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131.
132.
Daniel J. Burba DVM Michael A. Collier DVM Lawrence E. Default PhD Olivia Hanson-Painton PhD Harold C. Thompson Jr. Claude L. Holder 《Journal of Equine Veterinary Science》1993,13(12):696-703
The uptake and distribution of intramuscularly (IM) administered tritium-labeled polysulfated glycosaminoglycan (3H-PSGAG) in serum, synovial fluid, and articular cartilage of eight horses was quantitated, and hyaluronic acid (HA) concentration of the middle carpal joint was evaluated in a pharmacokinetic study. A full-thickness articular cartilage defect, created on the distal articular surface of the left radial carpal bone of each horse served as an osteochondral defect model. 3H-PSGAG (500 mg) was injected IM, between 14 and 35 days after creation of the defects. Scintillation analysis of serum and synovial fluid, collected from both middle carpal joints at specific predetermined times up to 96 hours post-injection, revealed mean 3H-PSGAG concentrations peaked at 2 hours post-injection. 3H-PSGAG was detected in cartilage and subchondral bone 96 hours post-injection in samples from all eight horses. There were no statistically significant differences in 3H-PSGAG concentration of synovial fluid or cartilage between cartilage defect and control (right middle carpal) joints.
HA assay of synovial fluid revealed concentrations significantly increased at 24, 48, and 96 hours post-injection in both joints. The concentration nearly doubled 48 hours post-injection. However, no statistically significant differences were found between synovial concentrations of HA in cartilage defect and control joints.
3H-PSGAG administered IM to horses, was distributed in the blood, synovial fluid, and articular cartilage. HA concentrations in synovial fluid increased after IM administration of polysulfated glycosaminoglycan. 相似文献
133.
Abstract. Usual residue-management options are to remove the residue, use it as mulch with or without undercutting or to incorporate it into the soil. While the role of surface mulch in evaporation has been widely studied, the information on the effect on evaporation of mulch with undercutting or residue incorporated into soil, particularly in relation to soil type and evaporativity (Eo) is lacking. We studied the effect of wheat straw used in various ways on the course of evaporation loss from soil columns with three soils at Ludhiana, India and one soil at Bushland, Texas, USA, under two Eo's Energy-limited evaporation rates under mulch (Eom) followed the soil-specific relation Eom/Eo= a e(bRes+cEo), where Res is residue rate t/ha and a, b and c are constants; Eo, is expressed in mm/d. In an effort to model the total evaporation (CE) during the energy-limited stage ‘U’ was obtained from appropriate CE versus time curves and (CE-U) was regressed over (t - ti)0.5 to obtain the slope ‘α’ (Ritchie 1972) for the soil-limited evaporation stage. The observed ‘U’ was independent of mulch rate and Eo but was strongly affected by soil type, Values of ‘α’ decreased with increase in mulch rate and decrease in Eo and coarseness of soil. The otherwise short lived benefit of evaporation reduction with mulch per se, which peaked after a few days was maintained when residue was mixed with soil at the stage when evaporation reduction reached a maximum; this benefit continued for several weeks. Cumulative evaporation values computed from ‘U’ and ‘α’ agreed closely with the observed values under straw mulch for loamy sand and clay loam soils and for ‘undercut’ and ‘residue mixed’ treatments on all soils regardless of Eo, and for all situations under small Eo. However, for sandy loam and silt loam soils under Eo of 10 mm/d, the modified square root of the time function of Jalota et al. (1988) gave a better fit. 相似文献
134.
The determination of differentiation and transplantation antigens will be of growing importance in immune diagnosis for individual animals as well as for breeding purposes in populations. Differentiation antigens characterize subsets of cell populations and indicate their functional capacity while transplantation antigens represent markers of individuals of a species. Occurrence and significance of these antigenic systems are briefly reviewed. 相似文献
135.
