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991.
Between October 1999 and January 2000 all together 151 male pheasants were examined for endoparasites. 33 one-year-old birds came from two pheasantries, the remaining 118 birds, aged between one and five years, were wildlife animals. The infestation extensy of all pheasants with endoparasites were 96.7%. A mostly low infestation with coccidia of the three species Eimeria (E.) phasiani, E. duodenalis and E. tetartooimia were detected in 41% of all birds. E. tetartooimia was found in Germany for the first time. In 67.5% of the pheasants the five different species of capillaria (Capillaria (C.) annulata, C. bursata, C. contorta, C. perforans, C. phasianina) and in 84.1% the nematode Heterakis gallinarum were present. Pheasants in the capture group showed higher infestation intensy and extensy. In 51.5% of the pheasants of the capture group Syngamus trachea was present. In one pheasant an acanthocephalus (Plagiorhynchus cylindraceus) was detected for the first time in Germany and in two pheasants a trematode of the genus Echinostoma was present. 相似文献
992.
Pasquali P Fayer R Zarlenga D Canals A Marez Td Gomez Munoz MT Almeria S Gasbarre LC 《Veterinary parasitology》2006,135(3-4):259-268
This study was undertaken to determine if administration of recombinant bovine interleukin-12 (rBoIL-12) could stimulate a cellular immune response that protected calves from an oral challenge inoculation with Cryptosporidium parvum oocysts. In a first experiment, rBoIL-12 intraperitoneally administered as a single dose 1 day before challenge inoculation, did not alter the course of infection. The percentage of immune competent cells and levels of cytokine gene expression in the ileo-cecal mucosa and in the draining lymph nodes of treated calves were similar to those of untreated control calves. However, when rBoIL-12 was subcutaneously administered daily from 2 days before infection to 2 days after infection, a consistent increase of T lymphocytes and an higher expression of interferon-gamma (IFN-gamma) was detected. Again, treatment did not alter the course of infection. Similar results were obtained when rBoIL-12 was administered daily for 4 days beginning 2 days after oral inoculation. These data indicate that although rBoIL-12 stimulated a strong immune response in the gut of neonatal calves, the response was not able to provide protection from challenge inoculation with C. parvum oocysts. 相似文献
993.
McLellan GJ Aquino SM Mason DR Kinyon JM Myers RK 《Journal of the American Animal Hospital Association》2006,42(4):302-307
Orbital infection with Aspergillus fumigatus was diagnosed in a Persian cat that was presented with chronic third eyelid protrusion and exophthalmos. Evidence of nasal, sinus, or disseminated aspergillosis was not detected in this cat. Complete surgical excision of diseased tissues was not possible during orbital exenteration, and infection subsequently extended into the tissues of the oral cavity. Oral therapy with itraconazole and parenteral therapy with amphotericin B were ineffective in resolving the infection. Oral therapy with a novel triazole, posaconazole, was curative. 相似文献
994.
Caston SS McClure SR Martens RJ Chaffin MK Miles KG Griffith RW Cohen ND 《Veterinary therapeutics : research in applied veterinary medicine》2006,7(4):361-375
This study evaluated the prophylactic effectiveness of hyperimmune plasma (HIP) as an aid in the prevention of pneumonia caused by experimental infection with Rhodococcus equi. Thirty neonatal foals were administered R. equi HIP or saline at 2 days of age and were infected with virulent R. equi at 7 days. All foals developed signs or symptoms of respiratory disease. Radiographic scores on day 28 and neutrophil concentrations on day 49 were significantly greater in control foals, and time to respiratory effort score of 2 or higher was significantly shorter for control foals. Three foals, all in the principal group, died or were euthanized before the end of the study, but there was no significant difference in mortality between groups. VapA titers were significantly greater in principal foals. Administration of R. equi HIP decreased the severity of radiographic lesions and prolonged time to increased respiratory effort due to R. equi-induced pneumonia. 相似文献
995.
