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  • 1
    Electronic Resource
    Electronic Resource
    Germ cell degeneration in normal and microwave-irradiated rats: Potential sperm production rates at different developmental steps in spermatogenesis (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 209 (1984), S. 501-507 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Germ cell degeneration in 14 normal and 14 microwave-irradiated, adult (400-500 gm), Sprague-Dawley rats was compared by evaluating potential sperm production rates at different developmental steps in spermatogenesis. Following 9 days of irradiation at 1.3 GHz (6 hours/day at 6.3 mW/gm using 1-μsec pulsewidth at 600 pulses/second) or sham treatment, rats were killed at 6.5, 13.0, 26.0, or 52.0 days following treatment. Testes were perfused with 2% glutaraldehyde, embedded in Epon, and sectioned at 0.5 μm for morphometric analyses. Plasma LH and FSH concentrations were determined by radioimmunoassay from blood collected on the day of death. Considering nuclear size, percentage of nuclei in the parenchyma, and life span of different cells, potential daily sperm production was determined for type B spermatogonia, preleptotene or pachytene primary spermatocytes, or spermatids with round nuclei. No differences (P 〉 .05) in parameters tested were found among time periods following irradiation. With the possible exception of sperm production per testis (P 〈 .05) based on pachytene spermatocytes, microwave irradiation had no effect on the parameters evaluated. No degeneration was detected in spermatogenesis when potential sperm production rates were determined either from type B spermatogonia to spermatids or from type B spermatogonia to a posttesticular approximation of sperm production rate. Thus, it appears that regulation of sperm production rates must take place during spermatogonial mitoses, since once the number of type B spermatogonia is determined, there is essentially no subsequent alteration in sperm production potential in normal or irradiated adult rats.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1092090410
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  • 2
    Electronic Resource
    Electronic Resource
    Effect of polymeric steric stabilizers on the settling of alumina (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 52 (1994), S. 997-1004 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The effect of polymeric steric stabilizers on the dispersion stability of alumina was determined by settling experiments. The theoretical settling density was determined for alumina in a 90:10 wt% toluene-ethanol mixed solvent. Polymers evaluated were sulfonated polystyrenes, Shell's functionalized Kraton block polymers (styrene-hydrogenated diene), ICI's polymeric surfactants, homopolystyrene, a nonfunctionalized Kraton block polymer, and two Union Carbide Corporation silwet surfactants. The high-molecular-weight sulfonated polystyrene (60,000) containing a low level of sulfonation, functionalized Kraton block polymers, and one ICI polymeric surfactant were effective in improving the dispersion stability of the alumina. The percent of theoretical settling density for the “good” polymeric steric stabilizers ranged from 45 to 50%. The low-molecular-weight sulfonated polystyrene (10,000 MW), homopolystyrene, unfunctionalized Kraton block polymer, one ICI polymeric surfactant, and the silwet surfactants were ineffective in improving the dispersion stability of the alumina in the mixed solvent. © 1994 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1994.070520718
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  • 3
    Electronic Resource
    Electronic Resource
    Photodegradative wavelength dependence of thermally resistant organic polymers (1969)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 13 (1969), S. 1825-1832 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The wavelength dependence of photodegradation of three “high temperature” aromatic polyamide polymers has been very accurately determined by means of a fast grating spectrograph used in conjunction with a high pressure xenon arc. One of these polymers, the poly-(isophthalamide) of 4,4′-bis(p-aminophenyl)-2,2′bithiazole, was found to be degraded significantly by visible light, especially that of 4140 Å, wavelength. Both the poly-terephthalamide of 1,3-bis(3-aminobenzamide) benzene and Du Pont Nomex, also an aromatic polyamide, were damaged primarily by radiation in the near ultraviolet region. Degradation band maxima for these polymers were observed at 3700 Å, and 3600 Å, respectively. All three thermally resistant polymers were thus found to be degraded by light of much longer wavelength than that which is harmful to other common polymers.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1969.070130902
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  • 4
    Electronic Resource
    Electronic Resource
    Novel gene exon homologous to pancreatic phospholipase A2: Sequence and chromosomal mapping of both human genes (1989)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 39 (1989), S. 327-337 
    Details
    ISSN: 0730-2312
    Keywords: phospholipase A2 ; human genes ; pancreatic ; human chromosome mapping ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: We described previously the cloning and DNA sequence of the human gene encoding pancreatic phospholipase A2 [DNA 5, 519]. When pancreatic phospholipase A2 (PLA2) cDNA was used to screen a human genomic library, two classes of clones were obtained. One class encoded the pancreatic enzyme, and a second class encoded one exon of an apparently related PLA2. No additional PLA2 gene exons displayed sufficient homology to be detected by the probe. A homologous sequence in both rat and porcine genomic DNA was detected by DNA blot hybridization, and the corresponding gene fragments were cloned and sequenced. Within the deduced amino acid sequences, the presence of known functional residues along with the high degree of interspecies conservation suggests the genes encode a functional PLA2 enzyme form. The encoded sequence lacks Cys11, as do the “type II” viperid venom and other nonpancreatic mammalian PLA2 enzymes. The sequence is distinct from porcine intestinal PLA2 and appears not to be a direct homolog of the recently published rabbit ascites and rat platelet enzymes. Hybridization of DNA probes containing sequences from these genes to genomic DNA blots of mouse/human somatic cell hybrids permitted chromosomal assignment for both. The pancreatic gene mapped to human chromosome 12, and the homologous gene mapped to chromosome 1.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240390312
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  • 5
    Electronic Resource
    Electronic Resource
    Zur Bestimmung der Kettenlänge in isoprenoid substituierten Chinonen (1960)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 43 (1960), S. 2088-2089 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The number of isoprene units in quinones with isoprenoid side chains is determined by quantitative NMR-spectrometry.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19600430726
