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41.
1. The pharmacokinetics of pefloxacin and its active metabolite norfloxacin were investigated in chickens after a single oral administration of pefloxacin at a dosage of 10 mg/kg. To characterise the residue pattern, another group of chickens was given 10 mg of pefloxacin/kg body once daily for 4 d by oral route; the tissue concentrations of pefloxacin and norfloxacin were determined at 1, 5 and 10 d after the last administration of the drug. 2. The concentrations of pefloxacin and norfloxacin in plasma and tissues were determined by HPLC assay. The limit of detection for pefloxacin and norfloxacin was 0.03 microg/ml in plasma or microg/g in tissue. 3. The plasma concentration-time data for pefloxacin and norfloxacin were characteristic of a one-compartment open model. The elimination half-life, maximum plasma drug concentration, time to reach maximum plasma drug concentration and mean residence time of pefloxacin were 8.74 +/- 1.48 h, 3.78 +/- 0.23 microg/ml, 3.33 +/- 0.21 h and 14.32 +/- 1.94 h, respectively, whereas the respective values of these variables for norfloxacin were 5.66 +/- 0.81 h, 0.80 +/- 0.07 microg/ml, 3.67 +/- 0.21 h and 14.44 +/- 0.97 h. 4. Pefloxacin was metabolised to norfloxacin to the extent of 22%. 5. The concentrations of pefloxacin (microg/g) 24 h after the fourth dose of the drug declined in the following order: liver (3.20 +/- 0.40) > muscle (1.42 +/- 0.18) > kidney (0.69 +/- 0.04) > skin and fat (0.06 +/- 0.02). Norfloxacin was also detectable in all the tissues analysed except muscle. No drug and/or its metabolite was detectable in tissues except skin and fat 5 d after the last administration. The concentrations of pefloxacin and norfloxacin in skin and fat 10 d after the last dose of pefloxacin were 0.04 +/- 0.02 and 0.03 +/- 0.01 microg/g, respectively. 相似文献
42.
43.
Fractionation by chromatography on Sephadex G-200 of a saline extract of Cysticercus cellulosae scolex antigen yielded three distinct fractions associated with distinct peaks. These fractions were analysed by double immunodiffusion (DID) and immunoelectrophoresis (IEP). The three peaks gave five, four and three antigenic determinants, respectively, by DID with homologous hyperimmune rabbit serum. However, the same serum gave nine antigenic determinants of scolex antigen by DID and 11 components by IEP. The IEP demonstrated seven and five antigenic components in the first two peaks. The first peak gave a stronger reaction in indirect haemagglutination than the others. There were common antigenic components in C cellulosae and C tenuicollis antigens. 相似文献
44.
45.
In order to estimate the role of phosphatases in maintaining the potential bioavailable P pool in soils, water and 0.4 M
NaOH soil extracts were incubated with immobilized acid phosphatase, alkaline phosphatase, phospholipase and nuclease, separately,
and in combinations. Immobilized nuclease at an optimum pH of 7.0 hydrolyzed the most soluble unreactive P (SUP) both in water
and 0.4 M NaOH extracts. The combination of immobilized alkaline phosphatase and nuclease increased the hydrolysis of SUP
at pH 7.0 by up to 61% in 0.4 M NaOH extracts relative to that due to immobilized nuclease alone. The combination of immobilized
acid phosphatase and nuclease, however, did not increase the hydrolysis of SUP in either extract relative to that due to immobilized
nuclease alone. Immobilized alkaline phosphatase and phospholipase increased the hydrolysis of SUP at pH 7.0 by up to 62%
in 0.4 M NaOH extracts relative to that due to immobilized phospholipase alone. Similarly, immobilized acid phosphatase and
phospholipase increased the hydrolysis of SUP at pH 7.0 by up to 49% in 0.4 M NaOH extracts relative to that due to immobilized
phospholipase alone. The similarities in the optimum pH of indigenous phosphatases in soils and the immobilized phosphatases
used in this study, immobilized on positively charged supports, suggests that indigenous phosphatases could be immobilized
on positively charged surfaces in soils.
Received: 17 November 1998 相似文献
46.
