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排序方式: 共有211条查询结果,搜索用时 12 毫秒
61.
62.
Lustbader JW Cirilli M Lin C Xu HW Takuma K Wang N Caspersen C Chen X Pollak S Chaney M Trinchese F Liu S Gunn-Moore F Lue LF Walker DG Kuppusamy P Zewier ZL Arancio O Stern D Yan SS Wu H 《Science (New York, N.Y.)》2004,304(5669):448-452
Mitochondrial dysfunction is a hallmark of beta-amyloid (Abeta)-induced neuronal toxicity in Alzheimer's disease (AD). Here, we demonstrate that Abeta-binding alcohol dehydrogenase (ABAD) is a direct molecular link from Abeta to mitochondrial toxicity. Abeta interacts with ABAD in the mitochondria of AD patients and transgenic mice. The crystal structure of Abeta-bound ABAD shows substantial deformation of the active site that prevents nicotinamide adenine dinucleotide (NAD) binding. An ABAD peptide specifically inhibits ABAD-Abeta interaction and suppresses Abeta-induced apoptosis and free-radical generation in neurons. Transgenic mice overexpressing ABAD in an Abeta-rich environment manifest exaggerated neuronal oxidative stress and impaired memory. These data suggest that the ABAD-Abeta interaction may be a therapeutic target in AD. 相似文献
63.
Maria Caria Carlo Boselli Angela Calvo Silverio Grande Giuseppe Todde 《Animal Science Journal》2021,92(1):e13667
The objectives of this study were to evaluate and compare the effect of working vacuum levels (35 and 44 kPa) and liners dimensions (mouthpiece lip diameter and overall length, 20–185 and 22–170 mm) on the main milking characteristics of goats. The results highlight that both the working vacuum level and the liner dimension have influenced the milk flow curve parameters. The maximum variations were found for peak flow rate, which increased significantly with liner dimensions of 20–185 mm at a working vacuum level of 44 kPa as well as average milk flow rate and for plateau phase duration. The incorrect adoption of operative parameters and unsuitable milking machine components, might affect the performance of the mechanical milking and negatively affecting animal productions and welfare. 相似文献
64.
Casiraghi M Bazzocchi C Mortarino M Ottina E Genchi C 《Veterinary parasitology》2006,141(3-4):368-372
Accurate diagnosis of canine filariosis is essential for choosing correct therapeutic approach. Therefore, reliable methods for discriminating among the different filarial infections in dogs are needed. The authors report simple and highly specific molecular methods that identify the three most common filarial nematodes of European dogs: Dirofilaria immitis, D. repens and Acanthocheilonema (syn. Dipetalonema) reconditum, based on (1) PCR amplifications of mitochondrial DNA (12S rDNA and coxI) with general filarial primers followed by digestion with restriction enzymes that generates band polymorphisms clearly discriminating the three species and (2) PCR amplifications with species-specific primers to support the restriction analysis, in particular in the case of multiple infections. 相似文献
65.
Paolo Bruno Maurizio Caselli Gianluigi de Gennaro Lucia Scolletta Livia Trizio Maria Tutino 《Water, air, and soil pollution》2008,193(1-4):37-50
Volatile organic compounds (VOC) have been monitored in 12 sites of Canosa di Puglia, a city located in the Southern of Italy, in order to identify the main VOC source—vehicular traffic or industrial—and to evaluate the critical situations in the city. Monitoring, carried out by using Radiello® diffusive samplers, has been planned taking into account the traffic density and the architecture of the city. From the study of the data it has been emerged that, among all considered VOC, benzene, toluene, ethylbenzene and xylenes (BTEX) are the pollutants at higher concentration. However no critical situation has appared from the present monitoring. Maps of daily benzene and toluene concentrations have shown that the most significant pollution phenomena happens in the center of the urban area which is in a valley with narrow roads and high buildings that do not allow an efficient dispersion of pollutants. The study of the diagnostic ratios between the toluene and benzene concentrations in the several areas (average T/B?=?3.4) and the high Pearson’s coefficient among the pollutants, and in particular between benzene and toluene concentrations (r?=?0.9505), have suggested that in urban area these pollutants are emitted from the same source: the vehicular traffic. 相似文献
66.
