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A patient who developed a mixed neuroendocrine carcinoma and adenocarcinoma at the site of a previous long-standing ileostomy is reported. The neuroendocrine features are documented by both ultrastructural and immunocytochemical findings. Carcinoma arising in an ileostomy site is rare but has been recorded in patients with long-standing ileostomies after colectomy for chronic inflammatory bowel disease, as in this patient. Neuroendocrine carcinoma developing in this setting apparently has not been described before, however.  相似文献   
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A case report of a 10-year old girl with a herniated disc is presented. The most significant symptoms were progressive scoliosis with a flat back and paravertebral muscle spasm. An absent H reflex on the left and an increased latency of the somatosensory-evoked potentials of the left posterior tibial nerve were found. The computed tomographic scan of the lumbar spine showed a large central left-sided disc protrusion at the L5-S1 level. Our case presents the youngest patient with documented intervertebral disc herniation and the only one with severe scoliosis and vertebral rotation. The curve was not structural because it improved with surgery and an orthosis was not necessary.  相似文献   
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An early step in the development of vertebrae, ribs, muscle, and dermis is the differentiation of the somitic mesoderm into dermomyotome dorsally and sclerotome ventrally. To analyze this process, we have developed an in vitro assay for somitic mesoderm differentiation. We show that sclerotomal markers can be induced by a diffusible factor secreted by notochord and floor plate and that heterologous cells expressing Sonic hedgehog (shh/vhh-1) mimic this effect. In contrast, expression of dermomyotomal markers can be caused by a contact-dependent signal from surface ectoderm and a diffusible signal from dorsal neural tube. Our results extend previous studies by suggesting that dorsoventral patterning of somites involves the coordinate action of multiple dorsalizing and ventralizing signals and that a diffusible form of Shh/Vhh-1 mediates sclerotome induction.  相似文献   
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A protein-tyrosine-phosphatase (PTPase; EC 3.1.3.48) containing two Src homology 2 (SH2) domains, SHPTP1, was previously identified in hematopoietic and epithelial cells. By placing the coding sequence of the PTPase behind a bacteriophage T7 promoter, we have overexpressed both the full-length enzyme and a truncated PTPase domain in Escherichia coli. In each case, the soluble enzyme was expressed at levels of 3-4% of total soluble E. coli protein. The recombinant proteins had molecular weights of 63,000 and 45,000 for the full-length protein and the truncated PTPase domain, respectively, as determined by SDS/PAGE. The recombinant enzymes dephosphorylated p-nitrophenyl phosphate, phosphotyrosine, and phosphotyrosyl peptides but not phosphoserine, phosphothreonine, or phosphoseryl peptides. The enzymes showed a strong dependence on pH and ionic strength for their activity, with pH optima of 5.5 and 6.3 for the full-length enzyme and the catalytic domain, respectively, and an optimal NaCl concentration of 250-300 mM. The recombinant PTPases had high Km values for p-nitrophenyl phosphate and exhibited non-Michaelis-Menten kinetics for phosphotyrosyl peptides.  相似文献   
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In this report, the role of 34 kDa HA-binding protein in hyaluronic acid-induced cellular signalling in lymphocytes has been examined. The binding of 125I-HA to lymphocytes in vivo was found to be inhibited by pre-incubation of the cells with anti-34 kDa HA-binding protein antibodies, thus confirming 34 kDa HA-binding protein as the specific HA-receptor in lymphocytes. This observation was substantiated by anti-34 kDa HA-binding protein antibodies immunoblotting and 125I-HA ligand blotting of lymphocytes cell lysate. The HA-induced cell aggregation, tyrosine phosphorylation and cytoskeletal protein phosphorylation demonstrate the HA-induced early cellular signalling events in lymphocytes. Further, to study the involvement of 34 kDa HA-binding protein in mitogen induced lymphocyte signalling, we studied in vivo phosphorylation and secondary messenger formation. The enhanced 34 kDa HA-binding protein phosphorylation by HA and the inhibition of cellular aggregation and IP3 formation by anti-HA-binding protein antibodies revealed that 34 kDa HA-binding protein is one of the potential mediators in HA-induced signal transduction.  相似文献   
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The experience of our 16 patients treated for membranous duodenal stenosis is reported. Their treatment and course was analysed in a retrospective study. Eight patients were operated on within the first 16 days of life and in the remaining group surgery was performed at 1 month to 4 y of age. The presenting symptom leading to diagnosis was, in all but one case, non-bile-stained vomiting. Associated malformations were found in all but four patients, mostly morbus Down. The operative procedure performed was a partial excision of the duodenal membrane and a duodenoplasty in 10 patients, a duodenojejunostomy in 5 patients, and a duodenoplasty only in 1 patient. The postoperative course was without lethal complications. One late stricture in an anastomosis occurred. We conclude that in its presentation, duodenal stenosis differs from duodenal atresia, and can often be misinterpreted, resulting in a late diagnosis, and should be reported as a separate entity.  相似文献   
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With worldwide energy consumption rising, there is a need to reduce energy use of the housing stock. While this general idea is well-known, there is an overwhelming amount of product data and manufacturers claims through which the homebuilder or designer must sort to make informed selections of energy-efficient upgrades. The main objective of this research was to identify cost effective–energy efficient upgrades from a group of 16 commonly available choices, and rank them according to the most beneficial for the least cost. This study was conducted in Phoenix, Arizona, and included a sample of 30 production-style homes typical of the Phoenix metropolitan area. Energy-simulation software was used to perform energy evaluations and derive the benefits of each upgrade. The cost of each upgrade was obtained from a database of national average costs and from a local context. Differences in the selection of beneficial upgrades vary dramatically with the source of the cost information. This research provides a generic methodology that can be used by builders and designers to select appropriate energy-efficient upgrades for a given geographic area that will provide high operating benefits relative to the amount of capital investment.  相似文献   
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