KK Thakur GR Pant L Wang CA Hill RM Pogranichniy S Manandhar AJ Johnson 《Zoonoses and public health》2012,59(6):393-400
Japanese encephalitis was recently reported from individuals in the mountain districts of Nepal without travel history to Japanese encephalitis virus (JEV) endemic areas. We performed a cross-sectional study to estimate the seroprevalence of JEV in pigs and subsequently conducted a survey of farmers to identify risk factors associated with seropositivity. In July and August, 2010, 454 pig serum samples were collected and tested by competitive ELISA. Data from a 35-question survey of 109 pig owners were analysed using multivariate logistic regression. Seventy-six (16.7, 95% CI 13.6-20.4) pigs tested positive for anti-JEV antibodies, none of which had been vaccinated against JEV or sourced from JEV endemic areas. Risk factors associated with JEV seropositivity were 'summer abortion', 'wells as a water source', 'urban location', 'reported presence of mosquitoes' and 'lower elevation'. Our results suggest that JEV is likely circulating in the mountain districts of Nepal, and that locally acquired JEV should be considered a risk for residents and travellers in these areas. 相似文献
47.
Kelvin T. Chiong Mona B. Damaj Carmen S. Padilla Carlos A. Avila Shankar R. Pant Kranthi K. Mandadi Ninfa R. Ramos Denise V. Carvalho T. Erik Mirkov 《Plant methods》2017,13(1):106
Background
Several high-throughput molecular genetic analyses rely on high-quality genomic DNA. Copurification of other molecules can negatively impact the functionality of plant DNA preparations employed in these procedures. Isolating DNA from agronomically important crops, such as sugarcane, rice, citrus, potato and tomato is a challenge due to the presence of high fiber, polysaccharides, or secondary metabolites. We present a simplified, rapid and reproducible SDS-based method that provides high-quality and -quantity of DNA from small amounts of leaf tissue, as required by the emerging biotechnology and molecular genetic applications.Results
We developed the TENS-CO method as a simplified SDS-based isolation procedure with sequential steps of purification to remove polysaccharides and polyphenols using 2-mercaptoethanol and potassium acetate, chloroform partitioning, and sodium acetate/ethanol precipitation to yield high-quantity and -quality DNA consistently from small amounts of tissue (0.15 g) for different plant species. The method is simplified and rapid in terms of requiring minimal manipulation, smaller extraction volume, reduced homogenization time (20 s) and DNA precipitation (one precipitation for 1 h). The method has been demonstrated to accelerate screening of large amounts of plant tissues from species that are rich in polysaccharides and secondary metabolites for Southern blot analysis of reporter gene overexpressing lines, pathogen detection by quantitative PCR, and genotyping of disease-resistant plants using marker-assisted selection.Conclusion
To facilitate molecular genetic studies in major agronomical crops, we have developed the TENS-CO method as a simple, rapid, reproducible and scalable protocol enabling efficient and robust isolation of high-quality and -quantity DNA from small amounts of tissue from sugarcane, rice, citrus, potato, and tomato, thereby reducing significantly the time and resources used for DNA isolation.48.
Molecular size distribution and enzymatic degradation of organic phosphorus in root exudates of spring barley 总被引:1,自引:0,他引:1
Seeds from two varieties of spring barley (Prisma and Camorgue) were grown axenically in water. After 14 days, the culture solutions contained organic P substances (about 4 g P per plant) derived from root exudation, representing about 3% of the total P found in the seed. Gel filtration, separated the organic P into two well defined peaks, one with a high molecular weight (>45000 daltons) and the other with a low molecular weight (<500 daltons). The bioavailability of the soluble organic P released was assessed enzymatically and chemically. At the optimum pH of 5.0, phytase and acid phosphatase hydrolysed about 80% and 65%, respectively of the organic P in the exudate after 24 h whereas at the optimum pH of 9.8, alkaline phosphatase hydrolysed up to 40% P after the same length of time. In a pH 5.0 buffer, up to 10% of the organic P was hydrolysed compared with up to 45% in a pH 9.8 buffer. The high molecular weight organic P fraction recovered from the G-75 Sephadex behaved similarly. 相似文献
49.
