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
    Assessment of Amyloid β Protein in Cerebrospinal Fluid as an Aid in the Diagnosis of Alzheimer's Disease (1996)
    Oxford, UK : Blackwell Science Ltd
    Journal of neurochemistry 66 (1996), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: The principal constituent of amyloid plaques found in the brains of individuals with Alzheimer's disease (AD) is a 39–42-amino-acid protein, amyloid β protein (Aβ). This study examined whether the measurement of Aβ levels in CSF has diagnostic value. There were 108 subjects enrolled in this prospective study: AD (n = 39), non-AD controls (dementing diseases/syndromes; n = 20), and other (n = 49). CSF was obtained by lumbar puncture, and Aβ concentrations were determined using a dual monoclonal antibody immunoradiometric sandwich assay. The mean Aβ value for the AD group (15.9 ± 6.8 ng/ml) was not significantly different from that for the non-AD control group (13.0 ± 7.1 ng/ml; p = 0.07), and substantial overlap in results were observed. Aβ values did not correlate with age (r = −0.05, p = 0.59), severity of cognitive impairment (r = 0.22, p = 0.21), or duration of AD symptoms (r = 0.14, p = 0.45). These findings are in conflict with other reports in the literature; discrepant results could be due to the instability of Aβ in CSF. Aβ immunoreactivity decays rapidly under certain conditions, particularly multiple freeze/thaw cycles. Use of a stabilizing sample treatment buffer at the time of lumbar puncture allows storage of CSF without loss of Aβ reactivity. In conclusion, the total CSF Aβ level is not a useful marker for current diagnosis of AD.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1471-4159.1996.66010259.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
    Evolution of ion internal energy during collisional excitation in the Paul ion trap: A stochastic approach (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 2214-2221 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A first-order model is developed for collisional activation as effected via resonance excitation and helium buffer gas in the Paul ion trap. For an ion population at steady-state under specified experimental conditions, the kinetic theory of ion transport in gases is first used to calculate an effective temperature shown to be identical to the internal temperature for molecular ions in an atomic gas. The evolution of the ion internal energy is then followed by a random walk simulation designed to be representative of the actual collisional energy transfer process, except ion losses due to dissociation and reactive processes during collisional activation are excluded. During the simulation, inelastic ion-neutral collisions increase the average ion internal energy via small energy changes (both positive and negative) until a steady-state condition is reached in which excitation and deexcitation processes are balanced. Histogramming the simulated data reveals a Boltzmann-type internal energy distribution whose average internal energy is the same as that calculated for a true Boltzmann distribution at the same internal temperature. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471812
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Competitive gettering of copper in Czochralski silicon by implantation-induced cavities and internal gettering sites (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 69 (1996), S. 3060-3062 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effectiveness of copper gettering by implantation-induced cavities in competition with internal gettering sites in silicon was demonstrated. The cavities were formed in the near surface region by He implantation and annealing while the internal gettering sites were created in the material's bulk by a ramped hi–lo–hi oxygen precipitation heat treatment. Ion implantation was used to controllably introduce the copper. The quantity of implanted copper was below that corresponding to saturation of solution throughout the wafer at the gettering temperatures of 700 and 800 °C. The cavities were found to be an effective gettering site in the presence of internal gettering sites with only a small amount of copper being gettered at the internal gettering sites. These results have important implications for optimal gettering of metallic impurities from integrated circuit device regions. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.116839
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Radiative and nonradiative decay of electronically excited NCO (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 8279-8291 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A study to observe higher vibrational levels in NCO(A˜ 2Σ+) and the onset of predissociation in this molecule has been carried out. Laser fluorescence spectra have been recorded over the wave number range 27 300–32 900 cm−1, from the A˜(0,0,2)–X˜(0,0,0) band up through the B˜(1,0,0)–X˜(0,0,0) band. Vibrational assignments have been made for a number of newly observed A˜–X˜ bands, and band origin wave numbers and upper level rotational constants have been derived from comparison of experimental spectra with simulations. Decay lifetimes for excitation of a large number of both assigned and unassigned excited vibronic levels have been determined. The onset of predissociation appears to occur at energies slightly below that of the B˜(0,0,0) level. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471580
