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921.
长白落叶松激素含量与生长的关系及在早期选择中的应用   总被引:1,自引:2,他引:1  
冯玉龙  王丽华 《植物研究》1998,18(4):461-467
用间接酶联免疫吸附法测定了不同季节不同种源长白落叶松激素含量。结果表明:不同季节长白落叶松的激素含量不同,速生期长白落叶松赤霉素、生长素和细胞分裂素含量高,脱落酸含量低,赤霉素/脱落酸比值大,生长缓慢期测定结果恰好相反。各类激素含量在不同种源长白落叶松间的变异显著,且与生长性状的差异密切相关。生长快的种源赤霉素,细胞分裂素含量高,脱落酸含量低,赤霉素/脱落酸之比大。生长慢的种源则相反。回归分析表明  相似文献   
922.
徐菱蔓  梁素英  黄远德  刘斌  郑洁 《生物磁学》2013,(36):7066-7068
目的:探讨FOLFOX方案联合西妥昔单抗治疗转移性结直肠癌的近期临床疗效及安全性。方法:选择2009年2月~2011年2月本院诊治的42例转移性结直肠癌患者为研究对象,采用随机数字表法将其随机分入对照组与观察组,其中对照组20例,观察组22例。对照组患者接受FOLFOX方案治疗,每2周重复1次,治疗3周期;观察组患者给予FOLFOX方案联合西妥昔单抗治疗。比较两组的近期疗效及毒副反应。结果:观察组的客观缓解率和疾病控制率均显著高于对照组,差别具有统计学意义(P〈0.05);骨髓抑制、消化道反应、神经毒性是两组常见的毒副反应,两组患者骨髓抑制、消化道反应、神经毒性、脱发及肝功能损害发生率无显著差别(P〉0.05),观察组痤疮样皮疹的发生率显著高于对照组(36.4%VS0,P〈0.05)。结论:西妥昔单抗联合FOLFOX方案可提高转移性结直肠癌患者的近期疗效,毒副反应可耐受。  相似文献   
923.
目的评估IL-17Frs763780多态性与癌易感性的关联。方法通过检索Pubmed、Embase、OV-ID、CBM、WanfangData和CNKI,筛选出发表至2013年10月与IL-17基因多态性和癌易感性有关的病例对照研究。采用比值比(ORs)和95%可信区间(95%CIs)评价关联强度。结果最终纳入5篇病例对照研究,包括1407例肿瘤患者和2164例健康对照。然而,分析后发现IL-17Frs763780多态性和癌无统计学意义的关联(TT+TC vs CC:OR=0.85,95%CI=0.46~1.57,P=0.60;TTVSTC+CC:OR=1.00,95%CI=0.76-1.33,P=0.99;TC vs CC:OR=0.83,95%CI=0.44—1.55,P=0.55;TT vs CC:OR=0.85,95%CI=0.46-1.59,P=0.62)。按肿瘤类型亚组分析提示在胃癌和其他肿瘤存在相似的结果。结论IL-17Frs763780多态性可能并不增加肿瘤的易感性。  相似文献   
924.
Esophageal cancer is common in China. There is a lack of treatment strategies for metastatic esophageal cancer (MEC) after radical surgery on the primary tumor. Cryoablation is an attractive option because tumor necrosis can be safely induced in a minimally invasive manner. This study assessed its therapeutic effect in MEC after failure of radical surgery. One hundred and forty patients met the inclusion criteria from May, 2003 to March, 2011. Comprehensive cryotherapy of multiple metastases was performed on 105 patients; 35 received chemotherapy. No severe complications occurred during or after cryoablation. Overall survival (OS) was assessed according to therapeutic protocol, pathologic type, treatment timing and number of procedures. The OS of patients who received comprehensive cryoablation (44 ± 20 months) was significantly longer than that of those who underwent chemotherapy (23 ± 24 months; P = 0.0006). In the cryotherapy group, the OS for squamous cell carcinoma (45 ± 19 months) was longer than that for adenocarcinoma (33 ± 18 months; P = 0.0435); the OS for timely cryoablation (46 ± 19 months) was longer than that for delayed cryoablation (33 ± 20 months; P = 0.0193); the OS for multiple cryoablation (50 ± 17 months) was longer than that for single cryoablation (37 ± 20 months; P = 0.0172); and the OS for cryo-immunotherapy (56 ± 17 months) was longer than that for cryoablation alone (39 ± 19 months; P = 0.0011). Thus, comprehensive cryotherapy may have advantages over chemotherapy in the treatment of MEC and, in patients with squamous cell carcinoma, supplementary immunotherapy and timely and multiple cryoablation may be associated with a better prognosis.  相似文献   
925.
