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  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Psychopharmacology 91 (1987), S. 397-402 
    ISSN: 1432-2072
    Schlagwort(e): Human ; Benzodiazepines ; Triazolam ; Dose level ; Sleep structure ; Arousal threshold ; Smoke detector alarm ; Heart rate
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Thirty-six young adult, male subjects with sleep-onset insomnia were equally divided into placebo, 0.25 mg, and 0.5 mg triazolam groups to examine the effects of the hypnotic, with particular attention to dose level on efficacy, sleep stages, and awakening to a smoke detector alarm. On nights 1 and 4 of a five-consecutive-night protocol, a standard home smoke detector alarm was sounded during stage 2, 5 min after sleep onset, in slow wave sleep (SWS), and at the time of the early morning awakening. The alarm registered 78 dB SPL at the pillow. EEG arousal latency and reaction time to a button press were studied. Failure to awaken to three 1-min alarm presentations was scored as “no response.” Both dose levels produced similar reductions in sleep latency, decreases in SWS, increases in stage 2, and increases in sleep efficiency. Both dose levels showed similar sedative effects to the smoke alarm. Fifty percent of triazolam subjects failed to awaken on night 1 during SWS, and EEG arousal and response latencies were significantly slowed. Some drug tolerance or sensitization to the alarm was seen by night 4. By morning, all subjects were easily awakened on both nights. The 0.25 mg dose is clearly an effective dose level for both sleep efficacy and sedative effects to outside noise, which in some instances could pose potantial problems.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Psychopharmacology 101 (1990), S. 160-167 
    ISSN: 1432-2072
    Schlagwort(e): Humans ; Benzodiazepines ; Caffeine ; Sleepiness ; Performance ; Mood
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract In a double-blind parallel group design, 80 young adult males were divided into eight treatment groups. Subjects received 15 or 30 mg flurazepam, 0.25 or 0.50 mg triazolam, or placebo at bedtime, and 250 mg caffeine or placebo in the morning for 2 treatment days. Two objective (Multiple Sleep Latency Test and lapses) and two subjective (Stanford Sleepiness Scale and Visual Analog Scale) measures of sleepiness, five performance tests, and two mood measures (Profile of Mood Scale and Visual Analog Mood Scale) were administered repeatedly on both days. Significant treatment effects were found for sleepiness but not for performance or mood. Early morning caffeine significantly antagonized next day hypnotic-induced drowsiness and enhanced alertness in the subjects who received bed-time placebo. Flurazepam, 30 mg, subjects were more sleepy than all other groups. Although not significantly different, the flurazepam, 30 mg, group demonstrated a trend toward poorer performance and a more negative mood than all other groups. Caffeine most improved performance of this group. In all groups, sleepiness was greatest and performance and mood poorest in early morning trials and caffeine was most effective at this time.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Journal of optimization theory and applications 62 (1989), S. 1-16 
    ISSN: 1573-2878
    Schlagwort(e): Inertia-preserving updates ; secant updates ; Broyden updates ; optimally conditioned updates ; SR1 update
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Mathematik
    Notizen: Abstract A class of rank-two, inertia-preserving updates for symmetric matricesH c is studied. To ensure that inertia is preserved, the updates are chosen to be of the formH +=FH c F t, whereF=I+qr t, withq andr selected so that the secant equation is satisfied. A characterization is given for all such updates. Using a parameterization of this family of updates, the connection between them and the Broyden class of updates is established. Also, parameter selection criteria that can be used to choose the optimally conditioned update or the update closest to the SR1 update are discussed.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Journal of optimization theory and applications 68 (1991), S. 203-203 
    ISSN: 1573-2878
    Schlagwort(e): Inertia-preserving updates ; secant updates ; Broyden updates ; optimally conditioned updates ; SRI update
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Mathematik
    Notizen: Abstract Corrections to the last two equations of Ref. 1 are given.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 12 (1985), S. 41-46 
    ISSN: 0148-7280
    Schlagwort(e): spermatozoa ; stallion ; crater defect ; electron microscopy ; nuclear ultrastructure ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: The appearance of the nuclear abnormality “crater defect” is described in spermatozoa from the domestic horse (Equadae). Under scanning electron microscopy, the defect appears as a severe depression at any area of the sperm nucleus or as a blister or swelling at some point on the sperm nucleus. Ultrastructurally, the crater appears as a nuclear vacuole containing amorphous material similar to that described in bull and boar sperm. The craters ranged in size from 0.5 to 2 μm in diameter. Within ejaculates of stallions having this defect, the percentages of sperm with crater defects varied widely over time, being as high as 60% and as low as 15%.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    ISSN: 0148-7280
    Schlagwort(e): spermatozoa ; boar ; crater defect ; electron microscopy ; nucleus ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: Nuclear vacuoles resembling the “crater defect” described in bull spermatozoa were observed in 14 boars. Both the incidence of the defect and semen quality were monitored with phase contrast microscopy over a three-month period. The percentages of cratered spermatozoa varied widely both among boars and in ejaculates from the same boar taken on different days. The presence of cratered spermatozoa at a level of 5% or more appeared to be associated with low semen quality. The defect was studied with scanning and transmission electron microscopy and was found to consist of nuclear invaginations, about 0.5 μm in diameter, containing some scanty amorphous electron-dense material. In boars showing a high incidence of spermatozoa with crater defects, abnormalities of the acrosome and perforatorium were common.
    Zusätzliches Material: 11 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Gamete Research 20 (1988), S. 83-92 
    ISSN: 0148-7280
    Schlagwort(e): spermatozoal ; separation ; flow cytometry ; semen sexing ; electron microscopy ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: Bovine spermatozoa were fractionated on Percoll density gradients into two major subpopulations of motile spermatozoa and a minor fraction containing mostly nonmotile spermatozoa with abnormal morphology. Fractionation required the addition of bovine serum albumin and a continuous Percoll gradient buffered with sodium bicarbonate. It is postulated that, under suitable ionic conditions, the binding of bovine serum albumin to spermatozoa amplifies subtle differences between subpopulations. These studies were directed toward separating Y- and X-bearing spermatozoa. However, when the subpopulations were evaluated by flow cytometry, their Y:X ratios were similar to that of an unfractionated control.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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