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991.
The authors assess the incidence of locoregional chronic pain after inguinal hernia repair. One hundred consecutive patients, with a mean age of 65.4 years, suffering from primary monolateral inguinal hernia, underwent suture-less mesh-plug hernioplasty. In all cases the inguinal nerves were identified. In the early postoperative period, a questionnaire was given to all patients in order to assess the frequency, type and intensity of postoperative locoregional pain and the impact of the pain on their quality of life. Sixty patients were available for follow-up with clinical examination and these were given the same questionnaire 2-4 years after hernioplasty. Pain intensity was scored by means of a visual-analogue scale (from 0 to 10). The incidence of locoregional pain after hernioplasty was 13.0% in the early postoperative period and 25.0% after a longer period of follow-up. None of the patients presented recurrent hernia. The symptomatic patients reported mild or moderate neurogenic pain. Severe pain was not reported. On the whole, the presence of mild-to-moderate chronic pain had no impact on the patients' quality of life. Our study confirms the high incidence of locoregional chronic pain even after sutureless mesh-plug hernioplasty, but that this has no serious effects on the patients' quality of life.  相似文献   
992.
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994.
Purpose. To evaluate the activity and toxicity of gemcitabine and vinorelbine (GemVin), in patients with advanced breast cancer, previously treated with anthracyclines alone or with taxanes. Patients and methods. Nine patients were entered into the phase I and 50 patients were entered into the phase II study. Gemcitabine was administered beginning with the dose of 800 mg/m2 and vinorelbine was given at the fixed dose of 25 mg/m2, both on days 1 and 8, every 21 days. Escalated dose levels of gemcitabine were planned by increments of 200 mg/m2 per level. The median age of the 50 assessable patients for the phase II study was 56.5 years (range 30–70) and median performance status (PS, ECOG score), 1 (range 0–2). The dominant sites of metastases were viscera in 40, bone in five and soft tissue in five patients. First-line chemotherapy for metastatic disease with taxanes and anthracyclines or with anthracyclines alone was administered in 36 and 14 patients, respectively. Results. The optimal schedule for the combination was gemcitabine 800 mg/m2 and vinorelbine 25 mg/m2. The maximum tolerated dose of gemcitabine was 1000 mg/m2, with grade 4 neutropenia occurring in two cases at this dose level. Overall, 267 cycles were given to the 50 patients enrolled into the phase II (mean 5.3; range 3–9). The schedule was well tolerated: three patients experienced grade 4 neutropenia and another four patients experienced grade 3 anemia. Non-hematological toxicities were moderate. A major objective response was observed in 42% of patients (95% confidence interval (CI), 28–57%), with complete remission in four (8%) and partial response in 17 (34%) patients. The median time to progression was 6 months. Activity as well as toxicity were similar in the subgroups of the patients pretreated either with combinations of taxanes and anthracyclines or anthracyclines alone. Conclusions. The optimal GemVin schedule is an effective and well tolerated second-line therapy in patients with metastatic breast cancer pre-treated with anthracycline – based schedules or with combinations of anthracyclines and taxanes.  相似文献   
995.
Urokinase-type plasminogen activator (u-PA) plays a key role in malignant tumor behavior. We have previously shown that the expression of high levels of u-PA mRNA in human hepatocellular carcinoma (HCC) biopsies was inversely correlated with the survival of the patients. In order to evaluate the involvement of u-PA in the invasive and infiltrating properties of HCC cells, the SKHep1C3 cell line was stably transfected with an expression vector containing the 5' portion (257 bp) of u-PA cDNA in the antisense orientation. u-PA mRNA expression and its protein level and enzymatic activity were specifically inhibited in the antisense transfectants. A comparable inhibition of the u-PA receptor (u-PAR) mRNA and protein was also evidenced in the antisense transfected cells compared with the control ones. At the functional level, the SKHep1C3-AS cells showed a significant reduction in proliferation, Matrigel invasion, and motility assays compared to parental and vector-alone cells. These results indicate that u-PA is an essential factor in the growth and invasiveness of human hepatocarcinoma cells. Antisense u-PA strategy might be a potential approach to reduce tumor growth as well as the invasive capacity of the malignant cells in HCC.  相似文献   
996.
