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81.
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs.  相似文献   
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83.
Eicosapentaenoic acid reduces pulmonary edema in endotoxemic rats   总被引:2,自引:0,他引:2  
BACKGROUND: Recently, eicosapentaenoic acid (EPA) was found to have an anti-inflammatory effect attributable to diminished synthesis of arachidonic acid metabolites that initiate acute lung injury. We evaluated the ability of dietary EPA supplementation to prevent endotoxin-induced acute lung injury in rats. MATERIALS ANS METHODS: Rats fed a standard diet were divided randomly into two groups: for 2 weeks one group additionally was fed 1000 mg/kg/day of EPA ethyl ester emulsion (EPA rats), while in the other group the diet was supplemented with vehicle alone (control rats). Fatty acid components of alveolar macrophages (AM) were measured, as well as leukotriene (LT) B(4) and LTB(5) production by AM exposed in vitro to calcium ionophore A23187. Plasma concentrations of thromboxane (Tx) B(2), a stable metabolite of TxA(2), were examined 1 h after inducing lung injury with endotoxin (2 mg/kg iv). At 6 h, wet/dry (W/D) weight ratios were calculated for the lungs to assess pulmonary edema, and neutrophils were counted in pulmonary parenchyma and peripheral blood. RESULTS: Arachidonic acid content and LTB(4) generation in AM were significantly lower in EPA rats than in controls; conversely, EPA content and LTB(5) generation in AM were significantly higher in the EPA group. Neutrophil counts in lung parenchyma and peripheral blood did not differ between groups, but W/D and plasma TxB(2) concentrations were significantly lower in EPA rats. CONCLUSIONS: EPA supplementation depressed arachidonic acid content and LTB(4) generation in AM and plasma TxB(2) in our model, leading to decreased pulmonary edema.  相似文献   
84.
From December 1996 to June 1998, we performed transurethral surgery of the prostate using a thick loop, VaporTome developed by Circon ACMI on 23 patients with symptomatic benign prostatic hyperplasia (BPH). The mean international prostate symptom score decreased significantly, from 22.6 at baseline to 9.0, 6.5, 4.9 and 5.3 at 1, 3, 6 and 12 months after operation, respectively. The mean quality of life index also decreased significantly, from 5.5 to 1.8, 1.8, 1.4 and 1.2, respectively. The mean peak flow rate increased significantly, from 6.2 preoperatively to 15.8, 17.1, 16.6 and 17.4 ml/sec at 1, 3, 6 and 12 months after operation, respectively. The mean prostate volume decreased significantly, from 66.9 to 24.8, 17.3, 19.0 and 18.2 ml. The mean residual urine decreased significantly, from 167.9 to 11.4, 9.4, 12.8 and 20.4 ml. As for overall efficacy, the rate of excellent and good cases at 1, 3, 6 and 12 months was 80.9, 89.4, 94.7 and 85.8%, respectively. No serious complications were observed. Our clinical results suggest that transurethral surgery for BPH using VaporTome has several potential advantages including high efficacy, minimal morbidity compared with standard transurethral resection of the prostate and lower cost compared with other minimally invasive procedures.  相似文献   
85.
We report a case of adenosquamous carcinoma of the stomach that produced granulocyte-colony stimulating factor (G-CSF). The patient, who had an admission diagnosis of advanced gastric cancer, had marked leukocytosis without evidence of infection. After leukemia and metastatic leukemoid reaction were excluded by bone marrow examination, a G-CSF-producing cancer was suspected as the cause of the abnormally elevated serum G-CSF level. The resected stomach tumor was histologically diagnosed as adenosquamous carcinoma; positive expression of G-CSF by tumor cells was shown with immunohistochemical detection, which confirmed the preoperative diagnosis. Recurrent disease in the liver and lymph nodes, accompanied by leukocytosis and re-elevation of serum G-CSF, developed just 3 months after the curative gastrectomy and adjuvant chemotherapy. All of the recurrent disease was resected, restoring normal levels of serum G-CSF. The patient survived for almost 2 years after the initial surgery with extensive chemotherapy, including weekly treatment with paclitaxel, before finally succumbing to liver failure secondary to extensive liver metastasis.  相似文献   
86.
