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遗传规划中的基因内区研究 被引量:1
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作者 云庆夏 卢少华 《控制与决策》 EI CSCD 北大核心 2002年第6期940-943,共4页
利用试验证实遗传规划的个体中存在基因内区。它们是冗余的表达式 ,附加在算法树上 ,使个体变得臃肿 ,但对实际的输出结果没有影响。它对进化的收敛既有积极作用 ,也有消极作用。通过对遗传操作方法和参数的研究 ,揭示出基因内区发生的... 利用试验证实遗传规划的个体中存在基因内区。它们是冗余的表达式 ,附加在算法树上 ,使个体变得臃肿 ,但对实际的输出结果没有影响。它对进化的收敛既有积极作用 ,也有消极作用。通过对遗传操作方法和参数的研究 ,揭示出基因内区发生的规律 ,并提出扬长避短的途径。 展开更多
关键词 遗传规则 基因内区 遗传算法 罚函数 计算机
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影响遗传规划基因内区的因素分析 被引量:3
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作者 卢少华 云庆夏 夏安邦 《系统工程理论与实践》 EI CSCD 北大核心 2003年第2期101-105,共5页
通过众多的试验和分析 ,证实遗传规划的个体中存在基因内区 ,它对进化的收敛既有积极作用也有消极作用 .文中通过对有关遗传操作方法和参数的研究 ,定性地分析了它们对基因内区的影响 ,并指出抑制基因内区消极作用的途径 .
关键词 遗传规划 基因内区 消极作用 进化过程 积极作用
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内嵌基因表达式编程及其在函数发现中的应用 被引量:6
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作者 向勇 唐常杰 +2 位作者 朱明放 陈瑜 代术成 《电子科技大学学报》 EI CAS CSCD 北大核心 2011年第1期116-121,共6页
为了提高表达效率,提出了新的基因解码方案,形成了内嵌基因表达式编程算法EGEP;提出了极大表达树、嵌套表达树和拼接表达树等概念;分析了基因的表达空间和算法的复杂度。实验表明,该算法提高了函数发现的成功率;在小规模种群的函数中其... 为了提高表达效率,提出了新的基因解码方案,形成了内嵌基因表达式编程算法EGEP;提出了极大表达树、嵌套表达树和拼接表达树等概念;分析了基因的表达空间和算法的复杂度。实验表明,该算法提高了函数发现的成功率;在小规模种群的函数中其能力明显优于GEP。在单基因情况下,目标为一元函数和二元函数时,EGEP平均成功辈数分别为GEP算法的25.5%和16.3%;各种规模下,在EGEP算法中二元函数的成功率平均比GEP提高43%以上。 展开更多
关键词 函数发现 遗传算法 基因表达式编程 基因内区
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连续编码的基因表达式编程算法 被引量:4
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作者 曹维 林毅申 《计算机工程与设计》 北大核心 2017年第3期682-686,734,共6页
提出一种基因连续编码的改进GEP算法。通过改造K表达式的编码规则消灭基因内区,使用更短的编码规则,尽可能利用到每位编码,保持基因多样性,改善其跳出局部最优的能力。由于充分利用基因连续编码的天然基因片断特性,不须定义多基因结构,... 提出一种基因连续编码的改进GEP算法。通过改造K表达式的编码规则消灭基因内区,使用更短的编码规则,尽可能利用到每位编码,保持基因多样性,改善其跳出局部最优的能力。由于充分利用基因连续编码的天然基因片断特性,不须定义多基因结构,降低算法设置的遗传算子数量,减少人工参数设置对算法的干扰。在序列推理和函数发现数据集上的实验结果表明,该算法具有更快的运算速度、较高的精度和较强的寻优能力。 展开更多
关键词 基因表达式编程 基因内区 函数发现 进化计算 遗传算法
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基于内嵌基因表达式编程的函数优化
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作者 向勇 唐常杰 +1 位作者 曾涛 张敏 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2010年第4期91-96,共6页
基因表达式编程(GEP)算法在解码时常存在未表达的基因内区,在解决函数优化问题时存在缺陷,使得对简单函数的优化性能不如遗传算法(GA),而对复杂函数优化收敛速度较慢。为了改善基因表达效率和提高优化性能,做了下列工作:提出了新的基因... 基因表达式编程(GEP)算法在解码时常存在未表达的基因内区,在解决函数优化问题时存在缺陷,使得对简单函数的优化性能不如遗传算法(GA),而对复杂函数优化收敛速度较慢。为了改善基因表达效率和提高优化性能,做了下列工作:提出了新的基因解码方法,形成了内嵌基因表达式编程算法EGEP;设计了适合优化问题的个体编码方案;分析了个体的表达空间。实验表明,EGEP对简单函数优化的性能优于传统遗传算法;EGEP提高了对复杂函数的优化能力,即使在运行辈数降低200倍时,得到的性能仍然优于传统GEP和遗传算法。 展开更多
关键词 函数优化 遗传算法 基因表达式编程 基因内区
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Relationship Between the First Base of the Donor Splice Site of Waxy Gene Intron 1 and Amylose Content in Yunnan Indigenous Rice Varieties 被引量:2
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作者 ZHANG Ya 1i Xu Ming hui +2 位作者 ZENG Ya wen YAO Chun xin CHEN Shan na 《Rice science》 SCIE 2007年第3期189-194,共6页
There exists a single nucleotide polymorphism, G or T, at the first base of the donor splice site of waxy gene intron 1 in rice. In order to study the relationship between the first base of the donor splice site of wa... There exists a single nucleotide polymorphism, G or T, at the first base of the donor splice site of waxy gene intron 1 in rice. In order to study the relationship between the first base of the donor splice site of waxy gene intron 1 and amylose content in rice, the one-step PCR method was used to determine whether it is G or T in 220 Yunnan indigenous rice varieties from 14 districts, 55 towns/counties of Yunnan Province, and 101 varieties of which were validated by the PCR-Acc I method. According to the G/T polymorphism, 164 rice varieties showed GG-genotype, while the other 56 fell into TT-genotype, accounting for 74.5% and 25.5% of all the test varieties, respectively. When all the rice varieties were divided into indica and japonica subspecies, it was found that 80.5% of indica rice and 67.0% of japonica rice belonged to GG-genotype. The rice varieties with GG-genotype had significantly higher