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61.
矮牵牛是一种草本花卉,主要用来布置花坛,但病毒侵染却严重地影响其观赏价值。国内外有关危害矮牵牛的病毒报道较多[1,2],但较系统研究矮牵牛病毒病的报道较少,本文从矮牵牛病毒鉴定、优势病毒种类确定及防治矮牵牛病毒病进行了初步研究,现报道如下:材料与方法... 相似文献
62.
Shujun Chang Clint W. Magill Jane M. Magill Franklin Fong Ronald J. Newton 《Plant Molecular Biology Reporter》1992,10(4):362-366
A procedure to test for DNA methylation at sites recognized by methylation-sensitive restriction endonucleases is described.
The procedure is based on the assumption that the polymerase chain reaction (PCR) will amplify sequences between two primers
only if the target DNA is intact after digestion. A carrot (Daucus carota) cell line that is heterozygous for two sequenced alleles ofDc8, a gene which is expressed during the later stages of embryogenesis provided an ideal source of DNA for developing and testing
protocols. The promoters of the two alleles differs significantly in length between two sites used for primers, and only one
promoter has a GATC (Sau 3A1 orMbo I) site. This allowed development of a protocol where only the sequence lacking the GATC site was amplified to detectable
levels following digestion of DNA withMbo I which is insensitive to symmetric methylation withm4C orm5C. 相似文献
63.
64.
Hongzhuo Xia Jianyu Zhu Zhuomeng Zheng Peiyao Xiao Xiaohui Yu Muyao Wu Lian Xue Xi Xu Xinyu Wang Yuxuan Guo Chanjuan Zheng Siyu Ding Yian Wang Xiaoning Peng Shujun Fu Junjun Li Xiyun Deng 《The journal of gene medicine》2024,26(1):e3647
Breast cancer is the most commonly diagnosed cancer among women. The primary treatment options include surgery, radiotherapy, chemotherapy, targeted therapy and hormone therapy. The effectiveness of breast cancer therapy varies depending on the stage and aggressiveness of the cancer, as well as individual factors. Advances in early detection and improved treatments have significantly increased survival rates for breast cancer patients. Nevertheless, specific subtypes of breast cancer, particularly triple-negative breast cancer, still lack effective treatment strategies. Thus, novel and effective therapeutic targets for breast cancer need to be explored. As substrates of protein synthesis, amino acids are important sources of energy and nutrition, only secondly to glucose. The rich supply of amino acids enables the tumor to maintain its proliferative competence through participation in energy generation, nucleoside synthesis and maintenance of cellular redox balance. Amino acids also play an important role in immune-suppressive microenvironment formation. Thus, the biological effects of amino acids may change unexpectedly in tumor-specific or oncogene-dependent manners. In recent years, there has been significant progress in the study of amino acid metabolism, particularly in their potential application as therapeutic targets in breast cancer. In this review, we provide an update on amino acid metabolism and discuss the therapeutic implications of amino acids in breast cancer. 相似文献
65.
Hong L Han Y Li S Yang J Gong T Li J Zheng J Zhang H Zhao Q Wu K Fan D 《Cell biology international》2011,35(4):321-324
Here, we have first investigated the roles of ZNRD1 in angiogenesis of leukaemia. The leukaemia cell line K562 was transfected with the vector that included the full-length cDNA of ZNRD1, then the growth and angiogenesis of cells were detected. Up-regulation of ZNRD1 could significantly inhibit the growth of cells, reduce tumour microvessel densities and inhibit the VEGF (vascular endothelial growth factor) production. The results of human miRNA array and real-time PCR showed that ZNRD1 could significantly up-regulate the expression of miR-214 and down-regulate the expression of miR-296. Taken together, ZNRD1 might inhibit tumour angiogenesis and could be considered as a target for leukaemia therapy. 相似文献
66.
Yu Liu Shouxian Wang Dianpeng Zhang Shujun Wei Shuang Zhao Sanfeng Chen Feng Xu 《Antonie van Leeuwenhoek》2013,104(6):1039-1047
Four Gram-negative-staining, facultatively anaerobic bacterial isolates were obtained from a fruiting body of the edible mushroom Pleurotus eryngii showing symptoms of soft rot disease in Beijing, China. Partial 16S rRNA gene sequencing, together with partial rpoB sequencing, placed these isolates in the genus Pantoea. Multilocus sequence analysis based on the partial sequences of gyrB, rpoB, infB and atpD revealed Pantoea dispersa and Pantoea gaviniae as their closest phylogenetic relatives and indicated that these isolates constituted a possible novel species. DNA–DNA hybridization studies confirmed the classification of the new isolates as a novel species and phenotypic tests allowed for differentiation from the closest phylogenetic neighbours. The name Pantoea beijingensis sp. nov. [type strain LMG 27579T = KCTC 32406T = JZB2120001T (deposited at Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences)] is proposed. 相似文献
67.
