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991.
视力与视觉诱发电位的相关分析 总被引:4,自引:0,他引:4
对104例病人的图形翻转VEP的瞬态波形各参数,以及9例正常或近视学生的稳态曲线功率谱与视力之间的关系进行了多元相关统计分析,旨在探讨VEP的哪些参数可客观地评估视力.结果表明,瞬态VEP的波形参数中以13’格诱发的N_1P_1、P_1N_2的峰峰值及P_(100)潜伏期与视力的相关系数最大,故认为,分析视力时以平均P_(100)波的波幅值和P_(100)波潜伏期作指标较为灵敏;而稳态、VEP能谱曲线则显示,视力与平均相叶能谱或刺激频率点的能谱相关性较大,与二次谐波的相关性则小. 相似文献
992.
Yu-Huei Liu Cheng-Hsu Chen Shih-Yin Chen Ying-Ju Lin Wen-Ling Liao Chang-Hai Tsai Lei Wan Fuu-Jen Tsai 《Journal of biomedical science》2010,17(1):81
Background
Idiopathic membranous nephropathy (IMN) is one of the most common forms of autoimmune nephritic syndrome in adults. The purpose of this study is to evaluate whether polymorphisms of PLA2R1 affect the development of IMN. 相似文献993.
Coral reefs are under considerable pressure from global stressors such as elevated sea surface temperature and ocean acidification, as well as local factors including eutrophication and poor water quality. Marine sponges are diverse, abundant and ecologically important components of coral reefs in both coastal and offshore environments. Due to their exceptionally high filtration rates, sponges also form a crucial coupling point between benthic and pelagic habitats. Sponges harbor extensive microbial communities, with many microbial phylotypes found exclusively in sponges and thought to contribute to the health and survival of their hosts. Manipulative experiments were undertaken to ascertain the impact of elevated nutrients and seawater temperature on health and microbial community dynamics in the Great Barrier Reef sponge Rhopaloeides odorabile. R. odorabile exposed to elevated nutrient levels including 10 µmol/L total nitrogen at 31°C appeared visually similar to those maintained under ambient seawater conditions after 7 days. The symbiotic microbial community, analyzed by 16S rRNA gene pyrotag sequencing, was highly conserved for the duration of the experiment at both phylum and operational taxonomic unit (OTU) (97% sequence similarity) levels with 19 bacterial phyla and 1743 OTUs identified across all samples. Additionally, elevated nutrients and temperatures did not alter the archaeal associations in R. odorabile, with sequencing of 16S rRNA gene libraries revealing similar Thaumarchaeota diversity and denaturing gradient gel electrophoresis (DGGE) revealing consistent amoA gene patterns, across all experimental treatments. A conserved eukaryotic community was also identified across all nutrient and temperature treatments by DGGE. The highly stable microbial associations indicate that R. odorabile symbionts are capable of withstanding short-term exposure to elevated nutrient concentrations and sub-lethal temperatures. 相似文献
994.
Serum Level of Trefoil Factor 2 can Predict the Extent of Gastric Spasmolytic Polypeptide‐Expressing Metaplasia in the H. pylori‐Infected Gastric Cancer Relatives 下载免费PDF全文
995.
Tsai SP Wong A Mai E Chan P Mausisa G Vasser M Jhurani P Jakobsen MH Wong WL Stephan JP 《Nucleic acids research》2003,31(6):e25
Technologies allowing direct detection of specific RNA/DNA sequences occasionally serve as an alternative to amplification methods for gene expression studies. In these direct methods the hybridization of probes takes place in complex mixtures, thus specificity and sensitivity still limit the use of current technologies. To address these challenges, we developed a new technique called the nucleic acid capture assay, involving a direct multi-capture system. This approach combines a 3′-ethylene glycol scaffolding with the incorporation of 2′-methoxy deoxyribonucleotides in the capture sequences. In our design, all nucleotides other than those complementary to the target mRNA have been replaced by an inert linker, resulting in significant reductions in non-specific binding. We also provide a versatile method to detect the presence of captured targets by using specific labeled probes with alkaline phosphatase-conjugated anti-label antibodies. This direct, flexible and reliable technique for gene expression analysis is well suited for high-throughput screening and has potential for DNA microarray applications. 相似文献
996.
