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41.
PURPOSE: To analyze the management and clinical outcome of patients treated for a first isolated local recurrence of soft tissue sarcomas (trunk or extremities) and to identify prognosis factors. METHODS AND MATERIAL: Between 1980 and 1999, 83 adult patients were included in the study. Mean age was 61 years. Mean tumor size was 6 cm. Most sarcomas were located in extremities (n=74), were deep (n=60), and proximal (n=53); 30 involved nerves or vessels. Histologic subtypes were mainly grade 2 (42%) or 3 (36%) histiocytofibrosarcomas (49%) and liposarcomas (20%). Surgical treatment of recurrences consisted in wide excision (29 cases), marginal resection (43 cases), 5 patients requiring amputation. Final results were R0 (n=33), R1 (n=47) or R2 (n=3) resection. Besides surgery, 6 patients received neo-adjuvant and 7 others adjuvant chemotherapy. Twenty three patients received post-operative external beam radiotherapy (EBRT) (mean dose 55 Gy) and 26 interstitial 192Ir low dose rate brachytherapy (BCT) (mean dose 45 Gy for BCT alone, 22 Gy when associated with EBRT), 19 patients being re-irradiated. RESULTS: Mean follow up was 13 years. Thirty-seven (45%) patients relapsed, 62% of whom presenting an isolated local recurrence. Nineteen patients developed distant metastases. Multivariate analysis showed only tumor depth (P=0.05) and re-resection for primary R1 resection (P=0.018) being independent prognosis factors for tumor control, radiotherapy (EBRT and/or BCT) being significant in univariate analysis (P=0.05). Overall survival rate was 73%, 54%, and 47% at, respectively, 3.5 and 10 years, and was 65%, 35% and 32% after a further local recurrence. Multivariate analysis showed trunk (P=0.0001) or inferior extremity locations (P=0.023), symptomatic (P=0.001), high grade (P=0.01), deep (P=0.01) tumors, and the occurrence of a further local failure (P=0.004) as unfavorable characteristics for overall survival. CONCLUSIONS: A first isolated local recurrence of STS increases mainly the risk of a subsequent local relapse. Quality of local treatment is decisive. When a conservative treatment is feasible, it should combine surgical resection and radiotherapy, BCT being the best suited in previously irradiated patients. Efforts have to be pursued to increase quality of the treatment of primary tumors, at best performed in centers that have expertise in this field.  相似文献   
42.
Objective. The purpose of this paper is to review and categorize the CT appearances of primary and secondary intraperitoneal neoplasms in children. Materials and methods. We retrospectively reviewed the CT images of 14 cases of intraperitoneal neoplasms. They were reviewed for bowel wall thickening, mesenteric nodules, ascites, calcification, peritoneal nodules, omental caking, and contrast enhancement. Results. Computed tomography images of 14 cases of intraperitoneal neoplasms were evaluated: rhabdomyosarcoma (5), lymphoma (3), neuroblastoma (2), germ cell tumor (1), mesothelioma (1), Wilms tumor (1), and hepatocellular carcinoma (1). Nodular enhancement was seen in all cases, ascites in most, significant bowel wall thickening only with lymphoma, and calcification only with germ cell tumors. Omental caking was present both with rhabdomyosarcoma and lymphoma. Conclusions. While rare in pediatrics, intraperitoneal neoplasms occur in children, and CT is useful in identifying these peritoneal neoplasms. Received: 7 August 1997 Accepted: 9 December 1997  相似文献   
43.
Studies have shown family planning adoption is likely to be more effective for women when men are actively involved. The transtheoretical model of behavior change was used to examine men's involvement in general contraception and intrauterine device (IUD) use by their wives. The study was carried out in rural Vietnam with 651 eligible participants. Cons of IUD use for men in precontemplation and contemplation/preparation were significantly higher than those in the action/maintenance stages, whereas the reverse was true for pros of IUD. The self-efficacy for convincing wife to have IUD in precontemplation was significantly lower than for those in higher stages. Women's education and ages, spontaneous recall of modern contraceptive method, cons for IUD, and self-efficacy for contraception and for convincing wives to get IUD inserted (or continue use) were significant predictors of men's readiness to accept IUD. Interventions are targeted to reduce cons and increase self-efficacy for IUD use.  相似文献   
44.
