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排序方式: 共有263条查询结果,搜索用时 15 毫秒
81.
A. M. Gargiulo P. Ceccarelli C. Dall'aglio V. Pedini 《Anatomia, histologia, embryologia》1997,26(4):331-336
An ultrastructural study has been made of gastric mucosa of a teleostean fish, Tilapia spp. The cytological features of the surface mucous cells, mucous neck cells, glandular cells and endocrine cells are described. The surface mucous cells, identified by their superficial localization, are characterized by apical granules. The mucous neck cells are distinguished by the appearance of their mucous granules and their localization between surface mucous cells and glandular cells. The gastric glands contain only one form of cell whose fine structure is similar to cells that secrete hydrochloric acid. Physiological implications of some ultrastructural features are also discussed. 相似文献
82.
The Bovine tongue possesses numerous circumvallate papillae (8–16) each side). The troughs around the papillae are the openings of the ducts of the gustatory (von Ebner's) glands. In this study, we have characterized in situ the glycosidic composition of the secretion of bovine gustatory glands using traditional histochemical methods and lectin histochemistry with and without prior neuraminidase (sialidase) digestion. The lectin-horseradish peroxidase conjugates employed were: PNA, DBA, SBA, WGA, LTA, UEA I and ConA. Acinar cells show a diffuse positivity towards PAS and Alcian blue at pH 2.5 and the most intense and homogeneous lectin staining was obtained with PNA. This indicates that bovine gustatory glands secrete glycoproteins with 1,2-glycol containing hexoses and carboxyl-rich glycoconjugates and that galactosyl (β1 → 3) Nacetylgalactosamine is the most frequent sugar residue present in these glycoproteins. Results were compared with data reported in the literature on the same glands of other species. 相似文献
83.
Bessa MC Michael GB Canu N Canal CW Cardoso M Rabsch W Rubino S 《Research in veterinary science》2007,83(3):302-310
This study aimed to investigate the relatedness of porcine Salmonella enterica subsp. enterica (S.) serovar Typhimurium strains isolated in Southern Brazil. Sixty-six isolates from pigs belonging to three commercial companies were submitted to phage typing, XbaI-macrorestriction (PFGE), IS200 hybridization, rep-PCR, antimicrobial susceptibility testing, and PCR assay targeting the spvR region. All strains presented a unique rep-PCR pattern and 63 strains had a common IS200 profile. One pulse-type (XA) was the most prevalent (39/66 strains) and included strains of phage types DT177, DT192, DT194 and RDNC. The spvR region was detected in three strains, which harboured plasmids of 90 kb. High rates of tetracycline, sulfonamide and streptomycin resistance were found. Isolates from farms located in different geographic regions but associated to the same commercial companies clustered together and presented a common resistance profile. Results suggested that clonal groups of S. Typhimurium are present in pig commercial companies in Southern Brazil. 相似文献
84.
Fiorito Serena Epifano Francesco Palumbo Lucia Genovese Salvatore 《Plant foods for human nutrition (Dordrecht, Netherlands)》2021,76(3):397-398
Plant Foods for Human Nutrition - The aim of this study was to establish a convenient process to get auraptene-enriched blends from Citrus limon L. Osbeck (Rutaceae) peels powder with functional... 相似文献
85.
Cao Yu Reitz Stuart R. Germinara Giacinto Salvatore Wang Chun Wang Lijuan Yang Siyu Gao Yulin Zhang Wenqing Li Can 《Journal of pest science》2022,95(2):761-770
Journal of Pest Science - Thrips hawaiiensis is a common thrips pest that damages the flowers of various plants. The differing population sizes of T. hawaiiensis among host plants suggest its... 相似文献
86.
87.
