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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 534-546 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We demonstrate and analyze a novel scheme for complete transfer of atomic or molecular population between two bound states, by means of Stark-chirped rapid adiabatic passage (SCRAP). In this two-laser technique a delayed-pulse laser-induced Stark shift sweeps the transition frequency between two coupled states twice through resonance with the frequency of the population-transferring coupling laser. The delay of the Stark-shifting pulse with respect to the pulse of the coupling-laser Rabi frequency guarantees adiabatic passage of population at one of the two resonances while the evolution is diabatic at the other. The SCRAP method can give a population-transfer efficiency approaching unity. We discuss the general requirements on the intensity and timing of the pulses that produce the Rabi frequency and, independently, the Stark shift. We particularly stress extension to a double-SCRAP technique, a coherent variant of stimulated emission pumping in the limit of strong saturation. We demonstrate the success of the SCRAP method with experiments in metastable helium, where a two-photon transition provides the Rabi frequency. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science, Ltd
    Clinical & experimental allergy 32 (2002), S. 0 
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background The results of numerous studies on the influence of breastfeeding in the prevention of atopic disorders are often contradictory. One of the most important problems is confounding by other lifestyle factors.Objective The aim of the present study was to analyse the effect of any breastfeeding duration on the prevalence of atopic eczema in the first seven years of life taking into account other risk factors.Methods In an observational birth cohort study 1314 infants born in 1990 were followed-up for seven years. At 3, 6, 12, 18, 24 months and every year thereafter, parents were interviewed and filled in questionnaires, children were examined and blood was taken for in vitro allergy tests. Generalized Estimation Equations (GEE)-models were used to model risk factors for the prevalence of atopic eczema and for confounder adjustmentResults Breastfeeding was carried out for longer if at least one parent had eczema, the mother was older, did not smoke in pregnancy, and the family had a high social status. The prevalence of atopic eczema in the first seven years increased with each year of age (OR 1.05; 95% CI 1.01–1.09 for each year), with each additional month of breastfeeding (1.03; 1.00–1.06 for each additional month), with a history of parental atopic eczema (2.06; 1.38–3.08), and if other atopic signs and symptoms appeared, especially specific sensitization (1.53; 1.25–1.88), and asthma (1.41; 1.07–1.85). Although breastfeeding should be recommended for all infants, it does not prevent eczema in children with a genetic risk.Conclusion Parental eczema is the major risk factor for eczema. But in this study, each month of breastfeeding also increased the risk
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford BSL : Blackwell Science Ltd
    Clinical & experimental allergy 30 (2000), S. 0 
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Allergic diseases are more prevalent in affluent countries, which has been attributed to life-style factors. Life-style habits may also differ between socioeconomic (SES) classes. The objective of this paper therefore was to evaluate if SES had an impact on the development of atopic disorders.〈section xml:id="abs1-2"〉〈title type="main"〉MethodsA total of 1314 German children were followed-up in an observational birth cohort study to 6 years of age. Parents filled in questionnaires, and had multi-allergen screening tests for sensitization. Indoor allergen concentrations were determined by ELISA. Children were examined regularly up to 6 years, specific serum IgE values were determined by CAP-Rast-Feia.〈section xml:id="abs1-3"〉〈title type="main"〉ResultsThe risk of aeroallergen sensitization (odds ratio 1.76; 95% CI 1.30–2.37), and the lifetime prevalence of hay fever (2.36; 1.76–3.17), and asthma (1.74; 1.08–2.80), but not of atopic dermatitis (AD: 0.90; 0.54–1.51) was elevated in parents of high compared to low SES. With high SES the risk of smoking in pregnancy (0.35; 0.23–0.51), in the home (0.31; 0.21–0.46), pet ownership (0.37; 0.26–0.55), high mite (0.42; 0.25–0.74), and high cat (0.38; 0.18–0.82) allergen concentration in house dust was reduced, but elevated for breastfeeding over more than 6 months (4.67; 2.9–7.48). In children, even after controlling for other risk factors, only the risk of AD from 3 to 6 years (2.42; 1.42–4.14) was elevated in families with high SES, but not of AD in infancy or of any other atopic disorder.