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991.
BACKGROUND: Capecitabine (Xeloda) is a novel, oral, selectively tumor-activated fluoropyrimidine with proven activity in the treatment of advanced colorectal cancer. This trial was conducted to evaluate the efficacy, safety and feasibility of capecitabine in previously untreated patients with advanced and/or metastatic gastric cancer, with a view to replacing 5-fluorouracil (5-FU) in such patients. PATIENTS AND METHODS: Forty-four patients received capecitabine 1250 mg/m2 twice daily (2500 mg/m2/day) for 14 days followed by 7 days of rest, for up to six cycles. RESULTS: Capecitabine produced an objective response rate of 34% (all partial responses) and stable disease in 14 patients (30%). The median time to disease progression (TTP) was 3.2 months [95% confidence interval (CI) 2.7-6.4 months] and median overall survival was 9.5 months (95% CI 6.9-13.2 months). Hand-foot syndrome (HFS), nausea, anorexia, diarrhea and vomiting were the most common adverse events. While HFS was the most frequent grade 3/4 toxicity (National Cancer Institute Common Toxicity Criteria), only 9% of patients experienced grade 3 HFS. Severe myelosuppression was not reported during the study. CONCLUSIONS: Capecitabine monotherapy is active and well tolerated as first-line therapy in patients with advanced/metastatic gastric cancer. Larger comparative trials investigating capecitabine-based combination regimens in patients with advanced gastric cancer are warranted.  相似文献   
992.
993.
Objective To explore the relationship between mtDNA (mitochondnal DNA) and gastric cancer by comparing the difference of mtDNA copy number in gastric cancers and paracancerous tissues. Methods The HV1 (hypervariable region) and HV2 of the mitochondrial D-loop region from 20 cases of gastric cancer and 20 paracancerous tissues were amplified by PCR with βactin serving as a quantitative standard marker. The products were separated by polyacrylamide gel electrophoresis (PAGE) and silver stained in order to compare the difference in mtDNA copy number between gastric cancers and paracancerous tissues. The mtDNA copy number was determined for gastric cancers having various pathological characteristics and the results compared with previous immunohistochemical staining of the tumors. Results There was a significantly quantitative difference in HV1, HV2 (standardized with βactin) between gastric cancers and paracancerous tissues (P<0.01 ). The mtDNA copy number was associated with important enzymes in the nucleus such as AKP, cAMP-PDE and cGMP-PDE (P< 0.05), but not associated with tumor histological type and invasive depth (P> 0.05). Conclusion The occurrence of gastric cancer was closely associated with decreased mtDNA copy number, which may be a new tumor marker. This work was supported by the research grants from the National Natural Science Foundation of China (No. 30371607).  相似文献   
994.
Lymph node mapping has become an integral part of the management of melanoma and breast cancer with regard to both staging and treatment. We report our technique for lymphatic mapping and intraoperative lymphoscintigraphy applied to a patient with penile melanoma. This technique may improve the sensitivity of identifying the sentinel lymph node in patients with malignant penile lesions.  相似文献   
995.
Liao WM  Chiu KY  Li FB  Qiu JS  Han SY  Chow SP 《Orthopedics》2000,23(11):1175-1178
Nm23 protein expression was analyzed by immunohistochemical staining using formalin-fixed, paraffin-embedded sections from 39 cases with osteosarcomas and compared with the histologic findings and early metastasis for the purpose of detecting nm23 expression in osteosarcoma and elucidating the clinical significance of its expression. Immunoreactivity of nm23 protein was detected in 48.7% of the total cases. There was no statistical difference between nm23 expression and early metastasis, but there was a trend for cases with nm23 expression to progress to early metastasis within 1 year after operation. The role of nm23 as a tumor metastasis suppressor in osteosarcomas appeared less prominent.  相似文献   
996.
