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排序方式: 共有217条查询结果,搜索用时 31 毫秒
21.
Wilson DS Teagle DA Alt JC Banerjee NR Umino S Miyashita S Acton GD Anma R Barr SR Belghoul A Carlut J Christie DM Coggon RM Cooper KM Cordier C Crispini L Durand SR Einaudi F Galli L Gao Y Geldmacher J Gilbert LA Hayman NW Herrero-Bervera E Hirano N Holter S Ingle S Jiang S Kalberkamp U Kerneklian M Koepke J Laverne C Vasquez HL Maclennan J Morgan S Neo N Nichols HJ Park SH Reichow MK Sakuyama T Sano T Sandwell R Scheibner B Smith-Duque CE Swift SA Tartarotti P Tikku AA Tominaga M Veloso EA 《Science (New York, N.Y.)》2006,312(5776):1016-1020
Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D. 相似文献
22.
Fernández-Varón E Villamayor L Escudero E Espuny A Cárceles CM 《Veterinary journal (London, England : 1997)》2006,172(2):302-307
The pharmacokinetics of moxifloxacin was studied following intravenous (IV) and subcutaneous (SC) administration of 5 mg/kg to healthy lactating goats (n = 6). Moxifloxacin concentrations were determined by high performance liquid chromatography assay with fluorescence detection. The moxifloxacin plasma concentration versus time data after IV administration could best be described by a two compartment open model. The disposition of SC administered moxifloxacin was best described by a one-compartment model. The plasma moxifloxacin clearance (Cl) for the IV route was 0.43 +/- 0.02 L/kg (mean +/- SE). The steady-state volume of distribution (Vss) was 0.79 +/- 0.08 L/kg. The terminal half-life (t1/2lambdaz) was 1.94 +/- 0.41 and 2.98 +/- 0.48 h after IV and SC administration, respectively. The absolute bioavailability was 96.87 +/- 10.27% after SC administration. Moxifloxacin penetration from blood to milk was quick for both routes of administration and the high AUCmilk/AUCplasma and Cmax-milk/Cmax-plasma ratios reached indicated a wide penetration of moxifloxacin into the milk. From these data, it appears that a 5 mg/kg SC dose of moxifloxacin would be effective in lactating goats against bacterial isolates with MIC < or = 0.20 microg/mL in plasma and MIC < or = 0.40 microg/mL in milk. 相似文献
23.
Lee SH Lillehoj HS Jang SI Lee KW Baldwin C Tompkins D Wagner B Del Cacho E Lillehoj EP Hong YH 《Veterinary immunology and immunopathology》2012,145(1-2):527-533
This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD83 (chCD83), a membrane-bound glycoprotein belonging to the immunoglobulin superfamily that is primarily expressed on mature dendritic cells (DCs). A recombinant chCD83/IgG4 fusion protein containing the extracellular region of chCD83 was expressed in Chinese Hamster Ovary (CHO) cells and isolated from the spent cell culture medium by protein G affinity chromatography. The extracellular region of the chCD83 protein was purified and used to immunize mice. A cell fusion was performed, from which 342 hybridomas were screened for mAbs to chCD83. Two mAbs, chCD83-159 and chCD83-227, stained the greatest percentage of chCD83-transfected CHO cells and were selected for further characterization. By flow cytometry, both mAbs reacted with a chicken macrophage cell line, HD11. Both mAbs also recognized a single 53 kDa protein on Western blots of lysates from lipopolysaccharide-stimulated spleen mononuclear cells or unstimulated HD11 cells. Immunostaining of chicken secondary lymphoid organs identified chCD83(+) cells with morphologic and subtissue localization properties comparable to mammalian DCs. In vitro stimulation of spleen mononuclear cells with concanavalin A (Con A) decreased the percentage of chCD83(+) cells compared with cells treated with medium alone. Interestingly, spleen cells treated with Con A in the presence of chCD83-227 mAb exhibited decreased percentage of MHCII(+) cells compared with cells treated with an isotype-matched negative control mAb. These chCD83 mAbs may be useful for future investigations of chicken immune cell maturation and mechanisms of action. 相似文献
24.
