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81.
82.
W. Y. Chan T. B. Ng Joyce S. Y. Lam Jack H. Wong K. T. Chu P. H. K. Ngai S. K. Lam H. X. Wang 《Applied microbiology and biotechnology》2010,85(4):985-993
Earlier investigations disclose that some plant ribosome-inactivating proteins (RIPs) adversely affect mouse embryonic development.
In the present study, a mushroom RIP, namely lyophyllin from Lyophyllum shimeji, was isolated, partially sequenced, and its translation inhibitory activity determined. Its teratogenicity was studied by
using a technique entailing microinjection and postimplantation whole-embryo culture. It was found that embryonic abnormalities
during the period of organogenesis from E8.5 to E9.5 were induced by lyophyllin at a concentration as low as 50 μg/ml, and
when the lyophyllin concentration was raised, the number of abnormal embryos increased, the final somite number decreased,
and the abnormalities increased in severity. The affected embryonic structures included the cranial neural tube, forelimb
buds, branchial arches, and body axis, while optic and otic placodes were more resistant. Lyophyllin at a concentration higher
than 500 μg/ml also induced forebrain blisters within the cranial mesenchyme. When the abnormal embryos were examined histologically,
an increase of cell death was found to be associated with abnormal structures, indicating that cell death may be one of the
underlying causes of teratogenicity of the mushroom RIP. This constitutes the first report on the teratogenicity of a mushroom
RIP. 相似文献
83.
地方认同视角下居民对农业文化遗产认知及保护态度——以福州茉莉花与茶文化系统为例 总被引:5,自引:0,他引:5
居民对农业文化遗产的认知态度影响其行为选择,并对农业文化遗产的保护及可持续发展具有重要意义。基于人文地理学及环境心理学领域的地方认同理论,选择历史认同、现实认同、情感认同及行为认同4个维度变量,通过问卷调查,以福州居民对全球重要农业文化遗产"福州茉莉花与茶文化系统"的认知及保护态度作为研究对象,并通过构建福州居民农业文化遗产认知及保护规律定量分析居民认知态度、保护行为与人口特征之间的关系。结果表明:(1)福州居民对茉莉花与茶文化系统的行为认同维度得分高于其他维度,且福州市民各维度得分均高于外来居民;(2)受访居民对农业文化遗产的地方认同与其年龄、受教育水平、收入水平及在福州居住时间长短的关系较为密切;(3)通过构建福州居民农业文化遗产认知及保护规律发现,福州居民对农业文化遗产的保护行为主要受其对该遗产项目认知态度的影响,与居民人口特征相关性较弱。拓展农业文化遗产领域的研究视角及方法,促进农业文化遗产地动态保护与可持续发展具有参考价值。 相似文献
84.
Wong L 《Briefings in bioinformatics》2002,3(4):389-404
The process of building a new database relevant to some field of study in biomedicine involves transforming, integrating and cleansing multiple data sources, as well as adding new material and annotations. This paper reviews some of the requirements of a general solution to this data integration problem. Several representative technologies and approaches to data integration in biomedicine are surveyed. Then some interesting features that separate the more general data integration technologies from the more specialised ones are highlighted. 相似文献
85.
Characterization of humoral responses in mice immunized with plasmid DNAs encoding SARS-CoV spike gene fragments 总被引:11,自引:0,他引:11
Zeng F Chow KY Hon CC Law KM Yip CW Chan KH Peiris JS Leung FC 《Biochemical and biophysical research communications》2004,315(4):1134-1139
The immunological characteristics of SARS-CoV spike protein were investigated by administering mice with plasmids encoding various S gene fragments. We showed that the secreting forms of S1, S2 subunits and the N-terminus of S1 subunit (residues 18-495) were capable of eliciting SARS-CoV specific antibodies and the region immediate to N-terminus of matured S1 protein contained an important immunogenic determinant for elicitation of SARS-CoV specific antibodies. In addition, mice immunized with plasmids encoding S1 fragment developed a Th1-mediated antibody isotype switching. Another interesting finding was that mouse antibodies elicited separately by plasmids encoding S1 and S2 subunits cooperatively neutralized SARS-CoV but neither the S1 nor S2 specific antibodies did, suggesting the possible role of both S1 and S2 subunits in host cell docking and entry. These results provide insights into understanding the immunological characteristics of spike protein and the development of subunit vaccines against SARS-CoV. 相似文献
86.
A differential medium for the identification of races 1 and 4 of Fusarium oxysporum f.sp. cubense 总被引:1,自引:0,他引:1
W.C. Wong 《Letters in applied microbiology》1988,6(3):51-54
Three distinctive colony types were produced when Fusarium oxysporum f.sp. cubense (Foc ) races 1 and 4 were cultured on a defined basal medium containing an appropriate carbon source and bromothymol blue as a pH indicator. These distinctive cultural characteristics have been used as a specific and reliable method for the differentiation of races 1 and 4 of Foc from other species of Fusarium. 相似文献
87.