PURPOSE: To evaluate retrospectively the anatomical definition of target volumes in the treatment of soft tissue sarcomas of the limbs and to study the radiation dose in the local control and toxicity. METHODS AND PATIENTS: Seventy-seven patients were consecutively treated for primary soft tissue sarcoma of the extremity with limb sparing surgery and external beam radiotherapy (EBRT) in the same institution. The median follow up was 56 months (17-89 months). RESULTS: Fifty-two patients (67%) had clear microscopic surgical margin (R0 resection), 23 (30%) had histologically positive microscopic margin (R1 resection), 2 had a macroscopic residual disease (R2 resection). An anatomical definition of target volumes has been realised. The mean dose was 50 Gy in 25 or 28 fractions; 23 patients received a boost restricted to the tumor bed: 13 with EBRT, 10 with brachytherapy (BRT). Thirty-four patients had an adjuvant chemotherapy. The overall 5 year local relapse rate was 10%. Seven local relapses were described, five of the high-grade tumours, and five in patients with positive margin. In univariate analysis, quality of surgery shows a significant effect for local control. By using LENT-SOMA scale for late toxicity, a significant difference was found for neurological complications for patients receiving a boost. CONCLUSIONS: The results of the series validate the concept of anatomical definition of the initial target volume. A boost should be realised for positive margin tumors and may be for high-grade tumors. Neurological toxicity must be considered for the evaluation of the prescribed dose.  相似文献   
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The CD44 receptor, which is upregulated in many cancer cells, provides a selective cellular surface for targeted drug delivery systems. We developed a hybrid nanocarrier for the CD44-targeted delivery of ibuprofen (IBU) and paclitaxel (PTX). The solid lipid nanoparticles (SLNs) were prepared by a hot-melt oil/water emulsion technique and then coated with hyaluronic acid (HA) by electrostatic interactions. The final SLN were spherical with a hydrodynamic diameter (Z) of 72.16 ± 2.9 nm, polydispersity index (PDI) of 0.276 ± 0.009, and zeta potential (ZP) of 28.20 ± 0.69 mV. Similarly, SLN coated with HA (SLN-HA) exhibited acceptable physical properties (Z 169.3 ± 0.55 nm, PDI 0.285 ± 0.004, and ZP ? 10.5 ± 0.15 mV). Cell viability assays showed that the combination of IBU, a chemopreventive agent, and PTX exerted a synergistic inhibitory effect on the proliferation of cancer cells (CI < 1.0). Additionally, our observations indicated that both SLN and SLN-HA enhanced apoptosis and cellular uptake compared to the cocktail of free drugs. HA indicated its affinity for cancer cells through the improvement of cellular uptake and induction of apoptosis. These results clearly indicated that these nanoparticle systems hold great promise for drug delivery in breast cancer treatment.  相似文献   
47.
48.
Recent immigrant Latinas are at increased risk of poor mental health due to stressors associated with adapting to life in the United States. This study evaluated Amigas Latinas Motivando el Alma, a promotora intervention to reduce stress and promote health and coping among recent immigrant Latinas. Using a pre- and post-test design, we evaluated mental health outcomes, specifically, in promotoras. Promotoras’ knowledge levels related to role of promotora and stress management increased, depressive symptoms and stress levels decreased, and coping responses and perceived social support increased as well. Results suggest that promotora programs may be an effective way to improve mental health in recent immigrant Latinas.  相似文献   
49.
Nine microsatellite loci were isolated and characterized in the tire track eel, Mastacembelus favus by using library enriched for microsatellite region. Among 47 specimens collected from Mekong River, the number of alleles ranged from 2 to 17 while levels of observed and expected heterozygosities ranged from 0.021 to 0.873 and from 0.021 to 0.893, respectively. The primers were successfully tested in six closely related species, hence valuable for investigating population genetics and other related aspects of M. favus and its congener species.  相似文献   
50.
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