Habashi JP Judge DP Holm TM Cohn RD Loeys BL Cooper TK Myers L Klein EC Liu G Calvi C Podowski M Neptune ER Halushka MK Bedja D Gabrielson K Rifkin DB Carta L Ramirez F Huso DL Dietz HC 《Science (New York, N.Y.)》2006,312(5770):117-121
Aortic aneurysm and dissection are manifestations of Marfan syndrome (MFS), a disorder caused by mutations in the gene that encodes fibrillin-1. Selected manifestations of MFS reflect excessive signaling by the transforming growth factor-beta (TGF-beta) family of cytokines. We show that aortic aneurysm in a mouse model of MFS is associated with increased TGF-beta signaling and can be prevented by TGF-beta antagonists such as TGF-beta-neutralizing antibody or the angiotensin II type 1 receptor (AT1) blocker, losartan. AT1 antagonism also partially reversed noncardiovascular manifestations of MFS, including impaired alveolar septation. These data suggest that losartan, a drug already in clinical use for hypertension, merits investigation as a therapeutic strategy for patients with MFS and has the potential to prevent the major life-threatening manifestation of this disorder. 相似文献
996.
Neutrophil extracellular trap formation by bovine neutrophils is not inhibited by milk 总被引:1,自引:0,他引:1
Lippolis JD Reinhardt TA Goff JP Horst RL 《Veterinary immunology and immunopathology》2006,113(1-2):248-255
Neutrophils are the first line of defense in a mammary gland infection. However, the process of neutrophil transmigration across a membrane and ingestion of fat and/or casein when incubated in milk have been shown to inhibit bacterial phagocytosis and oxidative burst functions. Recently, a killing mechanism has been described whereby stimulated neutrophils release nuclear and granule material in fibrous webs that physically trap and kill bacteria. We demonstrate that these neutrophil extracellular traps are also produced by bovine blood neutrophils stimulated with PMA/ionomycin. Importantly, neutrophil extracellular traps can be formed when neutrophils have been incubated for up to 6h in milk prior to stimulation. This contrasts milk's rapid inhibition of bacterial phagocytosis and oxidative burst functions in the neutrophil. Furthermore, stimulation of neutrophils with bacteria common to mammary gland infections leads to neutrophil extracellular traps being formed in milk. Some bacteria tested stimulated enhanced formation of neutrophil extracellular traps in milk compared to culture media. Therefore, being unaffected by incubation in milk may indicate an important role for neutrophil extracellular traps in defense against mastitis. 相似文献
997.
The United Nations Framework Convention on Climate Change andits Kyoto Protocol (KP) have created a clear need for methodsthat enable accurate accounting of carbon (C) stocks and stockchanges in forest ecosystems. The rate of accumulation of Cin plantation forests in the Republic of Ireland was estimatedfor the period 19062002 using the record of afforestationand a dynamic C accounting model (C-flow). Projections for theperiod 20032012 were made using different afforestationrates. It was assumed that Sitka spruce planted in the period19061989 was Yield Class (YC) 16 m3 ha1 year1and that after 1990 this increased to 20 m3 ha1 year1.All other conifers were assumed to have the growth characteristicsof YC 8 m3 ha1 year1 lodgepole pine. Broadleaveswere assumed to have the growth characteristics of YC 6 m3 ha1year1 beech. In 2002, the total forest C stock was 37.7Mt C representing an increase of 14.8 Mt C since 1990. In 2002,the rate of increase in trees, products, litter and soil was0.7, 0.1, 0.1 and 0.5 Mt C, respectively. Under a business-as-usualscenario, afforestation since 1990 is estimated to create anannual average C sink of 0.9 Mt C year1 during the period20082012. This accounts for 22 per cent of Ireland'sreduction commitment under the KP. Afforestation on peat soilswas found to reduce the net C sink, although the extent to whichit does so is highly dependent on assumptions regarding therate of peat C loss. 相似文献
998.
