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891.
892.
Celastraceae species have a long tradition of use in folk medicine and agriculture. Intensive research into this family has resulted in the isolation of a large number of secondary metabolites with a wide range of bioactivity, with the most characteristic being the dihydro-β-agarofuran sesquiterpenes and the quinomethide triterpenoids. Despite diterpenoids not often being found in Celastraceae species, the novelty of their structures and their biological activities has stimulated their research. There are several reviews covering studies on Tripterigium wilfordii, a traditional Chinese medicine, and their metabolites, but none focusing on bioactive diterpenoids isolated from other Celastraceae species. This review focuses on diterpenes isolated from Celastraceae species, and their skeleton diversity, species sources, and tested biological activities are discussed. The literature from January 2000 to October 2016 is reviewed, and 64 references are cited. A total of 118 isolated diterpenoids possessing twelve different skeletons are included and classified by the following tested biological activity: cytotoxicity, anti-inflammatory, antitumour-promotion, anti-HIV, immunosuppressant, reversal multi-drug resistance, and antifeedant. This compliance information will be helpful in further research into diterpene Celastraceae isolation, biological activity determination and structure specific modifications. 相似文献
893.
Violeta Lorén Josep Manyé Mari C. Fuentes Eduard Cabré Isabel Ojanguren Jordi Espadaler 《Probiotics and antimicrobial proteins》2017,9(1):71-80
Use of probiotic therapy is an active area of investigation to treat intestinal disorders. The clinical benefits of the I3.1 probiotic formula (Lactobacillus plantarum (CECT7484, CECT7485) and P. acidilactici (CECT7483)) were demonstrated in irritable bowel syndrome (IBS) patients in a randomized, double-blind, placebo-controlled clinical trial. The aim of this study was to evaluate the therapeutic effects of I3.1 in two experimental models of colitis, a dextran sulfate sodium (DSS)-induced colitis model and an interleukin (IL)-10-deficient mice model. Colitis was induced in 32 8-week-old Balb/c mice by administering 3% (w/v) DSS in drinking water for 5 days. Probiotics were administered orally (I3.1 or VSL#3, 1 × 109 CFU daily) for 10 days before the administration of DSS. Also, probiotics (I3.1 or VSL#3, 1 × 109 CFU daily) were administered orally to 36 6-week-old C57B6J IL-10(?/?) mice for 10 weeks. Body weight was recorded daily. Colon samples were harvested for histological examination and cytokine measurements. Body weight after DSS administration did not change in the I3.1 group, whereas the VSL#3 group had weight loss. Also, I3.1 normalized IL-6 to levels similar to that of healthy controls and significantly increased the reparative histologic score. In the IL-10-deficient model, both VSL#3 and I3.1 reduced the severity of colitis compared to untreated controls, and I3.1 significantly reduced the levels of IFN-γ compared to the other two groups. In conclusion, I3.1 displays a protective effect on two murine models of experimental colitis. Results suggest that the mechanism of action could be different from VSL#3. 相似文献
894.
Spectral attenuation of brain and retina tissues in the near‐infrared range measured using a fiber‐based supercontinuum device 下载免费PDF全文
José Eduardo Saldaña‐Díaz Sebastián Jarabo Francisco Javier Salgado‐Remacha Lorena Perdices Isabel Pinilla Ana Sánchez‐Cano 《Journal of biophotonics》2017,10(9):1105-1109
A novel setup for the efficient constant optical measurements of biological tissues in the near infrared is presented. The system combines the use of a fiber‐based supercontinuum source with a simple optics fiber collimator. This configuration allows a wide spectral range of measurement and, at the same time, can efficiently filter the straightforward transmitted light while avoiding scattered light. As a performance example, the optical characterization of rat brain and retina tissues are shown. The attenuation coefficient for both tissues in the near infrared region is also obtained. This technique could be applied in clinical research as a noninvasive method with several potential practical applications. 相似文献
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896.
Eudald Carbonell Isabel Sauceda Ángel Carbajo Isabel Díaz Francisco J. García Marcos García Juan Gil Luz M. León Eva Mancha Rosa M. Merino Abel Morcillo Antonio Rodríguez Santiago Giralt 《L'Anthropologie》2005,109(2):267
The excavations carried out in the cave of Santa Ana (Cáceres, Spain), cave of the karstic network of the “Calerizo” of Cáceres, enabled us to know the existence, in stratigraphy, of the three lito-techniques modes which characterize the industrial development of lower and middle Pleistocene in the Iberian Peninsula. On standby of new research, the results obtained until now permit us two work out a diachronic assumption of technical evolution. In the Iberian Peninsula, there are only two karstic systems where we can fallow this technological development; one is the “Sierra de Atapuerca” (Burgos) and the other is the “Calerizo de Cáceres” (Cáceres). 相似文献
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898.
Several pentahalophenylplatinate complexes with Pt-Sn metal-metal bonds have been synthesized by facile insertion of SnCl2 into Pt-Cl bonds of the starting platinum substrates. The complexes have been characterized spectroscopically and, in the case of (NBu4)2[trans-Pt(SnCl3)2(C6F5)2] and (NBu4)2[trans-Pt2(μ-Cl)2(SnCl3)2(C6F5)2], the structures have been analyzed by X-ray diffraction. The reactivity of these derivatives towards neutral ligands has been explored. The electronic spectra of some selected derivatives have also been examined. 相似文献
899.
Proteins Encoded by Sphingomonas elodea ATCC 31461 rmlA and ugpG Genes, Involved in Gellan Gum Biosynthesis, Exhibit both dTDP- and UDP-Glucose Pyrophosphorylase Activities 下载免费PDF全文
900.