Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    EGRET Observations of Gamma-Ray Bursts (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 759 (1995), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Notes: The Energetic Gamma-Ray Experiment Telescope (EGRET) has observed gamma-rays bursts with the highest energy gamma-rays and the longest high energy emission to date. EGRET measures the high energy gamma-rays with its large NaI scintillator (1 to 200 MeV) and its spark chamber (30 MeV to 30 GeV). The spark chamber also measures time and arrival directions of individual photons allowing locations for the energetic bursts to be determined. Since the Compton Gamma Ray Observatory launch in 1991, EGRET has observed five bursts in the spark chamber with several having gamma-ray energies grater than 1 GeV. The recording breaking burst, GRB940217, had gamma-rays up to 18 GeV and lasted over 5000 seconds. The results for the energetic bursts are presented. The high energies observed from these gamma-ray bursts set constraints for the burst distances.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1995.tb17577.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    THE EFFECTS OF SYMPATHOLYTIC DRUGS ON THE CARDIOVASCULAR RESPONSE TO TILTING IN ANAESTHETIZED CATS (1978)
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 5 (1978), S. 0 
    Details
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. Using cats anaesthetized with chloralose and urethane, comparison was made of the abilities of several antihypertensive and sympatholytic drugs to lower systemic blood pressure, and to depress the compensatory cardiovascular responses to bilateral carotid occlusion and to 45° head-up tilting. Similar comparisons were also made of the effects of these drugs on the perfusion pressure of the vascularly isolated autoperfused hindquarters, and the response of this to carotid occlusion and tilting. The effects of bilateral vagotomy and haemorrhage on these responses were also studied.2. It was found that hypotensive doses of both bretylium and guanethidine (3.0mg/kg, i.v.) markedly depressed the ability of cats to restore their systemic blood pressure and to constrict their hindquarters vasculature during tilting. Both drugs depressed the carotid occlusion reflex in the systemic, but not in the hindquarters, circulation. Neither propranolol, 2.0mg/kg, i.v., nor bilaterial vagotomy had any effect on these parameters and haemorrhage sufficient to cause marked hypotension was without effect on the systemic responses to carotid occlusion or tilting.3.Clonidine (1.0, 5.0 and 25/μg/kg, i.v.), xylazine (62.5, 125 and 250μg/kg, i.v.) and reserpine (0.5 and 2.0mg/kg, i.v.) all caused considerable hypotension but had no effect on the response to tilting of the systemic circulation, apart from somewhat prolonging recovering time. The highest dose of clonidine moderately depressed the hindquarters perfusion pressure, and the response of this to tilting.4. Clonidine (5.0 and 25μg/kg, i.v.) and xylazine (125 and 250/μg/kg, i.v.) depressed the systemic pressor responses elicited by the ganglion stimulants DMPP and McN-A-343. This may indicate that the ability of clonidine to prolong the pressure recovery during tilt may be due to impaired peripheral sympathetic transmission.5. It is concluded that drugs which significantly reduce the compensatory pressure responses to tilting in anaesthetized cats may also cause postural disturbances in man, whilst drugs which merely prolong the period required for pressure compensation seem much less likely to cause serious clinical impairment of orthostatic reflexes. It appears that the cardiovascular response to bilateral carotid occlusion may not provide a good index of the integrity of orthostatic reflexes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1440-1681.1978.tb00693.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    THE EFFECTS OF SEROTONIN PRECURSORS ON THE PRESSOR RESPONSE TO INTRAVENOUS CLONIDINE IN CONSCIOUS RATS (1977)
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 4 (1977), S. 0 
    Details
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. The interaction of the biosynthetic precursors of serotonin with the a-adrenoceptor-mediated pressor response to intravenous clonidine was investigated in unanaesthetized rats.2. Pretreatment with 100 mg/kg of either L-tryptophan or 5-hydroxytryptophan (5-HTP) reduced the magnitude of the pressor response elicited by intravenous clonidine (25 μg/kg) to 15% and 11%, respectively, of that observed in control rats.3. The depression by L-tryptophan of the clonidine-induced pressor response could be prevented by pretreatment with either the L-aromatic amino acid de-carboxylase inhibitor Rö-4– 4602 or the serotonin antagonist methysergide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1440-1681.1977.tb02688.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    THE EFFECTS OF INTRACISTERNAL ADMINISTRATION OF α-ADRENORECEPTOR AGONISTS ON THE SYSTEMIC BLOOD PRESSURE AND ITS RESPONSE TO HEAD-UP TILTING IN ANAESTHETIZED CATS (1978)
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 5 (1978), S. 0 
    Details
