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111.
在苗期应用自然诱发鉴定法对海南普通野生稻(Oryza rufipogonGriff.)41个居群的410份材料进行了2年的稻瘟病(rice blast)抗性鉴定,结果表明:经过初鉴和复鉴,410份海南普通野生稻中有21份表现高抗,占5.1%,117份表现抗,占28.5%,说明海南普通野生稻具有较好的稻瘟病抗性。  相似文献   
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High-throughout single nucleotide polymorphism detection technology and the existing knowledge provide strong support for mining the disease-related haplotypes and genes. In this study, first, we apply four kinds of haplotype identification methods (Confidence Intervals, Four Gamete Tests, Solid Spine of LD and fusing method of haplotype block) into high-throughout SNP genotype data to identify blocks, then use cluster analysis to verify the effectiveness of the four methods, and select the alcoholism-related SNP haplotypes through risk analysis. Second, we establish a mapping from haplotypes to alcoholism-related genes. Third, we inquire NCBI SNP and gene databases to locate the blocks and identify the candidate genes. In the end, we make gene function annotation by KEGG, Biocarta, and GO database. We find 159 haplotype blocks, which relate to the alcoholism most possibly on chromosome 1∼22, including 227 haplotypes, of which 102 SNP haplotypes may increase the risk of alcoholism. We get 121 alcoholism-related genes and verify their reliability by the functional annotation of biology. In a word, we not only can handle the SNP data easily, but also can locate the disease-related genes precisely by combining our novel strategies of mining alcoholism-related haplotypes and genes with existing knowledge framework. Supported by the National Natural Science Foundation of China (Grant Nos. 30570424, 60601010 and 30600367), the National High-Tech Research and Development Program of China, (Grant No.2007AA02Z329), the Key Science and Technology Program of Heilongjiang Province(Grant No.GB03C602-4), Natural Science Foundation of Heilongjiang Province (Grant No. F2008-02), Youth Science Foundation of Harbin Medical University (Grant No. 060045) and Science Foundation of Heilongjiang Province Education Department (Grant Nos. 11531113 and 1152hq28).  相似文献   
115.

Background

Gastrointestinal neuroendocrine neoplasms (GI-NENs) are often located in the deep mucosa or submucosa, and the efficacy of endoscopic biopsy for diagnosis and treatment of GI-NENs is not fully understood.

Objective

The current study analyzed GI-NENs, especially those diagnosed pathologically and resected endoscopically, and focused on the biopsy and cold biopsy forceps polypectomy (CBP) to analyze their roles in diagnosing and treating GI-NENs.

Methods

Clinical data of all GI-NENs were reviewed from January 2006 to March 2012. Histopathology was used to diagnose GI-NENs, which were confirmed by immunohistochemistry.

Results

67.96% GI-NENs were diagnosed pathologically by endoscopy. Only 26.21% were diagnosed pathologically by biopsies before treatment. The diagnostic rate was significantly higher in polypoid (76.47%) and submucosal lesions (68.75%), than in ulcerative lesions (12.00%). However, biopsies were only taken in 56.31% patients, including 51.52% of polypoid lesions, 35.56% of submucosal lesions and 100.00% of ulcerative lesions. Endoscopic resection removed 61.76% of GI-NENs, including six by CBP, 14 by snare polypectomy with electrocauterization, 28 by endoscopic mucosal resection (EMR) and 15 by endoscopic submucosal dissection (ESD). 51.52% polypoid GI-NENs had infiltrated the submucosa under microscopic examination. CBP had a significantly higher rate of remnant (33.33%) than snare polypectomy with electrocauterization, EMR and ESD (all 0.00%).