Seu R Phillips RJ Alberti G Biccari D Bonaventura F Bortone M Calabrese D Campbell BA Cartacci M Carter LM Catallo C Croce A Croci R Cutigni M Di Placido A Dinardo S Federico C Flamini E Fois F Frigeri A Fuga O Giacomoni E Gim Y Guelfi M Holt JW Kofman W Leuschen CJ Marinangeli L Marras P Masdea A Mattei S Mecozzi R Milkovich SM Morlupi A Mouginot J Orosei R Papa C Paternò T Persi del Marmo P Pettinelli E Pica G Picardi G Plaut JJ Provenziani M Putzig NE Russo F Safaeinili A Salzillo G 《Science (New York, N.Y.)》2007,317(5845):1715-1718
Mars' polar regions are covered with ice-rich layered deposits that potentially contain a record of climate variations. The sounding radar SHARAD on the Mars Reconnaissance Orbiter mapped detailed subsurface stratigraphy in the Promethei Lingula region of the south polar plateau, Planum Australe. Radar reflections interpreted as layers are correlated across adjacent orbits and are continuous for up to 150 kilometers along spacecraft orbital tracks. The reflectors are often separated into discrete reflector sequences, and strong echoes are seen as deep as 1 kilometer. In some cases, the sequences are dipping with respect to each other, suggesting an interdepositional period of erosion. In Australe Sulci, layers are exhumed, indicating recent erosion. 相似文献
88.
Riccardo Aversano Maria Raffaella Ercolano Luigi Frusciante Luigi Monti James M. Bradeen Gennaro Cristinzio Astolfo Zoina Nicola Greco Salvatore Vitale Domenico Carputo 《Genetic Resources and Crop Evolution》2007,54(8):1797-1806
Worldwide, a variety of pathogens negatively affect potato production, resulting in an estimated 22% annual yield reduction.
Wild Solanum species represent a unique gene pool where all the traits necessary to improve the cultivated potato can be found.
Therefore, breeding efforts for improved disease resistance and research aimed at characterizing wild germplasm have been
extensively made. In this paper, sources of resistance to Phytophthora
infestans, Erwinia carotovora subsp. carotovora, Fusarium solani and Globodera spp. have been investigated in several clones of two Solanum species originating from Central Mexico (S. bulbocastanum and S. cardiophyllum). Interestingly, we found sources of combined resistance to late blight and bacterial soft rot. This is an important finding
considering that the development of resistant potato varieties has been hindered by the scarcity of resistant germplasm. In
addition, we explored molecular differences within and between the two species generating AFLP fingerprints. By means of six
primer pair combinations, we found 13 and 16 putative species-specific AFLP markers for S. bulbocastanum and S. cardiophyllum, respectively, and a bounty of markers useful for mapping, MAS, and cloning purposes. The phenotypic and molecular information
associated to S. bulbocastanum and S. cardiophyllum for designing strategies of assisted selection are discussed. 相似文献
89.
Amato ME Ansanelli G Fisichella S Lamanna R Scarlata G Sobolev AP Segre A 《Journal of agricultural and food chemistry》2004,52(4):823-831
Starch enzymatic degradation caused by endogenous hydrolases is studied by in situ NMR spectroscopy on a set of hard and soft wheat flours. The results obtained by two different techniques (HR-MAS and (1)H NMR in solution) are analyzed in terms of a Michaelis-Menten kinetic phenomenological model taking into account the presence of endogenous enzymes and their eventual inactivation. The parameters resulting from the best fit of all experimental data to the kinetic model equations are submitted to a multivariate statistical analysis to assess the role of the oligosaccharides release in distinguishing between hard and soft wheats. 相似文献
90.
Simonetti P Ciappellano S Gardana C Bramati L Pietta P 《Journal of agricultural and food chemistry》2002,50(21):6217-6221
The purpose of this study was to evaluate the effect of supplementation with procyanidins from Vitis vinifera on markers of oxidative stress. Ten healthy volunteers received a daily dose of 110 mg of procyanidins for 30 days. Fasting venous blood samples were taken before and at the end of the supplementation period and after 7 days of wash-out. The total antioxidant activity and the plasma concentrations of alpha-tocopherol were not modified. Conversely, the levels of alpha-tocopherol in red blood cell membranes increased significantly from 1.8 +/- 0.1 to 2.8 +/- 0.2 mg/g. Similarly, the lymphocyte oxidized DNA [8-oxo-7,8-dihydro-2'-deoxyguanosine/2'-deoxyguanosine ratio] was reduced from 7.23 +/- 2.47 to 2.34 +/- 0.51, and the red blood cell membrane fatty acid composition shifted to a higher level of polyunsaturated fatty acids. On the basis of these results, it may be suggested that dietary procyanidins exert their antioxidant protection in vivo by sparing liposoluble vitamin E and reducing DNA oxidative damage. 相似文献