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971.
972.
Several studies have recently reported the development of colonic epithelial cell hyperproliferation in rodents following the ingestion of Western-style diets. In this study, additional measurements related to differentiation and maturation of the colonic epithelial cells were made after feeding this type of diet. Two Western-style diets high in fat and phosphate content and low in calcium and vitamin D were fed to C57BL/6J mice for 12, 24, and 52 weeks. Diet A contained American Blend fat as a source of lipids, diet B contained corn oil, and control diet C was a standard AIN-76A semisynthetic diet which is lower in fat content and higher in calcium and vitamin D. Colonic epithelial cells were studied for three biomarkers: cytokeratin catalogue no. 18 (clone LE64) expression, soybean agglutinin carbohydrate lectin binding, and acidic mucins including sialo- and sulfomucins. Feeding of diets A and B revealed that colonic epithelial cells had increased expression of cytokeratin catalogue 18 and SBA carbohydrate lectin binding compared to controls (P = 0.0001 for diet A versus C and diet B versus C). Significant differences were found between diets B and C (P = 0.0001) and diets A and C (P = 0.0001) in total acidic mucins and in the ratio of sialomucin:sulfomucin (P = 0.0001). These findings demonstrate that both functional and structural modifications occurred in colonic epithelial cells under these dietary conditions, and further defined this rodent model for preclinical evaluation of nutritional and chemopreventive interventions.  相似文献   
973.
Voltage-gated potassium (K(V)) channels play key roles in setting the resting potential and in the activation cascade of human peripheral T lymphocytes. Margatoxin (MgTX), a 39-amino acid peptide from Centruroides margaritatus, is a potent inhibitor of lymphocyte K(V) channels. The binding of monoiodotyrosinyl margatoxin ([125I]MgTX) to plasma membranes prepared from either Jurkat cells, a human leukemic T cell line, or CHO cells stably transfected with the Shaker-type voltage-gated K+ channel, K(V)1.3, has been used to investigate the properties of lymphocyte K(V) channels. These data were compared with [125I]MgTX binding to heterotetrameric K(V) channels in rat brain synaptic plasma membranes [Knaus, H. G., et al. (1995) Biochemistry 34, 13627-13634]. The affinity for [125I]MgTX is 100-200 fM in either Jurkat or CHO/K(V)1.3 membranes, and the receptor density is 20-120 fmol/mg in Jurkat membranes or 1000 fmol/mg in CHO/K(V)1.3 membranes. In contrast to rat brain, [125I]MgTX binding to Jurkat and CHO/K(V)1.3 membranes exhibits an absolute requirement for K+, with no potentiation of binding by Na+. K(V)1.3 was the only K(V)1 series channel present in either CHO/K(V)1.3 or Jurkat plasma membranes as determined by immunoprecipitation of [125I]MgTX binding or by Western blot analyses using sequence-specific antibodies prepared against members of the K(V)1 family. The relative potencies of a series of peptidyl K(V) channel inhibitors was essentially the same for inhibition of [125I]MgTX binding to Jurkat, CHO, or rat brain membranes and for blocking 86Rb+ efflux from the CHO/K(V)1.3 cells, except that alpha-dendrotoxin was more potent at blocking binding to rat brain membranes than in the other assays. The characteristics of [125I]MgTX binding, the antibody profiles, and the effects of the peptidyl K(V) inhibitors all indicate that the [125I]MgTX receptor in Jurkat lymphocytes is comprised of a homomultimer of K(V)1.3, unlike the heteromultimeric arrangement of the receptor in rat brain.  相似文献   
974.
