toute la scola…
Potentialités de croissance et de fertilité du bourgeon latent chez la vigne (<em>Vitis vinifera</em> L.), étude réalisée de l'initiation…
1986
<p style="text-align: justify;">Les potentialites de croissance et de fertilité du bourgeon latent de rang 6 (<em>Vitis vinifera</em> L, cépage Pinot noir) sont étudiées grâce à des techniques de forçage pratiquées au vignoble. Ces techniques sont appliquées au bourgeon latent depuis l'état méristématique jusqu'à son entrée en dormance.</p><p style="text-align: justify;">Les potentialités de croissance importantes diminuent en même temps que la dormance s'installe.</p><p style="text-align: justify;">Nous avons montré qu'il est possible d'obtenir une certaine fertilité à partir de bourgeons qui n'ont pas encore formé d'inflorescences au moment des fo…
Coste y financiacion de la universidad espanola
1986
International audience; Education, as any other activity, is hard to produce. Not only is it difficult to produce for the community in charge of teaching services, but also for the fellows who receive the instruction, as they bear, besides the direct expenses of their education, the opportunity costs, mainly in form of an unwon salary. We will primordially refer to the first of the two mentioned aspects of the cost of higher education, without denying the importance of the private expenses in higher education-rather difficult to cipher as a result of the shortage of adequate statistics, on the other hand. In that way, the purpose of this work is, firstly, to describe the recent evolution of…
Les nouvelles technologies dans l'enseignement de base : analyse coût-efficacité
1986
International audience