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排序方式: 共有414条查询结果,搜索用时 31 毫秒
201.
Wu TF Hsu CY Huang HS Chou SP Wu H 《Journal of agricultural and food chemistry》2007,55(24):9784-9791
Pycnogenol, polyphenolic compounds extracted from the pine bark, is beneficial for human health. To understand more of its effects, the present study is to explore the protein expression pattern induced by pycnogenol in RAW 264.7 cells. Global analysis using two-dimensional gel electrophoresis indicated that treatment with pycnogenol induces upregulation of four proteins, whose identities were revealed by mass spectrometry as cathepsin D, keratinocyte lipid-binding protein, proteasome subunit alpha type 1, and annexin IV. The pycnogenol effect displayed a time- and concentration-dependent manner. Unlike pycnogenol, N-acetyl cysteine and vitamin C had no effect on cathepsin D expression. Further studies showed that cathepsin D induction is correlated with an increase of lysosomal staining and enhancement of phagocytosis. These results reveal the novel effects of pycnogenol on protein expression and phagocytic functions and illustrate the advantage of proteomics-based strategy in unveiling the molecular basis of phytochemicals. 相似文献
202.
203.
Kessler JD Kahle KT Sun T Meerbrey KL Schlabach MR Schmitt EM Skinner SO Xu Q Li MZ Hartman ZC Rao M Yu P Dominguez-Vidana R Liang AC Solimini NL Bernardi RJ Yu B Hsu T Golding I Luo J Osborne CK Creighton CJ Hilsenbeck SG Schiff R Shaw CA Elledge SJ Westbrook TF 《Science (New York, N.Y.)》2012,335(6066):348-353
204.
Fast turnaround multiresidue screen for pesticides in produce. 总被引:2,自引:0,他引:2
J P Hsu H J Schattenberg M M Garza 《Journal of the Association of Official Analytical Chemists》1991,74(5):886-892
A rapid multiresidue screen for 110 pesticides was applied to 5628 produce samples. Samples were extracted, analyzed, and evaluated within 6 1/2 h of receipt. Analyses were confirmed within a 24 h period on those samples in which a potential residue was found above the U.S. Environmental Protection Agency's tolerance level. A thorough yet quick chromatographic interpretation program is also described. 相似文献
205.
Chin-Fei Hsu 《Water, air, and soil pollution》1986,30(1-2):295-302
The National Atmospheric Deposition Program (NADP) and National Trends Network (NTN) have been gathering data to estimate mean deposition of various constituents of precipitation over areas of varying size and time periods of varying length. The mean values are estimated mainly by sampling at various locations and at discrete times. Such estimations introduce uncertainty about the means since the samplers represent only a minute fraction of the total area to be estimated. When two or more such means are compared, some estimation of uncertainties is required to derive the statistical significance. This paper examines two methods capable of estimating such uncertainty —areal-temporal correlation and kriging approaches. These methods are applied to the NADP/NTN data, and the estimated uncertainties are compared for concentrations of nine constituents, plus conductivity and pH of the rainfall. The estimated root mean square errors (RMSE) of both methods are smaller than the non-weighted standard deviation. The RMSE of the correlation approach is smaller than that of kriging for K, NH4, N03, pH, and precipitation volume for the 3 U.S. sub-regions. Mixed results occur for other ions. 相似文献
206.
Shih HD Liu YC Hsu FL Mulabagal V Dodda R Huang JW 《Journal of agricultural and food chemistry》2003,51(1):95-99
Streptomyces padanus strain PMS-702 is an antagonist of Rhizoctonia solani AG-4, the causal agent of damping-off of cabbage. Treatment of cabbage seeds with the culture filtrate of S. padanus strain PMS-702 was effective in reducing the incidence of damping-off of cabbage. The major active ingredient from the culture filtrate of S. padanus strain PMS-702 was purified by silica gel column chromatography and identified as the polyene macrolide, fungichromin, by NMR and mass spectral data. Bioassay studies showed that fungichromin had a strong antifungal activity against R. solani AG-4, and its minimum inhibitory concentration (over 90% inhibition) was found to be 72 microg/mL. This is the first report of fungichromin from S. padanus as an active ingredient for the control of Rhizoctonia damping-off of cabbage. 相似文献
207.
Mycelia from Antrodia camphorata in Submerged culture induce apoptosis of human hepatoma HepG2 cells possibly through regulation of Fas pathway 总被引:2,自引:0,他引:2
The objective of this study was to investigate the antiproliferative effect and the mechanism of the methanol extracts of mycelia (MEM) form Antrodia camphorata in submerged culture toward HepG2 cells. The results showed that MEM-induced cell apoptosis involved up-regulation of Fas and down-regulation of Bcl-2, DR3, DR4, TNFRI, and TNFRII in HepG2 cells, while no changes on the levels of Bax, Bid, Bad, and Bak protein were observed. On the basis of these results, the involvement of the Fas/Fas ligand (FasL) death-receptor pathway, in MEM-induced apoptosis in HepG2 cells, was investigated. The apoptosis inducing activity was significantly enhanced by a Fas activator and inhibited by a Fas antagonist. To know about the effect of MEM on the activation of the apoptotic pathway, the adenovirus transfected with Bcl-2 was infected on HepG2 cells. The data showed that the percentage of apoptotic cells induced by MEM in Bcl-2-infected HepG2 (Bcl-2 overexpression) was not significantly different from that of uninfected HepG2. These results demonstrate that MEM induces HepG2 apoptosis through inhibition of cell growth and up-regulation of Fas/FasL to activate the pathway of caspase-3 and -8 cascades. 相似文献
208.
209.
Bovine ephemeral fever (BEF) is a vector-borne disease of cattle, spanning tropical and subtropical zones of Asia, Australia, and Africa, caused by Ephemerovirus of the Rhabdoviridae. Taiwan has had 3 BEF epizootics, occurring in 1989, 1996, and 1999, since the vaccination regimen was initiated in 1984, given once a year in the spring with a single-dose formaldehyde-inactivated vaccine using the 1983 isolate as the seed virus. This study evaluated the 1999 population immunity against BEF virus in Taiwanese dairy cows with a neutralization test and whether the recent BEF virus isolates have mutated significantly from the vaccine virus. In March 1999, before vaccination, 94% of the animals studied were already seropositive, suggestive of an endemic or persistent infection from the previous year. By June 1999, when 51% of herds had been vaccinated, the antibody level rose, and by September 1999, the serum-neutralizing antibody (SNA) level fell to a minimum, preceding the outbreak of BEF in October 1999, during which the antibody levels of vaccinated cows continued to decline while those of unvaccinated cows rose sharply. The results suggest that, in 1999, vaccine-induced immunity was partially protective against BEE Because the current single-dose vaccination regimen resulted in minimal population immunity by September, a booster vaccination given in late summer may be advisable for future disease control. Analysis of the glycoprotein gene of Taiwanese isolates between 1983 and 1999 showed a 97.4-99.6% homology, with an alteration of 4 amino acids in antigenic sites G1, G3b, and G3c. Phylogenetic analysis of Taiwanese isolates revealed at least 2 distinct clusters: the 1983-1989 isolates and the 1996-1999 isolates. Both were distinct from 2 Japanese strains and the Australian BB7721 strain. Thus, at least 2 distinct BEF viruses, which had diverged before 1983, existed in Taiwanese dairy cows. 相似文献
210.