Conclusions

Biopsies for all polypoid and submucosal lesions will improve pre-operative diagnosis. The high rate of submucosal infiltration of polypoid GI-NENs determined that CBP was inadequate in the treatment of GI-NENs. Diminutive polypoid GI-NENs that disappeared after CBP had a high risk of remnant and should be closely followed up over the long term.  相似文献   
116.
种群生活史特征和空间分布格局对于分析种群演替动态规律、判定种群分布规律和预测种群演化过程及变化趋势均具有重要的理论和现实意义.本文从静态生命表、年龄结构、存活曲线三个方面分析了东灵山地区辽东栎种群的生活史特征.结果表明:物种生物学因素是影响辽东栎种群生存力最主要因素,辽东栎种群静态生命表中生命期望值逐渐降低反映出种群生存力下降的趋势.空间分布格局分析表明辽东栎种群各个径级的个体都属于聚集分布.辽东栎实生苗和萌生苗共存是辽东栎种群适应环境压力和与环境协同进化的结果,表明自然状态下辽东栎种群具有较高的稳定性.由于辽东栎种群的这种较强的稳定性和适应能力,随着辽东栎种群发育整个群落将趋于进展演替,最终形成稳定和充分利用环境资源的顶极群落结构.  相似文献   
117.
Although many previous reports have examined the function of prostaglandin E2 (PGE2) in the migration and proliferation of various cell types, the role of the actin cytoskeleton in human mesenchymal stem cells (hMSCs) migration and proliferation has not been reported. The present study examined the involvement of profilin‐1 (Pfn‐1) and filamentous‐actin (F‐actin) in PGE2‐induced hMSC migration and proliferation and its related signal pathways. PGE2 (10?6 M) increased both cell migration and proliferation, and also increased E‐type prostaglandin receptor 2 (EP2) mRNA expression, β‐arrestin‐1 phosphorylation, and c‐Jun N‐terminal kinase (JNK) phosphorylation. Small interfering RNA (siRNA)‐mediated knockdown of β‐arrestin‐1 and JNK (‐1, ‐2, ‐3) inhibited PGE2‐induced growth of hMSCs. PGE2 also activated Pfn‐1, which was blocked by JNK siRNA, and induced F‐actin level and organization. Downregulation of Pfn‐1 by siRNA decreased the level and organization of F‐actin. In addition, specific siRNA for TRIO and F‐actin‐binding protein (TRIOBP) reduced the PGE2‐induced increase in hMSC migration and proliferation. Together, these experimental data demonstrate that PGE2 partially stimulates hMSCs migration and proliferation by interaction of Pfn‐1 and F‐actin via EP2 receptor‐dependent β‐arrestin‐1/JNK signaling pathways. J. Cell. Physiol. 226: 559–571, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
118.
Skeletal muscle lipid accumulation is associated with several chronic metabolic disorders, including obesity, insulin resistance (IR) and type 2 diabetes. The aim of this study is to evaluate whether static imaging time-of-flight-secondary-ion mass spectrometry (TOF-SIMS) equipped with a Bismuth-cluster ion source can be used for studying skeletal muscle lipid accumulation associated with obesity. Mouse gastrocnemius muscle tissues in 10-week-old obese ob/ob (n = 8) and lean wild-type C57/BL6 (n = 6) mice were analyzed by TOF-SIMS. Our results showed that signal intensities of fatty acids (FAs) and diacylglycerols (DAGs) were significantly increased in skeletal muscle of the obese ob/ob mice as compared to the lean wild-type mice. These differences were revealed through a global analytical approach, principal component analysis (PCA) of TOF-SIMS spectra, and ion-specific TOF-SIMS images. Region-of-interest (ROI) analysis showed that FA signal intensities within the muscle cell were significantly increased in ob/ob mice. Moreover, analysis of the ratio between different FA peaks revealed changes in monounsaturated FAs (MUFAs) and polyunsaturated FAs (PUFAs), which is in agreement with previous reports on obesity. These changes in FA composition were also reflected in the ratio of different DAGs or phosphatidylcholines (PCs) that contain different FA residues. Imaging TOF-SIMS together with PCA of TOF-SIMS spectra is a promising tool for studying skeletal muscle lipid accumulation associated with obesity.  相似文献   
119.
利用深层发酵培养基对两种食药用菌(香菇、猴头菌)进行深层发酵培养,然后分别将香菇(猴头菌)发酵滤液、奶粉、无菌水按不同比例配制成相应的复原奶,并接种乳酸菌制成酸乳。同时检测不同比例发酵滤液添加量所制得的酸乳的营养和理化特性,选择出了最佳比例的滤液添加量,即香菇滤液添加量以3份较好,而猴头菌则以4份滤液添加量最佳。  相似文献   
120.
Jang HH  Lee KO  Chi YH  Jung BG  Park SK  Park JH  Lee JR  Lee SS  Moon JC  Yun JW  Choi YO  Kim WY  Kang JS  Cheong GW  Yun DJ  Rhee SG  Cho MJ  Lee SY 《Cell》2004,117(5):625-635
Although a great deal is known biochemically about peroxiredoxins (Prxs), little is known about their real physiological function. We show here that two cytosolic yeast Prxs, cPrxI and II, which display diversity in structure and apparent molecular weights (MW), can act alternatively as peroxidases and molecular chaperones. The peroxidase function predominates in the lower MW forms, whereas the chaperone function predominates in the higher MW complexes. Oxidative stress and heat shock exposure of yeasts causes the protein structures of cPrxI and II to shift from low MW species to high MW complexes. This triggers a peroxidase-to-chaperone functional switch. These in vivo changes are primarily guided by the active peroxidase site residue, Cys(47), which serves as an efficient "H(2)O(2)-sensor" in the cells. The chaperone function of these proteins enhances yeast resistance to heat shock.  相似文献   
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