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91.
目的:对一叶萩枝叶的化学成分进行研究。方法:应用各种色谱技术从一叶萩总碱部位中分离化合物,根据理化常数和波谱(NMR及MS等)分析方法对化合物的结构进行鉴定。结果:自一叶萩枝叶的总碱部位中分离得到11个化合物。分别鉴定为:(-)-15β-ethoxy-14,15-dihvdroviroallosecurinine(1),一叶萩碱(securinine,2),二氢一叶萩碱(14,15-dihydrosecurinine,3),4-epiph),llanthine(4),securitinine(5),右旋别一叶萩碱(viroallosecurinine,6),一叶萩醇A(securinol A,7),secu’amamineA(8),ent-phyllanthidine(9),(+)-aquilegiohde(10)和(+)-menisdaurilide(11)。结论:1为新化合物,4,8,10和11为首次从一叶萩中分离得到。 相似文献
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Kieffer N Schmitz M Plançon S Margue C Huselstein F Grignard G Dippel W Nathan M Giacchi S Scheiden R 《International journal of oncology》2005,26(6):1549-1558
A major technical challenge related to gene expression profiling of tissue samples is the difficulty of procuring selected cell populations from tissues that by nature are heterogeneous, such as prostate tissue. In this study we have examined the expression of integrin-linked kinase (ILK) mRNA in prostate adenocarcinoma cells versus normal prostate epithelial cells in order to determine whether ILK could be used as a reference marker gene for prostate adenocarcinoma cell mRNA isolation. Using laser microdissection (LMD) technology and real-time PCR, together with immunohistochemistry, we have analyzed ILK mRNA expression in epithelial cells isolated from frozen prostate biopsy specimens as well as 4 prostate cell lines (RWPE-1, LNCaP, PC-3 and DU 145) and correlated ILK mRNA expression with ILK protein expression. We demonstrate that quantitative upregulation of ILK mRNA expression in prostate epithelial cells derived from prostate tissue correlated with ILK protein expression and with the histopathology diagnosis of prostate adenocarcinoma. We further show that the level of ILK overexpression was directly influenced by the method used to isolate prostate adenocarcinoma cells (bulk tissue versus LMD dissected cells). These data provide evidence that ILK mRNA is quantitatively upregulated in prostate adenocarcinoma cells versus normal epithelial cells and is therefore a useful internal reference gene marker to evaluate the quality of prostate adenocarcinoma cell derived mRNA used for large scale prostate cancer cDNA gene profiling. 相似文献
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Reichert F Barak V Tarshis M Prindull G Tarshis E Ben-Ishay Z 《European journal of haematology》2005,75(1):41-46
Reducing the blood supply of tumors is one modality to combat cancer. The objective of this study was to evaluate such an approach in the treatment of localized murine AML (acute myelogenous leukemia). For this purpose we designed an experimental model in which leukemic cells were embedded in 1% agar discs before subcutaneous implantation in C57Bl female mice. The C-1498 AML cell line (Frederick Inst., NCI, MD, USA) was used. Thirty experimental mice received on alternate days injections of 5 x 2.5 microg anti-VEGF (vascular endothelial growth factor) and 5 x 2.5 microg anti-Flk-1 (VEGFR2) antibodies to the site of cell implantation over a period of 10 d. Fifteen control mice received daily PBS injections. All mice were sacrificed 16 d after AML implantation. Of the 30 experimental animals, macroscopic examination showed in 21 animals (70%) small sized, pale tumors (0.5 g); in six mice (20%) the tumors were replaced completely by necrotic tissue, while in three mice (10%), there were large (2.5 g), highly vascularized tumors. In all 15 control mice large highly vascularized tumors were seen. A separate group of mice was studied for total survival following AML implantation. While 12 mice in the control group not treated with antibodies survived for 16 d post-implantation, survival was prolonged in 15 antibody treated mice by approximate 30 d to a total survival time of 48 d. Tumor specimens were processed for histology, immunohistochemistry (IHC) for CD31 endothelial cell antigen, and tube-like formation assay. The small, pale tumors of antibody treated animals consisted of degenerate hyaline material with remnant nests of leukemic cells, whereas large tumors showed sheets of leukemic cells and numerous blood vessels. Specimens processed for CD31 antigen showed scarce or absence of blood vessels in the small, pale tumors in contrast to intensive staining from a rich network of blood vessels in the large, highly vascularized tumors. Tube-like formation assays disclosed rudimentary Grade 1 endothelial cell tubes in the small, pale tumors as opposed to polygonal Grade 4 tube formation in control animals. In conclusion, this murine model of localized AML allows assessment of anti-angiogenic tumor regression. Anti-angiogenic antibodies against VEGF and Flk-1 have therapeutic effects in murine AML. 相似文献
96.