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    PROPOSAL FOR A PATHOGENESIS-BASED CLASSIFICATION OF TUMORAL CALCINOSIS (1996)
    Oxford, UK : Blackwell Publishing Ltd
    International journal of dermatology 35 (1996), S. 0 
    Details
    ISSN: 1365-4632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background. Deposition of calcium in skin is currently categorized into a group of disorders referred to as calcinosis cutis. Divisions between types and subtypes within this confusing classification are predominantly based on morphologic differences in the calcification and serve to obscure pathogenesis. This is especially evident in a subtype of calcinosis cutis, known as tumoral calcinosis. Calcifications in cases of tumoral calcinosis share the following characteristics, but without evidence of a common pathogenesis: large size, juxtaarticular location, progressive enlargement over time, a tendency to recur after surgical removal, and an ability to encase adjacent normal structures. The goal of this study was to formulate a pathogenesis-based classification for cases of tumoral calcinosis. Methods. In a literature review 121 cases of tumoral calcinosis were identified. These cases, along with a case evaluated in our clinic, were reviewed retrospectively, and their features compared. Results. Analysis suggests three pathogenetically distinct subtypes of tumoral calcinosis: (1) Primary normophosphatemic tumoral calcinosis: patients have normal serum phosphate, normal serum calcium, and no evidence of disorders previously associated with soft tissue calcification; (2) primary hyperphosphatemic tumoral calcinosis: patients have elevated serum phosphate, normal serum calcium, and no evidence of disorders previously associated with soft tissue calcification; and (3) secondary tumoral calcinosis: patients have a concurrent disease capable of causing soft tissue calcification. Justification for this classification is based on the presence or absence of disorders known to promote soft tissue calcification and statistically significant differences in family history, mean calcification number, mean serum phosphate level, and calcification recurrence after excision. Conclusions. A classification for tumoral calcinosis is devised that outlines potential pathogenetic mechanisms and predicts response to therapy and prognosis. Analysis of other forms of calcinosis cutis may reveal definable pathogenetic differences that suggest a coherent classification for all cutaneous calcinoses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-4362.1996.tb02999.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
    EXPERIMENTAL STUDIES OF RESONANCES IN UNIMOLECULAR DECOMPOSITION (1996)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Physical Chemistry 47 (1996), S. 495-525 
    Details
    ISSN: 0066-426X
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Chemistry and Pharmacology , Physics
    Notes: Abstract In recent years we have witnessed tremendous progress in our understanding of unimolecular reactions on a fully state-resolved level. Here we describe recent state-resolved experimental studies of resonances in unimolecular reactions, focusing on the transition from isolated to overlapping resonances. Depending on the well depth and extent of intramolecular vibrational energy redistribution, the resonances can exhibit properties ranging from mode- and state-selective to statistical behavior. In the statistical limit the resonances are usually overlapped, and interference effects may become prominent. We use recent studies of HCO, HFCO, and CH3O to examine the transition from mode-selective to statistical behavior in the isolated regime. Experimental and theoretical studies of NO2, including photofragment yield spectra, fully resolved NO quantum state distributions, and decomposition rates are used to examine unimolecular decomposition in the regime of overlapping resonances.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.physchem.47.1.495
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    GENETICALLY ENGINEERED SYNTHESIS OF NATURAL PRODUCTS: From Alkaloids to Corrins (1996)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Microbiology 50 (1996), S. 467-490 
    Details
    ISSN: 0066-4227
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Biology
    Notes: Abstract Because many natural products are of biological and medicinal importance, methods are continually being sought for studying their biosynthetic pathways, which may eventually result in increased production and the generation of novel compounds. Advances in genetic engineering have enabled the homologous or heterologous expression of many natural product biosynthetic genes from divergent sources, resulting in a supply of enzymes not readily available by isolation from the producing organism. Mixing and matching of these enzymes in cell-free reactions can provide information, not available by any other means, about enzyme mechanisms, pathway intermediates, and possible variations in the structure of the final product.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.micro.50.1.467
