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排序方式: 共有350条查询结果,搜索用时 31 毫秒
341.
Toncian T Borghesi M Fuchs J d'Humières E Antici P Audebert P Brambrink E Cecchetti CA Pipahl A Romagnani L Willi O 《Science (New York, N.Y.)》2006,312(5772):410-413
We present a technique for simultaneous focusing and energy selection of high-current, mega-electron volt proton beams with the use of radial, transient electric fields (10(7) to 10(10) volts per meter) triggered on the inner walls of a hollow microcylinder by an intense subpicosecond laser pulse. Because of the transient nature of the focusing fields, the proposed method allows selection of a desired range out of the spectrum of the polyenergetic proton beam. This technique addresses current drawbacks of laser-accelerated proton beams, such as their broad spectrum and divergence at the source. 相似文献
342.
Bruni R Rossi D Muzzoli M Romagnoli C Paganetto G Besco E Choquecillo F Peralta K Lora WS Sacchetti G 《Fitoterapia》2006,77(7-8):538-545
The hydroalcoholic extract of Maytenus krukovii bark was investigated for its in vitro mutageno-protective activities by means of the Ames Salmonella/microsome assay. The extract showed an inhibitory effect in both T98 and T100 strains against the mutagenic activity of promutagen 2-aminoanthracene but was not protective against directly acting mutagens sodium azide and 2-nitrofluorene. When tested as a radical scavenger and antioxidant it produced a dose-dependent inhibition. The extract did not show significant antibacterial properties, and was weakly active against dermatophyte and phytopathogenic fungi, but inhibited the growth of phytopathogen Pithyum ultimum. 相似文献
343.
Tavani A Spertini L Bosetti C Parpinel M Gnagnarella P Bravi F Peterson J Dwyer J Lagiou P Negri E La Vecchia C 《Public health nutrition》2006,9(3):369-374
OBJECTIVE: As intake of flavonoids has been associated with reduced risk of coronary heart disease but data on the relation with specific classes of flavonoids are scarce, we assessed the relation between dietary intake of specific classes of flavonoids and the risk of acute myocardial infarction (AMI) in an Italian population.DESIGN: Case-control study. Dietary information was collected by interviewers on a questionnaire tested for validity and reproducibility. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were obtained by multiple logistic regression models including terms for energy and alcohol intake, as well as sociodemographic factors, tobacco and other major recognised risk factors for AMI.SETTING: Milan, Italy, between 1995 and 2003.SUBJECTS: Cases were 760 patients, below age 79 years, with a first episode of non-fatal AMI, and controls were 682 patients admitted to hospital for acute conditions unrelated to diet.RESULTS: A reduced risk of AMI was found for increasing intake of anthocyanidins (OR=0.45, 95% CI 0.26-0.78 for the highest vs. the lowest quintile, Ptrend=0.003) and flavonols (OR=0.65, 95% CI 0.41-1.02, Ptrend=0.02). A tendency towards reduced risks, although not significant, was observed for flavan-3-ols (OR=0.73, 95% CI 0.48-1.10) and total flavonoids (OR=0.74, 95% CI 0.49-1.14). No meaningful heterogeneity was found between the sexes. No association emerged for other flavonoids, including isoflavones, flavanones and flavones.CONCLUSIONS: High intake of anthocyanidins reduced the risk of AMI even after allowance for alcohol, fruit and vegetables, supporting a real inverse association between this class of flavonoids and AMI risk. 相似文献
344.
Effects of dietary soy isoflavones on estrogenic activity,cortisol level,health and growth in rainbow trout,Oncorhynchus mykiss 下载免费PDF全文
Maria Rita Pastore Elena Negrato Carlo Poltronieri Giuseppe Barion Maria Messina Francesca Tulli Cristina Ballarin Lisa Maccatrozzo Giuseppe Radaelli Daniela Bertotto 《Aquaculture Research》2018,49(4):1469-1479
Soy isoflavones (the phytoestrogens genistein, daidzein and glycitein) may act as estrogen receptor agonists or antagonists. The aim of this study was to examine the effect of dietary isoflavones on growth, reproduction and health in rainbow trout (Oncorhynchus mykiss). Rainbow trout fed three experimental diets containing different concentrations of isoflavones (0, 500 and 1,500 ppm). Growth, estrogenic activity, plasma estradiol levels, gonadal development, state of stress and histological changes in selected tissues were evaluated at the end of 70 days. Neither growth performance nor the relative mRNA levels of Insulin Growth Factor I (igf‐I) in the liver were influenced by different levels of dietary isoflavones. Plasma and liver vitellogenin (VTG) protein levels and plasma 17‐β‐estradiol (E2) were unaffected by treatments, although the correlation between plasma levels of E2 and VTG densitometry values was significant (p < .05). The fish gonadosomatic index (GSI) did not significantly differ among the three experimental groups but correlated with plasma VTG densitometry values (p < .05). Plasma, muscle and fin cortisol concentrations fell within the normal welfare range and were not correlated with isoflavone levels. Histologically, the distal intestine showed a normal morphology with well‐differentiated enterocytes and in the liver hepatocytes were also normal. A supranuclear accumulation of lipid droplets in enterocytes and some lipid droplets in hepatocytes were observed in all tested groups, suggesting an impact of basal dietary lipid on transport/metabolism of fat in the fish. Overall, the present results suggest that the doses of isoflavones tested do not compromise rainbow trout reproduction, growth and health. 相似文献
345.
