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151.
褐飞虱饲养于不同水稻品种、不同生育期以及不同种群密度条件下,5龄若虫翅芽长度与成虫翅型具有稳定的相关性:翅芽长于1.10mm羽化后为长翅型雌虫,介于0.96~1.09mm之间为长翅型雄虫或短翅型雌虫,小于0.95mm为短翅型雄虫。根据5龄若虫翅芽长度结合外生殖器特征,编制了成虫翅型检索表。由此,可在5龄若虫期预测成虫的翅型和种群盛衰的趋势。 相似文献
152.
Top-down modulations from dorsal stream in lexical recognition: an effective connectivity FMRI study
Both the ventral and dorsal visual streams in the human brain are known to be involved in reading. However, the interaction of these two pathways and their responses to different cognitive demands remains unclear. In this study, activation of neural pathways during Chinese character reading was acquired by using a functional magnetic resonance imaging (fMRI) technique. Visual-spatial analysis (mediated by the dorsal pathway) was disassociated from lexical recognition (mediated by the ventral pathway) via a spatial-based lexical decision task and effective connectivity analysis. Connectivity results revealed that, during spatial processing, the left superior parietal lobule (SPL) positively modulated the left fusiform gyrus (FG), while during lexical processing, the left SPL received positive modulatory input from the left inferior frontal gyrus (IFG) and sent negative modulatory output to the left FG. These findings suggest that the dorsal stream is highly involved in lexical recognition and acts as a top-down modulator for lexical processing. 相似文献
153.
154.
Xiaohuan Cheng Junfa Ding Fang Zheng Xin Zhou Chenling Xiong 《Molecular biology reports》2009,36(8):2053-2057
Familial hypercholesterolemia (FH) (OMIM 143890) is an autosomal dominantly inherited disease mainly caused by mutations of
the gene encoding the low density lipoprotein receptor (LDLR) and Apolipoprotein (Apo) B. First the common mutation R3500Q
in ApoB gene was determined using PCR/RFLP method. Then the LDLR gene was screened for mutations using Touch-down PCR, SSCP
and sequencing techniques. Furthermore, the secondary structure of the LDLR protein was predicted with ANTHEPROT5.0. The R3500Q
mutation was absent in these two families. A heterozygous p.W483X mutation of LDLR gene was identified in family A which caused
a premature stop codon, while a homozygous mutation p.A627T was found in family B. The predicted secondary structures of the
mutant LDLR were altered. We identified two known mutations (p.W483X, p.A627T) of the LDLR gene in two Chinese FH families
respectively. 相似文献
155.
温度、盐度对强壮箭虫耗氧率和窒息点的影响 总被引:1,自引:0,他引:1
研究了不同温度、盐度下强壮箭虫的耗氧率和窒息点.结果表明:温度和盐度均对强壮箭虫的耗氧率和比耗氧率有显著影响.试验温度在5℃-25℃,强壮箭虫个体耗氧率(IO)和比耗氧率(SO)开始随温度的升高而升高,之后呈明显下降趋势.其回归方程分别为y=0.0058x3 -0.2956x2+4.415x-8.7816(R2=0.99,P<0.05)和y=0.0011x3 -0.0546x2+0.8161x-1.6232(R2=0.99,P<0.05),数值分别为6.30~11.71μg·ind-1·h-1和1.22 ~2.16μg· mg-1·h-1,窒息点为4.18~6.87 mg·L-1.盐度10 ~40条件下,IO和SO随盐度的升高逐渐下降,回归方程分别为y=-0.0068x2 -0.1412x+21.702(R2=0.89,P<0.05)和y=-0.0013x2-0.0261x+4.0114( R2 =0.89,P<0.05),数值分别为4.98~17.73μg ·ind-1·h-1和0.92~3.56 μg·mg-1 ·h-1,窒息点为4.02~6.24 mg·L-1.对强壮箭虫与其他水生动物的耗氧率和窒息点进行比较得出,强壮箭虫是一种狭氧性浮游动物. 相似文献
156.