The copepod Naobranchia lizae (Kroyer, 1863) and the monogenean Metamicrocotyla macracantha (Alexander, 1954; Koratha, 1955) are gill parasites found on the striped mullet (Mugil cephalus) in the Charleston Harbor Estuarine System (South Carolina, USA). Branchial distribution of each species was studied in mono- and bispecific conditions. No preference for the right or left side of the fish host was observed for either species in either condition. Both species exhibited heterogeneous distribution among the gill arches, with a preference for arch I. N. lizae exhibited intraspecific competition and a saturation threshold in both mono- and bispecific conditions. A shift in niche toward the posterior arches was observed for M. macracantha only in bispecific infection. Interspecific competition was detected exclusively on the posterior arches, where M. macracantha seemed out-competed by N. lizae. The data indicated that both neutral and negative interactions played a role in determining the distribution of N. lizae and M. macracantha individuals on the gill arches of M. cephalus. 相似文献
97.
We retrospectively investigated the outcome of 30 newly diagnosed patients with mantle cell lymphoma treated with high-dose therapy and autologous stem cell transplantation in first response. With a median follow-up of 55 months, the 5-year overall-survival is 62%, the 5-year progression-free-survival is 40% and no secondary malignancy has occurred. 相似文献
98.
Effects of armagnac or vodka on platelet aggregation in healthy volunteers: a randomized controlled clinical trial 总被引:1,自引:0,他引:1
Umar A Depont F Jacquet A Lignot S Segur MC Boisseau M Bégaud B Moore N 《Thrombosis research》2005,115(1-2):31-37
BACKGROUND: Cardiovascular mortality is especially low in southwest France (the French Paradox). In previous experimental studies, we found that alcohol-free extracts of armagnac could inhibit human platelet function in vitro and experimental thrombosis in vivo. To test the possible relevance of these findings, we tested the effects of daily use of small quantities of armagnac against same alcohol strength, polyphenol-free vodka in healthy volunteers. METHOD: Randomized controlled trial comparing 5-year old armagnac (30 ml/day for 2 weeks) to same alcoholic strength vodka, in 20 healthy volunteers, on platelet aggregation induced by ADP, collagen, and thrombin, as well as bleeding time, partial thromboplastin time (pTT), and plasma lipids during and after consumption. Platelet testing was done blind. RESULTS: After 14 days, ADP-induced platelet aggregation was inhibited more in armagnac (-31+/-3.2% compared to pretreatment values, p<.01) than in vodka (-11.0+/-6.8%, NS) users (p<.05, armagnac vs. vodka). A rebound increase of aggregation was found 2 weeks later in vodka but not in armagnac users. The same pattern was found for thrombin-induced aggregation, including post-treatment rebound. No effect was found on collagen-induced aggregation, bleeding time, pTT, or plasma lipids. CONCLUSION: The chronic ingestion of moderate quantities of armagnac modified platelet aggregation to ADP in healthy volunteers. The difference with the effects of same alcohol degree vodka is in favour of an effect of the nonalcoholic fraction in the effects of armagnac, rather than just alcohol. All spirits may not be equal for cardioprotection. 相似文献
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