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991.
AIM: To define the benefit of intraoperative frozen section examination of the sentinel lymph node (sN), and to assess its prognostic value in clinically node-negative melanoma patients. MATERIALS AND METHODS: Between July 1993 and December 2001, 214 patients with Stage I-II cutaneous melanoma underwent sN biopsy; complete follow-up data are available in 169 of 175 patients who underwent preoperative lymphoscintigraphy, lymphatic mapping with Patent Blue-V and radio-guided surgery (RGS). RESULTS: In an initial subset, the sN was identified in 35 out of 39 patients; in the principal group of 169 patients, the sN was detected in all patients. The benefit of frozen section examination, that is the proportion of all patients having intraoperative histologic examination who tested positive, was 17.2% (29/169); notably, in patients with pT(1-2) vs pT(3-4) melanoma the corresponding values were 2.3 and 33.3%, respectively, (P=0.000). Cox regression analysis for overall survival indicated that sN-positive patients had a two-fold increased risk of death; the most significant predictors of relapse-free survival were sN status (P=0.004), age (P=0.015), and T stage grouping (P=0.033). CONCLUSIONS: The sN is a reliable predictor of regional lymph node status in patients with cutaneous melanoma. Frozen section examination can be useful in avoiding a 'two-stage' operative procedure in patients with tumour-positive sN, but its greatest benefit seems to be restricted to patients with pT(3)-pT(4) primary melanoma.  相似文献   
992.
BACKGROUND: Docetaxel is a new agent with activity in metastatic gastric cancer. This phase II study was designed to evaluate the activity and safety of an epirubicin, cisplatin and docetaxel combination in patients with this disease. PATIENTS AND METHODS: Forty-six patients with gastric adenocarcinoma with measurable distant metastasis were eligible for the study. Patients received epirubicin 50 mg/m(2) and docetaxel 60 mg/m(2), on day 1, and cisplatin 60 mg/m(2) on day 2. Granulocyte colony-stimulating factor 300 mug/day subcutaneously was given on days 5 and 6. Cycles were repeated every 3 weeks for a maximum of eight courses. RESULTS: All patients were evaluable for response and toxicity. Two complete and 21 partial responses were observed, with an overall response rate of 50% [95% confidence interval (CI) 36% to 64%]. Stable disease was observed in 13 patients (28%) and progressive disease in 10 patients (22%). The median time to progression was 6 months (95% CI 5-7) and the median overall survival was 11.2 months (95% CI 8.5-13.9). Grade 3/4 neutropenia, thrombocytopenia and anemia occurred in 46%, 7% and 13% of patients, respectively. There were five episodes of febrile neutropenia in four patients. Other grade 3 toxicities included mucositis in three patients (6.5%), vomiting in four patients (8.7%) and diarrhea in one patient (2%). There were no cardiac toxicity, severe neurotoxicity or treatment-related deaths. CONCLUSIONS: The epirubicin, cisplatin and docetaxel combination is an active and well tolerated novel chemotherapy regimen for treating metastatic gastric cancer and deserves further evaluation in randomized studies.  相似文献   
993.
BACKGROUND: The role of anthracyclines has been extensively studied in adjuvant chemotherapy, but much less in the primary chemotherapy of early breast carcinoma. This study, comparing CMF (cyclophosphamide, methotrexate, 5-fluorouracil) with the rotational anthracycline-containing regimen CMFEV (CMF plus epirubicin and vincristine) administered as primary chemotherapy, demonstrated a significant increase in clinical complete response in premenopausal women. We report the long-term results. PATIENTS AND METHODS: Two hundred and eleven patients with stage I or II palpable breast carcinoma and a tumour diameter of >2.5 cm were randomised to receive CMF or CMFEV for four cycles before surgery. After surgery, the patients in both arms received adjuvant CMF for three cycles. RESULTS: In the study population as a whole, there was a non-significant 20% reduction in mortality and relapse rates in the CMFEV arm. However, the effect of the experimental regimen was only found in premenopausal patients, especially in terms of relapse-free survival (P=0.07) and locoregional relapse-free survival (P=0.0009), thus mirroring the effect on response rates. After 10 years, the proportions of premenopausal patients free from locoregional relapse as a first event in the CMF and CMFEV groups were 68% and 97%, respectively. No relevant differences were found in postmenopausal patients. CONCLUSION: The overall results of this study showed that the greater activity of the experimental anthracycline-containing combination over CMF as primary chemotherapy in premenopausal patients translated into long-term effects in the same subgroup.  相似文献   
994.
