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
    A microspectrophotometric analysis of the effect of fluoride on immature enamel matrix protein of rat molar teeth (1980)
    Springer
    Calcified tissue international 30 (1980), S. 57-66 
    Details
    ISSN: 1432-0827
    Keywords: Dental enamel ; Sodium fluoride ; Microspectrophotometry ; Enamel matrix protein ; Amelogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Over a 24-h period, Wistar rats from 4 litters, 6 to 9 days old, were given five intraperitoneal injections of a solution of 0.9% sodium chloride containing sodium fluoride (3 mg F/kg body weight). Within-litter controls were used. All rats were killed by decapitation 2 h after the final injection and the rat heads, cut sagittally, were processed for protein histochemistry. The intensity of staining of the protein in the enamel matrix of the upper jaw molar tooth buds was quantified using the two-wavelength method of microphotometry. A significant increase in the intensity of staining of fluoride-treated tissues over controls was observed with the histochemical methods specific for arginine (P〈0.01), tyrosine (P 〈 0.05), and cysteine (P〈0.05). Other histochemical methods specific for amino acid groups failed to show any significant difference between fluoride and non-fluoride-treated enamel matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02408607
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ameloblast apoptosis and IGF-1 receptor expression in the continuously erupting rat incisor model (1999)
    Springer
    Apoptosis 4 (1999), S. 441-447 
    Details
    ISSN: 1573-675X
    Keywords: ameloblasts ; amelogenesis ; apoptosis ; insulin-like growth factor.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Enamel-producing cells (ameloblasts) pass through several phenotypic and functional stages during enamel formation. In the transition between secretory and maturation stages, about one quarter of the ameloblasts suddenly undergo apoptosis. We have studied this phenomenon using the continuously erupting rat incisor model. A special feature of this model is that all stages of ameloblast differentiation are presented within a single longitudinal section of the developing tooth. This permits investigation of the temporal sequence of gene and growth factor receptor expression during ameloblast differentiation and apoptosis. We describe the light and electron microscopic morphology of ameloblast apoptosis and the pattern of insulin-like growth factor-1 receptor expression by ameloblasts in the continuously erupting rat incisor model. In the developing rat incisor, ameloblast apoptosis is associated with downregulated expression of the insulin-like growth factor-1 receptor. These data are consistent with the hypothesis that ameloblasts are “hard wired” for apoptosis and that insulin-like growth factor-1 receptor expression is required to block the default apoptotic pathway. Possible mechanisms of insulin-like growth factor-1 inhibition of ameloblast apoptosis are presented. The rat incisor model may be useful in studies of physiological apoptosis as it presents apoptosis in a predictable pattern in adult tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009600409421
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Kinetics of anionic copolymerization. Determination of absolute rate constants (1962)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 61 (1962), S. 31-37 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Lack of termination in the “Living” polymer systems enables one to determine directly the absolute rate constant of propagation and of copolymerization. Anionic polymerizations in tetrahydrofuran are usually very fast, and a flow technique was developed to determine the rate of these reactions. The method is described and its use illustrated by studies on the following systems: styrene-p-methylstyrene, styrene-p-methoxystyrene, and styrene-2-vinylpyridine. The results indicate that the polarity of the reacting monomer is the dominant factor in determining the value of the copolymerization rate constant as long as the polarities of the monomers involved are similar. However, the results obtained on the system styrene-2-vinylpyridine clearly demonstrate that the terminal carbanion plays a major role when the polarities of the two monomers are very different. The technique can also be used to study the effect of the penultimate unit of a chain on the rate constant of propagation or copolymerization. Moreover, the chain length of the “living” polymer can be caried and its effect of the rate constant determined.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1962.1206117106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The effect of monomer concentration on the rate of anionic polymerization of styrene in tetrahydrofuran (1967)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 108 (1967), S. 288-291 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1967.021080125
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Copolymerization of butadiene, isoprene, and 2,3-dimethyl butadiene with living polystyrene. Electron-donating effect of methyl group (1964)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Letters 2 (1964), S. 735-737 
    Details
    ISSN: 0449-2986
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1964.110020715
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The absolute rate constant of propagation of the free living polystyrene ion, and the dissociation constant of the ∼∼S-, NA+ ion pair (1965)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Letters 3 (1965), S. 1037-1041 
    Details
    ISSN: 0449-2986
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1965.110031212
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Anionic polymerization of vinylmesitylene (1965)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A: General Papers 3 (1965), S. 3099-3106 
    Details
    ISSN: 0449-2951
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Anionic polymerization of vinylmesitylene was investigated in THF (counterion Na+) at temperatures ranging from +25° to -70°C. The homopropagation is slow (kp ∼ 11./mole-sec. at 25°C.), indicating the basically low reactivity of the monomer. Studies of conductivity and the retardation of the polymerization by the addition of Na+BPh4- demonstrate that free ions and ion pairs participate in the process. At 25°C. the kp of the free ion appears to be about 1000 times greater than that of ion pair. The outstanding feature of the polymerization is the proton transfer from the monomer to living end, producing an inert ion (or its isomer) which does not propagate. This reaction leads to retardation of the polymerization. Its contribution decreases on lowering the temperature, and the effect of Na+BPh4- indicates that the free ion, and not the ion-pair, acts as a base in the proton transfer.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1965.100030905
    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...