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181.
Calicivirus was isolated from the joint of a kitten that had pyrexia, upper respiratory tract disease, and severe shifting-limb lameness. Marked mononuclear inflammation was found in the synovial fluid. Calicivirus infection or live-virus vaccination previously had been associated with arthropathy, but virus had not been recovered from affected joints. Calicivirus infection should be considered as a diagnosis in kittens with fever and arthralgia, especially if there is a history of recent vaccination or upper respiratory tract disease. Lameness associated with calicivirus infection may be severe, but appears to be self-limiting and is associated with an excellent prognosis for recovery.  相似文献   
182.
Eight bovine hearts with lesions of eosinophilic myositis (EM) and 2 bovine hearts without EM lesions were collected at slaughter. Blood samples from these 10 hearts, and the heart of a newborn calf also were collected. Histologically, Sarcocystis cruzi was identified in the 8 hearts with EM lesions and the 2 hearts without EM lesions, but not in the heart of the newborn calf. Serum was harvested from the 10 blood samples and was used in homologous, modified, passive cutaneous anaphylaxis tests. Antigen was prepared from S cruzi bradyzoites isolated from the 2 hearts without EM lesions. Serum samples from the 8 cattle with EM lesions reacted positively to S cruzi antigen. When heat-inactivated IgE in serum (56 C for 4 hours) was used, all passive cutaneous anaphylaxis responses were considered negative. Using ELISA, serum IgE concentrations from the 10 cattle with and without EM lesions were 2.2 to 9 U/ml. As determined by radial immunodiffusion, IgM concentrations were 80 to 215 mg/dl. Immunoglobulin G concentrations were 420 to 2,050 mg/dl, but most were less than or equal to 1,700 mg/dl. Immunoglobulin A concentrations were 0 to 62 mg/dl; 1 steer with EM lesions had 0 mg/dl. Double-gel immunodiffusion confirmed the presence of Sarcocystis-specific precipitating antibodies. Sera from the 10 cattle with and without EM lesions formed at least 1 precipitin band.  相似文献   
183.
The first regulations on plant protection in Germany date from the last century and the first basic rules from 1937. New legislation was published in 1968. The key basis for modern plant protection is the Plant Protection Act of 1986. The legal basis, organization and scope of legislation i n the tield of plant protection in Germany are dcscrihed. The specific role of the rederal German states (Linder) is pointed out. The competent authority for granting authorization o f plant protection products in Germany is the Federal Biological Research Centre for Agriculture and Forestry in Braunschweig. The maximum period of authorization is 10 years. The legal basis for placing plant protection products on the market within the Member States of the European Union is summarized. together with the main elements of the regulations regarding authorization of plant protection products. There is a need for international cooperation to overcome foreseeable problem and workload regarding risk reduction in plant protection.  相似文献   
184.
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   
185.
A field experiment was conducted during the winter seasons of 1992–93 and 1993–94 at Anand to study the effect of FYM, nitrogen and source of fertilizer on growth and yield of mustard [ Brassica juncea (L.) Czernj & Cosson]. The results showed significant variation in leaf area index (LAI), crop growth rate (CGR), dry matter production and seed yield. The direct effect of farmyard manure (FYM) was conspicuous in improving the growth of mustard. FYM application at 10 tonnes ha−1 significantly increased the LAI, CGR and dry matter accumulation per plant at almost all the stages during first year study (1992–93) and in pooled analysis. Similarly, nitrogen application registered maximum LAI, CGR at 75 kg level and RGR and NAR at 50 kg level at almost all the during both years. Sulphur carrying source (Ammonium sulphate plus single super phosphate) increased all stages growth characters. Maximum dry matter accumulation per plant and seed yield were recorded with highest levels of FYM (20 tonnes ha−1), N (75 kg ha−1) and source having S. Seed yield was strongly associated with LAI and dry matter accumulation per plant at all the stages.  相似文献   
186.
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   
187.
Canine liposarcoma   总被引:1,自引:0,他引:1  
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188.
189.
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   

190.
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   
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