PURPOSE: The purpose of this study was to investigate the safety and tolerability of MS209, a potent inhibitor of P-glycoprotein, when given in combination with docetaxel and to determine whether MS209 affects docetaxel pharmacokinetics. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were eligible for this phase I trial. Docetaxel as 1-hour infusion was given alone during the first cycle. MS209 was introduced as of cycle 2 and given orally 30 minutes after docetaxel infusion. The dose escalation scheme followed a modified Fibonacci model with six steps (docetaxel, 60-100 mg/m2 and MS209, 300-1,200 mg per body). RESULTS: A total of 30 patients were treated at five dose levels. Dose-limiting toxicities were febrile neutropenia, infection, stomatitis, dysphagia, and fatigue. The maximum tolerated dose was reached at level 5 (docetaxel, 80-MS: 1,200). Pharmacokinetic analysis failed to show a strong pharmacokinetic interaction between the two compounds, but at the highest dose levels, there is a trend to an increase of docetaxel AUC when this agent is given in combination with MS209. CONCLUSION: MS209 can be given in combination with docetaxel, with limited effect on docetaxel toxicity or pharmacokinetics.  相似文献   
995.
Referrals to genetics services are becoming increasingly common for patients who are diagnosed with early-onset colorectal cancer (CRC) or patients who have a family history of CRC. Microsatellite instability (MSI) testing and immunohistochemical analysis (IHC) of the patient’s tumor tissue, which assess indirectly the cellular status of DNA mismatch repair, have proven important tools for geneticists and genetic counselors to determine whether or not these individuals may be at risk for an inherited cancer syndrome, Lynch syndrome (a subset of hereditary nonpolyposis colorectal cancer). The application of tumor MSI/ IHC also extends to the group of providers involved in the diagnosis and management of CRC, demonstrating the growing clinical applicability of MSI/IHC testing. This review discusses the clinical utility of MSI/IHC analysis, including its benefits and limitations, and addresses some of the current debates surrounding testing.  相似文献   
996.
NAD(P)H:quinone oxidoreductase 1 (NQO1) is a detoxification enzyme that protects cells against oxidative stress and toxic quinones. A polymorphism (C609T) in the gene produces in the heterozygous individuals (C/T) a reduction and in those homozygous for the variant allele (T/T) the abolishment of NQO1 protein activity. To assess whether NQO1 inactivating polymorphism (CT/TT) was a possible risk factor for infant acute lymphoblastic leukemia (iALL), we investigated the distribution of NQO1 genotype in 50 iALL patients, 32 with MLL gene rearrangements (MLL+) and 18 without (MLL-). As controls, 106 cases of pediatric ALL (pALL), and 147 healthy subjects were also studied. Compared to normal controls, the frequency of the low/null activity NQO1 genotypes was significantly higher in the iALL MLL- (72 vs 38%, P=0.006; odds ratio (OR) 4.22, 95% confidence interval (CI) 1.43-12.49), while no differences were observed in iALL MLL+ (44 vs 38%, P=0.553; OR 1.26, 95% CI 0.58-2.74). Similar results were observed when pALL were used as control. Our results indicate that only the iALL patients without MLL rearrangements had a significantly higher frequency of NQO1 genotypes associated with low/null activity enzyme, suggesting a possible role for NQO1 gene as an MLL-independent risk factor, in the leukemogenic process of this subtype of iALL.  相似文献   
997.
The vast majority of new cases of colorectal cancer, the second most common cause of death in men and women in the United States, are attributable to environmental rather than genetic causes. Recent research has clarified inconsistencies in the literature and has explored new pathways through which risk factors may act. This review discusses newly published, selected interesting and important findings in colorectal cancer etiology; these include postmenopausal hormone use, nonsteroidal anti-inflammatory drug use, obesity, physical activity, diet, and other confirmed epidemiologic associations. This research provides insight into mechanisms and offers opportunities for prevention.  相似文献   
998.
999.
1000.
T型钙通道在心肌肥厚大鼠心肌细胞钙内流中的作用   总被引:2,自引:0,他引:2  
目的研究T型钙通道在心肌细胞钙离子内流中的作用及其对心脏兴奋收缩耦联的可能影响。方法测定选择性T型钙通道阻滞剂米贝拉地尔对培养的SD乳大鼠心室肌细胞和二肾一夹心肌肥厚大鼠心室肌细胞[Ca2+]i的影响。结果血管紧张素Ⅱ(AngⅡ)刺激使乳大鼠心室肌舒张期细胞[Ca2+]i增高,收缩期细胞[Ca2+]i降低,[Ca2+]i上升和下降的时间延长。米贝拉地尔1.25~5μmol·L-1浓度依赖性降低AngⅡ引起的细胞[Ca2+]i变化。在心肌肥厚模型大鼠,咖啡因刺激后,[Ca2+]i增幅和最高[Ca2+]i明显降低。而米贝拉地尔25mg·kg-1·d-1(灌胃给药7~9周)组加入咖啡因刺激后细胞内[Ca2+]i增幅和最高[Ca2+]i明显增高。结论T型钙通道异常开放可以引起心肌细胞内钙超载。阻断T型钙通道,可能通过改善肌浆网摄取及释放钙的功能而抑制心肌细胞钙超载。  相似文献   
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