amylose content (18.95% on average) than those with TT-genotype (all below 16%), but 33 rice varieties with GG-genotype still had low amylose content ranging from 3.91% to 15.93%, and most of them came from the Dai minority area in the Southwest of Yunnan Province. However, there was no significant difference in the mean amylose content of the same GG or TT genotypes between indica and japonica rice, suggesting that different genetic backgrounds, indica or japonica, had no effect on amylose content. The coefficient of correlation between the genotype and amylose content was 0.733 (P<0.01). 展开更多
关键词 云南 水稻 基因内区 遗传多样性 基因
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Increment of hFIX expression with endogenous intron 1 in vitro
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作者 ZHENG BING XIAO YUN QIU +4 位作者 MIN TAN YONG NA XING DARU LU JING LUN XUE XIN FANG QIU(Institute of Genetics, Fudan Univerisity, Shanghai 200433) 《Cell Research》 SCIE CAS CSCD 1997年第1期21-29,共9页
This paper probes into the feasibility of increasing expression level of hFIX gene with endogenous nitron 1 sequence. hFIX minigene was obtained with middle sequence truncated nitron 1 inserted into the relative site ... This paper probes into the feasibility of increasing expression level of hFIX gene with endogenous nitron 1 sequence. hFIX minigene was obtained with middle sequence truncated nitron 1 inserted into the relative site of hFIX cDNA, and plasmid vector pKG5i’IX, retroviral vector GINaCi’IX were constructed. These vectors were transduced into target cells of PA317, C2C12, primary rabbit skin fibroblasts (RSF) and primary human skin fibroblasts (HSF). The expression level of mixed colonies are PA317/pKG5i’IX, 151 "g/106 cells/24h; PA317/GINaCi’IX, 308ng/106 cells/24 h; C2C12/G1 NaCi’IX, 186 ng/106 cells/24 h; RSF/GINaCi’IX, 1929 ng/106 cells/24 h; HSF/GlNaCi’IX, 1646 ng/106 cells/ 24 h. These results indicated that hFIX minigene with nitron 1 is able to increase the expression level to about 3 times of that of hFIX cDNA. Meanwhile, in order to study the application of hFIX minigene in the retroviral-mediated gene transfer system and refrain from nitron splicing during viral production, a retroviral vector GlNaCi’IXR with reversely inserted hFIX minigene expression cassette was constructed. The expression level of reverse constructor in PA317 cells was 390 ng/106 cells/24 h with 79% of bioactivity. PCR detection of HT/GlNaCi’IXR cells infected with PA317/ClNaCi’IXR supernatant confirmed the existence of nitron 1 sequence. These results suggested that expression vector with forward-inserted intronl-carrying hFIX expression cassette can be used in directed gene Human factor IX expression with nitron transfer, but when using the retroviral-mediated gene transfer system, reversely-inserted intronl-carrying hFIX expression cassette should be considered. 展开更多
关键词 基因内区1 hFIX 人类凝血因子IX 基因转化 体外高表达 反向插入序列 血友病B 基因治疗
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Isolation of a genomic DNA for Jatropha curcas ribosome inactivating protein and its tobacco transformation
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作者 罗言云 魏琴 +2 位作者 黄明星 徐莺 陈放 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期461-464,共4页
Genomic DNA for Jatropha curcas ribosome inactivating protein (JRIP) was cloned from total DNA of its leaves by polymerase chain reaction (PCR). The no intron character was confirmed. The plant expression vector pBI12... Genomic DNA for Jatropha curcas ribosome inactivating protein (JRIP) was cloned from total DNA of its leaves by polymerase chain reaction (PCR). The no intron character was confirmed. The plant expression vector pBI121-JRIP was constructed by inserting the JRIP gene into pBI121 plasmid. The recombinant Agrobacterium EHA105 strain harboring pBI121-JRIP was constructed by conducting pBI121-JRIP to strain EHA 105. PCR and Southern blotting were carried out, and the results proved that the JRIP gene was integrated into tobacco genome. It might provide a new material for disease resistance tobacco species breeding. 展开更多
