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  • 1
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 84 (1986), S. 2907-2916 
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: NI in argon and in argon/10% N2 matrices has been excited into b 1Σ+, v'=0–4 with a pulsed tunable dye laser. The regular line structure in the fluorescence excitation and emission spectra in pure argon matrices is attributed to a local phonon progression of 15 cm−1, both in the X 3Σ− and b 1Σ+ states. "Hot'' local phonon lines, which originate in the thermally populated levels n'=1 and 2 of the local phonon mode at elevated temperatures, have been identified. The matrix lifetime of the vibrationally relaxed b state, which does not relax via the a state in pure argon, extrapolates to a radiative lifetime of 15 μs in vacuo, in satisfactory agreement with a recent gas phase determination. The a state of NI, which emits at 1185 and 1173 nm, could be populated via the b state only in mixed matrices of argon and N2. The lifetime in these matrices is 20.5±2 ms, which extrapolates to a gas phase radiative lifetime of approximately 38 ms. The b state of NI is completely quenched in pure nitrogen matrices, but emission from the a state is still detected with a lifetime of 4.6±0.5 ms. On the basis of these results recently reported a-state lifetimes of NCl and NBr in the ms to sub-ms range appear unreasonably low.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 87 (1987), S. 6266-6275 
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: NBr in solid argon has been excited to the b 1Σ+ state with a pulsed tunable dye laser. In addition to the well-known fluorescence spectrum of the b state, infrared emission from the vibrationally relaxed a 1Δ state was detected at 1086 nm. Three major trapping sites were resolved in absorption and fluorescence excitation spectra of the b–X system. Additional sites could be identified in the excitation spectrum of the a state, which is populated via the b state by internal conversion. There is a weak site effect on the lifetime of the vibrationally relaxed b state, which varies between 40 and 30 μs. Vibrational relaxation rates in the b state show a stronger site dependence. Internal conversion from b 1Σ+ to a 1Δ accounts for 〈0.1% to at least 17% of the decay rate of NBr b 1Σ+, v=0. Orbitally forbidden transitions to the X10+ component of the ground state were identified 23.0 to 25.5 cm−1 on the high-energy side of the more intense a 1Δ→X21± transition of several sites. The lifetime of the a state varies between 152±12 ms in the least perturbed site and 121±15 ms in the site with the strongest a 1Δ→X10+ forbidden component. NBr trapped in double vacancies of pure fcc argon, of single stacking faults, and of multiple stacking faults (hcp pockets) in argon, can account for the sites.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Terra nova 15 (2003), S. 0 
    ISSN: 1365-3121
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Geologie und Paläontologie
    Notizen: In the Basle region of Switzerland we demonstrate that rockfall blocks can be dated accurately using the radiocarbon method. Soil beneath rockfall blocks containing organic macro-remains was sampled at four cliff sites in the Tabular Jura south-east of Basle. A lightweight drilling rig drills a 101-mm-diameter hole through rockfall blocks up to 6 m in height. A downhole sampler is used to recover soil samples from below the blocks. Eighteen radiocarbon dates on charcoal, wood, needles of conifers and organic macro-remains from 11 blocks gave dates between 970 and 440 bp. Calibrated ages range between ad 1210 and ad 1450. These results, along with field observations and historical research, suggest that a large number of blocks toppled as rockfalls within a short time interval in the epicentral area of the ad 1356 Basle earthquake.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 524 (1988), S. 0 
    ISSN: 1749-6632
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Allgemeine Naturwissenschaft
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Science Ltd
    Clinical & experimental allergy 34 (2004), S. 0 
    ISSN: 1365-2222
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Objective Epinephrine (Epi) is the treatment of choice for reversing cardiovascular collapse in anaphylactic shock (AS). In this condition, most treatment guidelines have been anecdotally derived and no randomized clinical trials have been conducted. In the present study, we examined the time course of haemodynamic recovery in a canine model of AS when Epi was administered at the initiation of allergen challenge before fully developed shock had occurred.Methods Randomized, controlled, crossover studies were performed approximately 3–5 weeks apart in ragweed-sensitized dogs while the animals were ventilated and anaesthetized. Epi was administered by bolus intravenous (i.v.), subcutaneous (s.c.), intramuscular (i.m.) routes and by continuous i.v. infusion (CI). The findings obtained in the Epi treatment (T) studies were compared with those found in a no treatment (NT) study. In the bolus studies, Epi was administered at 0.01 mg/kg, while in the CI study, the dose of Epi was titrated to maintain mean arterial pressure (MAP) at 70% of preshock levels. MAP, cardiac output (CO), stroke volume (SV), and pulmonary wedge pressure (Pwp) were determined over a 3 h period.Results In the CI study, haemodynamics (CO, MAP, and SV) were significantly higher than those measured in the NT study and the bolus studies over approximately the first hour of the study. In the CI study, the amount of Epi infused was significantly less than in the bolus studies.Conclusion When administered at the initiation of allergen challenge, bolus treatment of Epi by i.m., i.v., or s.c. routes caused limited haemodynamic improvement in AS. In contrast, constant infusion of Epi at a lower total dose produced significant haemodynamic improvement. Within the limits of this anaesthetized canine model, the results suggest that CI should be the preferred route in the treatment of AS when this treatment option is available.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Copenhagen : Munksgaard International Publishers
    Dental traumatology 16 (2000), S. 0 
    ISSN: 1600-0595
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Abstract – Following a severe traumatic incident to permanent immature teeth, the growth of calcified tissue in the pulp space may occasionally occur. This calcified tissue may be diffuse or in intimate contact with the dentine. It has been suggested that a wide open apex, severe damage to the root sheath, and the absence of infection are only some of the predisposing factors leading to this metaplasia of pulp tissue into bone-like tissue. Five cases are described.
