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31.
We describe herein a rare case of primary malignant melanoma of the rectum in an 85-year-old woman. The patient presented with intermittent rectal bleeding, and a colonoscopy revealed an ulcerated polypoid mass in the rectum, located 5 cm from the anal verge. The lesion was histologically characterized by solid growths of small round cells with scanty cytoplasm and prominent nucleoli. Although no melanin pigment was found in the tumor cells, they were immunohistochemically positive for HMB-45, a monoclonal antibody highly specific for malignant melanoma. Thus, HMB-45 proved very useful to establish a diagnosis of amelanotic malignant melanoma of the rectum.  相似文献   
32.
Perioperative tumor localization for laparoscopic colorectal surgery   总被引:4,自引:3,他引:1  
Background: Because of the inability to palpate colonic tumors during laparoscopy, their location must be precisely identified before resection is undertaken. Method: A retrospective study was performed of 58 patients in order to be able to describe our methods of tumor localization for laparoscopic colorectal operations and to review their effectiveness. Results: In all patients, the entire colon was examined preoperatively by colonoscopy. In one patient, preoperative colonoscopic localization was inaccurate. In 31 patients, tumors were easily detectable at surgery. In five patients with the tumor in the right colon, even though the lesion was not detectable at surgery, right colectomy was performed without marking because preoperative colonoscopy reliably identified the lesion adjacent to the ileocecal valve. Twenty-two patients required some type of procedure to localize the tumor. The procedures and their problems were as follows: preoperative tattoo (five)—tattoo not visualized (one); intraoperative colonoscopy alone (six), combined with intraoperative tattoo (four) or clip (three)—poor operative exposure due to bowel distension (nine), hard to see the clip (three), dislodged clip (two), inadequate resection margin (one); intraoperative proctoscopy alone (two), combined with laparoscopic stitch (two)—no problems. In no patient was tumor present at a resection line and in no patient was the wrong segment resected. Conclusions: Reliable preoperative identification of the tumor adjacent to the ileocecal valve can permit right colectomy without marking. Lesions in the upper rectum can be approached via intraoperative proctoscopy ± suture placement. If the surgeon anticipates intraoperative localization may be difficult, lesions other than rectal or cecal ones should probably be marked by preoperative tattooing. Further studies regarding the technique of tattooing are warranted. Received: 18 July 1996/Accepted: 10 March 1997  相似文献   
33.
To determine the anomeric preference of uptake of D-glucose and of D-galactose by rat lenses, we crystallized alpha-, beta-D-[U-14C]glucose (720 microCi/mmol) and alpha-, beta-D-[U-14C]galactose (180 microCi/mmol) by our method and incubated them separately with rat lenses for 1 min, because of the short half-life of mutarotation of alpha-D-glucose (9.6 min) and of alpha-D-galactose (4.6 min) in HEPES medium at 30 degrees C. During aerobic incubation of rat lenses in HEPES medium containing radioactive alpha or beta anomer of D-glucose, there was no significant difference in the rate of uptake between alpha and beta anomers of D-glucose by rat lenses. However, 1.59 times greater incorporation of alpha-D-galactose was observed over that of beta-D-galactose under the same conditions.  相似文献   
34.
Fourteen strains of Eikenella corrodens isolated from human oral cavity were studied to determine corroding characteristics. Nine out of the 14 strains produced corroding colonies under anaerobic culture condition. One of them produced corrosion even in an aerobic culture. No morphological differences in surface structures were observed between corroding and non-corroding strains of E. corrodens by transmission electron microscopy. The morphology of corroding colonies of E. corrodens was then examined by scanning electron microscopy. The surface of the corroding-colony center was smoothly convex. A boundary line was clear between the smooth center and the surrounding corrosion region. Double or triple frill-like structures surrounded the center portion with small convexities. Spreading bacterial masses were observed in the outer portion of the colony. Morphological observations of the corroding colony edge indicated that a surface translocation termed "twitching motility" or "gliding motility" occurs in the outer portion and plays a role in its colonization of periodontal regions.  相似文献   
35.