Migration-stimulating factor (MSF), an oncofetal truncated isoform of fibronectin, is a potent stimulator of cell invasion. However, its distribution and motogenic role in non-small cell lung cancer (NSCLC) have never been identified. In this study, real-time PCR and immunohistochemical staining (IHC) were performed to detect MSF mRNA and protein levels in tumor tissues and matched adjacent tumor-free tissues. Furthermore, to examine the effect of MSF on invasiveness, MSF was upregulated in A549 cells. The invasiveness and viability of A549 cells were then determined using a transwell migration assay and the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assays, respectively. The expression level of MSF in NSCLC tissue was markedly higher than in matched adjacent tumor-free tissue. Additionally, the level of MSF protein expression in stage III and IV NSCLC samples was higher than in stage I and II NSCLC samples. More importantly, we also demonstrated that migration and invasion of A549 cells increased substantially after upregulating MSF, although proliferation remained unchanged. Meanwhile, we found no correlation between increasing motility and invasiveness of MSF-overexpressing cells and expression levels and activities of matrix metalloprotease MMP-2 and MMP-9. Our current study shows that MSF plays a role in migration and invasion of A549 cells and suggests that MSF may be a potential biomarker of NSCLC progression.  相似文献   
926.
目的:探讨中国北方地区血清钙、维生素D水平与乳腺癌及相关临床因素的关系.方法:选取2007年12月至2012年7月哈尔滨医科大学附属肿瘤医院794例女性乳腺癌患者及976例乳腺良性肿瘤患者,并以128例健康妇女为对照,取空腹血清采用原子吸收分光光度法检测三组血清钙含量,采用放免法检测三组中162例血清25(OH)D含量,结合相关临床资料进行分析.结果:乳腺癌组血清钙含量为2.26± 0.12 mmol/L,乳腺良性肿瘤组血清钙含量为2.26±0.09 mmol/L,正常对照组血清钙含量为2.25±0.24 mmol/L,经方差分析,三组总体均数差别无统计学意义(P>0.05);乳腺癌患者的血清钙水平与年龄、TNM分期、BMI、绝经情况、乳腺癌家族遗传史无关(P>0.05).乳腺癌组血清25(OH)D含量为41.91±7.55 ng/mL,乳腺良性肿瘤血清25(OH)D含量为54.62±7.48 ng/mL,正常对照组血清25(OH)D含量为56.15±8.87 ng/mL,经方差分析,乳腺癌患者血清25(OH)D含量低于乳腺良性肿瘤组,差别有统计学意义(P<0.05),乳腺良性肿瘤组与正常对照组差别无统计学意义(P>0.05);乳腺癌患者的维生素D水平与年龄、TNM分期、BMI、绝经情况有关(P<0.05),而与乳腺癌家族遗传史无关(P>0.05).结论:中国北方地区的乳腺癌患者血清钙水平与乳腺良性肿瘤患者无明显差异.乳腺癌患者的维生素D水平低于乳腺良性肿瘤患者,并且与年龄、TNM分期、BMI、绝经情况有关.维生素D水平降低可能与乳腺癌的发生有关,高水平的维生素D可能会降低女性患乳癌的风险.  相似文献   
927.
