首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   15篇
  免费   2篇
  2022年   1篇
  2021年   1篇
  2016年   1篇
  2014年   1篇
  2013年   6篇
  2012年   1篇
  2007年   1篇
  2004年   1篇
  2003年   1篇
  1990年   2篇
  1983年   1篇
排序方式: 共有17条查询结果,搜索用时 15 毫秒
1.
In a panel of 18 colon cancer cell lines we found that the thymidylate synthase (TS) genotype was related to TS enzyme activity, but not to TS protein and mRNA levels. In addition, no relation with drug sensitivity was observed. TS genotyping of different tissues from 78 colorectal cancer patients revealed a high level of homology in polymorphic status between normal and malignant tissues and the heterozygous genotype to be the most frequent.  相似文献   
2.
A novel water-soluble chitosan derivative [N-(2-carboxybenzyl)chitosan, CBCS] was synthesized. The chemical structure of CBCS was characterized by FTIR, (1)H NMR and UV spectroscopies. The degree of substitution (DS) of N-2-carboxybenzyl was determined by colloid titration. In different pH buffer solutions, the swelling characteristics of hydrogels based on CBCS (CBCSG) prepared by crosslinking with glutaraldehyde have been studied. Results showed that the swelling ratio (SR) of CBCSG decreased with an increase of the amount of glutaraldehyde, and that CBCSG swelled more significantly in alkaline solution than in acidic medium, showing the lowest SR at pH5.0. The SR of CBCSG increased with the raising of the DS of the N-2-carboxybenzyl group in alkaline solution, but no significant change was observed in an acidic environment. CBCSG showed swelling reversibility when alternately soaked in pH1.0 and 7.4 buffer solutions. Release profiles of fluorouracil (5-FU), a poorly water-soluble drug, from CBCSG were studied under both simulated gastric and intestinal pHconditions. The release was much quicker in pH7.4 buffer than in pH1.0 solution. Results indicated that CBCS could be a potential pH-sensitive carrier for colon-specific drug delivery system.  相似文献   
3.
摘要 目的:探讨奥沙利铂和氟尿嘧啶联合贝伐珠单抗对晚期胃癌患者免疫功能、肿瘤标志物和预后的影响。方法:选取2014年3月到2017年5月期间我院收治的晚期胃癌患者62例,根据住院号单双数分为对照组和观察组,各31例。对照组给予奥沙利铂和氟尿嘧啶治疗,观察组在对照组的基础上联合贝伐珠单抗治疗,对比两组临床有效率、免疫功能、肿瘤标志物、不良反应和预后。结果:观察组治疗后的临床有效率较对照组高(P<0.05)。两组治疗后免疫球蛋白(Ig)A、IgG、CD4+/CD8+、CD4+、IgM均升高,且观察组高于对照组(P<0.05),两组治疗后CD8+均降低,且观察组低于对照组(P<0.05)。两组治疗后癌胚抗原( CEA) 、糖类抗原199(CA199)、糖类抗原72-4(CA72-4)均降低,且观察组低于对照组(P<0.05)。观察组的不良反应总发生率较对照组低(P<0.05)。观察组复发率、癌症转移率低于对照组,且3年生存率高于对照组(P<0.05)。结论:奥沙利铂和氟尿嘧啶联合贝伐珠单抗治疗晚期胃癌患者,可有效缓解病情,提高免疫功能,同时还降低不良反应发生率,获得良好的预后。  相似文献   
4.
The insufficient penetration through the cell membranes is one of the major drawbacks of chemotherapeutics such as 5‐fluorouracil (5‐FU; 1 ). To improve the penetration, a useful strategy is the attachment of lipophilic moieties. Thus, we have synthesized a series of nucleolipid derivatives of 5‐fluorouridine (5‐FUrd; 2a ), carrying lipophilic moieties at N(3) and/or at the 2′,3′‐O position, i.e., 3a, 3b, 4 – 7 , and tested their cytostatic/cytotoxic activities towards three carcinoma cell lines (colon (HT‐29), hepatocellular (HepG2), and renal (RENCA)) in comparison with 5‐FU ( 1 ) and 5‐FUrd ( 2a ). After 48 h of incubation, four derivatives, 3a, 3b, 5 , and 7 , showed inhibitory effects on the survival of HT‐29, HepG2, and RENCA cells. Additionally, to differentiate between anticancer and side‐effects, we tested the cytotoxicity of the derivatives in human macrophages. Interestingly, the derivatives 4, 5 , and 6 did not exhibit any effects on survival of THP‐1 macrophages. Furthermore, we investigated the apoptosis induction of compound 1 and 2a , and the above‐mentioned derivatives in HT‐29 cells. Derivative 5 showed the highest significant (p<0.05; p<0.01) increase of the apoptosis at 80 μM after 2‐h or 4‐h treatment, as well as after 6‐h incubation at 40 μM (p<0.05). Real‐time PCR revealed that 40‐μM derivative 5 showed a 1.8‐fold increase of the pro‐apoptotic caspase‐3 gene and a twofold significant increase (p<0.01 and p<0.05 vs. control and 1 , resp.) of the tumor suppressor TP53 gene, whereas the other compounds did not show any effect. We demonstrated that some 5‐FUrd derivatives such as compound 5 are more effective than 5‐FU or 5‐FUrd concerning a cytotoxic (vs. cytostatic (5‐FU, 5‐FUrd)) effect on different cancer cell lines, but without cytotoxic side‐effects on differentiated macrophages. Thus, compound 5 is suggested as a novel potent cytotoxic multi‐anti‐cancer drug.  相似文献   
5.