Key words  intractable pain - celiac plexus neurolysis - ultrasonography  相似文献   
36.
Summary Physicochemical properties of two types of adriamycin preparation, suspensions and emulsions prepared for i.a. chemotherapy of hepatocellular cacinoma, were investigated. A suspension was prepared by dispersing adriamycin directly into the lipid contrast medium, Lipiodol, whereas an emulsion was obtained by emulsifying an aqueous solution of adriamycin into Lipiodol. The dispersibility of the drug in each preparation was examined microscopically. The chemical stability of and drug release from the preparation were determined by high-performance liquid chromatography and spectrophotometry, respectively. The suspension was then given to ten patients with primary hepatocellular carcinoma. The suspension maintained good dispersibility without coagulation of drug particles, whereas coalescence of aqueous droplets and the resultant phase separation occurred 4 h after preparation of the emulsion. Both preparations maintained the initial drug content for at least 1 week at room temperature. The release of adriamycin was more prolonged in the suspension than in the emulsion. After i.a. administration of the suspension, a selective accumulation of Lipiodol in the tumor and decrease in serum -fetoprotein (AFP) levels were found in most patients. A significant amount of adriamycin was still detected in hepatic speciments resected from two patients 1 and 2 months after treatment. These findings suggest that the adriamycin-Lipiodol suspension may be a useful preparation for targeting chemotherapy to hepatocellular carcinoma.  相似文献   
37.
38.
Mononuclear cells in pleural fluid from patients with tuberculous pleurisy were predominantly T cells. Responsiveness of pleural fluid T cells to purified protein derivative of tuberculin were studied by the assay of cell proliferation and production of lymphocyte mitogenic factor by the stimulation with purified protein derivative. Peripheral blood lymphocytes were also studied from patients and tuberculin-positive healthy controls. The order of responsiveness was as follows: pleural fluid lymphocytes greater than peripheral blood lymphocytes of patients without effusion = peripheral blood lymphocytes of healthy controls greater than peripheral blood lymphocytes of patients with effusion. The poor response of peripheral blood lymphocytes from pleurisy patients were recovered by the elimination of adherent cells in peripheral blood lymphocytes to the level of the response of peripheral blood lymphocytes from healthy controls. T cells purified from pleural fluid mononuclear cells responded more than those from peripheral blood. These results suggested that in the pleurisy patients purified protein derivative-reactive T cells in peripheral blood did not decrease in activity, but were depressed by suppressor cells, and further suggested that highly purified protein derivative-reactive T cells were accumulated in the pleural fluid.  相似文献   
39.
40.
Summary In order to explore the relationship between the expression of cancer-associated glycolipids such as sialylated Lex (SLEX) and sialylated Lea (SLEA) and the histological subtypes of lung cancers, 30 cases of small cell carcinoma (SCC) and 47 cases of non-small cell carcinoma (non-SCC) were examined immunohistochemically using monoclonal antibodies reacting with SLEX and SLEA. The forty-seven cases of non-SCC included 20 cases of adenocarcinoma, 20 of squamous cell carcinoma and 7 of large cell carcinoma. Tumour cells of most non-SCCs expressed SLEX and SLEA. In adenocarcinomas, the number of tumour cells having SLEX and SLEA was more than that of squamous cell carcinomas, large cell carcinomas and SCC. In SCC, 14 of the 30 cases were found to be positive for both antigens. Although the cancer cells of 11 cases of 17 intermediate cell type SCC had both antigens, the cells of only 3 of 13 oat cell tumours expressed SLEX and SLEA. The present study shows that SLEX and SLEA are useful markers for lung adenocarcinomas, that most cases of intermediate cell type of SCCs have characteristics similar to non-SCC but that many oat cell tumours lack them.  相似文献   
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