2021年诺贝尔生理学或医学奖由戴维·朱利叶斯(David Julius)和阿德姆?帕塔普蒂安(Ardem Patapoutian)共同获得,以表彰二人分别在温度感受器辣椒素受体(TRPV1)和触觉感受器PIEZO1/2方面做出的杰出贡献.此项工作有助于阐明神经系统如何感知冷、热和机械刺激的机制,以及开发治疗疼痛的药物...  相似文献   
928.
The p14ARF protein is a well‐known regulator of p53‐dependent and p53‐independent tumor‐suppressive activities. In unstressed cells, p14ARF is predominantly sequestered in the nucleoli, bound to its nucleolar interaction partner NPM. Upon genotoxic stress, p14ARF undergoes an immediate redistribution to the nucleo‐ and cytoplasm, where it promotes activation of cell cycle arrest and apoptosis. Here, we identify p14ARF as a novel interaction partner and substrate of PRMT1 (protein arginine methyltransferase 1). PRMT1 methylates several arginine residues in the C‐terminal nuclear/nucleolar localization sequence (NLS/NoLS) of p14ARF. In the absence of cellular stress, these arginines are crucial for nucleolar localization of p14ARF. Genotoxic stress causes augmented interaction between PRMT1 and p14ARF, accompanied by arginine methylation of p14ARF. PRMT1‐dependent NLS/NoLS methylation promotes the release of p14ARF from NPM and nucleolar sequestration, subsequently leading to p53‐independent apoptosis. This PRMT1‐p14ARF cooperation is cancer‐relevant and indicative for PDAC (pancreatic ductal adenocarcinoma) prognosis and chemotherapy response of pancreatic tumor cells. Our data reveal that PRMT1‐mediated arginine methylation is an important trigger for p14ARF’s stress‐induced tumor‐suppressive function.  相似文献   
929.
The present study evaluated the anticancer potential of celastrol through down-regulation of matrix metalloproteinase-2 (MMP-2) and MMP-9. HeLa cells were incubated with different concentrations of celastrol (1, 10 and 100 µM) for 48h. Doxorubicin was used as a reference drug. Cancer cell migration, apoptosis, cell viability and mitochondrial fragmentation were evaluated following celastrol treatment. In addition, the expression level of MMP-2, MMP-9 and caspase-3 was evaluated following celastrol treatment. HeLa cell viability was 94.1 ± 7, 53.4 ± 4 and 36.3 ± 2% at 1-100 µM of celastrol, respectively. Apoptotic cell numbers were increased, and inhibition of larger wounds in cancer cells was observed following celastrol treatment. Celastrol-treated cells showed condensed nuclei and clumped mitochondria. Reduced expression of MMP-2 and MMP-9 and increased expression of caspase-3 were observed following celastrol treatment. Based on the experimental results, we are concluding that the celastrol was effective against HeLa cervical cancer cells.  相似文献   
930.
Our previous studies have shown that the Adipose-derived mesenchymal stem cells (ADSCs) can regulate metastasis and development of ovarian cancer. However, its specific mechanism has yet to be fully revealed. In this study, an RNA-seq approach was adopted to compare the differences in mRNA levels in ovarian cancer cells being given or not given ADSCs. The mRNA level of paired box 8 (PAX8) changed significantly and was confirmed as an important factor in tumour-inducing effect of ADSCs. In comparison with the ovarian cancer cells cultured in the common growth medium, those cultured in the medium supplemented with ADSCs showed a significant increase of the PAX8 level. Moreover, the cancer cell growth could be restricted, even in the ADSC-treated group (P < .05), by inhibiting PAX8. In addition, an overexpression of PAX8 could elevate the proliferation of ovarian cancer cells. Moreover, Co-IP assays in ovarian cancer cells revealed that an interaction existed between endogenous PAX8 and TAZ. And the PAX8 levels regulated the degradation of TAZ. The bioluminescence images captured in vivo manifested that the proliferation and the PAX8 expression level in ovarian cancers increased in the ADMSC-treated group, and the effect of ADSCs in promoting tumours was weakened through inhibiting PAX8. Our findings indicate that the PAX8 expression increment could contribute a role in promoting the ADSC-induced ovarian cancer cell proliferation through TAZ stability regulation.  相似文献   
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