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991.
Xu J  Yin Z  Gao W  Liu L  Wang R  Huang P  Yin Y  Liu P  Yu R  Shu Y 《Clinical lung cancer》2012,13(1):44-51
BackgroundNonsteroidal anti-inflammatory drugs (NSAIDs), especially aspirin, have emerged as the most potential chemopreventive agents. However, epidemiologic studies reported a controversial association between NSAID use and lung cancer risk. We conducted a meta-analysis to summarize the evidence for such relationship.MethodsEligible studies were identified by searching the electronic literature PubMed, Medline, Embase, and ScienceDirect databases for relevant reports and bibliographies. Studies were included if they designed as cohort study, case-control study, or clinical trial on the NSAID exposure and lung cancer with sufficient raw data to analyzes. Relative risk (RR) or odds ratio (OR) was used to evaluate the association between NSAIDs and lung cancer. Stratified analysis was also performed.ResultsA total of 19 studies including 20,266 lung cancer cases met the inclusion criteria. To the effect of aspirin on lung cancer, the combined RR for cohort studies was 0.96 (95%confidence interval [CI]: 0.78-1.19) and OR for case-control studies was 0.87 (95%CI: 0.69-1.09). When restricted in exposure of aspirin use to 7 tablets per week, the OR was 0.80 (95%CI: 0.67-0.95). The summary risk estimates showed no significant association between non-aspirin NSAID or overall NSAID use and lung cancer risk.ConclusionsAspirin use with a dose of 7 tablets per week can significantly reduce lung cancer risk, whereas non-aspirin NSAIDs showed no chemopreventive value. Greater attention should be paid to identifying appropriate individuals for this new indication of aspirin and the optimal dose and duration as a chemopreventive agent.  相似文献   
992.
目的 了解正常成人下腹壁厚度,并探讨其相关因素及其对根据指南针原理设计的排尿报警装置的意义。 方法 应用B超连续测量l00例成人的下腹壁及其浅层和深层的厚度,膀胱的前后径、上下径及左右径,并测量身高、体质量、测量点到脐部的距离,计算体质量指数(BMI)和膀胱容量,分析影响下腹壁厚度的相关因素。 结果 本组成人的下腹壁厚度(23.4±6.6)mm,95%可信区间为22.1~24.7 mm,与下腹壁深层厚度、浅层厚度和BMI、体质量、测量点到脐部的距离呈正相关(P<0.05),与膀胱容量、膀胱的上下径和左右径呈负相关(P<0.05),而与性别、身高、年龄、膀胱的前后径无相关性(P>0.05)。 结论 应用超声测量的成人下腹壁厚度为(23.4±6.6)mm,营养状态是最重要的影响因素,这为根据指南针原理设计的排尿报警装置的可行性提供了新的证据,对该装置的进一步研究具有重要的参考意义。  相似文献   
993.
目的?观察中医序贯疗法对溃疡性结肠炎维持缓解的疗效,比较其与美沙拉嗪在远期抗复发及不良反应等方面的差异,并探求UC复发的危险因素。方法?采用多中心随机对照方法观察204例活动期UC患者,经规范治疗后155例进入缓解期,继予中医序贯疗法或美沙拉嗪维持治疗。结果?随访半年,完成随访者共105例,中药组复发率为8.1%,美沙拉嗪组复发率为23.3%,2组相比有统计学差异(P<0.05)。结论?中医分期序贯治疗在UC维持缓解的远期疗效上具有显著优势。   相似文献   
994.
目的探讨抗原特异性免疫治疗对单核细胞及其来源的树突状细胞表达与免疫相关的重要表型的早期影响。方法 20名接受黄蜂毒液免疫治疗的患者,在治疗前(day0)和治疗后第1天(day1)、第3天(day3)和第5天(day5)抽取外周静脉血分离单核细胞(Mo),其中10名患者的单核细胞在体外培养6d诱导分化为单核细胞来源的树突状细胞(MoDC),流式细胞仪检测其表面ILT3,ILT4,B7H1,B7H2,MHCⅠ,MHCⅡ,CD80和CD86的表达。结果单核细胞和MoDC表面ILT3和ILT4表达显著增高,B7H1和CD86表达显著降低,与治疗前比较,差异有统计学意义(P<0.01)。未观察到B7H2,MHCⅠ,MHCⅡ和CD80的显著性改变(P>0.05)。结论单核细胞和MoDC表面的ILT3,ILT4,B7H1和CD86分子参与抗原特异性免疫治疗的早期耐受。  相似文献   
995.