湖北地区宫颈癌组织中人乳头瘤病毒16型E7基因的分离、克隆和序列分析 总被引:5,自引:1,他引:5
采用加端聚合酶链反应技术,从湖北地区一宫颈癌患者癌组织DNA中分离出人乳头瘤病毒16型(HPV16)E7基因,并在pUC18载体中克隆。经限制性核酸内切酶分析和DNA序列分析,确认了含HPV16E7重组克隆质粒,命名pHPV16E7─HB。DNA序列分析表明,HPV16E7─HB基因全长294bp(与报道的标准株基因长度相同),但其核苷酸顺序中有两处发生了C→T突变,即第43位密码子CAA变为TAA,第76位CGT变为TGT;前者使谷氨酰胺密码子变为终止密码,即无义奕变(nonsensemutation)。这种突变发生在294个碱基的DNA扩增产物之中,不像是PCR本身的错配,而很可能是湖北株与标准株之间的结构差异。 相似文献
157.
158.
The mitochondrion is a key organelle of eukaryotic cell that provides the energy for cellular activities. Correctly identifying submitochondria locations of proteins can provide plentiful information for understanding their functions. However, using web-experimental methods to recognize submitochondria locations of proteins are time-consuming and costly. Thus, it is highly desired to develop a bioinformatics method to predict the submitochondria locations of mitochondrion proteins. In this work, a novel method based on support vector machine was developed to predict the submitochondria locations of mitochondrion proteins by using over-represented tetrapeptides selected by using binomial distribution. A reliable and rigorous benchmark dataset including 495 mitochondrion proteins with sequence identity ≤25 % was constructed for testing and evaluating the proposed model. Jackknife cross-validated results showed that the 91.1 % of the 495 mitochondrion proteins can be correctly predicted. Subsequently, our model was estimated by three existing benchmark datasets. The overall accuracies are 94.0, 94.7 and 93.4 %, respectively, suggesting that the proposed model is potentially useful in the realm of mitochondrion proteome research. Based on this model, we built a predictor called TetraMito which is freely available at http://lin.uestc.edu.cn/server/TetraMito. 相似文献
159.
Phosphoproteome profiling of human skin fibroblast cells in response to low- and high-dose irradiation 总被引:4,自引:0,他引:4
Yang F Stenoien DL Strittmatter EF Wang J Ding L Lipton MS Monroe ME Nicora CD Gristenko MA Tang K Fang R Adkins JN Camp DG Chen DJ Smith RD 《Journal of proteome research》2006,5(5):1252-1260
A hallmark of the response to high-dose radiation is the up-regulation and phosphorylation of proteins involved in cell cycle checkpoint control, DNA damage signaling, DNA repair, and apoptosis. Exposure of cells to low doses of radiation has well documented biological effects, but the underlying regulatory mechanisms are still poorly understood. The objective of this study is to provide an initial profile of the normal human skin fibroblast (HSF) phosphoproteome and explore potential differences between low- and high-dose irradiation responses at the protein phosphorylation level. Several techniques including Trizol extraction of proteins, methylation of tryptic peptides, enrichment of phosphopeptides with immobilized metal affinity chromatography (IMAC), nanoflow reversed-phase HPLC (nano-LC)/electrospray ionization, and tandem mass spectrometry were combined for analysis of the HSF cell phosphoproteome. Among 494 unique phosphopeptides, 232 were singly phosphorylated, while 262 peptides had multiple phosphorylation sites indicating the overall effectiveness of the IMAC technique to enrich both singly and multiply phosphorylated peptides. We observed approximately 1.9-fold and approximately 3.6-fold increases in the number of identified phosphopeptides in low-dose and high-dose samples respectively, suggesting both radiation levels stimulate cell signaling pathways. A 6-fold increase in the phosphorylation of cyclin dependent kinase (cdk) motifs was observed after low- dose irradiation, while high-dose irradiation stimulated phosphorylation of 3-phosphoinositide-dependent protein kinase-1 (PDK1) and AKT/RSK motifs 8.5- and 5.5-fold, respectively. High- dose radiation resulted in the increased phosphorylation of proteins involved in cell signaling pathways as well as apoptosis while low-dose and control phosphoproteins were broadly distributed among biological processes. 相似文献
160.