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21.
A total of 686 Tiris half-duplex passive injectable transponders (PIT) of two sizes (23 and 32 mm) were randomly injected s.c. in three positions, armpit, ear scutulum, and upper lip, in 343 fattening calves (1 to 3 mo old). Injections were performed by two trained and two untrained operators. Losses and breakages on the farm were recorded at wk 1, 3, 7, 11, and 15 in restrained animals using two types of hand-held transceivers with a stick antenna. Dynamic reading efficiency (DRE) in animals running through a raceway was also evaluated at wk 1 and 3 and monthly until slaughter, using a stationary transceiver working at 137 dB x microV x m(-1) at 3 m. The total number of PIT that fell or broke in the slaughtering line, the location method, and the recovery time were also recorded. Results on the farm showed low breakages on average (0.4%) and differences (P < 0.05) in losses according to position (armpit, 1.7%; ear, 5.2%; and lip, 14.0%). An interaction (P < 0.05) between position x size was observed, and losses were greatest using a 32-mm PIT in the lip. The DRE was affected (P < 0.05) by PIT position and size, and values were greater for the 32-mm PIT in all positions (armpit: 99.9 +/- 0.1 vs 95.8 +/- 4.9%; ear: 93.8 +/- 2.2 vs 81.9 +/- 4.6%; lip: 66.8 +/- 4.9 vs 53.4 +/- 4.7%, respectively, for 32 vs 23 mm). Recovery of PIT in the abattoir was on average 96.7, 96.7, and 99.2% for armpit, ear, and lip, respectively (P > 0.05). Most of the PIT injected in the armpit were recovered by sight or palpation, but 31.9% were recovered after cutting the muscles around the area and 10.7% were recovered on the internal side of the hide, which jeopardized carcass identification. Recovery of PIT injected in the ear was 23.4% in the hide and 76.6% in the auricular muscles of the head. The easiest recovery was in the lip, 8.9% of PIT were located in the hide and 91.1% in the head. Recovery time was affected (P < 0.05) by position: the quickest was lip (27 +/- 2 s), followed by ear (52 +/- 5 s) and armpit (78 +/- 7 s). In conclusion, taking into account retention and reading performances, injection of a 32-mm PIT into the armpit showed the best results on the farm, but a careful and longer recovery was needed in the abattoir. Improvement of recovery methodology and time would be necessary in order to recommend injection of PIT in the armpit instead of in the ear for cattle tracking or monitoring.  相似文献   
22.
Reports on the internationally emerging significance of multiresistant zoonotic Salmonella in animals and man prompted studies to estimate the significance of multiresistant Salmonella enterica subspecies enterica serotype Typhimurium (S. Typhimurium) phage type DT104 of animal origin in Hungary. A collection of 231 strains (primarily of goose, turkey, poultry and porcine origin from the years 1997-1998) was tested for resistance against 7 selected antibiotics (ampicillin, chloramphenicol, enrofloxacin, nalidixic acid, streptomycin, tetracycline and sulphamethoxazole). Strains with resistance against 3 or more were defined as multiresistant. All strains were phage typed using Felix-Callow's S. Typhimurium phage typing system, and 91 of them (suspect DT104) were also typed according to Anderson's definitive typing (DT) system. In this study, 14% of animal strains from 1997-1998 was classified as DT104, for which turkey, pig and duck seemed to be the main carriers, and the multiresistant non-DT104 strains represented a further 6% of this collection. The prevalence of DT104 was highest among strains of turkey origin (50%), followed by strains of pig (29%), chicken (25%), duck (19%), and goose (3%) origin. The other DT104 related phage types (DT12 and U302) were only detected in the case of 4 strains (2 of porcine, and one each of turkey and of goose origin). The DT104 corresponded to the Felix-Callow types 2/3 or 2c/3 in each case, except in the case of 3 turkey strains where they corresponded to type 35/3. Nalidixic acid resistance was detected in all multiresistant turkey strains and in some of other animal origin but none of these strains were resistant to enrofloxacin. A retrospective analysis (based on the above relationship) indicated that S. Typhimurium strains corresponding to DT104 could be present and increase in the Hungarian farm animal population from about 2% to 20% between 1985 and 1990, in a manner similar to the emergence of human DT104, as reported elsewhere (Pászti et al., 2000). The 91 suspect DT104 strains were also tested for plasmid profile and for spvC gene indicating the presence of the large serotype specific plasmid (Ssp). No characteristic plasmid profile could be attributed to S. Typhimurium DT104. The serovar-specific large plasmid was detected by PCR for spvC in 100% of DT104 strains and in 77% of the non-DT104 strains. The virulence of two DT104 strains was tested in orally infected day-old chicks and compared with virulence of 4 non-DT104 strains. Higher colonizing virulence of DT104 strains could be established as compared to the other strains.  相似文献   
23.