996.
997.
RAD51 plays a key role in homologous recombination repair of double-stranded DNA breaks which may cause chromosomal breaks and genomic instability. We performed a meta-analysis of 9 epidemiological studies involving 13,241 cases and 13,203 controls that examined the association between RAD51 135G>C polymorphism and breast cancer. No significant association of RAD51 135G>C polymorphism with breast cancer was found in overall and European populations. However, after the studies which did not fulfill Hardy–Weinberg equilibrium were excluded, we observed an overall significant increased breast cancer risk (for the recessive model CC vs. GG/CG: OR = 1.35, 95% CI = 1.05–1.74, P heterogeneity = 0.06). In summary, our meta-analysis suggested the RAD51 135G>C polymorphism may contribute to breast cancer susceptibility.  相似文献   
998.
Interleukin-1β (IL-1β), which is involved in inflammatory and immunological responses, plays an important role in the development and progression of breast cancer. Three functional single nucleotide polymorphisms (SNPs) identified in IL-1β gene are thought to influence breast cancer risk. The results of the association between IL-1β polymorphisms and breast cancer remain inconsistent. Therefore, we conducted a meta-analysis of eight case–control studies with rs1143627 (T > C), rs16944 (C > T), and rs1143634 (C > T). We found that the variant CC genotype of rs1143627 was associated with a significantly increased breast cancer risk (CC vs. TT: OR = 1.37, 95% CI = 1.10–1.70, P = 0.22 for heterogeneity; the recessive model CC vs. TT/TC: OR = 1.40, 95% CI = 1.17–1.67, P = 0.49 for heterogeneity). For rs16944 (C > T) and rs1143634 (C > T), no significant associations were found in all genetic models. In conclusion, the present meta-analysis suggests that rs1143627 is associated with breast cancer risk.  相似文献   
999.
铂类药物对胃癌细胞生物学行为和MDR1表达的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
目的 研究顺铂(CDDP)和奥沙利铂(L-OHP)对人胃癌细胞株生长的抑制作用,进而分析两种铂类不同的作用机制。方法 用不同浓度(IC10、IC30、IC50)的CDDP和L-OHP分别作用胃癌细胞株(BGC-823和SGC-7901)24、48、72h,应用MTT比色法检测细胞的增殖抑制率;采用RT-PCR法检测MDR1基因表达量。IC30浓度的两种铂类药物作用于胃癌细胞48h后,用流式细胞术分析细胞凋亡,细胞划痕实验评价细胞迁移能力。结果 两种铂类药物作用后,胃癌细胞BGC-823和SGC-7901的增殖受到抑制,呈时间和剂量依赖,L-OHP的量效变化更明显。两种铂类药物作用后,MDR1呈上升趋势,随着浓度增加和(或)时间的延长,表达增强。BGC-823细胞的凋亡率增加较SGC-7901细胞明显,L-OHP组的细胞凋亡率高于CDDP组;BGC-823细胞的增殖迁移较SGC-7901细胞慢而距离短,CDDP作用后细胞的增殖迁移较L-OHP作用后快而距离长。结论 L-OHP诱导胃癌细胞凋亡及抑制细胞迁移侵袭的能力均强于CDDP。胃癌对两种铂类药的耐药机制可能与其诱导MDR1表达上调有关。  相似文献   
1000.
Breast cancer is the most prevalent cancer worldwide. Many published articles have evaluated the association between the transforming growth factor beta 1 (TGFB1) T29C polymorphism and breast cancer risk. However, the results remain inconclusive. In order to derive a more precise estimation of the association, a meta-analysis was performed in this study. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the association. A total of 12 studies including 10,417 breast cancer cases and 11,455 controls were identified. Overall, no significant associations between the TGFB1 T29C polymorphism and breast cancer risk were found for CC versus TT (OR = 1.00, 95% CI = 0.92–1.09), TC versus TT (OR = 0.98, 95% CI = 0.93–1.05), CC/TC versus TT (OR = 0.99, 95% CI = 0.93–1.05), and CC versus TC/TT (OR = 1.00, 95% CI = 0.93–1.08). In the subgroup analysis by ethnicity, source of controls, and menopausal status, there was still no significant association detected in all genetic models. In conclusion, the present meta-analysis suggests that the TGFB1 T29C polymorphism is not a low-penetrant risk factor for developing breast cancer.  相似文献   
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