Mevalonate kinase (MK) catalyzes a step in the isoprenoid biosynthetic pathway, which leads to a huge number of compounds that play important roles in plant growth and development. Here, we report on changes in MK activity in white pine (Pinus strobus L.) during plant regeneration by adventitious shoot organogenesis from cotyledons of mature embryos, including nodular callus induction, shoot formation and rooting. Nodular calli were induced from Pinus strobus (PS) embryos by culture in nodular callus induction medium in a 0-, 8- or 16-h photoperiod. Mevalonate kinase activity peaked in nodular calli after three weeks of culture on nodular callus induction medium in a 16-h photoperiod, whereas frequency of nodular callus formation peaked after 4 weeks of culture on nodular callus induction medium in darkness. During adventitious shoot formation, MK activity peaked in shoots derived from dark-grown nodular calli after 3 weeks on bud formation medium, and frequency of shoot formation was highest in dark-grown nodular calli cultured on bud formation medium for 4 weeks. During rooting, MK activity peaked 2 weeks after transfer of adventitious shoots to rooting medium and rooting frequency was highest in adventitious shoots after 3 weeks on rooting medium. Although during nodular callus induction in darkness MK activity was inversely related to frequency of nodular callus formation, MK activity was highly correlated with frequency of shoot formation and with rooting frequency. The observed increase in MK activity preceding rooting suggests that MK could serve as a marker for rooting of white pine shoots in vitro. 相似文献
999.
Long-term effects of enhanced UV-B radiation were evaluated in field-grown and greenhouse-grown Quercus rubra L. (northern red oak), a species with a multiple flushing shoot growth habit. Seeds were germinated and grown in ambient, twice ambient (2x) or three times ambient (3x) biologically effective UV-B radiation from square-wave (greenhouse) or modulated (field) lamp systems for three growing seasons. Greenhouse plants in the 2x treatment had greater heights and diameters during the later part of the first year and into the second year, but by the third year there were no differences among treatments. There were no significant differences in growth among treatments for field plants. Enhanced UV-B radiation did not significantly reduce total biomass or distribution of biomass in either field or greenhouse plants. Net photosynthesis (3x), leaf conductance (2x and 3x) and water-use efficiency (3x) of greenhouse plants were greater in the enhanced UV-B radiation treatments in the second year but unaffected by the treatments in other years. None of the treatments affected these parameters in field plants. Dark respiration was increased by the 3x treatment in the first and third years in greenhouse plants, and by the 2x treatment during the second year in field plants. Enhanced UV-B had variable effects on apparent quantum yield and light compensation points. Chlorophylls were unaffected by enhanced UV-B radiation in both greenhouse and field conditions. Bulk methanol-extractable UV-absorbing compounds were increased only by the 3x treatment in greenhouse plants during the third year and by the 2x treatment in field plants during the second year. Overall, Q. rubra appears relatively resistant to potentially damaging enhanced UV-B radiation and is unlikely to be negatively impacted even in the predicted worst-case scenarios. 相似文献
1000.
Williams LD Glenn AE Bacon CW Smith MA Riley RT 《Journal of agricultural and food chemistry》2006,54(15):5694-5700
The fungus Fusarium verticillioides infects maize and produces fumonisins. The purpose of this study was to determine the ability of F. verticillioides to produce fumonisins in synthetic and natural soils and their biological availability to maize roots. Maize seeds were inoculated with a pathogenic strain of F. verticillioides (MRC826) and planted in synthetic and three different natural soils. There were statistically significant reductions in stalk weight and root mass and increased leaf lesions in the MRC826-treated seedlings in all soil types. Fumonisins were detected in all of the soils of seedlings grown from MRC826-inoculated seeds. The fumonisin produced in the soils was biologically available to seedlings as demonstrated by the statistically significant elevation of free sphingoid bases and sphingoid base 1-phosphates in their roots. These results indicate that F. verticillioides produced fumonisins in the autoclaved synthetic and natural soils and that the fumonisin produced is biologically available on the basis of evidence of inhibition of ceramide synthase. 相似文献