The cultural, morphological, biochemical, serological characteristics and antibiotic susceptibility of 25 Rhodococcus equi strains isolated from lungs and lung abscesses of pneumonic foals and 5 R. equi strains isolated from immuno-compromised human patients were examined. All R. equi strains showed common cultural, morphological and biochemical characteristics both with conventional tests and on the basis of their enzyme profile. The R. equi strains examined were resistant to penicillins with the exception of ampicillin, to sulphamethazine and several strains also to sulphamethoxazole-trimethoprim. All strains were susceptible to erythromycin and rifampicin. The strains isolated from humans showed somewhat higher rate of antibiotic resistance to penicillin, cefotaxime, kanamycin, streptomycin, lincomycin, and oxytetracycline. The overwhelming majority (96%) of the equine isolates belonged to serotype 1 in Prescott's serotyping system, while the human isolates could not be serotyped.  相似文献   
24.
ABSTRACT Unmodified and low water activity (a(w))-tolerant cells of Candida sake CPA-1 applied before harvest were compared for ability to control blue mold of apples ('Golden Delicious') caused by Penicillium expansum under commercial storage conditions. The population dynamics of strain CPA-1 on apples were studied in the orchard and during storage following application of 3 x 10(6) CFU/ml of each treatment 2 days prior to harvest. In the field, the population size of the unmodified treatment remained relatively unchanged, while the population size of the low-a(w)-modified CPA-1 cells increased. During cold storage, the populations in both treatments increased from 10(3) to 10(5) CFU/g of apple after 30 days, and then declined to about 2.5 x 10(4) CFU/g of apple. In laboratory studies, the low-a(w)-tolerant cells provided significantly better disease control as compared with the unmodified cells and reduced the number of infected wounds and lesion size by 75 and 90%, respectively, as compared with the non-treated controls. After 4 months in cold storage, both unmodified and low-a(w)-tolerant cells of C. sake were equally effective against P. expansum on apple (>50% reduction in size of infected wounds).  相似文献   
25.
Hohmann J  Forgo P  Szabó P 《Fitoterapia》2002,73(7-8):749-751
Investigation of the alkaloid fraction of the bulbs of Hymenocallis x festalis yielded a new natural product, 3-methoxy-8,9-methylenedioxy-3,4-dihydrophenanthridine (1). The structure was elucidated on the basis of spectroscopic data.  相似文献   
26.
Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. Black locust plants are commonly produced by two methods, by seed and by root cuttings. Tissue culture propagation can be considered as a relatively new method. Growing trees from seed is a relatively simple method for reliably producing seedlings on a large scale under a variety of circumstances. Mechanization of the method is easy and the production cost is relatively low. Propagation from root cuttings and tissue culture are valuable for reproduction of superior individuals or varieties. By applying these methods, superior traits of the selected trees can be preserved in the clones. Recent experiments demonstrated that micropropagated trees could be successfully transplanted into soil, hardened and grown in the field. Biography: Karoly Redei (1952), male, doctor, deputy director general of Hungarian Forest Research Institute H-1023 Budapest, Frankel Leó Str. 42 44, HUNGARY. Responsible editor: Chal Ruihai  相似文献   
27.
28.
