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排序方式: 共有373条查询结果,搜索用时 15 毫秒
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243.
Bonoli M Bendini A Cerretani L Lercker G Toschi TG 《Journal of agricultural and food chemistry》2004,52(23):7026-7032
Capillary electrophoresis (CE) can be effectively used as a fast screening tool to obtain qualitative and semiquantitative information about simple and complex phenolic compounds of extra virgin olive oil. Three simple phenols (tyrosol, hydroxytyrosol, and vanillic acid), a secoiridoid derivative (deacetoxy oleuropein aglycon), and two lignans (pinoresinol and acetoxypinoresinol) were detected as the main compounds in extra virgin olive oils by high-performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE). Spectrophotometric indices, radical scavenging activity, and oxidative stability of extra virgin olive oil samples obtained from olives hand-picked at different ripening degrees were statistically correlated with the CZE and HPLC quantification. The concentration of phenols in extra virgin olive oil decreased with ripeness of olive fruits. The high correlations found between CZE and the other analytical results indicate that CE can be applied as a rapid and reliable tool to routinely determine phenolic compounds in extra virgin olive oils. 相似文献
244.
Baronti Silvia Galassi Elena Ugolini Francesca Miglietta Franco Genesio Lorenzo Vaccari Francesco P. Cacciatori Pierino Gazza Laura 《Genetic Resources and Crop Evolution》2022,69(2):619-633
Genetic Resources and Crop Evolution - Perennial crops are emerging as an effective strategy for adapting to climate change, but also for mitigating net greenhouse gas emissions from agriculture.... 相似文献
245.
1-Aminocyclopentanecarboxylic acid was cleared from cerebrospinal fluid of the cat by a saturable mechanism. Clearance was inhibited by naturally occurring neutral amino acids. Carrier transport may explain the low ratio of amino acid in spinal fluid to that in plasma. 相似文献
246.
Zhang SY Jouanguy E Ugolini S Smahi A Elain G Romero P Segal D Sancho-Shimizu V Lorenzo L Puel A Picard C Chapgier A Plancoulaine S Titeux M Cognet C von Bernuth H Ku CL Casrouge A Zhang XX Barreiro L Leonard J Hamilton C Lebon P Héron B Vallée L Quintana-Murci L Hovnanian A Rozenberg F Vivier E Geissmann F Tardieu M Abel L Casanova JL 《Science (New York, N.Y.)》2007,317(5844):1522-1527
Some Toll and Toll-like receptors (TLRs) provide immunity to experimental infections in animal models, but their contribution to host defense in natural ecosystems is unknown. We report a dominant-negative TLR3 allele in otherwise healthy children with herpes simplex virus 1 (HSV-1) encephalitis. TLR3 is expressed in the central nervous system (CNS), where it is required to control HSV-1, which spreads from the epithelium to the CNS via cranial nerves. TLR3 is also expressed in epithelial and dendritic cells, which apparently use TLR3-independent pathways to prevent further dissemination of HSV-1 and to provide resistance to other pathogens in TLR3-deficient patients. Human TLR3 appears to be redundant in host defense to most microbes but is vital for natural immunity to HSV-1 in the CNS, which suggests that neurotropic viruses have contributed to the evolutionary maintenance of TLR3. 相似文献
247.
The influence of parent and harvest year on the determination of oil, moisture, oleic acid, and linoleic acid contents in intact olive fruit was studied by near-infrared spectroscopy (NIRS). Spectral data from 400 to 1700 nm were recorded on 437 fruit samples collected in 1996 and 1997 from seedling plants derived from three different female parents. Partial least squares models were developed using samples for each year and for each female parent separately and were validated against the other groups. Calibration models were accurate enough to predict all constituents in new samples from a different female parent but were not transferable across years. However, a calibration equation of sufficient accuracy was obtained from the combined data set (r values of 0.94, 0.93, 0.84, and 0.88 and RMSECV values of 1.33, 1.88, 4.73, and 2.91 for oil, moisture, oleic acid, and linoleic acid contents, respectively). These results demonstrate the utility of NIRS as a selection tool in olive breeding programs. 相似文献
248.
