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101.
SUMMARY: Free radical oxidation products, namely conjugated dienes, ultraviolet fluorescence (excitation 325 nm, emission 395 nm) and visible fluorescence (excitation 360 nm, emission 460 nm) were measured in equine synovial fluid exposed to free radicals In vitro and in the plasma and synovial fluids of horses with synovial effusions. The synovial effusions were induced by intra-articularly administered carrageenin (0.3 ml, 1%), which rarely resulted in clinical lameness. The free radicals were generated In vitro by mixtures of iron and ethylene diamine tetra acetate (Fe/EDTA) or mixtures of hypoxanthine and xanthine oxidase (HX/XO). The conjugated diene concentrations and intensity of ultraviolet fluorescence were negligible in plasma and synovial fluid specimens. No increase resulted from incubation of synovial fluids with either a free radical generating system or as a result of the induced inflammation. The intensity of visible fluorescence did not increase in specimens incubated with Fe/EDTA. However, the intensity of visible fluorescence increased in specimens incubated with HX/XO, in synovial effusions induced by carrageenin, in plasma and in synovial fluids aspirated from saline injected controls. The results indicate that the intensity of visible fluorescence of equine synovial fluid increases after exposure to free radicals and during synovitis in the horse, suggesting a possible role for free radicals in the pathogenesis of equine inflammatory joint diseas  相似文献   
102.
103.
The availability of cow ovaries from the slaughterhouse has been very limited in Taiwan. To maximize the use of cow ovaries for research purposes, whole ovary dissection was performed and the developmental competence of the oocytes derived from different sizes of follicles was assessed by the rates of in vitro maturation (IVM) and parthenogenetic activation of the oocytes in Experiment 1 (Exp 1). Cumulus-oocyte complexes (COCs) derived from small (1-2 mm) and large (3-8 mm) follicles were subjected to standard IVM culture for 24 h. Mature oocytes were selected and then parthenogenetically activated using A23187 (5 microm, 5 min) or thimerosal (200 microm, 10 min) alone or combined with 6-dimethylaminopurine (2.5 mm and 3.5 h, respectively). Activation rates of the oocytes, neither from the large nor small follicles, were affected by different activation treatments (single or combined stimuli). Whereas maturation rates for the oocytes from large follicles were superior to those from small follicles in both the single (59% vs 45%) and combined treatments (76% vs 40%; p < 0.05). To understand how prolonged heat shock (HS) influences cytoskeletal configurations of mature bovine oocytes, in Experiment 2 (Exp 2), matured oocytes derived from large follicles were randomly allocated to different durations of HS treatments at 41.5 degrees C for 0 (C0h, control, n = 12), 1 (HS1h, n = 28), 2 (HS2h, n = 31), and 4 h (HS4h, n = 30). An additional control group was cultured for 4 h without HS (38.5 degrees C, 4 h, n = 35). Alterations in nuclear structures, microtubules (MTs), and microfilaments (MFs) of the oocytes were examined. Abnormalities in the chromosomes, spindle MTs and the percentages of oocytes with cytoplasmic MTs increased with time of HS treatment. The intensity of the MF distribution in the HS oocytes was also altered. Significant changes in the cytoskeleton after HS may be associated with the reduced development under hyperthermia and, perhaps, with the low pregnancy rates of the animals during hot seasons.  相似文献   
104.
This retrospective study examined the case records of Old World screw-worm fly myiasis in dogs in Hong Kong's New Territories. Myiasis due to OWSWF was identified and treated in 59 dogs at our clinic over a period of 1 year. Signalment, causes of initial wound, and treatments implemented, are reported. All cases recovered from myiasis with a combination of larvae removal and wound debridement, antibiotics, and topical and systemic insecticides. Whilst this parasite is currently exotic to Australia, much of the country is environmentally suitable (tropical and subtropical) for establishment of OWSWF.  相似文献   
105.
