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971.
Ding Q  Wu Z  Guo Y  Zhao C  Jia Y  Kong F  Chen B  Wang H  Xiong S  Que H  Jing S  Liu S 《Proteomics》2006,6(2):505-518
The inability of the CNS to regenerate in adult mammals propels us to reveal associated proteins involved in the injured CNS. In this paper, either thoracic laminectomy (as sham control) or thoracic spinal cord transection was performed on male adult rats. Five days after surgery, the whole spinal cord tissue was dissected and fractionated into water-soluble (dissolved in Tris buffer) and water-insoluble (dissolved in a solution containing chaotropes and surfactants) portions for 2-DE. Protein identification was performed by MS and further confirmed by Western blot. As a result, over 30 protein spots in the injured spinal cord were shown to be up-regulated no less than 1.5-fold. These identified proteins possibly play various roles during the injury and repair process and may be functionally categorized as several different groups, such as stress-responsive and metabolic changes, lipid and protein degeneration, neural survival and regeneration. In particular, over-expression of 11-zinc finger protein and glypican may be responsible for the inhibition of axonal growth and regeneration. Moreover, three unknown proteins with novel sequences were found to be up-regulated by spinal cord injury. Further characterization of these molecules may help us come closer to understanding the mechanisms that underlie the inability of the adult CNS to regenerate.  相似文献   
972.
贾彩风  李悦 《植物学报》2006,23(2):186-191
探索华山松(Pinus armandii)体细胞胚胎发生技术对其实施规模化无性繁殖和开展遗传转化具有重要意义。本文以1/2LM为基本培养基, 通过激素调节等措施对华山松的胚性愈伤组织诱导和幼胚的离体培养技术进行了初步研究。研究结果: 胚性愈伤组织诱导率最高可达52.71%, 但愈伤组织继代培养后没有体细胞胚胎的分化; 首次从其子叶期的幼胚中直接诱导出具有根和茎的完整植株, 诱导率达92%以上。文章确认了采集的幼胚发育状态对胚性愈伤组织的诱导有重要影响, 并对诱导的培养条件等进行了探讨。  相似文献   
973.
促炎基因ALOX5AP基因多态性与脑卒中的相关性研究   总被引:6,自引:0,他引:6  
白三烯是作用较强的促炎症因子,在动脉粥样硬化的发生发展中发挥着重要作用。5-脂氧合酶激活蛋白是白三烯合成的关键调控因素,通过全基因组扫描的连锁分析和关联分析发现编码5-脂氧合酶激活蛋白的基因ALOX5AP在白种人中与心肌梗塞和脑卒中的患病风险相关。然而,目前尚无关于该基因与亚洲人脑卒中患病风险的遗传学资料。本研究探讨了ALOX5AP基因多态与脑卒中及其亚型易感性的关系。采用PCR—RFLP方法,对来自7个临床中心的1713名对照和1773名脑卒中患者检测了ALOX5AP基因的4个SNPs:SG13S25、SG13S114、SG13S89和SG13S32。多元logistic回归方法校正传统危险因素后分析基因多态与脑卒中患病风险的独立相关性。结果表明,人群未发现SG13S25和SG13S32具有多态性;ALOX5AP基因多态SG13S114A等位基因频率在男性脑梗塞组显著高于对照组(33.6%VS29.2%;P=0.014),SG13S114AA基因型增加男性脑梗塞1.62倍的发病风险(95%CI:1.1-2.35:P=0.012)。多态SG13S89G/A与脑梗塞的易感性不相关。单体型分析表明单体型频率在脑卒中患者和对照组间无显著的统计学差异。因此,本研究结果提示ALOX5AP基因多态的等位基因和基因型频率在东、西方人群存在种族差异,SG13S114AA基因型增加中国人群男性脑梗塞的易感性。  相似文献   
974.
本文试图从生理生化的角度对假苍耳(Iva xanthifolia)生活史进程中可溶性糖类、赤霉素、单宁以及黄酮的变化进行探讨。通过对假苍耳在生长发育期间几种生理生化指标的测定, 结果表明, 在假苍耳生活史进程的不同阶段, 其体内各种代谢产物的含量基本都在种子或芽阶段具有最高含量。此外, 不同发育阶段可溶性还原糖含量的变化规律相似: 芽>花序>苗>成株>种子。除在花序和苗阶段没有测到海藻糖, 其他各阶段海藻糖的含量变化如下: 芽>成株>种子。另外, 只有在种子阶段检测到棉子糖, 其含量为15.43 mg.g-1。赤霉素含量的变化规律如下: 种子>芽≈苗≈花序>成株。单宁含量的变化趋势: 种子>成株>苗>芽>花序。黄酮含量的变化趋势: 种子>芽>成株≈花序>苗。值得注意的是, 当单宁/黄酮的比值接近1时, 植物体内需要的单宁和黄酮的含量则相对较低; 相反, 当单宁/黄酮的比值接近0时, 植物体内需要的单宁和黄酮的含量则较高。  相似文献   
975.
