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Polymeric compounds of the cell walls of Act. rimosus were studied during the actinomycete growth. It was found that the content of teichoic acid decreased 2 times by the end of development of Act. rimosus, while content of glycane polymer remained approximately at the same level. The molar ratios of teichoic acid and glycopeptide glycane were determined.  相似文献   
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Article covers approaches to evaluation and forecasting of occupational risk for workers exposed to occupational hazards, formulates a concept to evaluate occupational disease according to risk and severity categories, gives an integral parameter for qualitative and quantitative analysis of group risk for one occupational disease or their combination. Trials proved acceptability of the method for group risk evaluation according to WHO concept concerning occupational diseases.  相似文献   
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A computerized database containing DNA sequence information regarding human HPRT mutants has been created. The database itself is in the dBASE format and contains information on about 1500 mutants. In addition, an IBM PC compatible software package to analyze the information in the database has been developed. Both the database and software are freely available via the Internet.  相似文献   
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One hundred and seventy cancerous lesions observed among 159 esophagectomised specimens were systematically investigated with histochemical staining methods in addition to the ordinary hematoxylin-eosin staining. About 2/3 of them, 113 lesions, were entirely consisted of the squamous elements, regardless with pearl-formation or not, Group 1. On the contrary, the remaining 57 lesions (33.5%) showed foci of esophageal gland-like transformation, Group 2. Those lesions were specified by constituent epithelia with esophageal glandular epithelia-like characteristics; positive for epithelial mucin, secretory component and S-100 protein. Such esophageal gland-like structures could be demonstrated exclusively in cancerous foci penetrated through the lamina muscularis mucosa. Those 113 lesions of the Group 1 did not show any such transformation even by the meticulous examination of the whole lesion by the step sectioning. Those lesions of the Group 2 had a distinct tendency of the perpendicular mural penetration and submucosal extension than the horizontal mucosal involvement, giving rise a characteristic appearance resembling to submucosal tumors. On the contrary, those of the Group 1 showed an ordinary mural extension pattern corresponding to the extent of mucosal involvement, so-to-speak, a typical features of common esophageal cancer. No outstanding difference in biological behaviours could be obviated between two groups so far examined; survival rate, lymph node metastasis, vascular permeation, intraepithelial extension, etc.  相似文献   
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