BACKGROUND: Localized non-Hodgkin's lymphomas of the head and neck are generally treated with radiotherapy with or without chemotherapy, although the results of treatment of localized non-Hodgkin's lymphomas with of treatment of localized non-Hodgkin's lymphomas with chemotherapy alone appear to be favorable. It is unclear if and when combined modality therapy should be used. METHODS: The authors reviewed the records of 53 patients with Stage I or II non-Hodgkin's lymphoma of the head and neck, who were treated with radiotherapy alone (13 patients), chemotherapy according to the cyclophosphamide, doxorubicin, vincristine, prednisone- (CHOP) regimen (27 patients), or a combination of both treatments (13 patients). RESULTS: A complete remission was achieved in 43 (81%) patients. The 5-year survival for all patients was 78%. A significant difference (P = 0.03) in 5-year relapse-free survival was observed between Stages I and II disease, of 92 and 60%, respectively. Extensive tumor was a significantly poor prognostic factor (P = 0.04) with a 5-year relapse-free survival of 52 versus 84% for patients with nonextensive lymphoma. Eight relapses occurred; in five patients, a local relapse was the first presentation. Although salvage radiotherapy was successful in these five patients, a distant relapse developed in three. No relapses were observed in previously irradiated areas. CONCLUSIONS: Our results suggest that radiotherapy alone is the appropriate treatment for nonextensive Stage I intermediate grade non-Hodgkin's lymphoma of the head and neck. For extensive Stage I or II non-Hodgkin's lymphomas, chemotherapy is preferable. The value of combined modality therapy remains unclear.  相似文献   
975.
The authors compared the maximal duration of voluntary breath-holding in patients with panic disorder (N = 23), patients with generalized social phobia (N = 10), and healthy subjects (N = 26). Patients with panic disorder had significantly shorter breath-holding durations than either comparison group. Groups did not otherwise differ in physiologic response to the breath-holding. Implications for a false suffocation alarm in panic disorder are discussed.  相似文献   
976.
977.
Malignant chondroid syringoma, a very rare tumour, presenting with multiple pulmonary metastases in a 50 year old woman is described. Initial diagnostic confusion with pulmonary hamartoma occurred due to histopathological similarities. However, re-examination of a skin biopsy specimen taken 17 years previously from a hand lesion yielded the necessary information to identify the pulmonary lesions definitively as metastases from the original skin lesion. The features of this very rare indolent tumour are described.  相似文献   
978.
979.
Impaired esophageal body motility is a complication of chronic gastroesophageal reflux disease (GERD). In patients with this disease, a 360-degree fundoplication may result in severe postoperative dysphagia. Forty-six patients with GERD who had a weak lower esophageal sphincter pressure and a positive acid reflux score associated with impaired esophageal body peristalsis in the distal esophagus (amplitude <30 mm Hg and >10% simultaneous or interrupted waves) were selected to undergo laparoscopic Toupet fundoplication. They were compared with 16 similar patients with poor esophageal body function who underwent Nissen fundoplication. The patients who underwent Toupet fundoplication had less dysphagia than those who had the Nissen procedure (9% vs.44%; P=0.0041). Twenty-four-hour ambulatory pH monitoring and esophageal manometry were repeated in 31 Toupet patients 6 months after surgery. Percentage of time of esophageal exposure to pH <4.0, DeMeester reflux score, lower esophageal pressure, intra-abdominal length, vector volume, and distal esophageal amplitude all improved significantly after surgery. Ninety-one percent of patients were free of reflux symptoms. The laparoscopic Toupet fundoplication provides an effective antireflux barrier according to manometric, pH, and symptom criteria. It avoids potential postoperative dysphagia in patients with weak esophageal peristalsis and results in improved esophageal body function 6 months after surgery.  相似文献   
980.
The case of a 39-year-old female with mild renal failure and asymptomatic hyperuricemia who developed generalized exanthema, fever and eosinophilia followed by progressive jaundice and worsening of renal function 19 days after the initiation of treatment with alopurinol (300 mg/day) is reported. Liver biopsy showed a combination of mixed inflammatory infiltrate with abundant eosinophils and periportal necrosis and bridging, together with cholestasis and moderate steatosis. A review of the literature is made providing detailed analysis of other cases with preexisting renal failure and the role of renal dysfunction as a risk factor is discussed.  相似文献   
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