Procyanindin extract (PE) is a mixture of polyphenols, mainly procyanidins, obtained from grape seed with putative antiinflammatory activity. We evaluated the PE effect on RAW 264.7 macrophages stimulated with lipopolysaccharide plus interferon-gamma that show a rapid enhanced production of prostaglandin E2 (PGE2) and nitric oxide (NO). Our results demonstrated that PE significantly inhibited the overproduction of NO, dose and time dependently. PE caused a marked inhibition of PGE2 synthesis when administered during activation. Moreover, PE pretreatment diminished iNOS mRNA and protein amount dose dependently (10-65 microg/mL). PE (65 microg/mL) pretreatment inhibited NFkappaB (p65) translocation to nucleus by nearly 40%. Trimeric and longer oligomeric-rich procyanidin fractions from PE (5-30 microg/mL) inhibited iNOS expression but not the monomeric forms catechin and epicatechin. Thus, we show that the degree of polymerization is important in determining procyanidin effects. PE was considerably a more effective inhibitor of NO biosynthesis (IC50 = 50 microg/mL) in comparison to other antiinflammatories, such as aspirin (3 mM), indomethacin (20 microM), and dexamethasone (9 nM). In conclusion, PE modulates inflammatory response in activated macrophages by the inhibition of NO and PGE2 production, suppression of iNOS expression, and NFkB translocation. These results demonstrate an immunomodulatory role of grape seed procyanidins and thus a potential health-benefit in inflammatory conditions that exert an overproduction of NO and PGE2.  相似文献   
29.
A sensitive and specific method is described for the simultaneous determination of oxytetracycline, tetracycline (TC), and chlortetracycline residues in edible swine tissues, by combining liquid chromatography with spectrofluorometric and mass spectrometry detection. The procedure involved a preliminary extraction with EDTA-McIlvaine buffer acidified at pH 4.0, followed by solid-phase extraction cleanup using a polymeric sorbent. The liquid chromatography analysis was performed with spectrofluorometric detection after postcolumn derivatization with magnesium ions. The limits of quantification were 50 microg/kg for muscle and 100 microg/kg for kidney tissues. The recovery values were greater than 77.8% for muscle and 65.1% for kidney. The method has been successfully used for the quantification of tetracyclines in swine tissues samples. The selective liquid chromatography mass spectrometric analysis for confirmation of oxytetracycline in one positive swine muscle sample was made by atmospheric pressure chemical ionization (APCI). The APCI mass spectra of the TCs gave the protonated molecular ion and two typical fragment ions, required for their confirmation in single ion monitoring scan mode in animal tissues.  相似文献   
30.
The aim of the present study was to determine the relationship of progesterone (P4), bovine pregnancy-associated glycoprotein-1 (bPAG-1) and nitric oxide (NO) levels with late embryonic (LEM; day 28 to day 42) and early fetal mortalities (EFM; > day 42 to day 56) in dairy cows. Transrectal ultrasonography (6–8 MHz) was performed in 100 Holstein-Friesian cows at days 28, 42 and 56 after artificial insemination (AI; day 0) to diagnose pregnancy and to monitor the fate of the embryo. After ultrasound scanning of each cow, a milk sample was collected for assessment of P4 by an ELISA test and a blood sample was collected for assessment of bPAG-1, by using a double-antibody radioimmunoassay, and serum NO metabolites (nitrate + nitrite). Based on ultrasonographic examinations and bPAG-1-RIA, 41 of 100 inseminated cows were confirmed pregnant at day 28 after AI. Nine cows suffered of LEM, and 6 cows suffered of EFM and the overall pregnancy loss rate was 36.6% (15/41) between days 28 and 56 of pregnancy. By logistic regression analysis, there were no significant relationships between the level of P4 and bPAG-1 at day 28 after AI and the occurrence of LEM and EFM. Also, there were no significant relationships between the levels of P4 and bPAG-1 at day 42 and the occurrence of EFM. On the other hand, a significant relationship (P<0.05) was found between NO level at day 28 and the occurrence of LEM. In conclusion, measurement of the serum NO concentration at day 28 of pregnancy might help to predict the outcome of pregnancy by day 42 in dairy cows but further studies are needed to confirm this.  相似文献   
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