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  • 6
    Electronic Resource
    Electronic Resource
    Ag-Sn-Hg alloys as electron compounds (1970)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 4 (1970), S. 269-274 
    Details
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: The extraordinary stability of the γ1 phase of dental amalgam was believed to indicate that part of the Sn in dental amalgam was contained in this phase. By extending the Hume-Rothery “electron compound” ideas to the three component Ag-Sn-Hg system, an estimate was made of the amount of Sn which could be held in the γ1 structure.A Ag-Sn alloy containing 9.1 weight per cent Sn was prepared, spheroidized, and sized. Portions were amalgamated and molded into tensile specimens, parts of which were subjected to X-ray diffraction, corrosion tests, and tests to determine amalgamation rate and dimensional changes during setting.X-ray diffraction patterns showed a complete absence of the γ2 phase, (thus indicating that all Sn was in the γ1 phase) and a stability intermediate between γ Ag-Hg and the γ1 phase of dental amalgam. Physical tests showed a low amalgamation rate, low 1-hr strength, high 7-day strength, and high corrosion resistance.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jbm.820040207
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  • 7
    Electronic Resource
    Electronic Resource
    The amount of tin in the γ1 phase of dental amalgam (1971)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 5 (1971), S. 239-244 
    Details
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Spherical-particle Ag-Sn alloy powders containing 4.3, 8.3, 12.0, 15.4, 18.5, 21.4, and 24.1 atomic per cent Sn were obtained. Amalgams from these alloys were examined by x-ray diffraction and metallography for the presence of the γ2 phase and the γ1 → β1 phase transformation. A single amalgam of the approximate composition of dental amalgam was prepared from a melt at high temperature and pressure and likewise examined.Results showed that the solubility of Sn in Ag-Hg is about 7 atoms of Sn per unit cell of the γ phase. As clinically prepared, the γ1 phase of dental amalgam contains, however, only about 5 atoms of Sn per unit cell. These 5 atoms, nevertheless, result in a very considerable stabilization of this phase due to the increase in its electron concentration.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jbm.820050310
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  • 8
    Electronic Resource
    Electronic Resource
    Corrosion under stress of materials composing dental amalgam (1969)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 3 (1969), S. 569-576 
    Details
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Corrosion potentials of materials composing dental amalgam have been measured in artificial saliva as the specimens were subjected to an increasing tensile load. Further, tensile tests have been carried out on specimens which had been previously subjected to controlled corrosion.The corrosion potentials of Cu, Ag, Zn, Ag2Hg3, Ag3Sn and finished dental amalgam showed only a slight increase in the anodic direction as the load increased. The potentials of Sn and Sn amalgams, on the other hand, showed a considerable increase.Most of the above results were explained as being a consequence of the rupture and repair of protective films as stress was applied or released. For Sn, however, it was necessary to postulate a complex attack by the corrodant to explain the large potential change.Of the phases of dental amalgam whose tensile strengths were measured after subjection to controlled corrosion, only the γ2 or Sn-Hg phase was affected. Its strength was lowered by corrosion, whether or not stress was applied.It was concluded that stress, as such, probably is not a direct factor in the corrosion of dental amalgam under oral conditions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jbm.820030403
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  • 9
    Electronic Resource
    Electronic Resource
    Progress in splat-cooling of dental alloys (1977)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 11 (1977), S. 483-488 
    Details
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Improved techniques in preparing and sizing dental alloy powders containing Ag, Sn, and Cu have led to amalgams with higher strengths and less spread in dimensional change but very poor shelf life. Since maximum strengths occurred for amalgams containing about 15% more Sn than previously reported, and consequently presumably more of the weak γ2 phase, the higher strengths are difficult to understand.The poor shelf life may be explained by oxidation of the highly reactive splatcooled alloy or possibly by the existence of highly reactive metastable phases which transform fairly rapidly to the less reactive equilibrium ones.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jbm.820110404
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  • 10
    Electronic Resource
    Electronic Resource
    Inhibition of low density lipoprotein uptake in confluent endothelial cell monolayers correlates with a restricted surface receptor redistribution (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 100 (1979), S. 481-495 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Binding of either low density lipoprotein (LDL) or Concanavalin A (ConA) to actively growing vascular endothelial cells is associated with a redistribution of the appropriate cell surface receptor sites which form patches and caps. This receptor lateral mobility is greatly restricted when endothelial cells reach confluence and adopt the configuration of a cell monolayer composed of closely apposed and non-overlapping cells. In this case, although the cells still exhibit specific LDL binding to the appropriate cell surface receptor sites, neither the binding of LDL nor of ConA induces a receptor redistribution. The lack of LDL receptor redistribution correlates with a marked decrease in the rate of LDL internalization. In contrast, no such a density-dependent changes are observed in cell types which grow on top of each other and form multiple cell layers at confluence. Thus, neither LDL nor ConA induced cap formation in either sparse or confluent smooth muscle cell cultures and the same rate of LDL internalization is observed at both cell densities. Similarly, adsorptive endocytosis of cationized LDL (which enters the cell independently of the LDL receptor sites) was not correlated with a detectable receptor redistribution, nor was it significantly affected by changes in cell density and spatial organization.The formation of a confluent cell monolayer resting on an underlying basement membrane might therefore provide, via a change in membrane dynamics, a mechanism whereby the endothelium of large blood vessels can function as a protective barrier against the high circulating levels of LDL in plasma.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041000311
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