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91.
Daily variation in concentration of cortisol in plasma in intact and hypophysectomized gulf killifish 总被引:1,自引:0,他引:1
A daily variation in concentration of cortisol in plasma is synchronized by a 12-hour daily photoperiod in intact as well as in hypophysectomized fish. The daily rhythm in concentration of the adrenal steroid does not depend on a daily rhythm in the concentration of pituitary adrenocorticotropic hormone. 相似文献
92.
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
93.
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
94.
In landlocked countries, the role of fish is often poorly known and/or propagated. In many countries fish represent the biggest and qualitatively most valuable protein source (24% of the worldwide available animal protein) for human consumption. At present the economic significance of the production and trade of fish is already very high. However, according to FAO, the future demand of proteins can only be covered by a considerable expansion of the aquaculture production, in particular because of a stagnated fish catch and a continuous reduction of the agricultural production. The ideational value of ornamental fish appears obvious however pet fish keeping represents also a value worth of many millions US dollars worldwide. Finally the importance of fish will not only increase for economic, but certainly also for ecological reasons, because it is well established as an incorruptible bioindicator of our environment. 相似文献
95.
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
96.
97.
98.
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
99.
Trials were performed to investigate in which way mechanical and/or thermal treatment of horse beans would have an effect on the harmful components that were shown to be present in horse beans. In the course of these trials amino acids from heat-treated horse beans (variety Fribo) were analyzed for their true digestibility. Apart from heat-treated horse beans the investigation included undecorticated and decorticated beans and a mixture of horse beans with spring barley. 相似文献
100.