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Three forms related to different age groups are discussed. Special attention is devoted to laboratory analyses in support of clinical diagnosis. A representative sample of sera from the healthy population of Thuringia showed 6.97 per cent positive sera. The difference between the exposed agricultural and forestry workers and industrial workers is significant. Moreover, there is a relationship between the extent of wooded country and the presence of microfoci.  相似文献   
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Some laboratory studies have suggested that whereas food restriction in animals leads to response alternation (behavioural flexibility), water restriction induces perseverative, stereotyped responding. Hooded rats, restricted to 1 hour per day access to either food or water, were tested on a radial-arm maze (using a procedure that eliminates algorithmic response strategies), for alternation in a 3-arm maze (both when the maze was familar and unfamilar, and with or without differential reward) and a 2-choice maze in which some animals were taught to alternate direction of turn, and others to perseverate. Both groups performed the radial-arm maze task competently and spontaneously alternated at a high rate. In the learned task, food-restricted rats were slower than water-restricted to reverse a consistent direction of turn; in the alternation condition, water-restricted rats developed a temporary, but strong, directional bias when making their first choice each day. Water-restricted subjects took water more readily than food-restricted took food when initially introduced to the apparatuses, but there was no consistent difference in motivation in the two conditions. The results provide little support for the notion that distinct cognitive-motivational states or behavioural strategies are induced by food- and water-restriction.  相似文献   
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A large number of experiments in successive tests of episodic memory have focused on an experimental paradigm called recognition failure of recallable words. In this paradigm, a cued recall test follows a recognition test. Large amounts of data have revealed a lawful moderate dependence between recognition and cued recall. TECO (Sikstr?m, 1996b), a general connectionist theory of memory, has been applied for the phenomenon of recognition failure. This paper makes a strong claim that all possible pairwise combinations of successive tests between recognition, cued recognition, cued recall, and free recall follow a lawful relationship. The quantitative degree of the dependency predicted between these tests can be summarized in one function. Four experiments were conducted to test this claim. In line with the predictions, the results show that all pairwise combinations of these tests fit reasonably well with the proposed function. The TECO theory suggests theoretical insights into how recognition and recall may be divided into a recollection component, a familiarity component, and a cue-target integration component.  相似文献   
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