The ability of three Lactobacillus strains to inhibit the adhesion and growth of naturally occurring uropathogens on silicone rubber was investigated in human urine. The importance of biosurfactant production by Lactobacillus in discouraging uropathogen growth was determined in relation to the binding affinities of the lactobacilli for silicone rubber. L. fermentum B54 markedly inhibited uropathogen growth on the silicone rubber disks after 8 days for all five men included in the study, albeit to various extents ranging from 77% to 100%. In urine from women, however, this inhibition was less clear, as it was absent for two of the four women participating in this study. L. casei rhamnosus 36 completely discouraged uropathogen growth on the disks after 8 days for three of the four women, whereas its effect in urine from men was less pronounced (inhibition ranged from 48% to 100% and was absent for one man). L. casei rhamnosus ATCC 7469T was the least inhibitory Lactobacillus strain tested and inhibition was absent for a number of both male and female participants, possibly as a result of the low binding affinity of this strain for silicone rubber and of its inability to release biosurfactants. We conclude that the inhibition of uropathogen growth is dependent on the Lactobacillus strain involved, and for L. fermentum B54 it was demonstrated to be sex-related. Hence, inhibition must be considered a multifactorial process.  相似文献   
997.
目的 探讨 CC趋化因子受体 5 (CCR5 )是否介导食管上皮炎性病变与其癌变过程的关系。方法 用免疫组化检测 40例食管鳞状细胞癌 (SCC)、癌旁炎症、不典型增生组织及 10例正常食管黏膜的 CCR5表达情况。结果 食管 SCC的 CCR5表达阳性率高于正常黏膜、慢性炎症及不典型增生的表达率 (P<0 .0 5 )。在 CCR5表达阳性的食管 SCC中 ,癌间质的单核淋巴细胞 CCR5阳性表达率分别低于癌旁炎症的单核淋巴细胞 CCR5阳性表达率(P<0 .0 5 )。结论  CCR5在食管癌变进程中表达呈升高趋势 ,提示食管 SCC细胞可能通过表达 CCR5受体与间质浸润的单核细胞、淋巴细胞共同竞争趋化因子配体 ,从而实现了食管 SCC发生进程的免疫逃逸现象  相似文献   
998.
PURPOSE: This trial tested the hypothesis that combined androgen suppression (CAS) and whole-pelvic (WP) radiotherapy (RT) followed by a boost to the prostate improves progression-free survival (PFS) by 10% compared with CAS and prostate-only (PO) RT. This trial also tested the hypothesis that neoadjuvant and concurrent hormonal therapy (NCHT) improves PFS compared with adjuvant hormonal therapy (AHT) by 10%. MATERIALS AND METHODS: Eligibility included localized prostate cancer with an elevated prostate-specific antigen (PSA) < or = 100 ng/mL and an estimated risk of lymph node (LN) involvement of 15%. Between April 1, 1995, and June 1, 1999, 1,323 patients were accrued. Patients were randomly assigned to WP + NCHT, PO + NCHT, WP + AHT, or PO + AHT. Failure for PFS was defined as the first occurrence of local, regional, or distant disease; PSA failure; or death for any cause. RESULTS: With a median follow-up of 59.5 months, WP RT was associated with a 4-year PFS of 54% compared with 47% in patients treated with PO RT (P =.022). Patients treated with NCHT experienced a 4-year PFS of 52% versus 49% for AHT (P =.56). When comparing all four arms, there was a progression-free difference among WP RT + NCHT, PO RT + NCHT, WP RT + AHT, and PO RT + AHT (60% v 44% v 49% v 50%, respectively; P =.008). No survival advantage has yet been seen. CONCLUSION: WP RT + NCHT improves PFS compared with PO RT and NCHT or PO RT and AHT, and compared with WP RT + AHT in patients with a risk of LN involvement of 15%.  相似文献   
999.
1000.
金樱子中总黄酮的提取及含量测定   总被引:17,自引:0,他引:17  
目的 从金樱子中提取总黄酮 ,并测定其含量。方法 用比色法测定金樱子中总黄酮含量。结果 测得金樱子中总黄酮含量 2 .31% ,RSD=1.95 ,平均回收率为 98.3 ,RSD=1.0 1 (n=3)。结论 首次从金樱子中提取出总黄酮 ,实验结果令人满意。  相似文献   
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