The Glutaraldehyde test (GT), a rapid and inexpensive test, has been utilized empirically for many years in bovine practice for diagnosing inflammatory diseases. GT is used primarily to demonstrate increased serum concentrations of fibrinogen and globulin. Glutaraldehyde binds with free amino groups in fibrinogen and immunoglobulin to create a clot in a first degree chemical reaction. The clotting time of the GT estimates the content of proteins produced in response to inflammation. The applicability of GT for diagnosing inflammation in the horse has never been investigated. The objective of this study was to determine the ability of GT to distinguish between acute and chronic inflammatory disease in horses. Thirty-seven horses with suspected inflammatory diseases were evaluated using the GT, history, complete clinical examination and routine blood analysis. GT-times, laboratory results and clinical outcome were compared statistically. Horses that were determined to be acutely affected (based on history, clinical examination and routine blood analysis) tended to have a negative GT (75%). Results of the GT did not correlate with blood fibrinogen concentration. Positive GT also predicted a fatal outcome in 69% of the clinical cases. The results of this trial indicate that GT can be a useful screening test to distinguish between acute and chronic inflammatory disease in horses.  相似文献   
106.
The long-term effect of different depths of soil cultivation on weed seedling emergence from naturally occurring populations of weed seeds in the soil was examined in four experiments on land previously in pasture, raspberry canes or intensive vegetable production. At approximately monthly intervals, weed seedlings were counted and then killed with contact herbicides, after which plots were cultivated to 250 or 10mm, or were left undisturbed. The treatments were continued for 7 years. One experiment was then discontinued whilst the previously uncultivated plots on the other three were cultivated to 150 mm at approximately monthly intervals for a further 4 years in one experiment, and for 8 years in the other two. After the first year, very few seedlings emerged in the uncultivated and shallow cultivated plots, and seedling numbers declined slowly in the deep-cultivated plots. Under repeated deep cultivation, seedling emergence of almost all species declined exponentially. Different species declined at different rates, with Rubus idaeus L., Plantago lanceolata L., Veronica arvensis L. and Ranunculus spp. being the most rapidly declining group. Rates of decline for individual species were similar to those observed in Europe.Juncus bufonius L. behaved differently from the other species, and showed no decline in seedling numbers. In the initial 7-year period, 28 000 weed seedlings per m?2 emerged from the deep-cultivated plots on soil previously cropped with vegetables. Over the same period, less than 11 000 seedlings emerged in shallow-cultivated plots, and just over 4000 in uncultivated plots. In the second phase of the experiments, fewer seedlings of most species emerged than in the first phase, and the decline in numbers of Coronpous didymus (L.) Sm. seedlings was slower. Résumé Les effets à long terme de différentes profondeurs de travail du sol sur la levée des mauvaises herbes ont étéétudiés sur des populations naturelles dans des parcelles dont les précédents étaient: paturage, framboisier ou maraichage intensif. À des intervalles d'environ un mois, les jeunes plantes de mauvaises herbes étaient dénombrées puis détruites à l'aide d'herbicides de contact, aprés quoi les parcelles étaient travaillées sur 250 ou 10 mm, ou laissées sans intervention. Cette premiére phase a duré 7 ans. Une expérience a alors été arretée et les parcelles précédemment non cultivées des trois autres ont été travaillées à une profondeur 150 mm, à des intervalles d'environ un mois pendant 4 ans dans un expérience, et pendant 8 ans dans les deux autres. Aprés un an, trés peu de mauvaises herbes levaient dans les parcelles non cultivés et dans celles travaillées superficiellement, et le nombre de levées diminuait lentement dans les parcelles travaillées profondément. Lá oú le travail profond était répété, les levées de presque toutes les especes declinaient exponentiellement. Les différentes espéces déclinaient à des vitesses différentes,Rubus idaeus L., Plantago lanceolata L., Veronica arvensis L. et Ranunculus spp. déclinant le plus rapidement. Les vitesses