Berta Caballero-López José M. Blanco-Moreno Nicolás Pérez-Hidalgo José M. Michelena-Saval Juli Pujade-Villar Emilio Guerrieri José A. Sánchez-Espigares F. Xavier Sans 《Journal of pest science》2012,85(1):81-88
The aphid–natural enemy interaction in winter wheat fields constitutes a complex system that has been frequently studied because
of its implication for biological control. However, not all of the aphids living in cereal fields are crop pests, as there
are also aphids living on weeds that may serve as alternative hosts or prey for aphid parasitoids or predators. In this context,
a concomitant survey of the plant and insect communities was conducted to understand how different plant communities affect
the abundance and richness of aphids and the interactions with their natural enemies. The plant community was split into functional
groups (grasses, legumes and forbs), and the aphid community was divided into feeding groups according to their host preferences
(specialists in grasses or forbs). The grass aphids, which dominated the total aphid catches, responded positively to grass
cover, which was particularly enhanced in the conventional fields. Conversely, the forb aphids, which mainly conditioned the
total species richness of the aphids, were closely correlated with the local abundance of legumes. The system of cereal aphid-parasitoids
was enhanced in the conventional fields, where the abundance of grasses was higher, whereas the legumes of the organic fields
indirectly played a key role in enhancing the richness of the parasitoids and the abundance of predators. Our findings indicate
that a bottom-up effect exists throughout the plant community, aphids, and aphidophagous insects and that plant community
characteristics should be considered to better understand cereal aphid control. 相似文献
25.
Domenico Vecchio Rossella Di Palo Esterina De Carlo Luigi Esposito Giorgio Antonio Presicce Alessandra Martucciello Emilio Chiosi Pasquale Rossi Gianluca Neglia Giuseppe Campanile 《Tropical animal health and production》2013,45(8):1697-1702
Growth, weight at birth and daily weight gain (DWG) on 12 water buffalo calves, starting from 6 days of age until completion of weaning, was investigated in this study. Different feeding regimens were given to two groups of animals with regard to daily milk replacer: (1) group 1 (G1) received a double concentration in single administration; whereas (2) group 2 (G2) received the same amount of milk replacer split twice daily. Blood samples were collected from each calf on days 6, 30, 60 and 90 to evaluate acute phase proteins (haptoglobin), bactericide activity, lysozime, total protein content and biochemical parameters. No differences were observed between the two groups in terms of dry matter intake, feed efficiency and live body weight at the end of the study. Interestingly, a significantly (P?<?0.05) reduced DWG was observed earlier in G1 (day 45) than in G2 (day 60). Gastrointestinal disorders were not recorded throughout the experimental period, and no significant differences were recorded between the two groups for all considered parameters. This study confirms the possibility of utilising one daily administration of milk replacer in water buffalo calf during weaning. This new approach facilitates calves management, without interfering with calves growing performances. 相似文献
26.
27.
Lia Koski Emilio DeBess Hilary E. Rosen Roshan Reporter Thomas Waltz Molly Leeper Jeniffer Concepcion Acevedo Renta Karpíkov Jacquelyn McCormick Tereza Gelbicova Brenda Morningstar-Shaw Megin Nichols Richard F. Leman 《Zoonoses and public health》2019,66(8):974-977
Reptile contact can result in zoonotic non‐typhoidal salmonellosis. In April 2018, Oregon Public Health Division contacted CDC about a cluster of four Salmonella serovar Fluntern (SF) illnesses in four states (OR, CA, IA, NY); patients reported contact with geckos, a popular reptile pet. PulseNet, the national molecular subtyping network of food‐borne disease surveillance, subsequently identified additional SF clinical isolates. Twelve cases in 11 states were identified; median age was 5 years (range: <1–58 years). Three patients were hospitalized; no deaths were reported. Of those with exposure information (n = 10), all reported reptile exposure; 9 (90%) specified contact with leopard geckos. No common source of geckos was identified from reported purchase locations. Los Angeles County (LAC) health officials isolated SF from one patient's leopard gecko. Five reptile/gecko isolates were identified from the USDA National Veterinary Services Laboratories (NVSL) from 2015 to 2018. Five countries responded to an Epidemic Intelligence Information System post by PulseNet; reptile isolate sequence data were received from Czech Republic. A clinical case from England was identified through the National Center for Biotechnology Information pathogen detection pipeline; the patient did not report contact with leopard geckos. Whole genome sequencing analysis revealed substantial genetic diversity between clinical and animal isolates; however, gecko and clinical isolates from LAC were highly related (1 allele difference). This investigation linking SF illnesses to leopard geckos highlights an important public health risk from pets. A better understanding of how geckos are distributed by the pet industry in the United States could improve traceability to points of origin and mitigate Salmonella transmission at gecko breeders. Earlier NVSL reports of SF isolates from geckos suggest the risk of human SF infection from geckos is not new. This investigation demonstrates a need to educate gecko breeders, retailers and gecko owners about the continued Salmonella infection risk from pet geckos. 相似文献
28.
