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  • Electronic Resource  (4)
  • amplitude modulation  (2)
  • Alcotest 7110 Evidential MK III  (1)
  • Angiotensin II  (1)
  • 1
    ISSN: 1432-1440
    Keywords: Plasma renin activity ; Angiotensin II ; Cardiac edema ; Furosemide ; Regulation of sodium balance ; Plasma-Renin-Aktivität ; Angiotensin II ; kardiale Hydropsie ; Furosemid ; Regulation des Naturiumhaushaltes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An 8 Gesunden und 21 Kranken mit kardialer Insuffizienz wurden Renin-Aktivität (PRA) und Angiotensin II-Konzentration (A II) im Plasma, Serumnatrium und -kalium und renale Na+-, K+- und Flüssigkeitsexkretion vor sowie 2, 4 und 6 Std nach i.v. Gabe von 0,3 mg Furosemid/kg untersucht. Die PRA wurde biologisch, A II radioimmunologisch bestimmt. Die Gesunden reagierten mit signifikanten Anstiegen der PRA- und A II-Werte (P〈0,005), die Kranken mit kardialer Insuffizienz zeigten 3 verschiedene Verhaltensmuster der PRA: Absinken unter den Ruhewert (4 Fälle), Anstieg (4 Fälle) und Gleichbleiben (14 Fälle, davon 11 ohne meßbare PRA). Eine mangelhafte Stimulierbarkeit der PRA ist somit auch bei kardialer Hydropsie möglich. Die Pat. mit abfallender bzw. gleichbleibender PRA waren vornehmlich Schwerkranke mit ausgeprägter Hydropsie; sie wiesen nach Furosemid im Mittel gleich große, im einzelnen z.T. weit höhere Na+-Verluste auf als die Gesunden. Dies könnte durch die Annahme eines (zentralnervösen) Systems erklärt werden, das die renale Na+-Verlustrate in Beziehung zum Na+-Gesamtbestand setzt und erst ab einer kritischen Relation gegenregulatorisch die Steigerung der Reninfreisetzung veranlaßt. Diese Vermutung wurde durch Untersuchung einer Patientin vor und nach Ödemausschwemmung wahrscheinlich gemacht. PRA- und A II-Werte verhielten sich konkordant (r=+0,627,P〈0,001).
    Notes: Summary In 21 patients with congestive heart failure and 8 normal controls plasma renin activity (PRA), angiotensin II (A II), sodium and potassium concentrations in plasma and renal Na+, K+, and water excretion were measured before and 2, 4, and 6 hours after an intravenous injection of Furosemide (0.3 mg/kg). PRA was determined biologically, A II by radioimmunoassay. The control group showed a significant increase of PRA and A II levels (P〈0.005). In patients with congestive heart failure, three different patterns of PRA were observed: decrease (4 cases), increase (4 cases) and no change (14 cases which comprise 11 patients without detectable PRA), compared to the individual control value. Thus, inadequate stimulation of PRA may occur in congestive heart failure, too. Particularly the patients with decreasing or unchanged PRA suffered from severe cardiac insufficiency with severe edema. After application of Furosemide, these patients showed in average the same, some of them a much higher Na+ loss than the controls. These results could be explained by the assumption of the presence of a control mechanism, possibly located in the brain, that detects the renal Na+ excretion in relation to the total body Na+ and induces the counterregulatory renin secretion not unless a certain reference value is attained. This hypothesis was supported by the results obtained in the same patient before and after loss of edema. PRA and A II values were concordant (r=+0.627,P〈0.001).
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-5196
    Keywords: Schlüsselwörter Blutalkohol ; Atemalkohol ; Alcotest 7110 Evidential MK III ; BAK/AAK-Quotient ; AAK-Grenzwert im Strafrecht ; Keywords Blood alcohol ; Breath alcohol ; Alcotest 7110 evidential MK III ; Blood/breath alcohol ; quotient
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Description / Table of Contents: The Alcotest 7110 Evidential MK III breath analyser calibrated and approved by PTB in Brunswick is a reliable instrument for measuring breath alcohol concentrations. The results obtained from experimental investigations of the variability of the blood alcohol-to-the breath alcohol ratio expressed by the quotient QBlAC/BrAC were basically identical to the theoretical calculations presented by Wehner et al. Based on the results obtained from experimental investigations to establish a factor for converting breath alcohol into blood alcohol concentrations, an opinion of the Bundesgesundheitsamt of 1992 indicated a blood alcohol to breath alcohol ratio of 2.098 ±0.11 rounded to 2.1 as proposed by Schoknecht [17]. The mean value established in the present paper from 455 sample pairs taken at the same time was 2.2. The maximum value was 3.29 and the minimum value was 0.74. The standard deviations were basically identical to the theoretical calculations of Wehner et al. [19]. Theoretically, the quotients established could be used as factors for converting breath alcohol into blood alcohol concentrations. However, due to large variability breath alcohol concentrations should not be converted into blood alcohol concentrations and vice versa in forensic opinions. This seems to be also true for the use of „transformed“ blood alcohol concentrations for back calculation to the time of offence and alleged after-drink. In particular, as a breath alcohol limit value relevant to criminal law cannot be calculated by a simple multiplication operation, solid research into the physiological and traffic-medical foundations as well as experiments are required to provide a reliable solution.
