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Ultrastructural changes were found to occur in the mycelium of Actinomyces hygroscopicus, strain 33x, which produced an exocellular proteolytic enzyme during submerged fermentation, in both laboratory and semiindustrial conditions (in 100-1 fermenters). In the course of the enzyme accumulation, numerous vacuoles appeared in the hyphae, some hyphae became wider, and the cell walls were more loose. The greatest structural changes were found in the intracytoplasmic membrane systems. The ultrastructural changes of the mycelium are not presumably connected with the accumulation of the enzyme, but are the result of the differentiation of cellular structures during aging of the cells and their transition to the stage of autolysis.  相似文献   
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A review of 1,000 consecutive coronary angiograms, most of them performed for evaluation of angina pectoris, yielded 9 examples of congenital anomalies of the coronary arteries. In 2 cases the angina may have been due to malposition of the left coronary artery or one of its branches. There were 2 cases of aberrant origin of the circumflex artery from the right coronary artery, 2 cases of aberrant left anterior descending artery, 3 cases in which all three major coronary branches arose from the right aortic sinus, and 2 cases of coronary artery fistulas. Malposition of the coronary artery should be considered as a possible cause of angina.  相似文献   
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Crimean-Congo haemorrhagic fever (C-CHF) re-emerged recently in the United Arab Emirates. The clinical outcome of 11 cases of viral haemorrhagic fever patients admitted to hospital between June 1994 and January 1995 is described. Four cases were laboratory confirmed retrospectively as C-CHF, the other patients were diagnosed likely to have the same disease on epidemiological and clinical grounds. In 72.7% of the patients, infection was fatal. Symptoms started 3.5 days before hospitalization. On admission, 81.8% of patients had high fever, 45.5% were vomiting, 63.6% had diarrhoea, 45.5% had haemorrhagic signs, and 18.2% had throat pain. Fatalities occurred 6.8 days after admission. Survivors were hospitalized for 9.3 days. Nosocomial transmission was not observed.  相似文献   
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