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The object of this study was to determine the effect of calcium carbonate or calcium phosphate supplements on dietary protein and fat utilization from low and high manganese diets. During the 63-day study, the 14 human adult subjects ate a constant laboratory controlled diet. In separate periods, subjects consumed the basal diet alone or with supplements of calcium carbonate, calcium carbonate plus manganese gluconate, calcium phosphate, or calcium phosphate plus manganese gluconate. Contrast analyses of data indicated that manganese gluconate supplementation of diets, when combined with either calcium phosphate or calcium carbonate, increased fecal losses of fat. When used as single supplements, both calcium phosphate and calcium carbonate depressed fecal fat loss in comparison with values when no supplements were used. Manganese gluconate supplements depressed fecal nitrogen losses calculated as a percentage of dry fecal weight.  相似文献   
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Interleukin-31 (IL-31), an IL-6 cytokine family member, is proposed to play a role in animal models of airway hyperreactivity. It is produced by activated T cells and signals via a heterodimeric receptor complex composed of IL-31Ralpha and OSMRbeta. Only low levels of IL-31Ralpha expression have been demonstrated in pulmonary epithelial cell lines, however, and little is known about the ability to regulate its expression and signaling. Therefore, primary cultures of human bronchial and alveolar epithelial cells, pulmonary fibroblasts, pulmonary macrophages, and established lines of immortalized bronchial epithelial cells (HBE) and alveolar carcinoma cells (A549) were analyzed by RT-PCR, immunoblotting, and thymidine incorporation. Distinct, cell type-specific regulation of IL-31Ralpha expression was detected. Transforming growth factor-beta (TGF-beta) enhanced IL-31Ralpha mRNA expression in primary cultures and established lines of epithelial cells, but not in macrophages. In contrast, interferon-gamma (IFN-gamma) induced IL-31Ralpha mRNA expression in macrophages. IL-31Ralpha protein expression was below detection threshold in primary epithelial cell cultures but was detectable in A549 cells and increased with TGF-beta treatment. In HBE and A549 cells, TGF-beta pretreatment increased IL-31-mediated Stat3 and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. In A549 cells, TGF-beta magnified IL-31-dependent suppression of proliferation. The data suggest that increased IL-31Ralpha expression correlates with an enhanced response to IL-31.  相似文献   
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Guinea pigs received a suboptimal transfer of lymphocytes sensitized to myelin basic protein (BP) and were then immunized with guinea pig BP, BP plus chicken brain or chicken myelin, or chicken brain alone. Sera from these animals were tested for the presence of myelinotoxic antibodies, as detected by the myelination inhibition assay. Myelination inhibition activity correlated with the histologic severity of demyelination.  相似文献   
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The Illinois Cancer Center entered 25 patients on a phase II trial of intravenous melphalan treating patients with recurrent, metastatic or locally advanced and inoperable squamous cell carcinoma of the head and neck. All patients had bi-dimensionally measurable disease, at least a sixty day life expectancy, and adequate performance status (ECOG scale 2). All patients except one had received prior radiotherapy, chemotherapy or both. Melphalan dosage was 30 mg/m2 every three weeks. Twenty-four patients were evaluable for response. One patient with laryngeal carcinoma had a clinical complete response of a nodal metastasis. Four patients had stabilization of disease for one to three months. There was formidable toxicity, including neutropenia (ANC < 1000/l 36%), and thrombocytopenia (< 50,000/l 32%). There were no drug-related deaths. Melphalan administered intravenously does not appear to be efficacious therapy in patients with previously treated advanced head and neck squamous carcinomas.  相似文献   
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The Ardennes and Eifel region is a geologically distinct area covering parts of Germany, Belgium, France, and Luxembourg where enhanced concentrations of radon occur in some houses and other buildings. An international case-control study is being conducted to examine the role of radon in the etiology of lung cancer in this area. The radon detectors used are issued by different laboratories involving a variety of detector types and processes. A series of intercomparisons in houses was therefore conducted under similar conditions of exposure in the field. In most situations the different detectors gave similar results. Nevertheless, in some situations open and closed detectors yielded different results. Therefore, estimates of radon exposure have to be adjusted if results are to be pooled.  相似文献   