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. The effects of intracisternal injections of the α-adrenoreceptor agonists clonidine (0.2, 0.63 and 2.0μg/kg), xylazine (0.5, 8.0 and 50μg/kg), oxymetazoline (2.0 and 8.0μg/kg), noradrenaline (12.5, 50 and 100μg/kg) and α-methylnoradrenaline (5.0 and 25;μ/kg) on mean arterial pressure and the reflex pressure responses to bilateral carotid occlusion and 45° vertical head-up tilting have been investigated in chloralose-urethane-anaesthetized cats.2. All the a-adrenoreceptor agonists tested caused dose-dependent reductions in mean arterial pressure (P〈0.05, Anova, d.f. = 1,58) and the reflex pressor response to bilateral carotid occlusion (P 〈 0.05, Anova, d.f. = 1,58).3. Only xylazine (50μg/kg) and noradrenaline (100μg/kg) produced a significant depression of the magnitude of the pressure compensatory response to tilting (P〈0.05, Anova, d.f. = 1, 58) whilst all the agonists tested caused an increase in the period required for pressure compensation to occur (P〈0.05, Anova, d.f. = 1,58).The action of the a-adrenoreceptor agonists to depress mean arterial pressure and the reflex responses to bilateral carotid occlusion and tilting could be reversed by the subsequent intracisternal injection of the a-adrenoreceptor antagonist piperoxane (50 or 100μg/kg).5.Clonidine (0.63 μg/kg) decreased the perfusion pressure of the vascularly isolated autoperfused hindquarters (P〈0.05, Anova, d.f. = 1,19), but had no significant effect on the reflex rises in perfusion pressure evoked by bilateral carotid occlusion or tilting. Noradrenaline (50 jug/kg) significantly reduced the reflex response to tilting (P〈0.05, Anova, d.f. = 1,19), but had no effect on the other hindquarter parameters. Oxymetazoline (8.0 μg/kg) caused no significant change in any of these parameters.6. It is concluded that intracisternally administered a-adrenoreceptor agonists may cause some depression of orthostatic cardiovascular reflexes via a central interaction with adrenergic mechanisms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1440-1681.1978.tb00694.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    L-TRYITOPHAN-INDUCED DEPRESSION OF THE PRESSOR RESPONSE TO CLONIDINE IN ANAESTHETIZED RATS (1978)
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 5 (1978), S. 0 
    Details
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. The interaction of the serotonin precursor L-tryptophan with the pressor responses of the anaesthetized rat to the intravenous injection of clonidine, adrenaline and angiotensin has been studied.2. Pretreatment of rats with L-tryptophan (100 mg/kg) depressed the pressor response to clonidine but had no effect on the responses elicited by adrenaline or angiotensin.3. The L-tryptophan-induced depression of the clonidine response was prevented by pretreating rats with either Rö 44602, carbidopa, BW 172C58, methys-ergide or by pithing.4. Intravenous infusions of serotonin depressed the pressor responses to clonidine, adrenaline and angiotensin in both intact anaesthetized and pithed rats.5. It is concluded that the depressant action of L-tryptophan is dependent on its conversion within the periphery to serotonin. This action is also dependent on or mediated by the sympathetic nervous system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1440-1681.1978.tb00672.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A LONG TERM STUDY OF HIGH ENERGY GAMMA RAY EMISSION FROM THE VELA, GEMINGA AND CRAB PULSARS (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 759 (1995), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1995.tb17543.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Spectral feature of 31 December 1981 γ -ray burst not confirmed (1984)
    [s.l.] : Nature Publishing Group
    Nature 311 (1984), S. 360-362 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Annihilation lines have been reported in 5% of the bursts observed by the Konus instruments from 1978 to 19821'3. The typical emission features observed by Konus are centred at 400-450 keV and have widths of -200 keV (FWHM). The strong feature in the 5 March 1979 burst2 fits this description; ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/311360a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Pulsed high-energy γ-rays from the radio pulsar PSRI706–44 (1992)
    [s.l.] : Nature Publishing Group
    Nature 359 (1992), S. 615-616 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Following the SAS-2 and COS-B high-energy y-ray observations of the Crab (0531 + 21) and Vela (0833-45) pulsars1'2, searches were made for additional y-ray pulsars3'5. No other positive results were then found, but calculations have indicated that y-ray emission is likely from other ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/359615a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Pulsed high-energy γ-radiation from Geminga (1E0630+178) (1992)
    [s.l.] : Nature Publishing Group
    Nature 357 (1992), S. 306-307 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The y-ray source Geminga (2CG195 + 04) was first seen by the SAS-2 satellite (refs 2-4) in observations made roughly 20 years ago. Then, as now, it was one of the three strongest high-energy y-ray sources in the sky, the other two being the Crab and Vela pulsars PSR0531 + 21 and ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/357306a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Hard X-ray spectrum of Cygnus X-l (1981)
    [s.l.] : Nature Publishing Group
    Nature 293 (1981), S. 275-277 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Our observations were made with two instruments on the HEAO 1 satellite, in the spacecraft's scanning mode, in which the X-ray detectors scanned great circles on the sky once every 30 min, covering the entire sky in six months. The lowest-energy data (3-40 keV) came from one of the xenon ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/293275a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...