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81.
(-)-Epiafzelechin: cyclooxygenase-1 inhibitor and anti-inflammatory agent from aerial parts of Celastrus orbiculatus. 总被引:1,自引:0,他引:1
K R Min B Y Hwang H S Lim B S Kang G J Oh J Lee S H Kang K S Lee J S Ro Y Kim 《Planta medica》1999,65(5):460-462
An inhibitor of cyclooxygenase (COX)-1 activity of prostaglandin H2 synthase was isolated from aerial parts of Celastrus orbiculatus Thunb. (Celastraceae), an oriental folk medicine for rheumatoid arthritis by activity-guided column chromatographic methods. The COX inhibitor was identified as (-)-epiafzelechin, a member of flavan-3-ols by the structural analysis with HR-EI-mass, 1H-NMR and 13C-NMR spectral data. The compound exhibited a dose-dependent inhibition on the COX activity with an IC50 value of 15 microM. (-)-Epiafzelechin exhibited about 3-fold weaker inhibitory potency on the enzyme activity than indomethacin as a positive control. (-)-Epiafzelechin exhibited significant anti-inflammatory activity on carrageenin-induced mouse paw edema when the compound (100 mg/kg) was orally administrated at 1 h before carrageenin treatment. 相似文献
82.
Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans. 相似文献
83.
Lim YH Leem MJ Shin DH Chang HB Hong SW Moon EY Lee DK Yoon SJ Woo WS 《Archives of pharmacal research》1999,22(2):208-212
Activity-guided fractionation of the roots of Anthriscus sylvestris resulted in the isolation and characterization of five cytotoxic compounds, deoxypodophyllotoxin (1), falcarindiol (2), and angeloyl podophyllotoxin (5) from the hexane soluble fraction and morelensin (3), bursehernin (4) from the chloroform soluble fraction. It is the first report of the occurrence of compound 5 in nature. 相似文献
84.
Lim JI 《Current opinion in ophthalmology》1996,7(3):46-50
For the past year, indocyanine green angiography has been applied to evaluation of choroidal neovascularization, pigment epithelial detachment, retinal vascular disorders, and choroidal diseases and tumors. These applications have expanded the potential use of this technique. The relative safety of indocyanine green angiography has contributed to its continued wide-spread application. 相似文献
85.
Dr. Drora Selinger MD Sabina Cohen PhD Anna Schiffmann MD 《Child psychiatry and human development》1978,8(4):239-249
A new approach to teaching Normal Growth and Development to preclinical medical students is described. By using specially constructed multidisciplinary clinical simulations as training and evaluation devices, students were gradually and simultaneously exposed to: (1) subject matter; (2) the concept of multidisciplinary health care delivery; and (3) the objectives, strategies, and techniques of problem solving and diagnostic reasoning that characterize experienced physicians. The course, designed by a child psychiatrist and medical educators, was taught by a multidisciplinary teaching team drawn from faculty and health care representatives. Student evaluations of the course were favorable. 相似文献
86.
Two patients developed persistent ulcers on the trunk after cutaneous surgery. Both had "chemical" diabetes mellitus. Bacteriologic and histopathologic studies of the ulcers were not revealing of cause. The characteristics of the ulcers are described, and are contrasted with typical lesions of pyoderma gangrenosum and Meleney's postoperative progressive synergistic bacterial gangrene. We believe these patients had variant lesions of pyoderma gangrenosum. 相似文献
87.
We report here a patient with acute mycloid leukaemia who relapsed 20 months after undergoing a double autograft procedure in first remission. He was reinduced and subsequently underwent a third autologous bone marrow transplantation in second remission using bone marrow harvested in second remission and a Busulphan and Cyclophosphamide conditioning regimen. Although the engraftment was very slow, he has remained in second remission for 34+ months. This case demonstrates that durable disease-free survival can be attained by a second preparative therapy, even in second remission, for patients relapsed after autologous bone marrow transplantation. 相似文献
88.
Our preliminary studies suggested that the novel gag-truncated mos (tmos) open reading frame (ORF) of R7, a spontaneous deletion mutant of Moloney murine sarcoma virus 124 (MoMuSV124), may be responsible for R7's unique ability to induce brain lesions in all R7-injected mice. However, when we replaced the gag-tmos ORF with either the MoMuSV124 or the homologous myeloproliferative sarcoma virus env-mos gene, we found that both recombinant viruses also induced brain lesions in all injected mice. Although these studies suggested that the critical determinants for brain lesion induction may reside in the tmos sequence common to all three viruses, they did not demonstrate if the N-terminus of Mos was dispensable for this activity. By inserting the FLAG sequence at the 3' end of the R7 gag-tmos ORF, we demonstrated that R7 does synthesize a Gag-tMos fusion protein. Using R7 gag deletion mutants with and without the FLAG sequence, we further demonstrated that (i) deletion of the entire gag sequence abolished R7's transforming activity; (ii) the ability of the virus to transform cultured NIH/3T3 cells was significantly reduced only when most of gag was deleted; (iii) the ability of the virus to induce brain lesions was inversely proportional to the extent of its gag deletions; and (iv) the insertion of FLAG at the Mos C-terminus did not reduce the in vitro transforming activity of the FLAG-tagged viruses but did reduce their ability to induce brain lesions. Thus, we have demonstrated that altering the N- or C-terminus of the R7 Gag-tMos fusion protein can affect disease manifestation. 相似文献
89.
90.
Katherine DeLellis Sabina Rinaldi Rudolph J Kaaks Laurence N Kolonel Brian Henderson Loic Le Marchand 《Cancer epidemiology, biomarkers & prevention》2004,13(9):1444-1451
High circulating concentration of insulin-like growth factor-I (IGF-I) and low circulating concentration of IGF binding protein-3 (IGFBP-3) have been associated with increased risk for breast, prostate, and colorectal cancers. Building on previous work in the Multiethnic Cohort (MEC) showing significant differences in IGF-I levels across racial/ethnic groups, we investigated which lifestyle and dietary factors are associated with levels of IGF-I and IGFBP-3 in a random sample of 1,000 MEC participants, which included Native Hawaiian, African American, Japanese, Latino, and White men and women. Crude analyses confirmed the existence of differences in protein levels with race/ethnicity, sex, age, and body size. Reproductive, physical activity, smoking, and diet variables had less consistent effects. In multivariate analyses, IGF-I levels were lower and IGFBP-3 were higher in females versus males. IGF-I and IGFBP-3 declined with increasing age in both genders. Women in the highest quartile of body mass index showed depressed IGF-I and IGFBP-3 levels; in men, height was significantly positively associated with both proteins. In women, alcohol was directly associated with IGFBP-3. Both proteins were lowest among female Latinos. IGF-I was highest among female African Americans. In men, IGFBP-3 was lowest among African Americans. Overall, although these factors were statistically significant determinants of IGF-related protein levels, they did not explain much of the variation in these levels. A positive correlation was found between IGF-I levels (ng/mL) and colon cancer incidence rates (per 100,000) within the MEC by race/ethnicity for both sexes but not for either breast or prostate cancer. 相似文献