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JC Freeman 《Canadian Metallurgical Quarterly》1998,9(2):46-52
Medical nutrition therapy is essential for successful management in persons with diabetes. This article discusses implementation of the 1994 revised nutrition guidelines for persons with diabetes by the nonregistered dietitian professional, particularly in the nurse practitioner's setting. Major changes in the guidelines are addressed including the liberalization of sucrose, and basic nutrition assessment, referral guidelines, a sample nutrition history, and case studies to assist the nurse practitioner when a registered dietitian is unavailable. 相似文献
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Tlg1p and Tlg2p, members of the syntaxin family of SNAREs in yeast, have been implicated in both endocytosis and the retention of late Golgi markers. We have investigated the functions of these and the other endocytic syntaxins Pep12p and Vam3p. Remarkably, growth is possible in the absence of all four proteins. In the absence of the others, Pep12p and Tlg1p can each create endosomes accessible to the endocytic tracer dye FM4-64. However, although Pep12p is required for the ligand-induced internalization of the alpha factor receptor and its passage via Pep12p-containing membranes to the vacuole, Tlg1p is not. In contrast, Tlg1p is required for the efficient localization of the catalytic subunit of chitin synthase III (Chs3p) to the bud neck, a process that involves endocytosis and polarized delivery of Chs3p. In wild-type cells, internalized Chs3p cofractionates with Tlg1p and Tlg2p, and in a strain lacking the other endocytic syntaxins, either Tlg1p or Tlg2p is sufficient for correct localization of the enzyme. Pep12p is neither necessary nor sufficient for this process. We conclude that there are two endocytic routes in yeast that can operate independently and that Tlg1p is located at the junction of one of these with the polarized exocytic pathway. 相似文献
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C Buhler D Gadelle P Forterre JC Wang A Bergerat 《Canadian Metallurgical Quarterly》1998,26(22):5157-5162
DNA topoisomerase VI from the hyperthermophilic archaeon Sulfolobus shibatae is the prototype of a novel family of type II DNA topoisomerases that share little sequence similarity with other type II enzymes, including bacterial and eukaryal type II DNA topoisomerases and archaeal DNA gyrases. DNA topoisomerase VI relaxes both negatively and positively supercoiled DNA in the presence of ATP and has no DNA supercoiling activity. The native enzyme is a heterotetramer composed of two subunits, A and B, with apparent molecular masses of 47 and 60 kDa, respectively. Here wereport the overexpression in Escherichia coli and the purification of each subunit. The A subunit exhibits clusters of arginines encoded by rare codons in E.coli . The expression of this protein thus requires the co-expression of the minor E.coli arginyl tRNA which reads AGG and AGA codons. The A subunit expressed in E.coli was obtained from inclusion bodies after denaturation and renaturation. The B subunit was overexpressed in E.coli and purified in soluble form. When purified B subunit was added to the renatured A subunit, ATP-dependent relaxation and decatenation activities of the hyperthermophilic DNA topoisomerase were reconstituted. The reconstituted recombinant enzyme exhibits a specific activity similar to the enzyme purified from S.shibatae . It catalyzes transient double-strand cleavage of DNA and becomes covalently attached to the ends of the cleaved DNA. This cleavage is detected only in the presence of both subunits and in the presence of ATP or its non-hydrolyzable analog AMPPNP. 相似文献
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Well-differentiated thyroid cancer (i.e. papillary microcarcinoma) may be revealed by a clinically palpable cervical node, especially in young patients. Primary tumor specificity (small-sized, superior location, invasion, multifocality) and characteristics of cervical node involvement (with synchronous central and lateral multiple node spread) require appropriate treatment by a skilled surgeon. Contrary to the primary tumor treatment (total thyroidectomy), surgical management of the cervical node basins remains controversial. Only a special knowledge of the specificity of this disease and cervical lymphatic anatomy will ensure a good prognosis for the patient. 相似文献
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