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Cameron BM  Allen RC  Merril C 《Spine》2000,25(15):1917-1924
STUDY DESIGN: One-dimensional polyacrylamide gel electrophoresis was used to study serum esterase enzymatic activity in three groups of patients and one group of normal volunteers. OBJECTIVES: To determine whether there is a statistically significant correlation between variations of serum pseudocholinesterase and the perception of pain in patients with chronic spinal pain. SUMMARY OF BACKGROUND DATA: Changes in levels of cholinesterase in the extracellular space of the brain and in the cerebral spinal fluid have been found to be associated in animal pain experimentation. METHODS: Ninety-three surgical patients with chronic spinal pain, six surgical control subjects operated for conditions not associated with pain, 21 normal control volunteers, and nine disabled patients receiving monetary benefits were studied. The patients were analyzed for a period of time by rating the perception of their pain with a visual assessment score at the time venous blood was drawn. Serum samples were prepared, serum pseudocholinesterase was monitored, separated, and quantified according to Allen et al.5 Paired sample t tests were used to statistically evaluate the data. RESULTS: A trend of correlation was noted between preoperative serum pseudocholinesterase levels and visual assessment score: serum pseudocholinesterase levels increased as visual assessment score increased. The mean preoperative serum pseudocholinesterase level of chronic spinal pain patients (1313; SE = 26), which was significantly higher than the mean levels of the normal control volunteers (941; SE = 24; P<0.001) and that of surgical control subjects (1018; SE = 63; P <0.01), decreased significantly with anesthesia (P<0.005). The mean preoperative serum pseudocholinesterase level of the surgical controls, however, remained unchanged with anesthesia. A correlation demonstrated between visual assessment score and serum pseudocholinesterase in chronic spinal pain patients was not observed in six of nine patients receiving disability payments for more than a year. CONCLUSIONS: Measurements of quantitative alterations of serum pseudocholinesterase levels may be useful in the treatment of patients with chronic spinal pain.  相似文献   
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PURPOSE: The purpose of this retrospective analysis was to evaluate the emergence of second primary malignancies and the contribution of different causes of death to the outcome of patients with locoregionally advanced head and cancer receiving primary chemoradiotherapy. EXPERIMENTAL DESIGN: We studied 324 patients with stage IV squamous cell head and neck cancer who were enrolled on five consecutive multicenter Phase II studies of concurrent chemoradiotherapy. All of the regimens included concurrent 5-fluorouracil and hydroxyurea on an alternate week schedule with radiotherapy, either alone (FHX) or with cisplatin (C-FHX) or paclitaxel (T-FHX). The cumulative incidence of second primary tumors or death from any cause was estimated using methods of competing risk analysis. RESULTS: Median follow-up of surviving patients was 5.2 years (2-10.6 years). The 5-year overall survival and progression-free survival of the cohort were 46% and 65%, respectively. Causes of death and median time of occurrence were as follows: disease (n = 88; 1.5 years), treatment-associated acute or late complications (n = 30; 4 months), second primary tumors (n = 18; 3.5 years), comorbidities (n = 41; 1.9 years), and unknown (n = 20; 5.1 years). Predominant causes of death from comorbidities were cardiac and respiratory illnesses. Twenty-six patients (8%) developed a second primary tumor at a median time of 2.8 years (4 months to 10 years). The cumulative incidence of second primary tumors was 5%, 7%, and 13% at 3, 5, and 10 years, respectively. The most frequent site of second primaries was the lung (n = 13), followed by the esophagus (n = 3) and head and neck (n = 2) CONCLUSIONS: Patients with locoregionally advanced head and neck cancer treated with concurrent chemoradiotherapy are potentially curable but face significant risks of mortality from causes other than disease progression. Ameliorating toxicity, and implementing secondary screening and chemoprevention strategies are major goals in the management of head and neck cancer.  相似文献   
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