A non‐radioactive method to determine 5‐Fluorouracil (5FU) incorporation into DNA has been developed. Isolated DNA was enzymatically degraded to bases and the resulting 5FU was measured with standard gas‐chromatography coupled to mass spectrometry (GC‐MS) and compared with that of radioactive 5FU in a cell line. Incorporation into DNA of the murine Colon 26‐B tumor treated with maximal tolerated doses of 5FU and fluorodeoxyuridine (FUdR) was maximal after 2 hour and was 15.4 and 71.0 fmol/µg DNA, respectively. After a plateau for about 3 days a decrease was observed to ± 2 fmol/µg DNA after 10 days. The assay is very sensitive and reproducible and can be used in a clinical setting.  相似文献   
6.
We used Xenopus embryo cells with a cell cycle of 20-30 min to detect inhibitory effects on cell proliferation. Inhibition of proliferation was observed when isolated embryonic cells were incubated for 16 h in a simple salt solution containing the well-known anticancer drugs 5-fluorouracil and adriamycin. In addition, three diterpene compounds isolated from the anticancer herbal medicine kansui: kansuinin B, 20-OD-ingenol Z, and 20-OD-ingenol E specifically inhibited the proliferation of isolated embryonic cells. The inhibitory compounds selected using the embryonic cells also inhibited proliferation of certain mammalian cell types.  相似文献   
7.
The action of 5‐Fluorouracil (5‐FU) is mediated by inhibition of thymidylate synthase (TS), which is regulated by cell cycle proteins controlled by protein phosphorylation. We studied the effects of staurosporine and its analogue UCN‐01, inhibitors of protein kinase C (PKC) on 5‐FU cytotoxicity in Lovo colon cancer cells. Each drug contributes equally to the cell cycle effects of the 5‐FU combinations. In sequential drug administration, the cell cycle distribution was determined by the first drug. Simultaneous 5‐FU combinations induced additive effects in induction of apoptosis. When staurosporine was used as the second drug, induction of apoptosis was 2‐fold higher than the sum of both drugs alone. Based on induction of apoptosis 5‐FU addition prior to the PKC inhibitors seemed preferable.  相似文献   
8.
5‐Fluorouracil (5FU) remains one of the most frequently prescribed chemotherapeutic drugs for the treatment of cancer. Recently, the pivotal role of the catabolic pathway of 5FU in the determination of toxicity towards 5FU has been highlighted. Patients with a (partial) dihydropyrimidine dehydrogenase deficiency proved to be at risk of developing severe toxicity after the administration of 5FU. A partial dihydropyrimidinase deficiency proved to be a novel pharmacogenetic disorder associated with severe 5FU toxicity.  相似文献   
9.
目的:研究选择性环氧化酶-2(COX-2)抑制剂塞来昔布联合氟尿嘧啶对胰腺癌细胞株SW1990生长的抑制作用,并对其机制进行初步探讨.方法:实验分为对照组、氟尿嘧啶组、塞来昔布组及两药联合组,将不同浓度的药物分剐作用于胰腺癌细胞株SW1990,MTT法检测各组细胞的生长抑制率,并探索产生最佳细胞生长抑制作用的药物浓度.流式细胞仪检测不同药物作用对肿瘤细胞周期的影响.RT-PCR检测各组细胞Survivin的表达情况.结果:MTT法显示氟尿嘧啶、塞来昔布均能抑制SW1990的生长,且细胞的存活率都随药物浓度的增加而降低.两药联合组对细胞生长的抑制作用更明显.流式细胞仪检测结果显示塞来昔布组、氟尿嘧啶组及两药联合组细胞较对照组G0/G1期细胞比例明显增加,S期和G2/M期细胞比例明显减少.RT-PCR结果显示氟尿嘧啶组、塞来昔布组、联合组都可下调Survivin的表达,以联合组最为明显.结论:塞来昔布联合氟尿嘧啶对胰腺癌SW1990细胞的生长具有抑制作用,其机制可能与下调Survivin的表达从而诱导细胞的凋亡和细胞周期的停滞有关.  相似文献   
10.
Two methods for measurement of thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) mRNA expression were compared. Although the relative mRNA levels compared to β‐actin measured with competitive template RT–PCR were different from the data obtained with a TaqMan based PCR, a significant correlation between the two assays was found.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号