〈section xml:id="abs1-4"〉〈title type="main"〉ConclusionsWhile parents of high SES have a higher prevalence of inhalative allergies, their favourable life-style prevents the development of atopic disorders in their children, except for AD beyond infancy.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Objective:  A population study was performed to identify the prevalence of all kinds of adverse reactions to food.Methods:  In a representative cross-sectional survey performed in 1999 and 2000 in Berlin, 13 300 inhabitants of all ages were addressed by questionnaire. This questionnaire was answered by 4093 persons. All respondents mentioning any sign of food intolerance or the existence of allergic diseases (n = 2298) were followed up by telephone and, in case food intolerance could not be ruled out by patient history, were invited to attend to the clinic for personal investigation including double-blind, placebo-controlled food challenge tests (DBPCFC).Results:  The self-reported lifetime prevalence of any adverse reaction to food in the Berlin population (mean age 41 years) was 34.9%. Eight hundred and fourteen individuals were personally investigated according to the guidelines. The point prevalence of adverse reactions to food confirmed by DBPCFC tests in the Berlin population as a mean of all age groups was 3.6% (95% confidence interval [3.0–4.2%]) and 3.7% in the adult population (18–79 years, 95% confidence interval [3.1–4.4.%]). Two and a half percent were IgE-mediated and 1.1% non-IgE-mediated, females were more frequently affected (60.6%). Based on a statistical comparison with available data of adults from the nationwide German Health Survey from 1998, adverse reactions to food in the adult population of Germany (age 18–79) were calculated with 2.6% [2.1–3.2%]).Conclusions:  The study gives for the first time information about the point prevalence of both immunological and nonimmunological adverse reactions to food and underlines the relevance of this issue in public health. The data also show that an individualized stepwise approach including provocation tests is mandatory to confirm the diagnosis.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Copenhagen : Munksgaard International Publishers
    Allergy 55 (2000), S. 0 
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    European archives of oto-rhino-laryngology and head & neck 220 (1978), S. 299-301 
    ISSN: 1434-4726
    Keywords: Fluorocarbon ; O2-Solubility ; Perfusion ; Cochlea ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Because oxygen is at least ten times as soluble in fluorocarbon liquids as in plasma or saline, we investigated the principle possibility of perilymphatic perfusion of the cochlea with perfluortributylamin. Our experiments show that fluorocarbons in spite of the excellent O2-solubility in it are not suitable for the perilymphatic perfusion due to their physical properties (density 1.91 g/ml, non-solubility in water, necessity and difficulties of emulsification).
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    European archives of oto-rhino-laryngology and head & neck 224 (1979), S. 257-265 
    ISSN: 1434-4726
    Keywords: Guinea pig ; Cochlear aqueduct ; Round window membrane ; Cerebrospinal fluid ; Perilymph ; Protein concentration ; Electrophysiology ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To prevent the perilymph (guinea pig) from contamination with CSF during the sampling the aqueductus cochleae (AC) was blocked by injection of tissue adhesive into the meningeal aperture. The control of an exact blockage of AC was carried out by examination of perilymph-outflow after opening the cochlea (injection of fluorescein-Na into the CSF-space), analysis of perilymphprotein-concentration, macroscopic and microscopic examination of the temporal bones. In all cochleae we have found the same morphological structures, notwith-standing whether the AC was blocked (for a time from 30 min to 7 weeks) or not: The cochlear aqueduct is filled with a mesh of mesenchymal tissue, which grows more dense towards the cochlear aperture and continues into the round window membrane. From scala tympani the AC is always limited by one layer of cells forming a sort of membrane (under light microscope). It seems possible that CSF moves in the inner of the round window membrane between AC and subepithelian space of middle ear mucosa, whereas perilymph of scala tympani is not in direct contact with the flow of CSF. The scala tympanic side of the round window membrane may be a big area for diffusion and there also may be an exchange between CSF and perilymph. The outflow of CSF into the cochlea after experimental opening of the cochlea is an artifact, caused by damage of pressure equilibration between CSF-space and cochlea. 30 min and 5–7 weeks after blockage no morphological and electrophysiological alterations from those of the control ears were to be seen. The protein concentration, however, increased significantly 5–7 weeks after blockage from normally about 200 mg/100 ml to almost the double especially in the scala tympani (see Table 1).