Synthetic ribozymes are catalytic RNA molecules designed to inhibit gene expression by cleaving specific mRNA sequences. We investigated the potential of synthetic ribozymes to inhibit bcl-2 expression in apoptosis defective bcl-2 overexpressing tumors. A chemically stabilized hammerhead ribozyme has been targeted to the A+U-rich regulative element of bcl-2 mRNA that is involved in bcl-2 gene switch-off during apoptosis. The design of the ribozyme was based on the results of probing accessibility of the RNA target in cellular extracts with antisense DNA. The ribozyme was lipotransfected to a bcl-2 overexpressing human lymphoma cell line (Raji). The cellular uptake of this ribozyme resulted in a marked reduction of both bcl-2 mRNA and BCL-2 protein levels and dramatically increased cellular death by apoptosis. Our results suggest a potential therapeutic application of such ribozyme for the treatment of bcl-2 overexpressing tumors.  相似文献   
997.
The ErbB-2 interacting protein receptor-associated late transducer (RALT) was previously identified as a feedback inhibitor of ErbB-2 mitogenic signals. We now report that RALT binds to ligand-activated epidermal growth factor receptor (EGFR), ErbB-4 and ErbB-2.ErbB-3 dimers. When ectopically expressed in 32D cells reconstituted with the above ErbB receptor tyrosine kinases (RTKs) RALT behaved as a pan-ErbB inhibitor. Importantly, when tested in either cell proliferation assays or biochemical experiments measuring activation of ERK and AKT, RALT affected the signalling activity of distinct ErbB dimers with different relative potencies. RALT deltaEBR, a mutant unable to bind to ErbB RTKs, did not inhibit ErbB-dependent activation of ERK and AKT, consistent with RALT exerting its suppressive activity towards these pathways at a receptor-proximal level. Remarkably, RALT deltaEBR retained the ability to suppress largely the proliferative activity of ErbB-2.ErbB-3 dimers over a wide range of ligand concentrations, indicating that RALT can intercept ErbB-2.ErbB-3 mitogenic signals also at a receptor-distal level. A suppressive function of RALT deltaEBR towards the mitogenic activity of EGFR and ErbB-4 was detected at low levels of receptor occupancy, but was completely overcome by saturating concentrations of ligand. We propose that quantitative and qualitative aspects of RALT signalling concur in defining identity, strength and duration of signals generated by the ErbB network.  相似文献   
998.
Differential expression of galectin-3 in pituitary tumors   总被引:24,自引:0,他引:24  
Galectin-3 (Gal-3), a beta-galactoside-binding protein, has been implicated in a variety of biological functions, including cell proliferation and differentiation, tumor cell adhesion, angiogenesis, apoptosis, tumor progression, and metastasis. We investigated the role of Gal-3 in the development and progression of pituitary tumors. Immunohistochemical and Western blot analysis of normal and neoplastic human pituitaries showed that only lactotroph (PRL) and corticotroph (ACTH) hormone-producing cells and tumors expressed Gal-3. Gal-3 was present in 24 of 38 (63.2%) PRL adenomas, 5 of 6 (83.3%) PRL carcinomas, 19 of 41 (46.3) ACTH adenomas, and 7 of 8 (87.5%) ACTH carcinomas, but not in 112 other pituitary adenomas and carcinomas. Pituitary folliculo-stellate cells, which have macrophage-type functions in the anterior pituitary, also expressed Gal-3. Hyperplastic and neoplastic pituitaries from p27(Kip1) (p27)-null mice, which produce mainly ACTH, showed increased Gal-3 expression levels compared with control mice. Treatment with transforming growth factor beta1, which regulates pituitary cell proliferation, reduced Gal-3 as well as p27 expression levels in cultured HP75 pituitary cells and Gal-3 in cultured pituitary cells from p27-null mice, suggesting that p27 is not necessary for the inhibitory effects of transforming growth factor beta1 on the cell cycle in the pituitary. The role of Gal-3 in pituitary cell function was examined by RNA interference experiments. Inhibition of Gal-3 gene expression by RNA interference decreased HP75 cell proliferation and increased apoptosis. These results indicate that Gal-3 has an important role in pituitary cell proliferation and tumor progression.  相似文献   
999.
