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371.
A Proteus inconstans which Produces 'Cabbage Odour' in the Spoilage of Vacuum-packed Sliced Bacon 总被引:1,自引:1,他引:0
The isolation and identification of a species of Proteus inconstans capable of producing 'cabbage odour' spoilage of sliced vacuum-packed bacon are described. Gas chromatographic-mass spectrometric analysis indicated that the odoriferous compound was methane thiol. Data are presented on the effect of the pH and salt level on the growth of the organism in laboratory media and the production of methane thiol in bacon. 相似文献
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G. A. GARDNER 《Journal of applied microbiology》1980,48(1):69-74
Pseudomonas spp. in Wiltshire bacon cover brines taken from seven bacon factories were enumerated at regular intervals over six months. There were differences between factories as assessed by the geometric mean counts (12–2907/ml) or by the percentage of samples exceeding 103 /ml (0–75%). Heavy pseudomonad contamination of brines was associated with large populations of Pseudomonas spp. on fresh pork carcasses and vice versa. The curing of defrosted pork carcasses also led to high Pseudomonas spp. counts in brines. The average time for 90% reduction in a Pseudomonas population in brine was 35 d. These data can aid interpretation of the Pseudomonas count of bines when it is used as a part of microbiological quality control. A set of advisory standards proposed. 相似文献
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RANDALL T. SCHUH GARY M. STONEDAHL 《Cladistics : the international journal of the Willi Hennig Society》1986,2(3):337-355
Abstract— The history of biogeographic theories about the Indo-Pacific is reviewed. The methods of cladistic biogeography are introduced and 10 monophyletic groups of Miridae (Insecta: Heteroptera) are used to apply these methods in the Indo-Pacific. The results are summarized and then combined with those of Duffels on cicadas. The results of most previous schemes are rejected on the basis of new results because the prior studies applied methods which failed to correctly interrelate areas of endemism within the Indo-Pacific and between this and other regions. The composite biotic nature of New Guinea is stressed.
"it is the presence in and not the absence from land areas of organisms that calls for reasoned explanations" (Evans, 1959) 相似文献
"it is the presence in and not the absence from land areas of organisms that calls for reasoned explanations" (Evans, 1959) 相似文献
378.
PATRICK K. DEVERS DEAN F. STAUFFER GARY W. NORMAN DAVE E. STEFFEN DARROCH M. WHITAKER JEFFREY D. SOLE TOM J. ALLEN STEVE L. BITTNER DAVID A. BUEHLER JOHN W. EDWARDS DANIEL E. FIGERT SCOTT T. FRIEDHOFF WILLIAM W. GIULIANO CRAIG A. HARPER WILLIAM K. IGO ROY L. KIRKPATRICK MICHAEL H. SEAMSTER HARRY A. SPIKER Jr. DAVID A. SWANSON BRIAN C. TEFFT 《野生动植物专论》2007,168(1):1-36
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Role of Copper Binding, Absorption, and Translocation in Copper Tolerance of Agrostis gigantea Roth 总被引:3,自引:0,他引:3
The capacity of roots to accumulate and retain copper was examinedin two clones of Agrostis gigantea which differ in their toleranceto excess copper. Root elongation growth in the non-tolerantclone was completely inhibited by 16 mmol m3 Cu whereas40 mmol m3 was required for inhibition in the tolerantclone. The amount of readily exchangeable copper was greaterin roots of the tolerant clone than in the non-tolerant clone.The higher capacity for binding copper did not prevent the entryof copper into the cells of intact or excised roots of the tolerantclone. Roots of both clones contained similar amounts of copperafter removal of the readily exchangeable fraction. More copperwas translocated to the shoots of the tolerant than the non-tolerantclone. The explanation of copper tolerance in Agrostis giganteamust be sought in areas other than those of differences in grosscopper absorption and retention by roots. 相似文献