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991.
992.
Spontaneous cell-mediated cytotoxicity (SCMC) and the marker of natural killer (NK) cells mediating SCMC of the human large intestine were studied. Lamina proprial lymphoid cells (LPL) were isolated by sequential dithiothreitol-EDTA-collagenase treatment of the gut specimen. SCMC was measured by the chromium release method. Target cells included P4788 in monolayer, a cell line derived from colon cancer, Chang cells in monolayer, and K562 in suspension. Target cells in monolayer including colon cancer cell line were chosen because they were thought to be more appropriate to assess SCMC for lymphoid cells in the solid organ. While lower compared to cytotoxicities (CT) by peripheral blood lymphoid cells (PBL), define CT were observed in LPL against all three targets. NK cells marker was studied both on LPL by an indirect fluorescent antibody method and on the gut tissue by indirect immunoperoxidase staining using anti HNK-1 monoclonal antibody which defines virtually all NK cells. HNK-1 positive (HNK-1 +) cells were identified in both methods. HNK-1 + cells were observed in the epithelium, lamina propria, and lymph follicle with or without germinal centers. These results clearly demonstrated the presence of SCMC and HNK-1 + cells in the human large bowel. 相似文献
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995.
An extended middle fossa approach combined with a suboccipital craniectomy to the base of the skull in the posterior fossa 总被引:2,自引:0,他引:2
A new approach to the base of the skull in the posterior fossa is described. This approach involves removing the petrous bone without any injury to the labyrinth, and dividing the superior petrosal sinus and tentorium cerebelli. A combined suboccipital craniectomy is used for excision of the portion of tumors that extended inferiorly. Total or subtotal removal of tumors was performed in 11 patients and partial removal in 3 patients, without any operative mortality. The facial nerve was preserved in all patients and hearing was retained in 9 of 12 patients. This approach is useful for large tumors located around the clivus. 相似文献
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K Yoshida S Sawada Y Tanabe Y Fujihara Y Ohta 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》1991,51(7):764-767
Gianturco expandable metallic stents were implanted into the esophagus and small intestine of 10 rabbits in order to evaluate the influence of wire stents on the gastrointestinal tract. The stents were constructed of 0.010 inch stainless steel wire. The relaxed diameter of the stents was 12-14 mm and the length was 10 mm. Except for one stent placed in the small intestine, the stents did not migrate and were covered with thickening mucosal epithelium. The mucosal inflammatory changes were slight, but severe intestinal adhesions were noted. The findings in the two groups were not significantly different at three and six weeks. Five rabbits died within three weeks of intestinal disorders caused by severe intestinal adhesions and/or perforations. The experimental data showed that implantation of metallic wire stents into the gastrointestinal tract resulted in severe damage to the esophagus and small intestine of rabbits. 相似文献
1000.
Mark Radford Ph.D. Yoshibumi Nakane M.D. Yasuyuki Ohta M.D. Leon Mann Ph.D. Ross Kalucy MBBS FRANZCP 《Psychiatry and clinical neurosciences》1989,43(2):119-132
Abstract: Recently there has emerged a growing interest in transcultural aspects of depressive disorders. Unlike earlier studies, recent research has concentrated on using standardized assessment and evaluation procedures in an effort to reduce "differences" associated with research techniques. The following paper reports a study which, using the WHO developed Standardized Assessment of Depressive Disorders (WHO/SADD) schedule, examines the nature of depressive symptomatology in Australian and Japanese clinically depressed patients. While results supported the presence of a "symptom core" common to both cultures, some unexpected findings in relation to "feelings of guilt" and "severity of depression" were noted. 相似文献