This paper examines several farmer managed irrigation schemes in the eastern hills of Nepal. The development and management structure of these is considered in order to identify characteristics of successful schemes which could be used in planning future projects. 相似文献
50.
M. M. Unanian A. E. D. Feliciano Silva K. P. Pant 《Tropical animal health and production》1985,17(1):57-62
Summary This study reports the incidence of abscesses in relation toCorynebacterium pseudotuberculosis infection in goats in north-east Brazil. Among 656 goats examined periodically over almost two years 41·6% were found with
superficially palpable abscesses. Most of the infected areas were in the anterior half of the body in front of the pre-scapular
region; the inguinal region formed the other prominent area. Among 486 dead or slaughtered goats, 56 (11·5%) revealed abscesses
in the internal organs. Lungs and epididymis were affected most, liver, spleen, udder and lateropharyngeal nodes were next
in order and kidneys and mediastinal nodes were least affected. Thus the overall incidence of external and internal abscesses
was 28·8%; of all the abscesses 27·7% were due toC. pseudotuberculosis and the rest due to infections ofCorynebacterium pyogenes and several species of streptococci or staphylococci. The growth ofC. pseudotuberculosis-infected and non-infected goats was of the same order and it seems that caseous lymphadentitis is not the cause of much financial
loss in north-east Brazil but in view of its high incidence remedial measures should be considered necessary in regions where
the goat meat industry is likely to become more intensive and important.
Resumen Este estudio informa sobre la incidencia de abscesos en cabras del nordeste de Brasil. Se examinaron 656 cabras periódicamente durante dos a?os, de las cuales 41·6% se encontraron con abscesos superficiales palpables. Las áreas infectadas correspondieron a la mitad anterior del cuerpo, frente a la región pre-escapular y a la región inguinal. De 486 cabras muertas o faenadas, 56 (11·5%) revelaron abscesos en los órganos internos. De estos, los mas afectados, en orden descendente fueron: pulmones, epididimos, hígado, bazo, ubre, nódulos linfáticos faríngeos, ri?ones y nódulos linfáticos mediastínicos. La incidencia general de abscesos externos e internos fue de 28·8%. De todos los abscesos 27·7% se debieron aCorynebacterium pseudotuberculosis y el resto aC. pyogenes y a especies deStreptococcus y Staphylococcus. El crecimiento de cabras infectadas y no infectadas conC. pseudotuberculosis fue similar, lo que sugiere que la linfadenitis caseosa no ocasiona muchas pérdidas económicas en el nordeste de Brasil pero en vista de su alta incidencia medidas de control deben ser consideradas en regiones donde la industria de carne caprina pueda llegar a ser mas intensiva e importance.
Résumé Parmi 656 caprins examinés périodiquement pendant presque deux ans, 41,6 p. 100 ontété trouvés porteurs d'abcès palpables superficiels. Dans la plupart des cas, la zone infectée se trouvait dans la moitié antérieure du corps, à l'avant de la région pré-scapulaire. La région inguinale constituait la deuxième zone la plus infectée. Sur 486 animaux morts ou abattus 56 (11,5 p. 100) ont montré des abcès internes affectant en premier lieu les poumons et l'épididyme. Le foie, la rate la vessie, les ganglions pharyngienslatéraux venaient ensuite dans l'ordre. Les ganglions rénaux et médiastinaux étaient les moins affectés. La incidence des abcesses externes et internes a étè de 28,8 p. 100. Globalement, 27,7 p. 100 des abcès étaient dus àC. pseudotuberculosis. le reste àC. pyogenes et à quelques espèces de staphylocoques et streptocoques. la croissance des caprins infectés ou non parC. pseudotuberculosis était à peu près identique et il semble que la lymphadénite caséeuse n'entra?ne pas beaucoup de pertes financières dans le Nord-Est brésilien mais étant donné sa fréquence élevée, des mesures curatives devraient être considérées comme nécessaires dans les régions où l'industrie de la viande de chèvre a des chances de devenir plus intensive et plus importante.相似文献