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141.
In a flock of sheep to which food with excess copper (= Cu) had been fed for some months 39 animals died of chronic copper toxicosis. In 5 sheep of this flock the plasma concentrations of the enzymes glutamate dehydrogenase (GLDH), sorbitol dehydrogenase (SDH), aspartate-amino-transferase (ASAT) and copper were measured several times over a period of 100 days. At day 23, 58 and 97 needle biopsies of the liver were taken. The biopsies were used for histological examination and Cu-analysis. After 100 days the sheep were slaughtered and chronic copper poisoning was diagnosed by raised Cu concentration and typical histological alterations in the liver. The activities of GLDH and SDH in the plasma of the 5 sheep were consistently above normal, ASAT activity and the plasma Cu level were raised only occasionally. The results of Cu determination in biopsy samples were of little predictive value compared with post mortem Cu analysis of the liver.  相似文献   
142.
143.
Abstract. In Australia, stubble burning and tillage are two of the major processes responsible for the decline of soil organic carbon concentration in cropped soils, and the resulting soil degradation. However, the relative importance of these two practices in influencing the soil organic carbon concentration and the long-term impact on soil quality and productivity are not clear. The effects of stubble burning as practised by farmers in southeastern Australia were evaluated in two field trials, one of 19 years duration, the other of 5 years. Conventional tillage (three tillage passes) led to greater loss of soil organic carbon than stubble burning. Loss of total soil organic carbon attributed to stubble burning in the 0–10 cm layer was estimated to be 1.75 t C ha−1 over the period of the 19-year trial, equivalent to 29% of that lost due to tillage. In the 5-year trial, no change in soil organic carbon due to stubble burning was detectable. Changes in soil quality associated with stubble burning detected in the longer trial included a reduction in macro-aggregate stability, and increases in pH and exchangeable K+. Only the latter two were detected in the shorter trial. A higher mean wheat yield (average 0.15 t ha−1) following stubble burning was observed in the 19-year trial but not in the 5-year trial. Research to monitor the longer term effects of stubble burning is needed, and to identify conditions where loss of soil organic carbon is minimized.  相似文献   
144.
We report on an outbreak of enzootic abortion in a herd of goats with high losses caused by mixed infection with Coxiella burnetii and Chlamydia psittaci. Both agents could be detected by microscopic investigation of smears from afterbirths by Giménez staining and by a capture enzyme-linked immunofluorescence assay (Capture ELIFA). Additionally, Coxiella burnetii was isolated from the same tissues in BGM cell cultures. Serological investigations with CF, indirect ELIFA, and IF tests revealed high antibody titers against both agents in most animals. Coxiella antigen was still detected 91 days later in milk samples of two infected goats by Capture ELIFA.  相似文献   
145.
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   
146.
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   
147.
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   
148.
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   
149.
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   
150.
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   
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