BACKGROUND: Adjuvant chemotherapy has been suggested as a possible strategy to improve survival in women with early-stage ovarian cancer; however, all randomized studies to date have been too small to answer this question reliably. METHODS: We performed a preplanned combined analysis of two parallel randomized clinical trials (International Collaborative Ovarian Neoplasm 1 [ICON1] and Adjuvant ChemoTherapy In Ovarian Neoplasm [ACTION]) in early-stage ovarian cancer that compared platinum-based adjuvant chemotherapy with observation following surgery. Between November 1990 and January 2000, 925 patients (477 in ICON1 and 448 in ACTION) who had surgery for early-stage ovarian cancer were randomly assigned to receive platinum-based adjuvant chemotherapy (n = 465) or observation (n = 460) until chemotherapy was indicated. Kaplan-Meier analysis was used to compare overall and recurrence-free survival by treatment allocation. In subgroup analyses of pretreatment age, tumor stage, histologic cell type, and differentiation grade, the differences in relative size of effect were tested using a chi-square test for interaction or a chi-square test for trend. All tests of statistical significance were two-sided. RESULTS: After a median follow-up of over 4 years, 245 patients had died or had a recurrence (ICON1: 133, ACTION: 112). Overall survival at 5 years was 82% in the chemotherapy arm and 74% in the observation arm (difference = 8% [95% confidence interval (CI) = 2% to 12%]; hazard ratio [HR] = 0.67, 95% CI = 0.50 to 0.90; P =.008). Recurrence-free survival at 5 years was also better in the adjuvant chemotherapy arm than it was in the observation arm (76% versus 65%, difference = 11% [95% CI = 5% to 16%]; HR = 0.64, 95% CI = 0.50 to 0.82; P =.001). Subgroup analyses provided no evidence of a difference in the size of effect of chemotherapy on survival in any pretreatment subcategory. CONCLUSIONS: Platinum-based adjuvant chemotherapy improved overall survival and recurrence-free survival at 5 years in this combined group of patients with early-stage ovarian cancer defined by the inclusion criteria of the ICON1 and ACTION trials.  相似文献   
1000.
BACKGROUND: Decitabine is a hypomethylating agent that has activity in patients with leukemia. The authors combined decitabine with busulfan and cyclophosphamide as a conditioning regimen prior to allogeneic hematopoietic stem cell transplantation. METHODS: Patients with high-risk acute myeloid leukemia (AML) (n = 12 patients); chronic myelomonocytic leukemia (CMML) (n = 1 patient); acute lymphocytic leukemia (ALL) (n = 1 patient); or late chronic phase, accelerated, or blastic phase chronic myelogenous leukemia (n = 9 patients) were eligible for the study. The treatment plan was comprised of busulfan, 12 mg/kg orally; cyclophosphamide, 100 mg/kg (n = 4 patients) or 120 mg/kg (n = 19 patients); and decitabine, intravenously at 3 dose levels: 400 mg/m(2) (n = 10 patients), 600 mg/m(2) (n = 8 patients), and 800 mg/m(2) (n = 5 patients). Donors were human leukocyte antigen-identical siblings in all cases, and all but one patient received peripheral blood stem cells. Graft-versus-host disease (GVHD) prophylaxis was tacrolimus based in all but one patient. RESULTS: The median time to neutrophil and platelet engraftment was 12.5 days and 17.5 days, respectively. Twenty-one patients were engrafted and achieved disease remission. At a median of 3.3 years posttransplantation, 26% of patients (40% of patients with AML) were alive and disease free. The median survival for the group was 17.2 months, and the disease free survival for the group was 8.9 months. Causes of death were disease recurrence (nine patients), chronic GVHD (four patients), infections (three patients), and acute GVHD (one patient). The 100-day mortality rate was 9%. No decitabine dose-limiting toxicity was documented. The treatment-related mortality rate at 3 years was 35%. Responders were treated at all three decitabine dose levels, and no dose-response correlation was observed. CONCLUSIONS: There was a high response rate with low treatment-related mortality, with 26% of patients alive in remission 3.3 years after transplantation.  相似文献   
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