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    REGION OF INFLUENCE REGRESSION FOR ESTIMATING THE 50-YEAR FLOOD AT UNGAGED SITES (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 32 (1996), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : Five methods of developing regional regression models to estimate flood characteristics at ungaged sites in Arkansas are examined. The methods differ in the manner in which the State is divided into subregions. Each successive method (A to E) is computationally more complex than the previous method. Method A makes no subdivision. Methods B and C define two and four geographic subregions, respectively. Method D uses cluster/discriminant analysis to define subregions on the basis of similarities in watershed characteristics. Method E, the new region of influence method, defines a unique subregion for each ungaged site. Split-sample results indicate that, in terms of root-mean-square error, method E (38 percent error) is best. Methods C and D (42 and 41 percent error) were in a virtual tie for second, and methods B (44 percent error) and A (49 percent error) were fourth and fifth best.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1996.tb03444.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Temperature-dependent regulation of Yersinia enterocolitica Class III flagellar genes (1996)
    Oxford BSL : Blackwell Science Ltd
    Molecular microbiology 19 (1996), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Temperature is a key environmental cue for Yersinia enterocolitica as well as for the two other closely related pathogens, Yersinia pestis and Yersinia pseudotuberculosis. Between the range of 30°C and 37°C, Y. enterocolitica phase-varies between motility and plasmid-encoded virulence gene expression. To determine how temperature regulates Y. enterocolitica motility, we have been dissecting the flagellar regulatory hierarchy to determine at which level motility is blocked by elevated temperature (37°C). Here we report the cloning, DNA sequences, and regulation of the two main regulators of Class III flagellar genes, fliA (σF) and flgM (anti-σF), and a third gene, flgN, which we show is required for filament assembly. Identification of the Y. enterocolitica fliA and flgM genes was accomplished by functional complementation of both S. typhimurium and Y. enterocolitica mutations and by DNA sequence analysis. The Y. enterocolitica fliA gene, encoding the flagellar-specific σ-factor, σF, maps immediately downstream of the three flagellin structural genes. The flgM and flgN genes, encoding anti-σF and a gene product required for filament assembly, respectively, map downstream of the invasin (inv) gene but are transcribed in the opposite (convergent) direction. By using Northern blot analyses we show that transcription of both fliA and flgM is immediately arrested when cells are exposed to 37°C, coincident with the timing of virulence gene induction. Unlike S. typhimurium flgM− mutants, Y. enterocolitica flgM− mutants are fully virulent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.1996.452978.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Localization of ethylene biosynthesis in roots of sunflower (Helianthus annuus) seedlings (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 96 (1996), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Sunflower (Helianthus annuus L.) seedlings were grown in aeroponic chambers which allowed for easy access to and easy harvesting of undamaged roots. In different portions of these roots we followed the rate of ethylene production, levels of 1-aminocyclopropane-1-carboxylic acid (ACC), N-malonyl-ACC and ACC oxidase mRNA and activity of ACC oxidase. ACC oxidase was measured with an in vitro assay, ACC and N-malonyl-ACC by selected ion monitoring gas chromatography-mass spectrometry. Ethylene production was highest in the tip of the root and tower in the middle and basal (part nearest the hypocotyl) portions of the root. The levels of ACC and ACC oxidase mRNA mirrored the levels of ethylene production. The lowest quantities of N-malonyl-ACC were found in the root tips. Upon gentle transfer of seedlings from an aeroponic system to treatment tubes, ACC content transiently increased; the greatest increase occurred in the tips. This brief rise in ACC content was not correlated with an increase in ethylene production. ACC oxidase activity was lowest in the tip and higher in the middle and base; the opposite of the pattern of ethylene production. Treating the seedlings with ACC produced a rapid rise in ACC content and ethylene production and inhibited root elongation. ACC oxidase activity was not induced by ACC treatment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1399-3054.1996.tb00180.x
    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...