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951.
This electron microscopical study was performed in order to follow the endocytic pathway of horseradish peroxidase and colloidal gold tracers and to determine the involvement of endocytosis in postnatal differentiation in superficial cells of the mouse urinary bladder epithelium. Morphometric analyses of late endosomes/multivesicular bodies from day of birth to day 25 were performed. The internalisation and intracellular transport of luminal plasmalemma to multivesicular bodies via endocytic vesicles, early endosomes and pleomorphic compartments was established. Dynamic changes in endocytic activity took place within the first few days of postnatal differentiation. During this period the number of multivesicular bodies changed in an inverse ratio to their size. After the third day endocytic activity gradually approached the low rate of adult urothelium.  相似文献   
952.
Affiliate of the L. Ya. Karpov Scientific-Research Institute of Physical Chemistry. Translated from Atomnaya énergiya, Vol. 76, No. 5, pp. 422–428, May, 1994.  相似文献   
953.
Antigen-induced arthritis in guinea pigs was used as a model to investigate the pathogenic mechanisms responsible for cartilage destruction in chronic joint inflammation. The activation of macrophages, their effects on cartilage metabolism, and the development of autoimmunity to cartilage constituents were studied during the progression of arthritis. The results show that in arthritic animals the macrophages are systemically activated, with a peak in the early phase of inflammation. Interleukin 1, produced by the activated cells, suppresses the proteoglycan synthesis in cartilage explants and cultured chondrocytes and increases the proliferation of the cells in vitro. During the progression of arthritis humoral and cell-mediated immune responses to collagen type II and cartilage proteoglycans occur correlating with the severity of arthritis. It is concluded that different immunological mechanisms may be involved in cartilage destruction during antigen-induced arthritis. Mediator-induced metabolic reactions dominate in the early phase, whereas autoimmunity to cartilage might play an essential role in later phases of arthritis.  相似文献   
954.
This paper describes an approach, conceptual framework, and software architecture for dynamic reconfiguration of the order picking system. The research and development project was sponsored by the Material Handling Research Center (MHRC), a National Science Foundation sponsored Cooperative Industry/University Research Center. The storage configuration is assumed to be an in-the-aisle order picking system in which stockkeeping units (SKUs) can occupy variable capacity storage locations and stock-splitting is allowed among zones (clusters). The product mix may include multiple product families with different life cycles, correlated demand within families and commonality of demand across families.  相似文献   
955.
OBJECTIVE: To determine the characteristics and long-term outcome of radiation-induced thyroid cancer in children. DESIGN: Retrospective review of a cohort of 4296 irradiated patients who received childhood radiation treatment to the head and neck area at the same hospital. PATIENTS: Forty-one children who were younger than 20 years when thyroid cancer developed in them and 77 adults in whom thyroid cancer developed. All 118 cases were diagnosed before 1974 and were followed up for a median of 19.4 years. RESULTS: Children presented with clinically palpable lymph nodes more often than adults (30.7% vs 15.1%, P = .05) and had more recurrences (39% vs 16%, P = .05). Despite these frequent recurrences, only one patient (an adult) died of thyroid cancer. Seventy percent of the recurrences occurred during the first 10 years of follow-up, but recurrences continued after 20 years. The adults had previously identified factors that predicted the risk of recurrences, but none could be identified in the children. CONCLUSION: The presentation and relatively good outcome of radiation-induced thyroid cancer in children is similar to that in nonirradiated children. Frequent and late recurrences call for lifelong follow-up.  相似文献   
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In a prospective study of 79 patients with arthrographically verified acute ruptured lateral ankle ligaments we have evaluated the long-term results of three different treatments: operation and walking-cast, walking-cast alone and elastic bandage. The average follow-up period was 11 (9-13) years, and 32 parameters concerning interview, clinical and radiographic examinations were statistically analysed. The three kinds of treatment were found to be equal, since only one parameter showed significant difference at a 5% level using Fisher's exact and the Mann-Whitney test, and no difference by using the Kruskal-Wallis test for homogeneity. Residual disabilities and late complications, such as instability, pain on activity, and the number of secondary ligament reconstructions and talocrural arthroses were low. It was concluded that nonoperative treatment provided adequate results even after a decade.  相似文献   
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