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Four human monoclonal rheumatoid factors (MRF) were used to raise a panel of mouse monoclonal antibodies (mAb) which were selected in a solid-phase radioimmunoassay for binding to MRF but not normal IgM. Three mAb, each raised against a different MRF, bound to the majority of MRF and also to most polyclonal RF. Four other mAb bound selectively to the MRF against which they were raised and to no other MRF, and rarely to any polyclonal RF. Competition studies using cold and radiolabeled mAb further indicated that these mAb recognize distinct and different epitopes on MRF. RF activity of MRF was inhibited by 3 of the 4 mAb binding to a single MRF and 2 of the 3 mAb binding to multiple RF. It was thus concluded that of this panel of mAb 3 recognized cross-reactive idiotopes and the remainder demonstrated highly restricted idiotopes on MRF. These mAb identified MRF idiotopebearing cells in the peripheral blood of 3 of the MRF donors (and a further subject with type II essential cryoglobulinemia), with a frequency ranging from 0.3–10% of all mononuclear cells with the mAb to restricted idiotopes or 1.5–17% with mAb to cross-reactive idiotopes. These anti-idiotopic mAb should thus provide a highly specific means of identifying and monitoring MRF-producing cells in vivo.  相似文献   
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We have previously shown that interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha mRNA levels in rat alveolar macrophages are increased in by endotoxin (lipopolysaccharide; LPS)- stimulation and further enhanced by culturing with low-Mg2+ medium. We have now investigated the mechanisms of underlying this enhancement by using some specific signal transduction inhibitors. The enhanced elevation of both mRNAs levels was suppressed by pretreatment with TMB-8 (which inhibits calcium release from the endoplasmic reticulum) or dexamethasone (which inhibits nuclear factor [NF]-kappaB and activator protein [AP]-1), but not with verapamil or nifedipine (which inhibits calcium channels). The enhancment of IL-1beta, but not TNF-alpha mRNA levels, was suppressed by pretreatment with W-7 (which inhibits calmodulin), whereas the enhancement of TNF-alpha mRNA levels was suppressed by pretreatment with U73122 (which inhibits phospholipase C). Curcumin (an inhibitor of AP-1), suppressed the increases in both mRNAs induced by low-Mg2+ medium alone, but had no suppressive effect on the levels of either mRNA after LPS-stimulation in low-Mg2+ medium. Pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB) prevented the elevation of TNF-alpha mRNA levels induced by low-Mg2+ medium without LPS-stimulation, but had no suppressive effect on IL-1beta mRNA levels. From these results, we conclude that the enhanced elevation of IL-1beta and TNF-alpha mRNA levels seen in LPS-stimulated alveolar macrophages in low-Mg2+ medium occurs partly via the same, and partly via different, signaling pathways.  相似文献   
35.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
36.
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective.  相似文献   
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A boy with skin eruptions resembling varicella and specific for Langerhans cell histiocytosis (LCH) is reported. At his initial visit when he was four months old, vesiculopustular lesions were present over the entire body; these had first appeared on the third day post partus. Histopathological, immunohistochemical, and electron microscopical examination confirmed the Langerhans cell phenotype and Birbeck granules in the responsible cells. He also had hydronephrosis, recurrent fever, and cutaneous bacterial infections. His parents refused further medical treatment and he died of diarrhea with cachexia about two years later. LCH may present diagnostic difficulties by manifesting as a skin eruption which resembles varicella.  相似文献   
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Prostatic cancer is one of the most common malignant tumors in the field of urology. The number of patients is increasing rapidly and its importance as a mortal disease is gathering attention. In 1985, we organized a registration system for prostatic cancer patients found in and around Gunma prefecture. In this study, we analyzed the clinical characteristics of the 730 patients registered from 1985 to 1989. The results were as follows. Mean age was 74.0 years old and the number of the patients was the greatest in the eighth decade. Voiding disturbance was the most common chief complaint, followed by pollakisuria, gross hematuria and miction pain. Stage and grade distribution were as follows. Stage A 16.2%, B 21.1%, C 17.0%, D 45.7%, well differentiated 27.4%, moderately differentiated 48.2% and poorly differentiated 24.5%, respectively. A statistically significant relationship between stage and grade was observed. Bone was the most common metastatic site. The highest incidence of bone metastasis was in lumbar vertebra, followed by ribs, ilium, thoracic vertebra and ischium. The value of PAP, ALP and ESR tended to be higher in high stage patients, and that of Hb was lower. Fifty two patients were detected by mass screening. Most of these patients were in an early stage. Most of the patients were treated by hormonal therapy. LH-RH agonists constituted 39.2% of the cases given hormonal therapy.  相似文献   
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