关键词 麻风树 烟草 基因内区 核糖体 失活 基因
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THE ROLE OF INTRONIC HSE IN THE HEAT SHOCK INDUCED EXPRESSION OF HUMAN hsp 90β GENE
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作者 王晓哲 王艳林 +2 位作者 刘巨洪 吴宁华 沈(王羽)琲 《Chinese Medical Sciences Journal》 CAS CSCD 1998年第4期199-203,共5页
The first intron of human hsp 90β gene is not only essential m maintaining high constitutive expression but also critical for heat shock inducibility of the hsp90β gene. Typical HSEs in the first intron play a vital... The first intron of human hsp 90β gene is not only essential m maintaining high constitutive expression but also critical for heat shock inducibility of the hsp90β gene. Typical HSEs in the first intron play a vital role in the heat induced expression of human hsp90β gene. Slot blot analysis shows that hsp90β gene mRNA transcripts initiated from the 3'' of the first intron dominates over that of the first exon. The intronic HSEs of the hsp90β gene show much higher binding affinity toward the recombinant heat shock factor HSF1 than that of the recombinant heat shock factor HSF2. 展开更多
关键词 基因内区 热休克蛋白90β 基因转染 细胞培养
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肾、肾盂肿瘤
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《国外科技资料目录(医药卫生)》 CAS 2002年第4期146-146,共1页
0214630 大肠、肾同时性重复癌3例[日]/诃合合清//日临外会志.-2000,61(11).-3109~3116 冀医情0214631 能造成WT1突变的家族性Wilms氏瘤:能造成人工构建纯合性的基因内区的多态性/Pritchard Jones K//J Med Genet.-2000,37(5).-377~379
关键词 重复癌 基因内区 多态性 同时性 家族性 人工构建 肾盂肿瘤 纯合性 医科 大肠
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导致肥胖的基因机制
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《生物学通报》 2014年第5期27-27,共1页
搜寻肥胖的基因原因的工作将Fro基因的一个非编码区域置于了聚光灯下:这一内含子(基因内区)内的变异与肥胖症和Ⅱ型糖尿病的患病风险增加有关。
关键词 基因内区 肥胖症 机制 Ⅱ型糖尿病 非编码 内含子 聚光灯 变异
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Is the human dystrophin gene's intron structure related to its intron instability?
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作者 盛文利 陈江瑛 +1 位作者 朱良付 刘焯霖 《Chinese Medical Journal》 SCIE CAS CSCD 2003年第11期1733-1736,共4页
Objective To study the human dystrophin gene molecular deletion mechanism, we analyzed breakpoint regions within junction fragments of deletion-type patients and investigated whether the dystrophin gene's intron s... Objective To study the human dystrophin gene molecular deletion mechanism, we analyzed breakpoint regions within junction fragments of deletion-type patients and investigated whether the dystrophin gene's intron structure might be related to intron instability.Methods Junction fragments corresponding to exon 46 and 51 deletions were cloned. The breakpoint regions were sequenced, and the features of introns with available Genebank sequences were analyzed.Results An analysis of junction fragment sequences corresponding to exon 46 and 51 deletions showed that all 5' and 3' breakpoints are located within repeat sequences. No small insertions, small deletions, or point mutations are located near the breakpoint junctions. By analyzing the secondary structure of the junction fragments, we demonstrated that all junction fragment breakpoints are located in non-matching regions of single-stranded hairpin loops. A high concentration of repetitive elements is found to be a key feature of many dystrophin introns. In total, 34.8% of the overall dystrophin intron sequences is composed of repeat sequences.Conclusion Repeat elements in many dystrophin gene introns are the key to their structural bases and reflect intron instability. As a result of the primary DNA sequences, single-stranded hairpin loops form, increasing the instability of the gene, and forming the base for breaks in the DNA. The formation of the single-stranded hairpins can result in reattachment of two different breakpoints, producing a deletion. 展开更多
关键词 营养障碍基因 基因内区结构 稳定性 分子生物学 肌营养不良 发病机制
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