Francesca Cecchi Claudia Russo Daniela Iamartino Alessia Galiero Barbara Turchi Filippo Fratini Sara Degl’Innocenti Raffaele Mazza Stefano Biffani Giovanna Preziuso Carlo Cantile 《Tropical animal health and production》2017,49(6):1135-1142
Paratuberculosis disease is a chronic bacterial disease infection of ruminants of global relevance, caused by MAP (Mycobacterium avium subsp. paratuberculosis). The present study was conducted on the Garfagnina goat breed that is an Italian native goat population registered on the Tuscan regional repertory of genetic resources at risk of extinction. Forty-eight adult goats (27 serologically positive to MAP-positive and 21 serologically negative to MAP-negative) belonging to a single flock that had experienced annual mortalities due to MAP infection were identified and genotyped with the Illumina GoatSNP60 BeadChip. Diagnosis was achieved by serological tests, as well as post-mortem examination of affected animals. A genome-wide scan was then performed on the individual marker genotypes, in an attempt to identify genomic regions associated with MAP infection disease. Nine significant markers were highlighted and they were located within, or nearby, annotated genes. Two genes found in this study encode are linked to protein kinases that are among the most important enzymes involved in the immune response to Johne’s disease, and four genes are involved in the functions of the Golgi complex. 相似文献
346.
Jesús Selfa Carlo Polidori Josep Daniel Asís Luis De Pedro Juli Pujade-Villar José Tormos 《Phytoparasitica》2017,45(1):85-93
The most harmful hymenopteran pests of Pinus sylvestris L. are conifer sawflies from the family Diprionidae, including the widespread Diprion pini (L.). Natural enemies of this pest are still poorly known in many European areas where attacks occur. We studied the egg parasitoids of D. pini at four sites in two mountainous areas of Spain: the Sierra de Francia (western Spain) and the Sierra de Albarracín (eastern Spain). At all sites, the dominant egg parasitoid was Neochrysocharis formosa (Westwood) (Hymenoptera: Eulophidae), whereas other three chalcidoid species were rare. All these species were previously recorded in association with D. pini, but we report here their first record in Spain. Neochrysocharis formosa attacked up to 32.3% of egg clusters of D. pini in the Sierra de Albarracín and 18.5% in the Sierra de Francia. In the attacked egg clusters, this species parasitized up to 35% of eggs in the Sierra de Albarracín and 23.7% in the Sierra de Francia, with a marked female-biased sex ratio. Contrary to the clustered pattern of parasitism observed for N. formosa while attacking other gregarious diprionids, the oviposition in egg clusters of D. pini followed a random pattern, probably due to the froth roof (spumous coating) that covers its eggs and interferes with the egg-searching behavior of females. Indeed, other parasitoid species of D. pini have been reported to behave similarly. 相似文献
347.
Gnocchi Davide Cesari Gianluigi Calabrese Generosa Jenny Capone Roberto Sabbà Carlo Mazzocca Antonio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):33-40
Plant Foods for Human Nutrition - Nowadays, a growing body of evidence supports the view that plants offer an extraordinary opportunity to discover and develop new promising therapeutic strategies... 相似文献
348.
349.
What's in an index? Comparing the ecological information provided by two indices to assess the status of coralligenous reefs in the NW Mediterranean Sea 下载免费PDF全文
350.
Growth and immune response of giant freshwater prawn Macrobrachium rosenbergii (De Man) postlarvae fed diets containing Chlorella vulgaris (Beijerinck) 下载免费PDF全文
Gian Carlo Maliwat Stephanie Velasquez Jan Lorie Robil Merab Chan Rex Ferdinand Traifalgar Melchor Tayamen Janice A Ragaza 《Aquaculture Research》2017,48(4):1666-1676
A 50‐day growth trial was conducted to evaluate the efficacy of Chlorella vulgaris (Beijerinck) as an ingredient in the diets of giant freshwater prawn Macrobrachium rosenbergii (De Man) postlarvae (PL30). Immune response (total haemocyte count and prophenoloxidase activity) was also assessed by subjecting postlarvae to a challenge test against Aeromonas hydrophila (Chester) for 14 days. Iso‐nitrogenous and iso‐lipidic test diets were prepared using a fishmeal‐based‐positive control diet (D0) and four basal diets with inclusion levels of 2% (D2), 4% (D4), 6% (D6) and 8% (D8) C. vulgaris. Postlarvae of M. rosenbergii were randomly stocked (mean initial body weight of 0.19 ± 0.02 g) in 30‐L tanks in three replicates per dietary treatment for evaluation of growth performance. Another set of postlarvae (mean initial body weight of 1.25 ± 0.02 g) was randomly distributed in 95‐L tanks in three replicates per dietary treatment for the assessment of immune response. Results showed that specific growth rate was significantly higher (P < 0.05) in postlarvae fed D4 and D6. Variations in values for carcass protein, lipid, moisture and ash were also evident. Postlarvae fed diets with Chlorella showed increased prophenol oxidase activity and total haemocyte counts. Moreover, survival rate after challenge with A. hydrophila was significantly increased (P < 0.05). Inclusion of C. vulgaris in diets enhanced immune response and resistance of M. rosenbergii postlarvae against A. hydrophila infection. 相似文献