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61.
AIM:To examine the effects of recombinant human hepatocyte growth factor(rhHGF) and native calf HGF(cHGF) on SMMC-7721 human hepatocellular carcinoma(HCC) cell line. METHODS:Human HCC cell line culture, photometric assay, and flow cytometric assay were used in this study .RESULTS:A similar type of dose-dependent cell growth inhibition effect on SMMC-7721 human HCC cells by rhHGF(5-20 μg/L) as well as by cHGF(25-100 mg/L) had been found, with the maximal effect at the highest concentration used. Approximately over 50% of the cells treated with rhHGF(5 μg/L, 10 μg/L, 20 μg/L) accumulated in the quiescent G0/G1 phase of the cell cycle over incubation periods for 3 d. CONCLUSION:The growth of SMMC-7721 human HCC cells was strongly inhibited by both rhHGF and cHGF. This might be because the cells exposed to HGF became arrested in the G0/G1 phase. 相似文献
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Eiji Tanaka Chihiro Tanaka Atsushi Ishihara Yasumasa Kuwahara Mitsuya Tsuda 《Journal of General Plant Pathology》2003,69(1):1-6
Aciculosporium take (Ascomycota; Clavicipitaceae) is a causal agent of witches' broom of
bamboo plants. The symptoms of this disease are believed to be induced by plant
hormones, particularly auxins. Indole-3-acetic acid (IAA) was identified in
cultures of this fungus in an l-tryptophan-supplemented liquid medium.
IAA production was confirmed on 30 isolates of A. take from various
hosts and locations at levels up to 1 mg/l. The biosynthetic pathway of
IAA in A. take culture was examined by analyzing intermediate products
and by feeding experiments. The results showed that the indole-3-pyruvic acid
pathway (l-tryptophan → indole-3-pyruvic acid → indole
acetaldehyde → IAA) was the dominant pathway in A. take.
Received: June 3, 2002 / Accepted: July 25, 2002 相似文献
64.
Hiromitsu Furuya Tsutomu Matsumoto Shin-ichi Fuji Hideki Naito 《Journal of General Plant Pathology》2003,69(2):115-119
Rice seedling growth, estimated by plant height and root development and discoloration, was better in pasteurized soil than
in unpasteurized soil obtained from a flooded rice field. Rice seedlings also grew better in sterilized soil modified by adding
roots harvested from the pasteurized soil than in soil modified by adding roots harvested from the unpasteurized soil. The
results demonstrate that seedling growth in the rice field soil was inhibited by soil microorganisms, even though no typical
symptoms such as seedling blight or damping-off appeared. Pythium aristosporum is suggested to be involved in the inhibition. Thus, it appears that inconspicuous restraint of rice seedling growth could
occur in soils of rice paddy fields.
Received: May 20, 2002 / Accepted: October 16, 2002
Acknowledgments The authors thank Dr. T. Ichitani, former professor at Osaka Prefectural University, for providing an isolate of Pythium aristosporum for comparison, and Mr. Mitsuaki Sato of Akita Prefectural College of Agriculture for technical assistance. 相似文献
65.
铅、镉和铬在叶类蔬菜中的累积及对其生长的影响 总被引:68,自引:3,他引:68
研究结果表明: 重金属元素铅(Pb) 、镉(Cd) 、铬(Cr) 对几种叶类蔬菜生长和产量都有明显的影响, 且其影响因蔬菜种类、元素种类和浓度的不同而有很大差异, 叶用莴苣> 苋菜> 芥菜> 菜薹>蕹菜, Cr > Cd > Pb ; 不同蔬菜类型可食部位积累重金属元素的顺序为苋菜> 叶用莴苣> 菜薹> 蕹菜> 芥菜;各元素从营养液向蔬菜体内转移的迁移累积率顺序为Cd > Cr > Pb。随着各元素浓度的增大, 对蔬菜生长的影响和其可食部分的富集量随之加大。 相似文献
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69.
Norman Owen-Smith 《Landscape Ecology》2004,19(7):761-771
Large mammalian herbivores are notorious for their propensity towards population irruptions and crashes, yet many herbivore populations remain relatively stable. I explore how resource heterogeneity within landscapes dampens population instability, using a metaphysiological modelling approach considering patch state distributions. Resource heterogeneity is functionally stabilizing through spreading consumption away from preferred resources before these become critically depleted. Lower-quality resources act as a buffer against starvation during critical periods of the seasonal cycle. Enriching resource quality is destabilizing, even if patch diversity is maintained, because food quantity then becomes the limitation. The potential consequences of landscape fragmentation are explored using the Serengeti ecosystem, characterised by broadscale resource gradients, as a hypothetical example. Further insights provided by the model are illustrated with specific examples concerning the effects of patch scales and waterpoint distribution. A metaphysiological modelling approach enables the basic consequences of landscape heterogeneity to be distinguished from further effects that may arise from specific patch scales and configurations, without the distracting detail of spatially explicit models. 相似文献
70.
Judith Hübschen Lilo Kling Ulrike Ipach Volker Zinkernagel Nathalie Bosselut Daniel Esmenjaud Derek J.F. Brown Roy Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(8):779-788
Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry. 相似文献