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81.
W. Meyer A. Schnapper G. Hülmann H. Seger 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(4):281-283
Based on a computer‐assisted method and regression analysis, several structural parameters of the hair cuticula pattern of primary hairs of 94 wild mammals and 44 breeds of 10 domesticated mammals were evaluated and compared between both groups. Biologically relevant relationships between the parameters examined could only be obtained for the wild animals. In this way domestication‐induced defects became evident for the hair cuticula pattern that is a typical structural feature of the hair shaft. 相似文献
82.
Jean P. Rouchaud Georges J. Lhoest Michel J. Mercier Joseph A. Meyer 《Pest management science》1977,8(1):23-30
The metabolism of benomyl was studied in carrots treated with high rates of benomyl, and in strawberries and apples treated at normal rates. The same metabolites were observed in both cases though, at normal rates, their concentrations were low but significant. Detected by means of gas-liquid chromatography they were: carbendazim, 2-aminobenzimidazole (2-AB), benzimidazole, 2-aminobenzonitrile, o-phenylene-diamine and the conjugates of carbendazim and 2-AB. o-Phenylenediamine has not hitherto been reported as a metabolite of benomyl. Two unidentified compounds were also observed by gas-liquid chromatography; their mass spectra were obtained by means of combined gas-liquid chromatography and mass spectrometry. 相似文献
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84.
Summary Up till now numerical taxonomy has been applied to cultivated plants only to a limited extent though this method seems to be especially suitable for handling the great diversity of these plants. Moreover the theory of numerical taxonomy has not been studied sufficiently.Therefore studies with cultivated plants were begun with the aim to investigate the fitness of different numerical taxonomic techniques for their classification. Materials used: 1) 24 species ofTriticum and additionally 24 species ofAegilops 2) 1225Triticum taxa from Iran (mostlyT. aestivum) 3) 312 taxa ofPisum (mostlyP. sativum).Using 10 coefficients and 7 clustering methods inTriticum andAegilops in most cases a clear separation of both genera resulted as well as a species arrangement withinTriticum according to the genomes.The main aim when dealing with the wheat from Iran was the investigation of the influence of different character sets. At this the coefficient ofGower and the unweighted pair-group method using arithmetic averages (UPGMA) were applied. The separation of the different species is satisfying clear while the representatives of the different varieties ofT. aestivum could not always be found in one cluster. This effect increased when adding further characters sets.InPisum the influence of 11 similarity coefficients to the dendrogram formation has been investigated. With two-state characters the simple matching coefficient and with mainly multistate characters the Canberra metric gave best results (using UPGMA and information measures SUMRAT and SAMRAT).The hitherto existing results show the complicatedness of the evaluation of numerical taxonomic methods in their application to cultivated plants. Therefore generalizations are not yet possible.
Numerisch-taxonomische Studien in den GattungenTriticum L. undPisum L.相似文献
85.
Svetlana Milija?evi?-Mar?i? Biljana Todorovi? Ivana Poto?nik Milo? Stepanovi? Emil Rekanovi? 《Phytoparasitica》2012,40(3):299-303
Symptoms of brown blotch were observed on cultivated Agaricus bisporus on several mushroom farms in Serbia. Subsequently, samples were collected from nine localities during 2006?C2010 and fluorescent Gram-negative bacterial strains were isolated. All strains caused sunken brown lesions on A. bisporus tissue blocks after artificial inoculation. Isolated strains showed the LOPAT characteristics of the group Va being negative for levan production; the ability to produce a hypersensitivity reaction in tobacco; were oxidase and arginine dihydrolase positive; and lacked pectolytic activity. The results from other tests were as follows: oxidative metabolism of glucose; catalase activity positive; aesculin hydrolisis negative; Tween 80 hydrolysis positive; casein hydrolysis positive; gelatine hydrolysis and nitrate reduction negative; mannitol, erythritol, sorbitol, inositol and trehalose were used as a carbon source but not sucrose, arabinose and D(-) tartrate. Based on these features bacterial strains were identified as Pseudomonas tolaasii. The identity of isolated strains was confirmed by polymerase chain reaction. This is the first report of P. tolaasii in Serbia. 相似文献
86.
Stemme K Meyer U Flachowsky G Scholz H 《Journal of animal physiology and animal nutrition》2006,90(3-4):173-176
In the experiment the influence of an elevated oral cobalt supply (Co content in the ration 0.27 mg Co/kg DM; supplement of 0.14 mg Co/kg DM as CoSO(4)) to pregnant dairy cows on the vitamin B(12) concentration in milk, colostrum and vitamin B(12) status of their calves was tested in comparison with unsupplemented controls (0.13 mg Co/kg DM). While there was no significant difference in vitamin B(12) concentration in the at 70th day of lactation (start of the experiment; 3.77 +/- 1.41 vs. 3.66 +/- 1.03 ng/ml) and 290th day of lactation (almost drying off; 4.75 +/- 3.05 vs. 4.44 +/- 0.96 ng/ml), cobalamin concentration in the milk colostrum showed a tendency towards a higher cobalt content in the ration of the supplemented cows in comparison with the controls (21.0 +/- 8.4 vs. 16.7 +/- 11.9 ng/ml). Differences in the vitamin B(12) concentration in the serum of the newborn calves before and after ingestion of colostrum were not detected. From these results it can be concluded that cobalt content of 0.13 mg Co/kg DM in the ration based on wilted grass silage seems to be sufficient for pregnant dairy cows. 相似文献
87.
88.
The feasibility of studying avian primordial germ cells in blood smears has been demonstrated. Blood smears prepared from chick embryos of stages 13 to 15 (48 to 55 hours) contained primordial germ cells, which were revealed by the periodic acidSchiff reaction. The presence of glycogen in the cytoplasm of the primordial germ cells facilitated their selective identification. 相似文献
89.
90.
Cyclic AMP-responsive DNA-binding protein: structure based on a cloned placental cDNA 总被引:117,自引:0,他引:117
J P Hoeffler T E Meyer Y Yun J L Jameson J F Habener 《Science (New York, N.Y.)》1988,242(4884):1430-1433