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991.
Aliev G Liu J Shenk JC Fischbach K Pacheco GJ Chen SG Obrenovich ME Ward WF Richardson AG Smith MA Gasimov E Perry G Ames BN 《Journal of cellular and molecular medicine》2009,13(2):320-333
Brain function declines with age and is associated with diminishing mitochondrial integrity. The neuronal mitochondrial ultrastructural changes of young (4 months) and old (21 months) F344 rats supplemented with two mitochondrial metabolites, acetyl-L-carnitine (ALCAR, 0.2%[wt/vol] in the drinking water) and R-α-lipoic acid (LA, 0.1%[wt/wt] in the chow), were analysed using qualitative and quantitative electron microscopy techniques. Two independent morphologists blinded to sample identity examined and scored all electron micrographs. Mitochondria were examined in each micrograph, and each structure was scored according to the degree of injury. Controls displayed an age-associated significant decrease in the number of intact mitochondria (P = 0.026) as well as an increase in mitochondria with broken cristae (P < 0.001) in the hippocampus as demonstrated by electron microscopic observations. Neuronal mitochondrial damage was associated with damage in vessel wall cells, especially vascular endothelial cells. Dietary supplementation of young and aged animals increased the proliferation of intact mitochondria and reduced the density of mitochondria associated with vacuoles and lipofuscin. Feeding old rats ALCAR and LA significantly reduced the number of severely damaged mitochondria (P = 0.02) and increased the number of intact mitochondria (P < 0.001) in the hippocampus. These results suggest that feeding ALCAR with LA may ameliorate age-associated mitochondrial ultrastructural decay and are consistent with previous studies showing improved brain function. 相似文献
992.
Martin R. Jones Shu Yi Chua Nigel J. O’Neil Robert C. Johnsen Ann M. Rose David L. Baillie 《Molecular genetics and genomics : MGG》2009,282(1):37-46
Genomic rearrangements are widely used in Caenorhabditis elegans research but many remain incompletely characterized at the physical level. We have used oligo-array comparative genomic analysis
to assess the physical structure of 20 deficiencies and a single duplication of chromosome V. We find that while deletions
internal to the chromosome appear simple in structure, terminal deletions are complex, containing duplications in addition
to the deletion. Additionally, we confirm that transposon-induced deficiencies contain breakpoints that initiate at Tc1 elements.
Finally, 13 of these deficiencies are known to suppress recombination far beyond the extent of the deletion. These deficiencies
fall into two classes: strong and weak suppressors of adjacent recombination. Analysis of the deleted regions in these deficiencies
reveals no common physical sites to explain the observed differences in recombination suppression. However, we find a strong
correlation between the size of the rearranged chromosome and the severity of recombination suppression. Rearranged chromosomes
that have a minor effect on recombination fall within 2% of normal chromosome size. Our observations highlight the use of
array-based approaches for the analysis of rearranged genomes, revealing previously unidentified deficiency characteristics
and addressing biologically relevant questions. 相似文献
993.
目的:探讨醛糖还原酶(AR)基因启动区C(-106)T多态性与糖尿病视网膜病变(DR)的关系。方法:235例江苏汉族人群,其中2型糖尿病无视网膜病变组(NDR)63例,2型糖尿病伴视网膜病变组(DR)82例,正常对照组(YC)90例,用PCR-RFLP方法检测AR基因C(-106)T基因型,比较各组等位基因及基因型分布频率。结果:未发现NDR组和NC组之间AR基因C(-106)T各等位基因及基因型频率有显著差异(P分别为0.4505,0.7279);DR组中CT及TT基因型频率均高于NC组,CC基因型频率低于NC组(P=0.0239),DR组T等位基因频率显著高于NC组,C等位基因频率显著低于NC组(P=0.0038)。结论:AR基因启动区C(-106)T多态性与江苏汉族人群DR相关,T等位基因可能是DR的遗传危险因子。 相似文献
994.
潘氏细胞是位于小肠腺底部的浆液性腺上皮细胞,其主要特征是细胞顶部有大量粗大的嗜酸性分泌颗粒,内含防御素、溶菌酶、sIgA等多种抗菌物质。表达于潘氏细胞的NOD2、Toll样受体9、肝癌-肠-胰腺/胰腺炎相关蛋白、RegⅢγ、肿瘤坏死因子仅、粒细胞-巨噬细胞集落刺激因子、白介素-17等也是免疫与炎症反应的重要成分。金属硫蛋白、富半胱氨酸肠蛋白、潘氏细胞锌结合蛋白等金属结合蛋白均分布于潘氏细胞,提示潘氏细胞参与金属代谢。潘氏细胞是构成肠黏膜屏障的重要细胞成分。NOD2单核苷酸多态性与克罗恩病有关。潘氏细胞化生常发生于胃、大肠的炎症与肿瘤病变,其病理意义有待于进一步研究。 相似文献
995.