997.
Relationships among non-Acremonium sp. fungal endophytes in five grass species. 总被引:1,自引:1,他引:1 下载免费PDF全文
Z Q An M R Siegel W Hollin H F Tsai D Schmidt C L Schardl 《Applied microbiology》1993,59(5):1540-1548
Many cool-season grasses (subfamily Pooideae) possess maternally transmitted fungal symbionts which cause no known pathology and often enhance the ecological fitness and biochemical capabilities of the grass hosts. The most commonly described endophytes are the Acremonium section Albo-lanosa spp. (Acremonium endophytes), which are conidial anamorphs (strictly asexual forms) of Epichloë typhina. Other endophytes which have been noted are a Gliocladium-like fungus in perennial ryegrass (Lolium perenne L.) and a Phialophora-like fungus in tall fescue (Festuca arundinacea Schreb.). Here, we report the identification of additional non-Acremonium sp. endophytes (herein designated p-endophytes) in three more grass species: Festuca gigantea, Festuca arizonica, and Festuca pratensis. In each grass species, the p-endophyte was cosymbiotic with an Acremonium endophyte. Serological analysis and sequence determinations of variable portions of their rRNA genes indicated that the two previously identified non-Acremonium endophytes are closely related to each other and to the newly identified p-endophytes. Therefore, the p-endophytes represent a second group of widely distributed grass symbionts. 相似文献
998.
Palmitoyl-protein thioesterase-1 (PPT1) deficiency causes infantile neuronal ceroid lipofuscinosis (INCL), a devastating childhood neurodegenerative storage disorder. We previously reported that neuronal apoptosis in INCL is mediated by endoplasmic reticulum-stress. ER-stress disrupts Ca2+-homeostasis and stimulates the expression of Ca2+-binding proteins. We report here that in the PPT1-deficient human and mouse brain the levels of S100B, a Ca2+-binding protein, and its receptor, RAGE (receptor for advanced glycation end-products) are elevated. We further demonstrate that activation of RAGE signaling in astroglial cells mediates pro-inflammatory cytokine production, which is inhibited by SiRNA-mediated suppression of RAGE expression. We propose that RAGE signaling contributes to neuroinflammation in INCL. 相似文献
999.
1000.
Smad Anchor for Receptor Activation (SARA) has been reported as a critical role in TGF-β signal transduction by recruiting non-activated Smad2/3 to the TGF-β receptor and ensuring appropriate subcellular localization of the activated receptor-bound complex. However, controversies still exist in previous reports. In this study, we describe the expression of two SARA isoforms, SARA1 and SARA2, in mice and report the generation and characterization of SARA mutant mice with FYVE domain deletion. SARA mutant mice developed normally and showed no gross abnormalities. Further examination showed that the TGF-β signaling pathway was indeed altered in SARA mutant mice, with the downregulation of Smad2 protein expression. The decreasing expression of Smad2 was caused by enhancing Smurf2-mediated proteasome degradation pathway. However, the internalization of TGF-β receptors into the early endosome was not affected in SARA mutant mouse embryonic fibroblasts (MEFs). Moreover, the downregulation of Smad2 in SARA mutant MEFs was not sufficient to disrupt the diverse cellular biological functions of TGF-β signaling, including growth inhibition, apoptosis, senescence, and the epithelial-to-mesenchymal transition. Our results indicate that SARA is not involved in the activation process of TGF-β signal transduction. Using a two-stage skin chemical carcinogenesis assay, we found that the loss of SARA promoted skin tumor formation and malignant progression. Our data suggest a protective role of SARA in skin carcinogenesis. 相似文献