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Applied physics 8 (1975), S. 65-70 
    ISSN: 1432-0630
    Keywords: Nozzle beams ; Laser Diagnostic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The output from a stabilized, tunable single-mode laser is split into two beams which cross the molecular beam perpendicularly and at an angle of β to the beam axis. Tuning the laser frequency across the unshifted and Doppler-shifted absorption profile of the molecular transition yileds the velocity distribution of the molecules in the beam for individual quantum states. The internal state distribution among vibrational and rotational levels in the beam can be determined by comparing the fluorescence simultaneously induced in the beam and in a cell with molecules in thermal equilibrium.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    International archives of occupational and environmental health 42 (1978), S. 119-127 
    ISSN: 1432-1246
    Keywords: Organic dusts ; Allergic alveolitis ; Bird fancier's lung ; Immunology ; Counter-immunoelectrophoresis ; Sensitisation ; Pulmonary function diagnosis ; Ventilation ; Respiratory mechanics ; Diffusion ; Distribution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Studies to detect disorders of pulmonary function were performed on 42 workers at a poultry farm. All the subjects were exposed to organic dusts and sensitised to poultry antigens. Typical signs of bird fancier's lung were recorded in two of them. Included in all examinations were immunological diagnosis by means of counter-immunoelectrophoresis, systematic interviewing for case histories, and registration of respiratory symptoms. Pulmonary function was recorded by means of the following techniques: analysis of ventilation (flow-volume indices), respiratory mechanics of the larger airways and lung (body box plethysmography, oesophago-balloon technique), respiratory mechanics of the small airways (closing volume), distributional analysis, diffusion analysis, and blood gas analysis. A disorder of pulmonary function was recordable in 40 sensitised individuals. Such disorder being characterised by obstruction of the larger airways and slight inhomogeneity. The small airways were not narrowed. No restriction nor disturbed diffusion were established. The severity of obstruction was found to be related to the degree of sensitisation. The following more clearly pronounced changes in terms of functional diagnosis were recordable from two poultry workers with allergic alveolitis: obstruction of larger airways with concomitant restriction, marked inhomogeneity, and disorder of diffusion. The disorders, relatively discrete, led to mild PO2-reduction in sensitised individuals, whereas mild hypoxaemia was recorded from subjects with allergic alveolitis.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 287 (1975), S. 33-45 
    ISSN: 1432-1912
    Keywords: Bile Formation ; Lipid Secretion ; Phenobarbital ; Spironolactone ; Pregnenolone-16α-Carbonitrile
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of pretreatment for 4 days with the hepatic microsomal enzyme inducers phenobarbital (8 mg/100 g body weight), spironolactone (20 mg/100 g body weight) and pregnenolone-16α-carbonitrile (7 mg/100 g body weight) on bile flow and bile lipid secretion have been compared in rats. Similar to phenobarbital, spironolactone and pregnenolone-16α-carbonitrile increased bile flow but did not alter bile salt excretion, indicating that these agents increased bile salt independent bile formation. This finding could be substantiated for spironolactone by studies of the relationship between bile salt excretion and bile flow during bile salt infusions. Whereas phenobarbital decreased cholesterol and phospholipid secretion to 39 and 49%, respectively, spironolactone and pregnenolone-16α-carbonitrile more than doubled cholestal excretion without influencing phospholipid output. As a consequence, marked differences in the effect on cholesterol saturation were observed: a decrease by phenobarbital and an increase following spironolactone and pregnenolone-16α-carbonitrile. The present studies demonstrate that different types of enzyme inducers may share certain effects on bile formation and differ in others.
    Type of Medium: Electronic Resource
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