Jiao Xu Zhongqiong Yin Li Li Anchun Cheng Renyong Jia Xu Song Hongke Lu Shujun Dai Cheng Lv Xiaoxia Liang Changliang He Ling Zhao Gang Su Gang Ye Fei Shi 《PloS one》2013,8(6)
Duck viral enteritis (DVE) is an acute, contagious herpesvirus infection of ducks, geese, and swans of all ages and species. This disease has been responsible for significant economic losses in domestic and wild waterfowl as a result of mortality, and decreased egg production. Resveratrol is a naturally occurring phytoalexin in specific plants and exhibits inhibitory activity against many kinds of virus. In this paper, resveratrol was found to inhibit duck enteritis virus (DEV) replication in a dose-dependent manner, with a 50% inhibition concentration of 3.85 μg/mL. The inhibition in virus multiplication in the presence of resveratrol was not attributed to direct inactivation or inhibition of virus attachment to the host cells, but to the inhibition of viral multiplication in host cells. The assay of the time of addition limited the drug effect during the first 8 h of infection. This conclusion was supported by the ultrastructure images of the early stage of DEV infection, which showed that the replication of virus nucleic acid and the formation of the capsid in the cell nucleus were suppressed. In the indirect immunofluorescence assay, proteins expression in DEV infected duck embryo fibroblasts (DEFs) within 24 h post-infection (p.i.) was also effectively suppressed by resveratrol. In summary, the resveratrol has a good activity against DEV infection in vitro, which could be attributed to that fact that several essential immediate early viral proteins for virus replication were impacted by resveratrol. 相似文献
68.
Michael B. Sherman Joanita Jakana Shujun Sun Paul Matsudaira Wah Chiu Michael F. Schmid 《Journal of structural biology》1997,120(3):245-256
Structures of highly ordered biological bundles have unique features which call for special experimental and computational methods in electron cryomicroscopy. They can be considered as three-dimensional quasi-crystals and reconstructed using a crystallographic approach. However, they are neither “infinitely” large with respect to the borders of the bundle, nor are they a single unit cell in thickness along the viewing direction. Also, because of their shape, bundles do not generally have a preferred azimuthal orientation, which poses challenges for orientation estimation and refinement. We developed a strategy for recording and processing electron cryomicroscopic images that differs from classical two-dimensional crystalline reconstruction techniques. These developments allowed us to merge data from tomographic tilt series of ice-embedded acrosomal bundles. The goal is to determine accurately amplitudes and phases at the diffraction maxima in terms ofhklindices, and compute a three-dimensional map from the diffraction data. 相似文献
69.
达乌尔黄鼠冬眠期间体温的变化和冬眠模式 总被引:2,自引:0,他引:2
用植入式半导体温度记录元件iButton 记录了达乌尔黄鼠冬眠季节及其前后的体温,分析了其冬眠模式和体温调节特点。结果显示:1)实验室条件下,达乌尔黄鼠冬眠季节长短的个体差异较大,可以分成深冬眠型、
少冬眠型和不冬眠型三种类型;2)达乌尔黄鼠在冬季表现出深冬眠阵(最低体温Tbm in <20℃ ,冬眠阵的持续时间BD >24 h)、短冬眠阵(Tbmin < 20℃ , BD≤24h)和日眠阵(Tbmin ≥20℃ , BD≤24 h)3 种类型,最低体温分别
为2.54℃ ± 0.35℃ 、10.05℃ ± 1.97℃ 和23.09℃ ± 0.40℃ ,彼此之间差异显著。日眠阵阵间产热阶段的最高体温为38.09℃ ±0.17℃ ,高于深冬眠阵(37.31℃ ±0.15℃ )和短冬眠阵(37.22℃ ±0.31℃ ); 3)深冬眠阵和日
眠阵中最低体温均与环境温度显著相关,冬眠过程中的最低体温为-2.43℃ ;4)深冬眠过程中,多数个体可以短时(≤3 h)耐受- 2℃ ~ 0℃ 的低温,激醒或继续维持深冬眠,无致死效应,但长时间(15 h)或过度低温
(- 5℃ 以下)的条件下,深冬眠的达乌尔黄鼠被激醒(70% )或死亡(30% ),不能持续冬眠; 5)入眠前10 d体温日波动幅度显著增加,高于出眠后的日体温波动,且多数个体入眠前出现体温的“试降”。表明,冬眠前
入眠的准备阶段,动物的体温调节已开始发生变化;冬季日眠的调节机制可能与冬眠不同;短时- 2℃ ~ 0℃ 的体温对深冬眠的达乌尔黄鼠无致死效应。 相似文献
少冬眠型和不冬眠型三种类型;2)达乌尔黄鼠在冬季表现出深冬眠阵(最低体温Tbm in <20℃ ,冬眠阵的持续时间BD >24 h)、短冬眠阵(Tbmin < 20℃ , BD≤24h)和日眠阵(Tbmin ≥20℃ , BD≤24 h)3 种类型,最低体温分别
为2.54℃ ± 0.35℃ 、10.05℃ ± 1.97℃ 和23.09℃ ± 0.40℃ ,彼此之间差异显著。日眠阵阵间产热阶段的最高体温为38.09℃ ±0.17℃ ,高于深冬眠阵(37.31℃ ±0.15℃ )和短冬眠阵(37.22℃ ±0.31℃ ); 3)深冬眠阵和日
眠阵中最低体温均与环境温度显著相关,冬眠过程中的最低体温为-2.43℃ ;4)深冬眠过程中,多数个体可以短时(≤3 h)耐受- 2℃ ~ 0℃ 的低温,激醒或继续维持深冬眠,无致死效应,但长时间(15 h)或过度低温
(- 5℃ 以下)的条件下,深冬眠的达乌尔黄鼠被激醒(70% )或死亡(30% ),不能持续冬眠; 5)入眠前10 d体温日波动幅度显著增加,高于出眠后的日体温波动,且多数个体入眠前出现体温的“试降”。表明,冬眠前
入眠的准备阶段,动物的体温调节已开始发生变化;冬季日眠的调节机制可能与冬眠不同;短时- 2℃ ~ 0℃ 的体温对深冬眠的达乌尔黄鼠无致死效应。 相似文献
70.