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11.
Taiwania (Taiwania cryptomerioides Hayata), native to Taiwan, is one of the most economically important tree species grown there. In this article we summarize
the current results of phytochemistry and bioactivity of Taiwania extracts, including antifungal, antitermite, antibacterial,
and antimite activities as well as cytotoxicity against three tumor cells. The resources of Taiwania are also addressed.
Received: January 23, 2002 / Accepted: March 8, 2002
Acknowledgment The authors thank the National Science Council of R.O.C. for financial support (NSC-90-2313-B-002-344).
Correspondence to:S.-T. Chang 相似文献
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S. L. Hsieh H. T. Chang C. H. Wu C. M. Kuo 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):527-546
The stearoyl-CoA desaturase cDNA in tilapia (Oreochromis mossambicus) was cloned by RT-PCR and RACE, and it was compared with those in grass carp, common carp and milkfish. Nucleotide sequence analysis revealed that the full length of cDNA (1172 bp) clone encompasses 1008 bp open reading frame (ORF) encoding 336 amino acid residues. The deduced amino acid sequence shares 78–82% identity with the teleosts and 64–66% with mammals compared, and like these fish, the cloned tilapia stearoyl-CoA desaturase amino acid sequence conserves three histidine cluster motifs (one HXXXXH and two HXXHH), which functioned as non-heme iron binding sites, essential for stearoyl-CoA desaturase activity. RT-PCR and Northern blot analysis reveal that tilapia stearoyl-CoA desaturase is expressed only in liver, but the stearoyl-CoA desaturase expression in multiple tissues was observed in milkfish, grass carp and carp. Further, the hormonal regulation of stearoyl-CoA desaturase gene expression was investigated by a single injection of 17β-estradiol and testosterone. The results showed that the administration of 17β-estradiol to tilapia led to a greater increase in desaturase activity than testosterone, and higher doses of steroids produced greater increases in enzyme activity. The comparative RT-PCR analysis showed that the stearoyl-CoA desaturase mRNA level increased significantly in 17β-estradiol treated animals, especially in the groups receiving a single injection of 50 mg 17β-estradiol. This was reflected in the decrease in the saturated fatty acids and the increase in the monounsaturated fatty acids. The proportion of the polyunsaturated fatty acids was not affected. 相似文献
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The CpG motif within bacterial DNA is a potent immuno-stimulatory moiety. Here, using a 2-D electrophoretic approach, we investigated the effect of synthetic oligodeoxynucleotide containing a B type CpG motif (CpG-B ODN) on the protein expression profile of swine peripheral blood mononuclear cells (PBMC). We found that several proteins including spondin 1, N-acetolactate alpha linked acidic dipeptidase; V kappa light chain, T cell receptor variable alpha chain, heat shock protein (Hsp) 60, Hsp70, KIAA0857 protein, and PNAS-146 were up-regulated in PBMC by CpG-B ODN stimulation. Further studies showed that CpG-B ODN-mediated Hsp60, Hsp70 and Hsp90 expressions were closely associated with the TLR9 signalling pathway. Pretreatment with inhibitors of Hsp70, Hsp90 and TLR9 all blocked the CpG-B ODN-mediated anti-apoptotic effect in swine PBMC. These results suggest that CpG-B ODN treatment of swine PBMC may enhance the expression of biologically active proteins, notably spondin 1, V kappa light chain, T cell receptor variable alpha chain and Hsps, which may play an important role in CpG-B ODN-mediated activation of immune responses and enhancement of swine PBMC survival. 相似文献
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病毒病对番茄生产造成严重危害, 近年来在番茄种植新区发生严重, 疑似为种子带毒传播。本研究通过对云南省怒江州番茄种植新区的番茄病毒病样品采用RNA-seq高通量测序, RT-PCR验证的方法检测病毒种类;对番茄病果种子进行超薄切片制样透射电子显微镜观察, 将病果种子播种后对种苗进行RT-PCR带毒检测。结果表明, RNA-seq高通量测序及RT-PCR检测到的病毒有番茄环纹斑点病毒(tomato zonate spot orthotospovirus, TZSV)、番茄黄斑驳相关病毒(tomato yellow mottle-associated virus, TYMaV)、辣椒脉斑驳病毒(chili veinal mottle virus, ChiVMV)、南方番茄病毒(southern tomato virus, STV)。透射电镜观察到种胚细胞及胚乳细胞中分布典型的正番茄斑萎病毒属Orthotospovirus病毒粒体。病果种子播种28 d后的种苗具有病毒病症状, 通过RT-PCR检出TZSV、ChiVMV、STV, 检出率分别为60%、100%、80%。上述研究结果为TZSV通过种子传播提供了有利的证据, 并为源头防控番茄病毒病提供了依据。 相似文献
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Tien‐Chun Wan Yu‐Tse Liu Lan‐Tyi Duann Kuo‐Hui Yu Chih‐Ming Chen Liang‐Chuan Lin Ryoichi Sakata 《Animal Science Journal》2014,85(1):75-80
The purposes of this study were to assess the improvement of fatty liver induced by ethanol with animal liver and bile extracts. This research aimed to increase the economic values of animal liver and bile extracts and used these to reduce damage of ethanol‐induced fatty liver. Extracts came from animal liver and bile, including pig bile powder, pig liver extract, a mixture of pig bile powder and pig liver extract, chicken bile powder, chicken liver extract, and a mixture of chicken bile powder and chicken liver extract, and these were fed to Long‐Evans rats. The results showed that rats fed ethanol for long terms could increase values of aspartate transaminase, cholesterol, γ‐glutamy‐transferase and alkaline phosphatase. Pig bile powder could decrease the values of aspartate transaminase, cholesterol and γ‐glutamy‐transferase. The significances also decreased on aspartate transaminase, γ‐glutamy‐transferase and aspartate transaminase, which were carried out with the pig liver extract treatment. These results suggest pig bile and liver extracts have high potential to improve rats' ethanol‐induced fatty liver with serum biochemical parameters. 相似文献
20.
Bo Qi Zhengkai Yuan Shaorong Lu Kuo Liu Shanrong Li Liping Yang Jinhong Yu 《Fibers and Polymers》2014,15(2):326-333
The graphene oxide (GO) sheets are chemically grafted with γ-etheroxygentrimethoxysilane (KH560) and liquid crystalline epoxy (LCE) is synthesized from 4,4′-bis(2-hydroxyhexoxy)biphenyl (BP2) and epichlorohydrin before being incorporated into epoxy matrix. Then we present a novel approach to the fabrication of advanced polymer composites from epoxy matrix by incorporation of two modifiers, which are grafted GO (g-GO) and LCE. The mechanical properties of epoxy composites are greatly improved by incorporating LCE/g-GO hybrid fillers. For instance, the addition of 3 wt% hybrid filler (2 wt% g-GO and 1 wt% LCE) into the epoxy matrix resulted in the increases in impact strength by 132.6 %, tensile strength by 27.6 % and flexural strength by 37.5 %. Moreover, LCE/g-GO hybrid fillers are effective to increase thermal decomposition temperature, glass transition temperature, and storage modulus by strong affinity between the fillers and epoxy matrix. 相似文献