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151.
Schellander K Peli J Kneissl F Schmoll F Mayr B 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1994,111(1-6):162-166
SUMMARY: Polymorphism in the second intron of the porcine growth hormone gene of 273 Austrian Landrace and 81 Austrian Edelschwein pigs was investigated with a PCR-RFLP-technique. Results showed significantly different genotype patterns between the two breeds. The frequency of the Hae II(-) allele was significantly (P < 0,001) higher in the landrace than in the Edelschwein population (0,83 and 0,47 resp.). The Msp I(+) allele was predominant in both breeds but signifanctly higher in the Landrace (0,98 versus 0,69; P < 0,01). Analyses the Hae II/Msp I locus combination revealed also in breed specific difference. In the Landrace a very low interaction was found between the Hae II and ryr 1 locus, and between Msp I and ryr 1 locus (c. c. = 0,181 and 0,186 resp.). The correlation was slightly stronger (c. c. = 0,266) between the ryr 1 and Hae II/Msp I genotypes. No correlation was detected among the three loci in the Edelschwein population. ZUSAMMENFASSUNG: Variabilit?t des Somatotropin Gens in ?sterreichischen Schweinerassen genotypisiert hinsicbtlich ryr 1 An 273 ?sterreichischen Landrasse Schweinen und 81 ?sterreichischen Edelschweinen wurde der Polymorphismus am zweiten Intron des Schweinewachstumshormons mittels PCR-RFLP-Technik untersucht. Genotypen-und Genfrequenzen waren zwischen den beiden Rassen signifikant verschie- den. Die Hae II(-) Allelfrequenz war bei den Landrassetieren signifikant h?her (P < 0,001) als bei den Edelschweinen (0,83 bzw. 0,47). In beiden Rassen überwiegte das Msp I(+) Allel, das aber signifikant ?fters bei der Landrasse auftrat (0,98 bzw. 0,69; P < 0,01). Die Verteilung der Locuskombination von Hae II/Msp I zwischen den beiden Rassen war ebenfalls unterschiedlich. Bei der Landrasse konnte nur ein sehr geringer Zusammenhang zwischen dem Hae II und ryr 1 Locus (c. c. = 0,181 bzw. 0,186) und auch zwischen dem Msp I und ryr 1 Locus festgestellt werden. Die Korrelation zwischen dem ryr 1 und Hae II/Msp I Genotyp war geringfügig gr??;er (c. c. = 0,266). Bei den Edelschweinen konnte kein Zusammenhang zwischen den drei untersuchten Loci festgestellt werden. 相似文献
152.
Wuethrich B 《Science (New York, N.Y.)》1994,265(5180):1802-1803
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Sabel BA 《Science (New York, N.Y.)》1993,260(5115):1753-1758
155.
Ants of the ponerine genus Odontomachus use a trap jaw mechanism when hunting fast prey. When particular trigger hairs, located on the inner edge of the mandibles, are touched by prey, the jaws close extremely rapidly and trap the target. This trap jaw response lasts only 0.33 to 1 millisecond. Electrophysiological recordings demonstrated that the trigger hairs function as mechanoreceptors. Associated with each trigger hair are large sensory cells, the sensory axons of which measure 15 to 20 micrometers in diameter. These are among the largest sensory neurons, and their size implies that these axons conduct information very rapidly. 相似文献
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Shortleaf pine (Pinus echinata Mill.) seedlings in 24 open-top chambers were exposed to combinations of ozone (carbon-filtered (control), ambient, 1.7 x ambient, and 2.5 x ambient) and acidic precipitation (pH 5.3, 4.3 and 3.3) for 16 months (1989 harvest) or 28 months (1990 harvest). Although the effects of acid rain were generally not significant, there was a trend toward increased aboveground biomass and leaf area in seedlings subjected to the low pH treatments. Because N concentrations in the soils generally increased with decreasing pH, we concluded that the effects of acid rain on aboveground biomass and leaf area were a consequence of an increasing concentration of soil N. In the 1989 harvest, seedlings in the 2.5 x ambient ozone treatment had significantly less biomass in all aboveground plant components and significantly less total leaf area than seedlings in the 1.7 x ambient ozone treatment. In the 1990 harvest, there were no significant effects of ozone on total aboveground biomass, although there was a trend toward reduced biomass in seedlings in the 2.5 x ambient ozone treatment. Both total leaf area and leaf biomass were significantly less in seedlings exposed to 2.5 x ambient ozone for 28 months than in both control seedlings and seedlings in the 1.7 x ambient ozone treatment. The greater, but not always significant, aboveground biomass and leaf area of seedlings in the 1.7 x ambient ozone treatment compared with control seedlings may be associated with the observed increase in soil nitrate concentration as a result of increased rates of leaf senescence and litterfall. 相似文献
160.