    Notes: Mit dem Alcotest 7110 Evidential MK III, durch die PTB in Braunschweig zugelassen und geeicht, steht ein hochwertiges Gerätesystem zur Messung der Alkoholkonzentration in der Ausatemluft zur Verfügung. Der Umrechnungsfaktor von Atem- in Blutalkoholkonzentrationen wurde von Schoknecht [17] im Gutachten des Bundesgesundheitsamtes 1992 experimentell als BAK/AAK-Quotient mit 2,098 ±0,11 bestimmt und auf 2,1 gerundet. Der Mittelwert von 455 zeitgleichen Wertepaaren der vorliegenden Arbeit lag bei 2,2. Der Maximalwert betrug 3,29, der Minimalwert 0,74. Die Streubreite stimmte im Wesentlichen mit den theoretischen Berechnungen von Wehner et al. [19] überein. Die gefundenen Quotienten wären theoretisch als Umrechnungsfaktoren von AAK in BAK denkbar. Aufgrund der sehr großen Variabilität sollte aber grundsätzlich in forensischen Gutachten eine Transformation von AAK in BAK und umgekehrt nicht erfolgen. Demzufolge erscheint auch eine Rückrechnung mit „transformierten” BAK-Werten oder die Berücksichtigung von angegebenem Nachtrunk nicht möglich. Insbesondere ist ein strafrechtsrelevanter AAK-Grenzwert auch nicht durch einfache Multiplikation zu errechnen, sondern bedarf einer breiten experimentellen psycho-physiologischen und verkehrsmedizinischen Grundlagenforschung.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 18 (1997), S. 422-430 
    ISSN: 0197-8462
    Keywords: cellular phones ; EMFs ; biological effects ; amplitude modulation ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: We have previously demonstrated that microwave fields, amplitude modulated (AM) by an extremely low-frequency (ELF) sine wave, can induce a nearly twofold enhancement in the activity of ornithine decarboxylase (ODC) in L929 cells at SAR levels of the order of 2.5 W/kg. Similar, although less pronounced, effects were also observed from exposure to a typical digital cellular phone test signal of the same power level, burst modulated at 50 Hz. We have also shown that ODC enhancement in L929 cells produced by exposure to ELF fields can be inhibited by superposition of ELF noise. In the present study, we explore the possibility that similar inhibition techniques can be used to suppress the microwave response. We concurrently exposed L929 cells to 60 Hz AM microwave fields or a 50 Hz burst-modulated DAMPS (Digital Advanced Mobile Phone System) digital cellular phone field at levels known to produce ODC enhancement, together with band-limited 30-100 Hz ELF noise with root mean square amplitude of up to 10 μT. All exposures were carried out for 8 h, which was previously found to yield the peak microwave response. In both cases, the ODC enhancement was found to decrease exponentially as a function of the noise root mean square amplitude. With 60 Hz AM microwaves, complete inhibition was obtained with noise levels at or above 2 μT. With the DAMPS digital cellular phone signal, complete inhibition occurred with noise levels at or above 5 μT. These results suggest a possible practical means to inhibit biological effects from exposure to both ELF and microwave fields. Bioelectromagnetics 18:422-430, 1997. © 1997 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 14 (1993), S. 395-403 
    ISSN: 0197-8462
    Keywords: coherence time ; microwave ; amplitude modulation ; ornithine decarboxylase ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Previously, we demonstrated the requirement for a minimum coherence time of an applied, small amplitude (10 μT) ELF magnetic field if the field were to produce an enhancement of ornithine decarboxylase activity in L929 fibroblasts. Further investigation has revealed a remarkably similar coherence time phenomenon for enhancement of ornithine decarboxylase activity by amplitude-modulated 915 MHz microwaves of large amplitude (SAR 2.5 W/kg). Microwave fields modulated at 55, 60, or 65 Hz approximately doubled ornithine decarboxylase activity after 8 h. Switching modulation frequencies from 55 to 65 Hz at coherence times of 1.0 s or less abolished enhancement, while times of 10 s or longer provided full enhancement. Our results show that the microwave coherence effects are remarkably similar to those observed with ELF fields. © 1993 Wiley-Liss. Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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