Sosa ER Landsberg JH Kiryu Y Stephenson CM Cody TT Dukeman AK Wolfe HP Vandersea MW Litaker RW 《Journal of aquatic animal health》2007,19(1):41-48
Based on isolations from naturally infected fish in Florida, we investigated the role of the fungi Aphanomyces invadans, Achlya bisexualis, and Phialemonium dimorphosporum in the etiology of ulcerative mycosis (UM) in striped mullet Mugil cephalus. We injected healthy striped mullet subcutaneously with secondary zoospores of four oomycete isolates: two concentrations (50 and 115 zoospores/mL) of SJR (an endemic isolate of Aphanomyces invadans in American shad Alosa sapidissima from the St. Johns River); two concentrations each of CAL (25 and 65 zoospores/mL) and ACH (1,400 and 2,000 zoospores/mL; endemic isolates of Aphanomyces invadans and Achlyva bisexualis, respectively, in striped mullet from the Caloosahatchee River); and two concentrations of the ascomycete culture MTZ (2,500 and 3,500 zoospores/mL; endemic isolate of P. dimorphosporum from whirligig mullet M. gyrans in the Matanzas Inlet). All fish injected with either concentration of SJR developed granulomatous ulcers after 8 d and died within 21 d. Eighty percent (8/10) of fish injected with the high dose of CAL developed ulcers after 13 d and died within 28 d, but only 30% (3/10) of fish injected with the low dose of CAL developed ulcers. Four of the ulcerated fish died within 28 d, and the remaining fish were terminated after 32 d. Fish injected with zoospores of Aphanomyces invadans developed ulcers that were grossly and histologically similar to those observed in naturally infected striped mullet with UM from several estuaries or rivers in Florida. These hemorrhagic skin ulcers were characterized by myonecrosis and the presence of mycotic granulomas. None of the fish injected with ACH, MTZ, or sterile water developed ulcers. This study fulfilled Koch's postulates and demonstrated that ulcers could be experimentally induced in striped mullet after exposure via injection to secondary zoospores of an endemic Florida strain of Aphanomyces invadans. 相似文献
29.
Cárceles CM Fernández-Varón E Marín P Escudero E 《Veterinary journal (London, England : 1997)》2007,174(1):154-159
Tissue disposition of azithromycin after intravenous (IV) or intramuscular (IM) injection at a single dose rate of 10mg/kg bodyweight were investigated in rabbits using a modified agar diffusion bioassay for determining tissue concentrations. The pharmacokinetic behaviour of azithromycin was characterized by low and sustained plasma concentrations but high and persistent tissue concentrations. Kinetic parameters indicated a high retention of the drug in peripheral compartments. The plasma half-lives after IV and IM administrations were similar being 21.8h and 23.1h, respectively, while the half-lives obtained in tissues after IV and IM administration were at least 1.4 and 1.9 times longer than in plasma, respectively. The highest tissue concentrations were found in bile, liver and spleen whereas the lowest ones were found in skeletal muscle (although they were higher than those in plasma). From the results of the single administration in this study an IM dosage regimen can be proposed that achieves minimum concentrations over 2mg/L in rabbits: three doses of 4-5mg/kg/day would provide suitable therapeutic concentrations in pulmonary tissues over seven days. 相似文献
30.
Granulocyte colony-stimulating factors (G-CSFs) and granulocyte macrophage colony-stimulating factors (GM-CSFs) are endogenous cytokines that regulate granulocyte colonies and play a major role in the stimulation of granulopoiesis (neutrophils, basophils and eosinophils) and in the regulation of microbicidal functions. There are numerous pathological conditions in which neutrophils are decreased, the most common being neutropenia associated with cancer chemotherapy, which increases the risk of serious microbial infections developing with the potential for high morbidity and mortality. New methods in molecular biology have led to the identification and cloning of CSF genes and biopharmaceutical production. Since then, CSFs have been widely used for the prevention and treatment of neutropenia associated with cancer chemotherapy, for mobilising haematopoietic cell precursors, and for other neutropenia-related pathologies. This review focuses on the use of CSFs within both human and veterinary medicine. Clinical applications, pharmacology, tolerability and the potential role of these factors in veterinary medicine are considered. 相似文献