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Large numbers of wheat genotypes were grown under field conditions and screened for biotic stress tolerance and certain protective compounds. It was found that both the salicylic acid and polyamine contents of the investigated genotypes varied over a wide range, while the antioxidant enzyme activities showed a similar pattern in the different genotypes. In order to investigate stress-induced changes in salicylic acid and polyamine contents, samples were collected from plants artificially inoculated with leaf rust (Puccinia triticina), on which natural powdery mildew [Blumeria graminis(DC.) Speer f. sp. triticiEm. Marchal] infection also appeared. Biotic stress mostly resulted in elevated levels of total salicylic acid and polyamines in all the genotypes. The activities of various antioxidant enzymes showed similar changes after infection regardless of the genotype. The investigation was aimed at detecting a relationship between the level of stress tolerance and the contents of protective compounds, in particular salicylic acid and polyamines.

Low temperature stress results in significant yield losses in cereals. Cereals of subtropical origin like maize and rice are severely damaged at temperatures below 10°C and are killed at subzero temperatures. This stress effect is called chilling. In contrast, cereals originating from the temperate zone (wheat, barley, rye and oat) may survive short periods even between −10 and −20°C, depending on the species and varieties, so they are freezing-tolerant to various extents. For the winter type of these cereals a gradual decrease in temperature up to −4°C results in cold acclimation, which increases their freezing tolerance. In addition, it fulfils their vernalization requirement, which is necessary for the correct timing of the vegetative to generative transition. During both chilling and freezing, oxidative stress is induced. Although the accumulation of high concentrations of reactive oxygen species may be lethal, a moderate increase in their level may activate various defence mechanisms. In this review the role of reactive oxygen species, antioxidants, carbohydrates, free amino acids, polyamines and hormones in the response to low temperature stress in cereals will be described. The effect of light and the use of the model plant Brachypodium distachyonL. to reveal the biochemical and molecular biological background of this response will also be discussed.

The paper studies differences between functional specification methods. Communicational and behavioural models are defined and problems of using communicational models in automated design processes are exposed.

Summary Of 139 operations for gastric perforation performed in the 3rd Surgical Department of the University of Semmelweis, Budapest, between 1976 and 1985, 71 were for pyloric perforation. The postoperative mortality was 15.1 %. Perforated ulcers were treated with suture plication in 120 patients. This method resulted in a decrease in mortality by 3 %. The median time between the onset of symptoms and operation was 11.5 h. In 68.3 % of operative cases, the patient suffered from bacterial peritonitis. Simple closure seems to be the treatment of choice for perforations after 12 h. A definitive operation — vagotomy with or without excision and simple closure - should be considered within 12 h for good-risk patients with a long history of ulcer symptoms and no peritonitis.

Summary End-to-end anastomoses were formed with a microsurgical technique using 30-mm vicryl and nylon proximal to the duodenal papilla in the Göttingen minipig (n = 42). The monofilament sutures were mucosal, extramucosal and all layer. The authors found that the 8/0 vicryl monofilament mucosal suture made by the microsurgical technique provides the best results. They also found that mucosal regeneration was perfect and cholestasis in the liver was rare.