A M Hoffman 《Veterinary Clinics of North America: Equine Practice》2001,17(2):335-49, viii
Respiratory diagnostic instruments previously available only to referral centers should be converted into miniature, portable, wireless medical devices for use in practice. Internet and wireless connections of these instruments should expedite the process of seeking second opinions and in general information sharing. We are moving into a world of greater objectivity that should free us from speculation in some areas, yet open new avenues for research and innovation in others. 相似文献
136.
137.
Abstract— In a blinded trial to determine the efficacy of potentiated sulfa drugs in the treatment of canine pyoderma, 50 dogs with superficial pyoderma were randomly assigned to receive either once or twice daily trimethoprim-sulfadiazine (30mg.kg-1) or once daily sulfadimethoxine-ormetoprim (55mg.kg-1 on the first day, then 27.5 mg.kg-1 thereafter). Dogs were evaluated prior to antibiotic therapy. Clinical efficacy of the antibiotic was assessed after 3 weeks of antibiotic therapy and, if needed, after 6 weeks of antibiotic therapy. Forty-five dogs completed the study; 43 dogs were used in the statistical analysis. The percentage of dogs that were cured of their pyoderma with once daily trimethoprim-sulfadiazine was 38.5% by 3 weeks and 75.9% by 6 weeks. With twice daily trimethoprim-sulfadiazine, 57.1 and 78.6% of dogs were cured by 3 and 6 weeks, respectively. With once daily sulfadimethoxine-ormetoprim, 75.0 and 100% of dogs were cured by 3 and 6 weeks, respectively. This difference was not statistically significant, possibly due to the low sample size. Few adverse effects were noted. Résumé— Dans une étude en double aveugle pour apprécier l'efficacité des sulfamides potentialisés dans le traitement des pyodermites canines, cinquante chiens présentant une pyodermite superficielle ont reçu, au hasard, soit deux fois ou une fois par jour du triméthoprime-sulfadiazine (30 mg.kg-1) ou une fois par jour du sulfadiméthoxine-ormétoprime (55mg.kg-1 le premier jour, puis 27.5 mg.kg-1). Les chiens ont étéévalués avant le traitement. L'efficacité clinique de l'antibiotique a été appréciée après 3 semaines de traitement et, si besion est, après 6 semaines. Le pourcentage de chiens guéris avec une prise quotidienne de triméthoprime-sulfadiazine était de 33.5%à 3 semaines et 75.9%à 6 semaines. Avec des prises biquotidiennes de triméthoprime-sulfadiazine 57.1% et 78.6% des chiens étaint guéris à 3 et 6 semaines. Avec une prise quotidienne de sulfadiméthoxine-ormétoprime, 75.0% et 100.0% des chiens étaient guéris à 3 et 6 semaines. Cette différence n'était pais statistiquement significative, probablement à cause de la taille trop faible de l'échantilon. Très peu d'effects secondaires ont été notés. Zusammenfassung— Für eine Blindstudie zur Bestimmung der Wirksamkeit von potenzierten Sulfonamidpräparaten bei der Behandlung kaniner Pyrodermie wurden 50 Hunde mit oberflächlicher Pyodermie zufällig ausgewählt, um entweder einmal oder zweimal täglich Trimethoprim-Sulfadiazin (30mg/kg) oder einmal täglich Sulfadimethoxin-Ormetoprim zu erhalten (55 mg/kg am ersten Tag, danach 27,5 mg/kg). Die Hunde wurden vor der antibotischen Therapie untersucht. Die klinische Wirksamkeit der Antibiose wurde nach 3 Wochen antibiotischer Therapie und, wenn nötig, nach 6 Wochen antibiotischer Therapie ausgewertet. 