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Purposes: The study evaluates prognostic factors for dissemination and survival in patients with local or regional recurrence of breast cancer. Furthermore, the aim was to define subgroups of patients at different risk of developing metastases in specific anatomical sites. Patients and methods: The study included 140 patients with isolated local or regional node recurrence, who entered a prospective study for staging of patients with first recurrence of breast cancer in the period 1983–85. The primary treatment was a simple mastectomy; node positive patients received adjuvant radiotherapy and chemotherapy or tamoxifen.If possible, the locoregional recurrence was treated with surgery and/or radiotherapy, otherwise by systemic therapy. Results: Median follow up was 10.4 years; 78 patients developed distant metastases (soft tissue, 32%; bone, 45%; viscera 40%). Median time to dissemination was 4.4 years, and the ten year dissemination rate was 72%. Median time to dissemination was 3.7 years for patients with recurrence in the regional nodes compared to 6.5 years for patients with chest wall recurrence only, p = 0.05. No specific time sequence (temporal pattern) was observed in the anatomical distribution of metastases, and the anatomical site of recurrence could not be predicted by any of the prognostic factors. At follow up, 93 patients had died. The median survival was 5.6 years and 30% were alive after 10 years. Forty-three of the 99 patients who received local therapy only did not develop metastases. Fifteen of these patients died without evidence of metastatic disease while 28 patients were still alive without distant recurrence after a median follow up time of 9.3 years (range, 6.5–11.9 years). Level of LDH and the number of positive regional nodes (NPOS) at primary diagnosis were significant independent prognostic factors for survival after recurrence. Conclusions: Approximately one third of the patients receiving local treatment only, were alive and without distant metastases up to ten years after locoregional recurrence, indicating that there is a subset of patients which may be long term survivors after local treatment only (surgery or radiotherapy). The duration of survival can be estimated by LDH and NPOS, but the model needs validation in a separate data set before clinical use.  相似文献   
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2-Acetyl-2-decarboxamido-oxytetracycline (ADOTC) is a major impurity of oxytetracycline (OTC) produced as a side product during fermentation. ADOTC was isolated from OTC and other impurities using preparative HPLC. The preparative column was an Xterra MS, C18 chromatographic column (100 mm x 19 mm i.d., 5 microm), and the mobile phase contained methanol-water (27:73 (v/v)) with 0.08 M formic acid added. The flow rate was 9.0 ml/min. It was possible to isolate few milligram ADOTC in a day. The compound was unambiguously identified using NMR and MS-MS. The anti-microbial activity against activated sludge bacteria was determined giving a potency of only 3% of that of OTC. With tetracycline-resistant bacteria, no anti-microbial activity was observed, indicating a mode of action similar to that of OTC.  相似文献   
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