Search results for "Rabbit"
showing 10 items of 553 documents
Funktionelle Bedeutung der Freisetzung von Dihydroxyephedrin und Dihydroxypseudoephedrin als ?falschen? sympathischen �bertr�gerstoffen am Herzen
1967
The experiments were carried out in order to investigate the functional significance of substitution of noradrenaline by amines known to exert actions weaker than those of the natural transmitter. On the isolated rabbit heart the potency relative to noradrenaline of (±)-dihydroxyephedrine to increase the rate was 1/4 and the potency to augment the contractile amplitude was 1/6. The corresponding values for (±)-dihydroxypseudoephedrine were 1/67 and 1/140, respectively.
In vivo investigations on microcirculatory disturbances induced by crenated erythrocytes following norepinephrine application
1974
Using a special apparatus for high resolution cinephotomicrography, which allows simultaneous observation and recording of microcirculatory changes, alterations in blood flow patterns and in red cell shape during norepinephrine acting have been studied. Under physiological conditions, and during slowing of capillary blood flow due to gradual removing of 20–25% of the circulating blood volume, the normal red cells are extremely deformable while passing through mesenteric capillaries. After application of norepinephrine a general arteriolar constrictive response in the bowel wall occurs, causing a further slowing of the capillary blood flow in the mesentery. Under these circumstances the eryt…
First-principles simulations for attosecond photoelectron spectroscopy based on time-dependent density functional theory
2018
We develop a first-principles simulation method for attosecond time-resolved photoelectron spectroscopy. This method enables us to directly simulate the whole experimental processes, including excitation, emission and detection on equal footing. To examine the performance of the method, we use it to compute the reconstruction of attosecond beating by interference of two-photon transitions (RABBITT) experiments of gas-phase Argon. The computed RABBITT photoionization delay is in very good agreement with recent experimental results from [Klünder et al., Phys. Rev. Lett. 106, 143002 (2011)] and [Guénot et al., Phys. Rev. A 85, 053424 (2012)]. This indicates the significance of a fully-consiste…
Autoradiographic technique to assess distribution of blood flow within organs
1969
A method is described for assessing the distribution of blood flow within organs. Microspheres, 5–50 μ in diameter, labelled with a beta-emitting isotope were injected into the left ventricle of experimental animals. The distribution of the indicator within the tissues, which is assumed to represent the regional distribution of flow, was visualized and measured quantitatively by autoradiography. Local flow rates in areas of about 1,2 mm in diameter could be determined. Application of the technique for the study of regional myocardial and renal circulation is demonstrated.
Inspiratory inhibition and rebound activation elicited by intermittent electrical bulbar stimulation in various states of pulmonary afferent vagal ex…
1975
In anesthetized rabbits spirogram and diaphragmatic activity were examined during electrical stimulation of regions of the medulla oblongata. The volleys were triggered by the animal's own respiration. 1. One volley of 120 msec duration at 100 pulses p.s., applied during inspiratory, caused an immediate and transient inhibition of the diaphragmatic activity. After the end of the volley and inspiratory rebound appeared: the tidal volume was increased and the inspiration was prolonged by some 150 msec. The respiratory rate decreased. 2. Continuous low or high frequency electrical stimulation of pulmonary stretch afferents caused an inspiratory or an expiratory effect respectively. In both con…
Synthesis of recombinant atrial natriuretic peptide (rANP) using hybrid fusion protein-phage fr coat/ANP (CP/ANP).
1997
Abstract Baumanis, V., I. Jansone, A. Skangals, I. Mandrika and V. Berzins. Synthesis of recombinant atrial natriuretic peptide (rANP) using hybrid fusion protein-phage fr coat/ANP (CP/ANP). Peptides 18(8) 1229–1235, 1997.—Recombinant atrial natriuretic peptide (rANP) was expressed in and isolated from E. coli. rANP was purified using HPLC. Amino acid analysis, partial sequencing, and molecular mass were determined. Fused protein was used to rise polyclonal antibodies and to develop of immunoenzymatic assays of rANP and CP/ANP. Experiments were designed to study rANP effects on isolated rabbit aortic strips and to examine hypotensive, diuretic, and natriuretic activity, as well as renal cre…
Humoral responses during wound healing in Holothuria tubulosa (Gmelin, 1788)
2021
Abstract Wounds in living organisms trigger tissue-repair mechanisms. The sea cucumber (Holoturia tubulosa) is an excellent model species for achieving a better understanding of the humoral and cellular aspects involved in such healing processes. Consequently, this study assesses data on its morphometric, physiological and humoral responses 1, 2, 6, 24 and 48h after wound induction. In particular, morphometric data on the weight, width, length and coelomic-fluid volume of the species were estimated at different times during our experiments. In addition, the humoral aspects related to the enzymatic activity of esterase, alkaline phosphatase and peroxidase, as well as the cytotoxic activity o…
The bulbar respiratory centre in the rabbit. I. Changes of respiratory parameters caused by intermittent electrical bulbar stimulation during inspira…
1976
In anesthetized rabbits, spirogram and diaphragmatic activity were examined during electrical stimulation of the bulbar lateral reticular formation. The activity of bulbar respiratory neurons was recorded contra-or ipsilaterally to the stimulation site. One volley of repetitive stimuli per breath was delivered during either inspiration or expiration. 1. Each volley of about 120 ms duration at 100 pulses per second, delivered early ininspiration, caused an immediate and transient inhibition of the diaphragmatic activity. An inspiratory, rebound comprising lengthening of inspiration and increase in tidal volume occurred. a) “Inspiratory” and “expiratory-inspiratory” phase-spanning neurons exh…
Activation of the first component of complement, C1: comparison of the effect of sixteen different enzymes on serum C1.
1983
In this study, the effect of sixteen different enzymes on serum C1 and its subcomponents was investigated. The sixteen enzymes could be divided into three groups. First, enzymes which activate native C1: trypsin (optimal concentration 2.4 x 10(-4) mM); alpha-chymotrypsin (2.3 x 10(3) mM); thrombin (1.0 x 10(-5) mM); plasmin (1.9 x 10(-5) mM); elastase (5.8 x 10(-5) mM); pronase (3.0 x 10(-6) mM). All these enzymes are serine esterase and activate native serum C1 bound to EAC4 at the given concentration within 10 min at 30 degrees C. Furthermore, native C1 inhibited by a pentosanpolysulfoester, Sp54, is unable to undergo the internal activation but can be externally activated by the serine e…
Mode of primary binding to target membranes and pore formation induced by Vibrio cholerae cytolysin (hemolysin).
1997
Vibrio cholerae cytolysin (VCC) is produced by many non-choleratoxigenic strains of V. cholerae, and possibly represents a relevant pathogenicity determinant of these bacteria. The protein is secreted as a pro-toxin that is proteolytically cleaved to yield the active toxin with a molecular mass of approximately 63 kDa. We here describe a simple procedure for preparative isolation of mature VCC from bacterial culture supernatants, and present information on its mode of binding and pore formation in biological membranes. At low concentrations, toxin monomers interact with a high-affinity binding site on highly susceptible rabbit erythrocytes. This as yet unidentified binding site is absent on…