Two powdery mildew resistance genes were Identified from Aegilops tauschll accessions Y201 and Y212 and mapped using two different F2 populations derived from the crosses between susceptible accession Y2272 and Y201, and susceptible accession Y2263 and Y212. Genetic analysis of resistance to powdery mildew Indicated that the resistance of Y201 was controlled by a single dominant gene, whereas the resistance of Y212 was controlled by a single recessive gene. We have temporarily designated these genes as PmY201 and PmY212, respectively. By bulk segregation analysis, six mlcrosatelllte markers Including Xgwm174, cfd26, cfd57, cfdl02, Xgwm583 and Xgwm639 were found to be linked to PraY201 with genetic distances of 5.2, 7.7, 9.6, 12.5, 20.2 and 22.1 cM, respectively. Five SSR markers, including cfd57, Xgwm182, cfd7, cfd102, and cfd12, were found to be linked to PmY212 with distances of 5.6, 7.2, 11.5, 14.7, and 18.5 cM, respectively. According to the locations of the linked markers, the two resistance genes were located In the 5DL region. Based on the chromosomal locations and the resistance patterns of the two genes, we propose that PmY201 and PmY212 are two novel powdery mildew resistance genes, and are suitable for marker-assisted selection.  相似文献   
976.
Talgu Genlc Male Sterile Wheat (TGMSW; Trltlcum aestlvum L.), a dominant genic male sterile germplasm, is of considerable value in the genetic Improvement of wheat because of Its stable Inherence, complete male abortion, and high cross-fertilization rate. To Identify specially transcribed genes In sterile anther, a suppression subtractlve hybridization (aSH) library was constructed with sterile anther as the tester and fertile anther as the driver. A total of 2 304 SSH Inserts amplified by polymerase chain reaction were arrayed using robotic printing. The cDNA arrays were hybridized with 32P-labeled probes prepared from the RNA of forward- and reverse-subtracted anthers. Ninety-six clones were scored as upregulated in sterile anthers compared with the corresponding fertile anthers and some clones were selected for sequencing and analysis In GenBank. Based on their putative functions, 87 non-redundant clones were classified Into the following groups: (i) eight genes Involved In metabolic processes; (11) four material transportation genes; (iii) three signal transductlon-assoclated genes; (iv) four stress response and senescence-associated protein genes; (v) seven other functional protein genes; (vi) five genes with no known function; and (vii) another 56 genes with no match to the databases. To test the hybridization efficiency, eight genes were selected and analyzed by Northern blot. The results of the present study provide a comprehensive overview of the genes and gene products Involved In anther abortion In TGMSW.  相似文献   
977.
978.
979.
目的:研究抗动脉粥样硬化核酸疫苗的安全性。方法:观察该质粒在小鼠组织中的分布和急性毒性,井在正常给药的情况下对新西兰大白兔进行6个月毒性试验。采用肌肉注射20μg/只和100μg/只,用P(温法检测外源基因在小鼠组织的分布和存留时间;同样采用肌肉注射,对最高剂量达到到50kg/kg体重的小鼠进行急性毒性试验。结果:实验证明该核酸疫苗在注射部位可存留时间为8周,其他组织如心、肝、脾、肺、肾、脑和生殖器官也有低水平分布,急毒试验显示,在剂量达到有效荆量的60倍的情况下,无可观察到的毒性反应发生,小鼠血液学和生化指标亦无异常;新西兰大白兔毒性观察,体内生化指标以及解剖学研究结果表明,该药无可观察到的毒性反应发生。结论:该核酸疫苗无可观察到的明显毒性反应,安全性良好。  相似文献   
980.
Colony stimulating factor-1 (CSF-1) is the primary regulator of the mononuclear phagocytic lineage acting through its transmembrane tyrosine kinase receptor, CSF-1R, that is the product of the c-fms proto-oncogene. Null mutations in either the ligand or the receptor genes result in a severe osteopetrosis as well as a number of other phenotypes, including reproductive defects and perturbations in organ development. The CSF-1R is also expressed in oocytes, myoblast progenitors, decidual, and trophoblastic cells. To distinguish cell type specific phenotypes, we have created a conditional allele of the Csf1r by placing LoxP sites around Exon 5 of the Csf1r gene in mice. Excision of this floxed sequence results in a null allele that in the homozygous state gives a phenotype indistinguishable of the complete Csf1r null mutant mouse. This conditional allele will prove extremely valuable to study the spatial and temporal roles of CSF-1R.  相似文献   
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