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1.
Plant Foods for Human Nutrition - The purpose of this study was to compare the yield, chemical composition, antimicrobial and antioxidant properties of essential oils isolated from leaves of Laurus...  相似文献   
2.
Bobwhite quails were treated with imazalil for 8 weeks. The fungicide was given admixed in the food at 0, 100, 300, 500 and 1000 mg kg?1. Even at the highest dose tested, imazalil did not affect the liver weight or the hepatic microsomal protein content. In treated quails, no significant induction of cytochrome P-450 or NADPH-cytochrome c-reductase activity was observed. Furthermore, imazalil did not induce or inhibit 7-ethoxyresorufin or 7-ethoxycoumarin O-deethylase in quail microsomes. Only a slight but significant increase by 35% and 49% in aniline hydroxylase activity was measured for the 500- and 1000-mg kg?1 dose levels, respectively. After a drug-free period of one week, aniline hydroxylase activity returned to control values, indicating that the effect was fully reversible. It is concluded that imazalil does not induce or inhibit drug-metabolizing enzymes in the quail, even at doses which exceed by far the maximum levels currently used to dress seed under field conditions (100 mg kg?1).  相似文献   
3.
Latency sites and reactivation of duck enteritis virus   总被引:16,自引:0,他引:16  
Shawky S  Schat KA 《Avian diseases》2002,46(2):308-313
Duck virus enteritis (DVE) is a contagious disease caused by herpesvirus in waterfowl populations. Recovered birds become carriers and shed the virus periodically. Reactivation of latent duck enteritis virus (DEV) has been implicated in outbreaks of DVE in domestic and migrating waterfowl populations. In this study, the sites for virus latency were determined in white Pekin ducks infected with the DEV-97 strain. At 3 wk postinfection, infectious virus was not detectable in tissues or cloacal swabs (CSs). At 7 and 9 weeks postinfection, the viral DNA was detected by polymerase chain reaction in the trigeminal ganglia (TG), suggesting that the virus is latent. Viral DNA was detected in the peripheral blood lymphocytes (PBL), spleen, thymus, bursa, and CSs only after in vitro cocultivation. In vivo virus reactivation was demonstrated when dexamethasone or a combination of dexamethasone and cyclophosphamide was inoculated in latently infected ducks. The reactivation of DEV occurred without any clinical evidence of the disease, but the virus was detected in PBL and CSs. We conclude from this study that DEV establishes latency in TG and lymphoid tissues including PBL.  相似文献   
4.
Molecular Variability of the Capsid Protein of the Prune Dwarf Virus   总被引:2,自引:0,他引:2  
Sequences of the capsid protein gene and the preceding intergenic region of eleven isolates of prune dwarf virus from central Europe were determined. The isolates were obtained from plum, cherry and peach trees. Comparison of all sequenced isolates (including two sequences published previously) revealed high (88%) conservation of the capsid protein gene. The highest degree of identity was observed in the C-terminal half, where only 13 amino acid substitutions could be observed in contrast to the N-terminal half with 22 substitutions. No reasonable correlation between amino acid substitutions and host species and/or geographic origin of the isolates was observed. Alignment with capsid protein genes of other ilarviruses revealed apple mosaic virus, elm mottle virus, lilac ring mottle virus and prunus necrotic ringspot virus as the most related to prune dwarf virus. Unlike the isolates of related prunus necrotic ringspot virus all the isolates of prune dwarf virus shared extensive conservation of the intergenic region. Portions of RNA3 were selected for design of universal primers for PCR detection.  相似文献   
5.
A desexed female ferret was presented with bilateral alopecic changes. Clinical examination revealed generalized alopecia and abdominal distension. A polycystic mass was found behind the right kidney, and the whole abdomen was filled with a large turgid mass. Radiography and ultrasonography confirmed the presumptive diagnosis of a hydrometra. Hematology and serum biochemistry showed regenerative anemia with light azotemia. Laparotomy showed the presence of a neoplastic mass at the location of the right ovary, a massive enlargement of the uterus filled with a clear fluid, and a subcapsular cyst on the left kidney. After surgery, histopathologic examination of the tissues diagnosed a leiomyoma of the right ovary with hyperplasia of the uterine wall.  相似文献   
6.
The effect of the extreme drough of 1976 has been studied to obtain information on the reaction of the vegetation of moorland pools following a fall in the ground water level. The degree of change appeared to be dependent on the nutrient status of water and soil and on the relief. The vegetation of metatrophic and guanotrophic moorland pools showed the most drastic change.  相似文献   
7.
Zosima absinthifolia (ZA) extracts and the coumarins (+)-columbianadin and (-)-deltoin were evaluated for their potential hepatoprotective and antiinflamatory effects in a CCl(4)-induced hepatotoxicity assay in rats and by the inhibition of TNF-α production on LPS-stimulated THP-1 macrophages, respectively. Both the ZA extracts and the coumarins showed hepatoprotective activity confirmed by monitoring the ALT/AST levels and by histopathological examination. The antiinflamatory activity, proved by the inhibition of TNF-α production, was found to be higher for the n-hexane root extract than for coumarins, suggesting synergic potential of the extract. The concentration of (-)-deltoin and (+)-columbianadin in extracts was determined by HPLC analysis.  相似文献   
8.
In neurons, individual dendritic spines isolate N-methyl-d-aspartate (NMDA) receptor-mediated calcium ion (Ca2+) accumulations from the dendrite and other spines. However, the extent to which spines compartmentalize signaling events downstream of Ca2+ influx is not known. We combined two-photon fluorescence lifetime imaging with two-photon glutamate uncaging to image the activity of the small guanosine triphosphatase Ras after NMDA receptor activation at individual spines. Induction of long-term potentiation (LTP) triggered robust Ca2+-dependent Ras activation in single spines that decayed in approximately 5 minutes. Ras activity spread over approximately 10 micrometers of dendrite and invaded neighboring spines by diffusion. The spread of Ras-dependent signaling was necessary for the local regulation of the threshold for LTP induction. Thus, Ca2+-dependent synaptic signals can spread to couple multiple synapses on short stretches of dendrite.  相似文献   
9.
10.
Extracellular products in culture filtrates of Aeromonas salmonicida subsp. achromogenes and Vibrio anguillarum isolated from infected fish have been shown to possess skin inflammatory factor. The extracellular products from Vibrio anguillarum were cytotoxic in HeLa and CHO cells. In addition to the skin lesions, the culture filtrates of V. anguillarum caused necrotic reaction on the rabbit skin. Five of 6 strains of V. anguillarum were lethal to mice after intraperitoneal administration of 3×107 CFU. Only 1 strain of 5 A. salmonicida subsp. achromogenes produced extracellular products which elicited cytotoxic effects in the CHO cells. None of the A. salmonicida subsp. achromogenes strains were lethal to mice. The cytotoxins were inactivated when heated at 65°C for 30 min. The results indicate that the thermolabile exotoxins are non-enterotoxic since they failed to stimulate fluid accumulation in the rabbit ileal loop and did not cause elongation of the CHO cells. The rounding off of CHO cells, as well as of HeLa cells indicate that the exotoxins may play an important role in fish diseases.  相似文献   
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