Detection by high pressure infrared spectrometry of hydrogen-bonding between water and triacetyl glycerol 总被引:3,自引:0,他引:3
E C Mushayakarara P T Wong H H Mantsch 《Biochemical and biophysical research communications》1986,134(1):140-145
The barotropic behavior of neat and aqueous 1,2,3-triacetyl glycerol was investigated by FT-IR spectroscopy over the pressure range 0.001 to 35 kbar. The infrared spectrum in the presence of water shows bands characteristic of hydrogen bonded carbonyl groups. An increase in hydrostatic pressure leads to a strengthening of the intermolecular hydrogen bond between water and the lipid ester C = O groups. The pressure-induced formation of ice VI at 9 kbar does not affect this hydrogen bond, however, the formation, at 20 kbar, of ice VII in which the water/water hydrogen bonds are stronger than the lipid C = O/water hydrogen bonds, frees the lipid carbonyl groups from the hydrogen-bonding to water. 相似文献
88.
Silin Wu Ye Gu Yuying Huang Tyh-Chai Wong Hailin Ding Tengfei Liu Yu Zhang Xiaobiao Zhang 《Biochemical genetics》2017,55(3):253-267
The microRNAs (miRNAs) are involved in multiple pathological processes among various types of tumors. However, the functions of miRNAs in benign brain tumors are largely unexplored. In order to explore the pathogenesis of the invasiveness in non-functional pituitary adenoma (NFPA), the miRNAs expression profile was analyzed between invasive and non-invasive non-functional pituitary adenoma by miRNAs microarray. Six most significant differentially expressed miRNAs were identified including four upregulated miRNAs hsa-miR-181b-5p, hsa-miR-181d, hsa-miR-191-3p, and hsa-miR-598 and two downregulated miRNAs hsa-miR-3676-5p and hsa-miR-383. The functions and corresponding signaling pathways of differentially expressed miRNAs were investigated by bioinformatics techniques, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The result of GO analysis indicates regulation of voltage-gated potassium channel activity, positive regulation of sodium ion transport, positive regulation of GTPase activity, negative regulation of Notch signaling pathway, etc. KEGG pathway reveals a series of biological processes, including prolactin signaling pathway, endocrine and other factor-regulated calcium reabsorption, fatty acid metabolism, neuroactive ligand-receptor interaction, etc. The miRNAs hsa-miR-181a-5p was verified by quantitative real-time PCR, and the expression level was in accordance with the microarray result. Our result can provide the evidence on featured miRNAs which play a prominent role in pituitary adenoma as effective biomarkers and therapeutic targets in the future. 相似文献
89.
以植物钾离子外排通道(K’channeloutward.rectifier,KCO)基因为研究对象,运用CodonW软件分析了75个植物KCO基因密码子的使用模式,探讨密码子的使用模式和影响密码子使用的各种可能因素。结果表明:碱基组成差异(r=0.961,P〈0.01)和自然选择(r=0.568,P〈0.01)是影响密码子使用的主要因素,并且高表达的基因强烈偏爱使用以G或C结尾的密码子。确定了UUC、CUC等26个均以G/C结尾的密码子为植物KcD基因的高表达优越密码子。 相似文献
90.
ATP-dependent oxalate facilitated calcium transport in sarcoplasmic reticulum (SR) preparations obtained from rabbit vastus lateralis muscle (fast skeletal muscle; Fsr) and soleus (slow skeletal muscle; Ssr) was determined. Addition of exogenous calmodulin did not stimulate calcium transport in either Fsr or Ssr preparations. Fsr and Ssr previously washed in 1 mM EGTA demonstrated a reduced capacity to transport Ca2+; the exogenous addition of calmodulin (0.24 μM) under these conditions, did not restore uptake activity but significantly decreased the steady-state level of Ca2+ uptake. Extracts of skeletal SR prepared by treatment with 0.2 mM EDTA and boiling produced significantly more stimulation of red cell Ca2+ATPase activity than extracts prepared by boiling alone. This stimulation of red cell Ca2+-ATPase was inhibited to a significant extent by , a known anti-calmodulin agent. Radioimmunoassay revealed that extracts prepared by boiling or EDTA-treatment followed by boiling contained considerable amounts of calmodulin. Washing with 1 mM EGTA, though, did not release any calmodulin from SR. These studies reveal that calmodulin is present in both Fsr and Ssr and can only be removed by harsh treatments. The role of calmodulin in skeletal muscle Ca2+-transport remains to be determined. 相似文献