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51.
Blom T Franzén A Heinegård D Holmdahl R 《Science (New York, N.Y.)》2003,299(5614):1845; author reply 1845
52.
53.
Gertrud Franz 《植物养料与土壤学杂志》1975,138(1):73-87
Temperature demands of microscopic soil fungi from different climatic and geographical sites. . 154 strains of microscopic soil fungi were isolated at 25°C from soils deriving from tropical to alpine climatic zones of the world (SW-Africa, Argentine, Nepal, Canary Islands and W-Germany). Determining their saccharolytic, amylolytic and proteolytic activities on saccharose-, starch- or gelatine-containing agar plates at 5 °C, 15 °C, 25 °C, 35 °C and 43 °C, the activity range as well as the optimal temperature were obtained. The following results were obtained: 1) A clear correlation between the temperature requirements of the fungal flora and the climatic conditions of the site of isolation was observed. 2) The fungal flora of a certain climatic zone was composed of strains of ubiquitously distributed species. Their great adaptability enables them to accomodate themselves to the temperature conditions of each site. 3) A smaller percentage of species was characterised by a small range of temperature variability and therefore depending on a certain climatic zone. Some of these were strict pschychrophilic species, characteristic for alpine and subalpine regions, but others behaved as strict mesophiles observed only in warm regions. 4) Finally from each site of isolation there also could be isolated a certain amount of fungi, whose ecological demands did not or only for a very short time coincide with the bioclimatic conditions of the particular site. Generally, these isolates are able to form resistant spores enabling them to survive unfavourable climatic conditions. . 相似文献
54.
Oxygen profiles and methane turnover in a flooded rice microcosm 总被引:19,自引:0,他引:19
Summary Dissolved O2 was depleted within the top 3.5-mm surface layer of flooded rice soil microcosms without plants. In planted microcosms, however, O2 was detectable down to at least 40 mm in depth. O2 concentrations in the uppermost soil layers of microcosms with rice plants were higher in the light than in the dark, indicating O2 production by photosynthesis. The CH4 emission rates were nearly identical for illuminated and for darkened microcosms, demonstrating that the photosynthetically produced O2 did not increase CH4 oxidation in the rhizosphere. In contrast, CH4 emission rates increased when the microcosms were incubated under an N2 atmosphere, indicating that transport of O2 from the atmosphere into the rhizosphere was important for CH4 oxidation. CH4 emission under air accounted for only 10%–20% of the cumulative CH4 production determined in cores taken from the microcosms. Apparently, 80%–90% of the CH4 produced was oxidized in the rhizosphere and thus was not emitted. 相似文献
55.
Krist S Stuebiger G Unterweger H Bandion F Buchbauer G 《Journal of agricultural and food chemistry》2005,53(21):8310-8316
Poppy seed oil (Oleum Papaveris Seminis) is used for culinary and pharmaceutical purposes, as well as for making soaps, paints, and varnishes. Astonishingly, hardly anything was yet known about the volatile compounds of this promising comestible. Likewise, there are no current published data about the triglyceride (TAG) composition of poppy seed oils available. In this investigation solid-phase microextraction (SPME) with DVB/Carboxen/PDMS Stable-Flex fiber was applied to the study of volatile compounds of several seed oil samples from Papaver somniferum L. (Papaveraceae). 1-Pentanol (3.3-4.9%), 1-hexanal (10.9-30.9%), 1-hexanol (5.3-33.7%), 2-pentylfuran (7.2-10.0%), and caproic acid (2.9-11.5%) could be identified as the main volatile compounds in all examined poppy seed oil samples. Furthermore, the TAG composition of these oils was analyzed by MALDI-ReTOF- and ESI-IT-MS/MS. The predominant TAG components were found to be composed of linoleic, oleic, and palmitic acid, comprising approximately 70% of the oils. TAG patterns of the different poppy varieties were found to be very homogeneous, showing also no significant differences in terms of the applied pressing method of the plant seeds. 相似文献
56.
Sutor A Schwarz S Conraths FJ 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(11-12):457-464
Some invasive wildlife species have the potential to act as additional host and vector species for parasitic and other infectious diseases. We used the raccoon dog (Nyctereutes procyonides), a carnivore species that has its origin in Asia, as an example to demonstrate biological and ecological prerequisites which enables an invasive species to occupy a new habitat permanently. Studies conducted during the last ten years identified a total of 23 endoparasites, two ectoparasites, six bacterial or protozoan species and five viruses, found in the Nyctereutes procyonoides ussuriensis subspecies in its newly occupied range or in N. procyonoides koreensis in its original range. Results of studies in Finland and Germany furthermore showed that biological characteristics of the raccoon dog make this carnivore an appropriate host or vector for a variety of parasites and infectious diseases. This may result in a growing importance of this invasive carnivore for the epidemiology of transmissible diseases in Germany. Especially with regard to zoonotic disease outbreaks, the raccoon dog should therefore be paid more attention in disease prevention and eradication strategies. 相似文献
57.
58.
S Franz M Hofmann-Parisot M Gumpenberger 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(5-6):202-209
Beside the clinical examination of udder/teat imaging methods e.g. sonography, radiography and endoscopy allow diagnosis. This publication will give a summary of currently used and potentially usable methods of diagnostic imaging applied to the teat. Advantages and disadvantages of the several methods were compared--as quoted in literature and completed by own experiences. 相似文献
59.
J.M. Franz 《EPPO Bulletin》1973,3(3):85-87
Knowledge of pest population dynamics is required to assess the future abundance of a pest, the losses to be expected and the economic threshold. Mortality of pests caused by diseases can greatly influence their development and a valuable assessment can therefore only be based on healthy individuals. Examples of monitoring the health status are usually taken from the forest and from such insects that develop slowly and allow an assessment of the epizootic before the damaging final instar has been reached (caterpillars, sawflies). In agriculture, the tendency of reducing crop rotation increases the permanence of regulative forces and is consequently favourable. This allows for a more precise prediction on the development of epizootics. Recent observations show that appropriate sampling of aphid populations designed to determine their health status in respect to fungal epizootics can greatly increase the accuracy of the forecast on future trends in population dynamics. 相似文献
60.
Z E Kowalski R C Franz W J Coetzee W H Giesecke 《The Onderstepoort journal of veterinary research》1984,51(3):209-212
Using the composite fibrin plates method, plasminogen activator (PA) activity was found in secretions from clinically normal, mastitic, lactating and dried-off udders of dairy cows. The possible involvement of the fibrinolytic system in the physiology and pathology of the bovine mammary gland is discussed. 相似文献