Michaud M Martins I Sukkurwala AQ Adjemian S Ma Y Pellegatti P Shen S Kepp O Scoazec M Mignot G Rello-Varona S Tailler M Menger L Vacchelli E Galluzzi L Ghiringhelli F di Virgilio F Zitvogel L Kroemer G 《Science (New York, N.Y.)》2011,334(6062):1573-1577
Antineoplastic chemotherapies are particularly efficient when they elicit immunogenic cell death, thus provoking an anticancer immune response. Here we demonstrate that autophagy, which is often disabled in cancer, is dispensable for chemotherapy-induced cell death but required for its immunogenicity. In response to chemotherapy, autophagy-competent, but not autophagy-deficient, cancers attracted dendritic cells and T lymphocytes into the tumor bed. Suppression of autophagy inhibited the release of adenosine triphosphate (ATP) from dying tumor cells. Conversely, inhibition of extracellular ATP-degrading enzymes increased pericellular ATP in autophagy-deficient tumors, reestablished the recruitment of immune cells, and restored chemotherapeutic responses but only in immunocompetent hosts. Thus, autophagy is essential for the immunogenic release of ATP from dying cells, and increased extracellular ATP concentrations improve the efficacy of antineoplastic chemotherapies when autophagy is disabled. 相似文献
249.
David Lorenzo Juan Fernández-Golfín Manuel Touza Alfonso Lozano 《Wood material science & engineering》2020,15(3):123-129
ABSTRACTThis article shows the performance of spruce bridge that represents the situation of several wooden bridges built in the 1990s in Spain with spruce and fir. In most cases, damages due to severe decay had appeared before 10 years of service life, and the magnitude and extent of the damages were so significant that the substitution of the structures became mandatory. The aim of this study is to understand the causes of early and severe decay, showing the case study of a spruce bridge located in north-west Spain and analysing the influence of wood species, preservative treatments and designs, combined with the variability of environmental conditions in the emergence of early pathological processes. The damage of the elements is related to the wood species used, the impossibility of applying a preservative treatment, the climatic conditions and local climate, bad design details and no maintenance, which result in a prolonged time of wetness during most of the year. This example confirms the inability of spruce wood for being used in exterior structures, such as bridges, which are located in wet and warm climates like north-west Spain and having wood-destroying fungi that can degrade the wooden elements. 相似文献
250.
Valladares F Arrieta S Aranda I Lorenzo D Sánchez-Gómez D Tena D Suárez F Alberto Pardos J 《Tree physiology》2005,25(8):1041-1052
Shade tolerance, plastic phenotypic response to light and sensitivity to photoinhibition were studied in holly (Ilex aquifolium L.) seedlings transported from the field to a greenhouse and in adult trees in the field. All plants were growing in, or originated from, continental Mediterranean sites in central Spain. Seedlings tolerated moderate but not deep shade. Mortality was high and growth reduced in 1% sunlight. Survival was maximal in 12% sunlight and minimal in full sunlight, although the relative growth rate of the seedlings surviving in high light was similar to that of plants in moderate shade. Maximum photochemical efficiency at predawn was significantly lower in sun plants than in shade plants in the field, revealing chronic photoinhibition that was most pronounced in winter. Plasticity in response to available light varied according to the variable studied, being low for photosynthetic capacity and stomatal conductance, and high for specific leaf area, root:shoot ratio and leaf area ratio, particularly in seedlings. Differences in water relations and hydraulic features between sun and shade plants in the field were marginal. High water potential at the turgor loss point of field-grown plants suggested that holly is sensitive to drought during both the seedling and the adult stage. Low relative growth rates in both high and low light with low physiological plasticity in response to light indicate the existence of a stress-tolerance mechanism. We conclude that holly is a facultative understory plant in areas of oceanic and relatively mild climate, but an obligate understory plant in dry continental areas such as the study site. The impact of abandonment of traditional management practices and climate change on these Mediterranean populations is discussed. 相似文献