PURPOSE: There are no available tumor markers detecting primary melanoma at an early stage. The identification of such serum markers would be of significant benefit for an early diagnosis of melanoma. We recently identified glypican-3 (GPC3) as a novel tumor marker but could diagnose only 40% of melanomas. Thereby, we focused out attention on secreted protein acidic and rich in cysteine (SPARC) overexpressed in melanoma as another candidate for tumor marker. EXPERIMENTAL DESIGN: Secreted SPARC protein was quantified using ELISA in the sera from 109 melanoma patients, five patients with large congenital melanocytic nevus, 61 age-matched healthy donors, and 13 disease-free patients after undergoing a surgical removal. We also quantified GPC3 and 5-S-cysteinyldopa in the same serum samples and compared these markers for their diagnostic value. RESULTS: The serum SPARC concentrations in melanoma patients were greater than those in healthy donors (P = 0.001). When we fixed a cutoff value at the mean concentration plus 2 SD of the healthy donors, the serum SPARC was found to have increased in the sera of 36 of the 109 (33%) melanoma patients, whereas there were three (4.9%) false-positive cases of 61 healthy donors. Surprisingly, 19 of 36 patients showing increased SPARC levels were in stages 0 to II. The serum SPARC level decreased under the cutoff level in 10 of 13 patients after surgical removal. Using SPARC and GPC3 in combination thus enabled us to diagnose 47 of 75 (66.2%) melanoma patients at an early stage (0-II). CONCLUSIONS: SPARC or its combination with GPC3 is thus considered a potentially useful tumor marker, especially for melanoma at an early stage.  相似文献   
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88.
Chondrosarcoma is the second most common primary malignant bone tumor. In this multicenter study, we sought to evaluate the disease‐specific survival (DSS) and disease‐free survival (DFS), and prognostic factors in patients with dedifferentiated chondrosarcoma (DDCS) or grade 3 chondrosarcoma (G3CS) in Japan. We retrospectively investigated the treatment outcomes and prognostic factors in 62 patients with DDCS and 19 patients with G3CS at 15 institutions participating in the Japanese Musculoskeletal Oncology Group. We also clarified significant clinicopathological factors for oncological outcomes. In surgery for primary lesions aimed at cure, a histologically negative margin (R0) was obtained in 93% (14/15) of patients with G3CS and 100% (49/49) of patients with DDCS. The 5‐year DSS was 18.5% in patients with DDCS and 41.7% in patients with G3CS (p = 0.13). Local control was obtained in 80% (12/15) and 79.6% (39/49) of patients with G3CS and DDCS in the primary lesion after surgery with a wide surgical margin, respectively. In multivariate analysis, stage and no treatment/palliative treatment for the primary lesion were independent prognostic factors for DSS of DDCS, and age and no treatment/palliative treatment for DSS of G3CS. The 5‐year DFS rate was 22.8% in 26 patients with DDCS who did not receive adjuvant chemotherapy, and 21.4% in 14 patients who received adjuvant chemotherapy. The prognosis of DDCS remains poor, although R0 resection was carried out in most cases. Effective and/or intensive chemotherapeutic regimens or agents should be considered or developed for patients with high‐grade chondrosarcoma, particularly for those with DDCS.  相似文献   
89.
90.
Branhamella catarrhalis has been misconsidered as a normal resident in human respiratory tract for a long time. However, many authors recently have reported its pathogenecity and isolated it from the otolaryngological region. In our study, this organism can be isolated from the ear and nasal discharge in the child with acute otitis media by the rate of 7.5% and 21.4% respectively. Out of this 107 isolated strains, 97 strains (90.7%) were found to be beta-lactamase producing organisms. The MIC measurement of penicillins and cephems (except CEX) for inhibition of all these strains in our study is 6.25 micrograms/ml or less and because of the unreliability of the ABPC's susceptibility test by disk method, it is necessary to check the beta-lactamase production in each strain. Becoming of the high emergence rate of beta-lactamase producing strains, B. catarrhalis should be considered to be as important pathogen as Streptococcus pneumoniae and Haemophilus influenzae in upper respiratory tract infections in children.  相似文献   
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