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11.
Barnes I 《Science (New York, N.Y.)》1970,168(3934):973-975
Waters unusually rich in ammonia, boron, carbon dioxide, hydrogen sulfide, and hydrocarbons are found in more than 100 localities along the Pacific coast of the United States. The waters are believed to be products of low-grade metamorphism of marine sediments. The marine sedimentary rocks would have to be tectonically emplaced below crystalline rocks in many places. Mercury ore deposits are probably also products of the low-grade metamorphism. 相似文献
12.
Induced (traumatic) resin in white spruce (Picea glauca (Moench) Voss) leaders resistant or susceptible to the white pine weevil (Pissodes strobi Peck) was analyzed for volatile terpenes and diterpene resin acids after simulated white pine weevil damage. Leaders from 331 trees were wounded just below the apical bud with a 1-mm diameter drill, coinciding with the natural time of weevil oviposition in the spring. Leaders were removed in the fall, and the bark and xylem from the upper and lower regions of the leader extracted and analyzed by gas chromatography. Unwounded trees had low amounts of resin in xylem compared with bark. In response to wounding, volatile terpenes and diterpene resin acids increased in the upper xylem (area of wounding), with resistant trees showing a greater increase than susceptible trees. Wounding caused monoterpenes in particular to decrease in the lower region of the leader (away from the drilled area) in greater amounts in susceptible trees than in resistant trees. In response to wounding, the proportion of monoterpene to resin acid increased in the upper and lower xylem of resistant trees, and slightly increased in the upper xylem of susceptible trees. Monoterpene-enriched resin is more fluid than constitutive resin, and probably flows more readily into oviposition cavities and larval mines, where it may kill immature weevils. Loss of resin components in the lower xylem suggested catabolism and transport of these materials to the site of wounding; however, energetic and regulatory data are necessary to confirm this hypothesis. This study provides a basis for measuring the ability of a tree to undergo traumatic resinosis that could be used to screen for resistance to white pine weevil. 相似文献
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The effect of boiling and baking in either a convential or microwave oven on the lipid content of potatoes was investigated. The crude lipid content of potatoes was lowered significantly by all methods of cooking. The loss was highest in potatoes cooked in a microwave oven, least in boiled tubers, and intermediate in tubers baked in a conventional oven. Similar trends were observed for both cortex and pith tissues. Generally, the phospholipid content followed the same trend as the crude lipid, the exception being the cortex tissue of tubers baked in the conventional oven, in which the greatest loss of phospholipid occurred. Cooking did not significantly alter the fatty acid composition of tubers. A possible relationship between the degree of cell rupturing, known to be influenced by different mechanisms of heat transfer, and the amounts of tuber lipid associated with different cooking methods was discussed. 相似文献
15.
Lansing AI 《Science (New York, N.Y.)》1947,106(2748):187-188
16.
A synthetic hexaploid, Triticum timofeevii×T. tauschii, was used to transfer disease resistance genes to the commercial cultivar Saratovskaya 29 (S29) by backcrossing. After five backcrosses the resulting derivatives still showed some traits of the synthetic, namely brown spike glumes and several gliadin components. Genetic analysis showed that the derived forms had inherited the Gli-D1 allele of the synthetic, which was found to be tightly linked to a gene for glume colour. Recombination percentages between these genes was estimated to be 2.5 ± 1.7%. The development of the derivatives was also accompanied by a rearrangement within the Gli-B1 locus, resulting in the formation of a new variant of the allele in S29. 相似文献
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18.
C L Sillerud R F Bey M Ball S I Bistner 《Journal of the American Veterinary Medical Association》1987,191(12):1576-1578
After the observation of 2 horses with uveitis on a horse farm in the Minnesota River valley, 100 horses from this geographic area were given ophthalmologic examinations and were evaluated serologically for leptospirosis. A statistically significant (P less than 0.001) association was observed between the finding of antibodies against Leptospira interrogans serovar pomona and uveitis. 相似文献
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20.
G K Ogilvie C S Brunkow G B Daniel W M Haschek 《Journal of the American Veterinary Medical Association》1989,194(6):793-796
Malignant lymphoma involving bone and heart was diagnosed in a 4-year-old Whippet, using radiography, histologic examination, nuclear scintigraphy of the skeleton and heart, and cardiac ultrasonography. 相似文献