Angioni A Barra A Arlorio M Coisson JD Russo MT Pirisi FM Satta M Cabras P 《Journal of agricultural and food chemistry》2003,51(4):1030-1034
The chemical composition of the essential oil of the Sardinian dwarf curry plant [Helichrysum italicum G. Don ssp. microphyllum (Willd) Nym] was studied. Genetic analysis suggested the presence of two chemotypes; morphological and chemical differences confirmed the presence of two chemotypes (A and B). The maximum yields were 0.18 and 0.04% (v/w) for flowering tops and stems, respectively. The concentrations of nerol and its esters (acetate and propionate), limonene, and linalool reach their highest values during the flowering stage both in flowers and in stems. Besides the essential oil, type B showed an interesting antifungal activity. 相似文献
67.
Albania is facing serious problems with the national food safety control system in terms of legislation, control and enforce-ment. The objective of this paper is to analyse consumer perceptions about s... 相似文献
68.
Ambra Panti Stephen N. Greenhalgh Maurizio Longo Tiziana Liuti 《Veterinary anaesthesia and analgesia》2018,45(6):802-810
Objective
To examine the effect of sternal or lateral recumbency, with or without cranial extension of the hindlimbs, on the distance between the dorsal lumbosacral laminae in dogs.Study design
Blinded, randomized, crossover, experimental study.Animals
A total of 19 canine cadavers.Methods
Computed tomography of the lumbosacral junction was performed in four positions: sternal and right lateral recumbency, with hindlimbs extended cranially or not. Order of positioning was randomized. The lumbosacral interlaminar (LSI) distance, defined as the distance between the dorsal laminae of the seventh lumbar vertebra (caudal margin) and sacrum (cranial margin), was measured for each position by two independent assessors who were unaware of positioning. Mean distances in each position were compared using a paired t-test, corrected for multiple comparisons.Results
For n = 19 cadavers [6 female; median (range) age 9 (0.3–16) years; weight, 20.4 (1.0–34.0) kg], cranial extension of the hindlimbs increased the LSI distance, compared with control, in both sternal (9.2 ± 2.2 mm versus 3.1 ± 1.3 mm, p < 0.001) and right lateral recumbency (8.2 ± 1.9 mm versus 4.9 ± 1.5 mm, p < 0.001). With the hindlimbs extended cranially, sternal recumbency increased LSI distance when compared with right lateral recumbency (p < 0.001).Conclusions and clinical relevance
Cranial extension of the hindlimbs in both sternal and lateral recumbency increases the LSI distance to an extent that is both statistically significant and of potential clinical relevance. Although ease of epidural access or injection was not assessed, the small (1 mm) difference in LSI distance between cranial hindlimb extension in sternal and right lateral recumbency is unlikely to be of clinical relevance. Conversely, cranial extension of the hindlimbs in either sternal or lateral recumbency would be expected to facilitate epidural injection. 相似文献69.
Perugini M Visciano P Manera M Turno G Lucisano A Amorena M 《Journal of agricultural and food chemistry》2007,55(5):2049-2054
Polycyclic aromatic hydrocarbons (PAHs) were determined by an HPLC method with fluorescence detection in bivalves (Mitylus galloprovincialis), cephalopods (Todarodes sagittatus), crustaceans (Aristeus antennatus), and fish (Mullus surmeletus, Scomber scombrus, Micromesistius poutassou, and Merluccius merluccius) caught in the Gulf of Naples (Tyrrhenian Sea, Italy). Anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, and benzo(k)fluoranthene were detected, at different concentrations, in all of the examined marine organisms, whereas benzo(a)pyrene, dibenz(a,h)anthracene, benzo(g,h,i)perylene, and indeno(1,2,3-cd)pyrene were found only in Mediterranean mussels. Of mussels collected in winter 71.43% exceeded the maximum residual levels (MRL) fixed for the benzo(a)pyrene in European Regulation 208/2005/EC, whereas all samples collected in summer reported values lower than this limit. In comparison to the other marine organisms, the mussels showed the highest PAH concentrations (p < 0.01). Fish showed total PAH levels lower than those of cephalopods and, in particular, European hake showed the lowest values (6.06 ng/g of fresh weight). 相似文献
70.
Loizzo Monica R. Tundis Rosa Sut Stefania Dall’Acqua Stefano Ilardi Vincenzo Leporini Mariarosaria Falco Tiziana Sicari Vincenzo Bruno Maurizio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):124-130
Plant Foods for Human Nutrition - This study aimed at evaluating and comparing the chemical profile obtained by HPLC-ESI-MSn analysis, the inhibitory activity of enzymes linked to obesity... 相似文献