    Materialart: Digitale Medien
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  • 7
    ISSN: 1432-234X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The ultrastructure of the midgut epithelium of Phalangium opilio was examined. In the anterior part of the midgut the epithelium consists of three different types of cells, called resorption, digestion, and excretion cells according to their presumed functions. Excretion cells may represent old digestion cells. The relation between resorption and digestion cells needs further investigation. The epithelium of the posterior part of the midgut consists of two types, transport and secretion cells, which seem to serve mainly for the resorption of water and the secretion of peritrophic membranes, respectively. Peritrophic membranes are secreted by the anterior midgut epithelium mainly in a period between 2 and 4 h after feeding. Chitin or chitin precursors could be localized in vesicles and in the brush border of midgut cells, and in the peritrophic membranes, using colloidal gold labelled with wheat germ agglutinin. Two different textures of chitin-containing microfibrils were found in the peritrophic membranes, either a random or a hexagonal texture. The latter results if the microfibrils polymerize between the basal parts of the microvilli. Irregularities of the hexagonal texture can be correlated with an irregular pattern of the microvilli. In the posterior midgut peritrophic membranes with a random texture, chitin-containing microfibrils are continuously secreted in the form of patches.
    Materialart: Digitale Medien
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  • 8
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The nature of dark matter remains mysterious, with luminous material accounting for at most ∼25 per cent of the baryons in the Universe. We accordingly undertook a survey looking for the microlensing of stars in the Large Magellanic Cloud (LMC) to determine the fraction of Galactic dark ...
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    European journal of pediatrics 146 (1987), S. 123-127 
    ISSN: 1432-1076
    Schlagwort(e): Vitamin K deficiency ; Newborns ; Breast feeding ; Acarboxy-prothrombin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The incidence of acarboxy-prothrombin and the clotting activity of factors II and VII were evaluated on the fifth day of life in 183 healthy newborns, who had received no vitamin K prophylaxis. Acarboxy-prothrombin was detected in 93/183 newborns. All acarboxy-prothrombin-negative babies had factors II and VII clotting activities above 25% whereas a great variability was observed in acarboxy-prothrombin-positive babies: 21/93 had factor II and 14/93 had factor VII activities below 25%. Seventy-two of the acarboxyprothrombin-positive babies had normal factor II and VII clotting times on the fifth day of life. These babies must be suspected to have had vitamin K deficiency on one of the first 4 days, as acarboxy-prothrombin has a 50% disappearance rate of 50 h. Acarboxy-prothrombin ws mainly observed in breastfed infants (84/122) and only rarely detectable in infants receiving supplementary (7/44) or exclusive formula feeding (2/17). The type of milk feeding however might be less important for the babies' vitamin K supply than the actual milk intake. All acarboxy-prothrombin-positive babies had received small amounts of milk on the first 4 days of life. In those with low factor II and VII clotting activities the milk intake was low throughout the first 4 days of life, whereas babies with acarboxy-prothrombin and and normal clotting activities had increased their milk intake to more than 100 ml on the third and fourth day of life. Recommendations for vitamin K prophylaxis in newborns should be given with regard to the feeding on the first days of life.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Histochemistry and cell biology 93 (1989), S. 55-61 
    ISSN: 1432-119X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A plasma membrane glycoprotein (gp110) involved in cellular adhesion was studied in Wistar and Fischer rats. For quantitative analysis of the gp110 molecule a sandwich-ELISA was used. High quantities of gp110 were found especially in the liver, small intestine, submandibular gland and lung. The distribution and localization of the gp110 were investigated by immunohistochemistry utilizing soluble complexes of alkaline phosphatase and monoclonal anti-alkaline phosphatase antibodies. Immuno-reactivity was present in plasma membranes of vascular endothelial cells of some organs. Furthermore, immuno-staining also occurred in plasma membranes of lymphocytes, exocrine gland cells, excretory duct cells, hepatocytes, epithelial cells of the small intestine, kidney and vesicular gland and in the cytoplasm of renal connecting and collecting duct cells. The localization of gp110 in the luminal domain of the plasma membrane at many sites suggests that this glycoprotein is also involved in processes distinct from cell adhesion.
    Materialart: Digitale Medien
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