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1.
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
2.
B Rehberg R Rüschner M Fischer BJ Ebeling A Hoeft 《Canadian Metallurgical Quarterly》1998,33(7):425-429
Despite improvement in early diagnosis, surgical techniques, and general patient care, most deaths of cancer patients result from metastases. Recent studies have revealed that cytokines produced by cancer cells or by stromal cells play an important role into development the cancer metastasis. The formation of a cancer metastasis involves several major steps: 1) extensive vascularization; 2) local invasion; 3) adherence either to capillary endothelial cells or to subendothelial basement membrane; 4) extravasation; and 5) proliferation. In colon cancer, several cytokines such as growth factors, inflammatory cytokines, and angiogenic factors have been confirmed to be involved in each step of metastasis. This paper summarizes the involvement of cytokines in the development of invasion and metastasis in colon cancer. 相似文献
3.
Perthes' disease treated by prolonged recumbency and femoral head containment: a long-term appraisal
The results of a long-term review of 102 hips in eighty-seven patients with Perthes' disease are described, the mean follow-up interval being seventeen years. All had been treated by an extremely rigorous conservative regime in which the patients were kept in hospital for an average period of twenty-six months, during which time they were confined to bed with the legs in wide abduction, first in traction and later in "broomstick" plasters to ensure "containment" of the femoral head. The patients were assessed by the joint clincial and radiological method described by Ratliff (1956). The results were very satisfactory, with only 2 per cent poor results and 10 per cent fair. The remaining 88 per cent were good. The radiological results at the end of treatment have also been compared with control series described by Catterall (1972) and with the osteotomy series of Lloyd-Roberts, Catterall and Salamon (1976). From this it appears that the described regime offers no benefit compared with the natural history in Catterall's Groups I and II, and in Group III the results were only marginally better than those following osteotomy. In Group IV cases, however, where the femoral head was totally involved, the benefit was important, and since these are the cases which carry the worst natural prognosis it is suggested that the use of the method described in such instances must be seriously considered in spite of its social disadvantages. The theoretical implications of the findings are considered, and it is concluded that the benefits of the method cannot be ascribed wholly to the application of the "containment" principle. 相似文献
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The effect of cetylpyridinium chloride (CPC) on pathogenic fungi and Nocardia asteroides was studied. Sputa seeded with each of 11 organisms (Aspergillus flavus; Aspergillus fumigatus, Blastomyces dermatitidis, Candida albicans, Coccidioides immitis, Cryptococcus neoformans, Geotrichum candidum, Histoplasma capsulatum; Nocardia asteroides, Paracoccidioides brasiliensis, and Sporothrix schenckii) were treated with CPC and kept for 2, 5 and 9 days. The CPC reagent used (0.5% CPC and 0.5% sodium chloride) is one the Mycobacteriolgoy Branch at the Center for Disease Control added to sputa before shipping them to laboratories for recovery of mycobacteria. None of the organisms tested survived this treatment, and none was recovered on mycological or mycobacteriological media. Seeded sputa containing these organisms were also tested with a second CPC reagent (0.02% CPC and 0.5% sodium chloride) and held for 2, 5 and 9 days. A few colonies of A. flavus, A. fumigatus, and N. asteroides were recovered from these samples. Neither the morphology of the fungi nor their stainability by the fluorescent antibody method was affected by treatment with the reagent containing 0.5% CPC. However, the background material in smears from the 0.5% CPC-treated samples retained the conjugate, and this made weakly fluorescing organisms more difficult to detect. The 0.5% CPC treatment did not alter the morphology of N. asteroides or its ability to be stained with Kinyoun acid-fast stain. 相似文献
6.
Somatic, psychomotor, and intellectual development were studied in 11 patients who had total correction of congenital cardiac malformation in early infancy by the method of surface-induced deep hypothermia and circulatory arrest up to 43 minutes. Time between operation and re-evaluation ranged from 3 to 11 years (average 7 years). Somatic development was normal in all children. Psychomotor and intellectual behavior, measured by a battery of specially adapted test methods, failed to show a statistically significant difference when compared between the study group, a matched control group, and the normal population. Normal scores in psychomotor tests and normal intelligence quotients (I.Q.) were present in 8 patients; mental retardation was found in 2 patients: and unstable behavior, evident from different tests, was present in one. Except for the last case, in none of the patients was the method was found to be the primary cause of the abnormal behavior. Deep hypothermia and circulatory arrest in early infancy does not appear to have a negative influence on somatic, psychomotor, or intellectual development. 相似文献
7.
After presenting the topographical and pathological basis for the habitual luxation of the shoulder joint, our experience with the Bankart-Müller operation on 38 of our own patients was described. The results are characterized as very good, particularly two years and longer after the operation. 相似文献
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The localization of soluble, cercarial antigen preparation (CAP) in cercariae and schistosomules of Schistosoma mansoni was performed at the light and electron microscope levels using the unlabeled antibody method. Reaction produce was observed associated with the contents of the pre- and postacetabular glands and with the filamentous coat of mature cercariae. No reaction product was observed associated with the glycoacalyx of schistosomules. However, several schistosomules did retain remnants of their filamentous coats and reaction product was observed associated with those remains. CAP components were also observed in the area surrounding the intrasporocyst cercariae. 相似文献