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A 49-yr-old Japanese woman underwent upper gastrointestinal endoscopy because of nonspecific dyspepsia. Endoscopy revealed a flat elevated lesion about 15 mm in diameter adjacent to the duodenal papilla, the surface of which was uneven and covered with whitish granules. Based on the results of histological examination with immunohistochemistry (positive for CD10, CD20, CD79a, and bcl-2 protein, negative for CD5 and cyclin D1), a diagnosis of grade 1/3 follicular lymphoma was established. Systemic staging examinations suggested the lymphoma was restricted to the mucosa and superficial portion of the submucosa in the duodenal wall. The patient was treated with a combination of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisolone) and monoclonal anti-CD20 antibody (rituximab), in addition to radiotherapy. After six courses of this combination chemotherapy, complete regression of the lymphoma was observed. Although reports of small duodenal lymphoma (<20 mm or localized to the mucosa or submucosa) are extremely rare, the features of this case are characteristic of small duodenal lymphoma in terms of evolution around the ampulla of Vater, low-grade follicular type, occurrence in a women, occurrence in the fourth decade of life, and favorable outcome, and this type of tumor may need to be distinguished by pathogenesis and clinical behavior from various other gastrointestinal lymphomas.  相似文献   
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A new method was studied for eliminating HLA class I antigens from the surface of platelets without damaging the cells. Platelets were exposed to an acid solution (pH 3.0) to eliminate the antigenicity of HLA class I antigens. The reduction in antigenicities of HLA class I common antigen and individual HLA class I antigens by acid treatment was marked. Patients' sera which contained multispecific HLA antibodies reacted with PBS-treated platelets, but not with acid-treated platelets. No changes were observed in the antigenicities of glycoprotein Ib or glycoprotein IIb/IIIa. The viability of acid-treated platelets was 83%. Ultrastructural investigations revealed no significant difference between the PBS-treated platelets and acid-treated platelets. The platelet function studies showed that the aggregation of acid-treated platelets induced by various agonists was only slightly reduced compared with PBS-treated platelets. We propose that acid-treated platelets are promising for clinical use in patients refractory to platelet transfusions and may be superior to chloroquine-treated platelets for analysis of the specificity of antiplatelet antibodies.  相似文献   
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Ghrelin not only strongly stimulates GH secretion, but is also involved in energy homeostasis by stimulating food intake and promoting adiposity through a GH-independent mechanism. These effects of ghrelin may play an important role in the pathophysiology of inflammatory wasting syndrome, in which both the somatotropic axis and energy balance are altered. In this study we investigated plasma ghrelin concentrations after lipopolysaccharide (LPS) administration to rats, a model of the wasting syndrome and critical illness. In addition, the therapeutic potential of the antiwasting effects of ghrelin was explored using LPS-injected rats. A single LPS injection suppressed plasma ghrelin levels 6 and 12 h later. Maximal reduction was observed 12 h after LPS injection, in a dose-dependent manner. In contrast, plasma ghrelin levels were elevated after repeated LPS injections on d 2 and 5. Peripheral administration of ghrelin twice daily (10 nmol/rat) for 5 d increased body weight gain in repeated LPS-injected rats. Furthermore, both adipose tissue weight and plasma leptin concentrations were increased after ghrelin administration in these rats. In conclusion, plasma ghrelin levels are altered in LPS-injected rats, and ghrelin treatment may provide a new therapeutic approach to the wasting syndrome and critical illness.  相似文献   
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Effects of a single administration of captopril on plasma and urinary vasopressin (AVP) were examined in 8 normotensive (NT) female volunteers, 17 patients with essential hypertension (EHT) and 2 patients with primary aldosteronism (PA). Orally-administered captopril (25 mg) had no effect on plasma AVP levels in the three groups. However, urinary excretion of AVP decreased significantly after use of captopril in both NT and EHT subjects (-57% and -67%, respectively), and also in PA subjects. The magnitude of reduction in urinary AVP was significantly correlated with the pretreatment levels of plasma renin activity (r = 0.85) and plasma aldosterone concentration (r = 0.88) in NT subjects. Such correlation was not found in EHT subjects. These results suggest that captopril decreases AVP secretion in both normotensive and hypertensive subjects, but the relation of the magnitude in AVP reduction by captopril to the peripheral renin-angiotensin system might be different.  相似文献   
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BACKGROUND/AIMS: The anti-cancerous effect on hepatocellular carcinoma of a newly established form of thermotherapy, which uses an implant heating system, was evaluated. As a new material for application in hyperthermia, the authors developed a powder type Mg-ferrite complex that produces heat under a relatively low-power magnetic field. METHODOLOGY: This material suspended in Lipiodol was injected into tumors on the backs of mice that consisted of human hepatocellular carcinoma cells. Hyperthermia was performed by directing a magnetic charge on tumor-bearing mice that contained the Mg-ferrite complex. The temperature of the tumor was kept at 42-43 degrees C, while the magnetic field power ranged from 50 to 80G. RESULTS: A 10-min hyperthermia treatment was insufficiently effective against tumor growth. Systemic injection of doxorubicin (ADM) before hyperthermia appeared to enhance the anti-cancerous effect, but the difference was little and did not reach a statistically significant level (repeated measure analysis of variance). The anticancerous effect of hyperthermia for 15 minutes, in contrast, was marked. The nodules had almost completely disappeared by the end of the experiment. CONCLUSIONS: In conclusion, it is suggested that hyperthermotherapy using this newly developed Mg-ferrite complex might become an option for low-invasive therapy for advanced hepatocellular carcinoma in humans.  相似文献   
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