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AIM: To investigate the expression and clinical significance of PAK4 in the cell lines and tissues of non-small cell lung cancer (NSCLC). METHODS: PAK4 expression in human bronchial epithelial (HBE) cells, NSCLC cell lines, NSCLC tissues and adjacent non-tumor tissues were assessed by immunohistochemistry, real-time PCR and Western blot. Prognostic value of PAK4 expression was evaluated by Kaplan-Meier analysis and Cox regression. RESULTS: PAK4 was over-expressed in the NSCLC cell lines at both mRNA and protein levels compared with HBE cells (P<0.05). PAK4 was over-expressed in the NSCLC tissues at both mRNA and protein levels compared with adjacent non-tumor tissues (P<0.05). PAK4 was over-expressed in the metastatic NSCLC tissues compared with the primary NSCLC tissues (P<0.05). Higher PAK4 staining scores were positively correlated with differentiation, lymph node metastasis, distant metastasis, and clinical stage. Kaplan-Meier analysis and log-rank test showed that overall survival was significantly different between the patients with up-regulated PAK4 and the patients with down-regulated PAK4(P<0.05). PAK4 over-expression was associated with NSCLC progression.CONCLUSION: Increased PAK4 expression was associated with tumor invasion, metastasis and prognosis in the patients with NSCLC. PAK4 is an important prognostic marker and potential therapeutic target in NSCLC. 相似文献
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AIM: To explore the relationship and molecular mechanism between microRNA-21(miR-21) and Schwann cells (SC) following peripheral nerve injury. METHODS: The mRNA expression of miR-21 and phosphatase and tensin homologue deleted on chromosome ten (PTEN) in animal model were detected by real-time PCR. The over-expression of miR-21 and inhibition of miR-21 expression in the Schwann cells according to transfection of lentiviral vectors were performed, the nonspecific miRNA was used as a negative control (NC). The cell apoptosis was measured by flow cytometry. The mRNA expression of miR-21 and PTEN in the cells was detected by real-time PCR. The protein expression of PTEN and cleaved caspase-3 was determined by Western blot. RESULTS: The level of miR-21 was significantly higher and the mRNA level of PTEN was significantly lower in the model of nerve injury than those in control group. miR-21 over-expression decreased the number of apoptotic Schwann cells compared with NC-SC. The mRNA expression of PTEN was down-regulated by over-expression of miR-21. The protein expression of PTEN and cleaved caspase-3 was down-regulated by over-expression of miR-21(P<0.05). CONCLUSION: miR-21 may play an important role in the peripheral nerve injury through inhibiting apoptosis of Schwann cells by down-regulating the expression of PTEN. 相似文献
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Jerzy Drzewiecki 《Euphytica》2001,119(3):279-287
Wheat-rye translocation line (2BS/2RL) has been developed for resistance to biotype L of Hessian fly and agronomically useful
traits. AFLP analysis using 64 primer pairs was conducted in order to identify 2RL-specific polymorphisms between “Coker 797”
(non-2RL), near-isogenic line (NIL) carrying 2RL, and “Hamlet”. Nine primer combinations identified twelve reproducible polymorphic
fragments in the NIL carrying 2RL. These twelve fragments were cloned and sequenced with an aim towards converting AFLP markers
into sequence tagged sites (STS). A comparison of the 12 sequences with non-redundant accessions in the NCBI database using
the BLAST search option indicated that one fragment of approximately 200 bp in length (amplified using primer combination
E+AAC / M+CTA) was highly homologous with the rye-specific repetitive sequence R173-1 and Wis-2-lA, a retrotransposon-like
element in wheat. Two STS primers (SJ07 and SJ09) out of twelve STS primer sets enabled the detection of polymorphisms between
Coker 797 and NIL carrying 2RL. In order to verify whether the polymorphism detected by primers SJ07 and SJ09 was in fact
the result of the presence of 2RL, additional plant material was examined. Amplified products of about 260 bp fragment with
the SJ07 primer set were generated in rye cvs.“Chilbohomil” and “Jochunhomil”, triticale experimental line Suwon 15, and wheat
experimental line K-14 (1AL/1RS & 2BS/2RL), as well as NIL carrying 2RL and Hamlet, but not in Coker 797 (non-2RL), “Keumgangmil”
(non-translocation wheat), KS92WGRC17 (PI592729 /;/ 6BS/6BL-6RL), KS92WGRC19 (P1592731 /;/ 4BS/4BL-6RL), “TAM200” (1AL/1RS),
and “Siouxland” (1BL/1RS). Our data suggest that primer set SJ07 amplifies a “2RL-specific” fragment of diagnostic value.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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以转Xa 21基因的水稻优良恢复系BR527为抗白叶枯病基因供体,分别与不育系金23A、G46A、D62A、D200A进行组配,研究该基因在改良杂交水稻白叶枯病抗性方面的作用。分子检测表明,供体基因能够稳定遗传给杂交组合;田间接种鉴定发现杂交组合对P1,P2,P3,P4,P6和CII,CIV,CV等白叶枯病菌生理小种均表现出抗或高抗,揭示Xa 21基因的抗性好,抗谱广;农艺性状考察结果显示这些杂交组合的农艺性状与对照组合比较没有明显改变。说明该基因可以作为一个显性抗白叶枯病基因在杂交水稻抗性改良上上加以应用,与此同时,得到了四个白叶枯病抗性改良的优良杂交水稻组合。 相似文献
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[目的]研究新鲜和盐渍F21金针菇主要成分的含量。[方法]选取F21金针菇的新鲜和盐渍品,用凯氏定氮法、索氏脂肪提取法等方法对其蛋白质、脂肪、多糖和磷元素进行了测定。[结果]F21金针菇新鲜干品和盐渍品的蛋白质的含量分别为21.63%、15.04%,脂肪含量分别为4.70%、7.94%,多糖含量分别为33.70%、45.28%,总磷含量分别为0.2837%、0.1591%。F21金针菇新鲜干品的蛋白质和磷元素含量均高于其盐渍品,分别高出30.46%、43.91%,而脂肪和多糖的含量则低于其盐渍品,分别减少68.93%、34.36%。[结论]盐渍金针菇是金针菇生产加工的有效途径。 相似文献
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分子标记选择小麦抗白粉病基因Pm4b、Pm13和Pm21聚合体 总被引:43,自引:2,他引:43
培育多个抗病基因聚合的小麦品种是提高其抗病广谱性和持久性的有效途径之一。利用小麦抗白粉病基因Pm4、Pm13、Pm2 1的特异PCR标记 ,对含有Pm4b、Pm13、Pm2 1的小麦品系复合杂交F2 代 4 0个植株进行检测 ,从中选择到Pm4b +Pm13+Pm2 13个基因聚合的抗病植株 11个 ,检测、选择到Pm4b +Pm13、Pm4b +Pm2 1、Pm13+Pm2 12个基因聚合的抗病植株 19个 ,为持久、广谱抗病小麦育种奠定了基础。研究还表明 ,3个独立的显性抗病基因在F2 代分离群体中的分离比例基本符合孟德尔独立分配定律 ,在小麦背景下的遗传稳定性 ,与该基因供体和普通小麦的亲缘关系密切相关 ,亲缘关系越远 ,丢失的概率越大。因此 ,在育种过程中对外源基因鉴定和跟踪非常必要 相似文献