45 Hunde durchliefen die Studie vollständig; 43 Hunde fanden in die statistische Analyse Eingang. Der Prozentsatz der Hunde, deren Pyrodermie durch einmal tägliches Trimethoprim-Sulfadiazin geheilt wurde, lag bei 38,5% nach 3 Wochen und bei 75,9% nach 6 Wochen. Bei zweimaliger Trimethoprim-Sulfadiazin-Verabreichung wurden 57,1% und 78,6% der Hunde nach 3 bzw. 6 Wochen geheilt. Mit einer einmal täglichen Verabreichung von. Sulfadimethoxin-Ormetoprim wurden 75,0% und 100% der Hunde nach 3 bzw. 6 Wochen geheilt. Dieser Unterschied war statistisch nicht signifikant, möglicherweise aufgrund der geringen Fallzahlen. Es wurden nur wenige Nebenwirkungen festgestellt. Resumen A cincuenta perros que presentaban pioderma superficial se les evaluó para la eficacia de antibioticos potenciados de tipo sulfamídico en el tratamiento del pioderma canino, por medio de la administración de una a dos veces diarias de trimetoprim-sulfadiazina (30 mg/kg), o sulfadimetoxinaormetoprim una vez al día (55 mg/kg en al primer día, y 27.5 mg/kg después de la primera dosis). Los animales se examinaron antes del tratamiento con antibióticos. La eficacia clínica del tratamiento se evaluó a las tres o seis semanas en los casos necesarios. Cuarenta y cinco de los perros completaron el estudio; 43 se utilizaron en analisis estadísticos. El porcentaje de perros curados con el tratamiento diario a base de trimetoprim-sulfadiazina fué del 38.5% a las 3 semanas, y 75.9% a las 6 semanas. De los animales tratados dos veces al día con trimetoprim-sulfadiazina, el porcentaje de cura fue del 57.1% y 78.6%, a las 3 y 6 semanas respectivamente. Con el tratamiento a base de sulfadimetoxina-ormetoprim una vez al día, 75.0% y 100% de los perros fueron curados a las tres y seis semanas. La diferencia no se encontró estadísticamente significativa, posiblemente debido al reducido número de perros evaluados. Se observaron posas reacciones adversas a la medicación. 相似文献
138.
Field experiments were conducted at Tamil Nadu Rice Research Institute, Aduthurai, India, during the wet seasons of 1992 and 1993 to study the effect of full and partial substitution of fertiliser N with green manure N (Sesbania rostrata) on nitrogen uptake, yield attributes and yield of rice. The experiment consisted of eight treatments with two levels of N (100 and 200 kg ha−1 ) and three sources of N application viz., fertilizer, integrated (1:1 fertilizer and green manure N) and green manure N compared to the recommended practice (150 kg fertilizer plus 6.25 t ha−1 (72 kg N) green manure) and a no N control. Nitrogen application markedly increased the N uptake. Combined use of the two N sources at 200 and 222 kg N ha−1 and of single fertilizer N at 200 kg N ha−1 recorded the maximum N uptake, increased the yield attributes such as number of panicles per unit area, weight per panicle, number of total and filled grains per panicle and test weight. At 200 kg N ha−1 full substitution of N by green manure reduced the grain yield but only partial substitution of N by green manure resulted in almost similar yield as single fertilizer N. Thus 200 kg N ha−1 applied in equal proportions of fertilizer and green manure N can be recommended for medium duration rice cultivars. 相似文献
139.
There is only limited information on sheep interferon available. Recent publications have reported on: 1. an interferon (IFN) alpha subtype, which is secreted by the fetal trophectoderm into the lumen of the uterus between the 10th and 21st day of gestation. It was therefore named ovine trophoblast protein (oTP-1), and is responsible for signalling pregnancy to the ewe via high affinity receptors in the endometrium. It is thought that oTP-1 acts by directly influencing prostaglandin metabolism. 2. the role of lentivirus-induced interferon (LV-IFN) in the pathogenesis of Maedi/Visna. The results indicate that LV-IFN limits viral replication and therefore contributes to virus persistence and is also responsible for a chronic inflammatory process. 3. the mitogen- or antigen-dependent induction of ovine interferon gamma (IFN gamma) and its characterization. 相似文献
140.