植物亚原生质体中的胞质体和微原生质体在植物遗传改良等应用方面上具有重要意义,就国内外在胞质体和微原生质体分离和融合等方面的研究进行了综述,同时对研究中存在的问题提出了展望。 相似文献
996.
小麦温光型两系恢复系MR168的选育与利用初报 总被引:3,自引:1,他引:2
利用不同生态区冬、春小麦地理远缘杂交,育成适应西南冬麦区生态条件的温光型两系恢复系材料MR168.其主要特点是早熟,分蘖力较强,成穗率高;株高适中,穗大粒多,穗层整齐,穗子方正,开花期较集中,花药较大且外露率高;后期落黄好,灌浆速度快;高抗条锈病和白粉病.经初步利用表明,MR168所配组合对早春低温具有较强的抵抗力,不同年份其杂种一代结实正常,丰产性好,适应性广,抗病力强,兼抗条锈病和白粉病,具有较好的应用前景. 相似文献
997.
中国部分地区马铃薯寄主上致病疫霉SSR基因型分析 总被引:2,自引:1,他引:1
利用两对SSR引物对两个基因座Pi4B和Pi4G进行了PCR扩增,测定了中国部分地区66个致病疫霉Phyophthora infestans(马铃薯晚疫病菌)菌株和2个参考菌株的SSR基因型,并对菌株的基因型进行了鉴定和命名.在被测定的66个致病疫霉菌株中,共产生了7种SSR基因型D-03,D-05,D-06,G-02,H-01,F-01和F-06,其中F-06为本研究新命名的基因型.F-01基因型菌株53个,占总菌株数目的80.3%,该基因型为中国致病疫霉的优势基因型.在对两个基因座Pi4B和Pi4G产生的等位基因统计分析发现基因座Pi4B产生的多样性比Pi4G高.对SSR数据揭示的河北、黑龙江和云南3个不同省份致病疫霉遗传多样性的比较发现,河北省和黑龙江省致病疫霉遗传多样性几乎相同,然而与云南省致病疫霉有较大的遗传差异.此外,发现致病疫霉SSR基因型与其对甲霜灵抗性无相关性. 相似文献
998.
目的:探讨数据管理系统DM2检验结果自动确认范围设定.方法:统计分析2008年全自动流水线测定项目检验结果.以1%和99%分位作为自动审核上下限,查看2009年3月数据自动审核通过率并分析未通过审核原因.结果:2008年数据统计结果与项目的参考范围有差异,数据自动审核通过率超过75%,未通过审核数据中超出自动审核范围的结果占23%以上.结论:通过对实验室数据的回顾性分析,设定合理的自动审核范围,充分发挥全自动流水线和数据管理系统的效能,提高检测效率,为临床提供快捷、准确的服务. 相似文献
999.
The topological architecture of the cerebral anatomical network reflects the structural organization of the human brain. Recently, topological measures based on graph theory have provided new approaches for quantifying large-scale anatomical networks. Diffusion MRI studies have revealed the efficient small-world properties and modular structure of the anatomical network in normal subjects. However, no previous study has used diffusion MRI to reveal changes in the brain anatomical network in early blindness. Here, we utilized diffusion tensor imaging to construct binary anatomical networks for 17 early blind subjects and 17 age- and gender-matched sighted controls. We established the existence of structural connections between any pair of the 90 cortical and sub-cortical regions using deterministic tractography. Compared with controls, early blind subjects showed a decreased degree of connectivity, a reduced global efficiency, and an increased characteristic path length in their brain anatomical network, especially in the visual cortex. Moreover, we revealed some regions with motor or somatosensory function have increased connections with other brain regions in the early blind, which suggested experience-dependent compensatory plasticity. This study is the first to show alterations in the topological properties of the anatomical network in early blindness. From the results, we suggest that analyzing the brain''s anatomical network obtained using diffusion MRI data provides new insights into the understanding of the brain''s re-organization in the specific population with early visual deprivation. 相似文献
1000.