de diminution pour les differentes espéces étaient similaires à celles observées en Europe. Juncus bufonius L. se comportait différemment des autres espéces et ne montrait aucune décroissance du nombre de levées. Au cours de la période initiale de 7 ans, 28 000 mauvaises herbes par m?2 levaient dans les parcelles maraicherés travaillées profondément. Au cours de la meme periode, moins de 11000 mauvaises herbes lavaient dans les parcelles travaillées superficiellement et un peu plus de 4000 dans les parcelles non travaillées. Dans la seconde phase de I'expérience, on observait moins de levées de la plupart des especes que au cours de la premiére et la decroissance du nombre de levés de Coronpous didymus (L.) Sm. était moins rapide. Einfluβ der Bodenbearbeitung auf Keimung und Populationsdynamik von Unkrautern Der langfristige Einfluβ verschieden tiefer Bodenbearbeitung auf die Keimung von Unkrautern aus der naturlich gegebenen Samenbank im Boden wurde in 4 Versuchen auf Flachen untersucht, die vorher als Weide oder mit Himbeer oder intensiven Gemusekulturen genutzt worden waren. Die Keimpflanzen wurden 7 Jahre lang etwa monatlich ausgezahlt und mit Kontaktherbiziden abgetotet, danach wurden die Parzellen 25 tief 15 cm, tief oder gar nicht bearbeitet. Ein Versuch wurde beendet, wahrend eine der 3 ubrigen unbearbeiteten Parzellen fur weitere 4 Jahre und die anderen beiden fur weitere 8 Jahre in etwa monatlichen Abstanden 15 cm tief bearbeitet wurden. Am Ende des ersten Jahres liefen auf den unbearbeiteten und den flach bearbeiteten Flachen sehr wenige Keimpflanzen auf; auf den tief bearbeiteten Flachen nahm die Zahl der Keimpflanzen langsam ab. Bei wiederholt tiefer Bodenbearbeitung verringerte sich die Zahl der Keimpflanzen fast aller Arten exponentiell. Am schnellsten sank die Keimrate bei Rubus idaeus L., Plantago lanceolata L., Veronica arvensis L. und Ranunculus spp. Die Abnahme der Keimrate war bei den einzelnen Arten ahnlich wie in Europa beobachtet. Juncus bufonius L. verhielt sich von den anderen Arten abweichend und lieβ keine Abnahme der Keimrate erkennen. In der anfanglichen 7-Jahres-Periode keimten auf den vorher gemusebaulich genutzten, tief bearbeiteten Flachen 28000, den flach bearbeiteten weniger als 11 000 und den unbearbeiten gut 4000 Samen m?2. In der 2. Versuchsphase wurden bei denmeisten Arten weniger Keimpflanzen als in der 1. beobachtet, und die Abnahme der Keimrate von Coronopus didymus (L). Sm. war langsamer.  相似文献   
107.
In vivo ovum pick-up (OPU) in sheep may be improved with a proper choice of aspiration elements (needle and tubing) and aspiration vacuum pressure. In the present study, two experiments were carried out. In Expt 1, visible follicles in ovaries of slaughtered ewes (treated separately according to their diameters: small<3 mm, medium 3-5 mm and large>5 mm) were aspirated using different combinations of the three studied factors such as aspiration flow rate (10, 20, 30, 40 and 50 ml water/min), needle gauge (18 and 20 G) and tubing inner diameter (1, 2 or 3 mm internal diameter). In Expt 2, a study with two 18 G needles of different lengths (18 G: 82 mm; 18 GL: 600 mm) was carried out, using ovaries obtained post-mortem, and performing in vivo laparoscopic follicular aspiration on ewes. We considered good quality oocytes as those with both complete compact cumulus and a homogeneous cytoplasm. Recovery rate, proportion of good quality oocytes (good quality oocytes/100 oocytes recovered) and overall efficiency (good quality oocytes/100 follicles aspirated) were noted. In Expt 1, aspiration flow rate affect remarkable proportion of good quality oocytes (69.5%, 50.5%, 44.8%, 36.5% and 28.3% for flows from 10 to 50 ml/min respectively, p<0.05). Needle gauge did not affect aspiration device efficiency. Thin and intermediate tubings were more effective (overall efficiency rates: 34.9%, 32.3% and 28.1% for 1, 2 and 3 mm respectively, p<0.05). Follicle size did not affect recovery rate, but proportion of good quality oocytes was higher for large (77.9%) and medium (64.4%) follicles (p<0.05). Finally, some combinations of the aspiration device showed greater effectiveness. In Expt 2, needle length did not influence recovery rate, but good quality oocytes rate was significantly modified both post-mortem and in vivo (good quality rate for 18 G vs 18 GL needles: 69.5% vs 47.7% and 58.1% vs 25.4%, post-mortem and in vivo respectively, p<0.05). We conclude that low-aspiration flow rates (10 and 20 ml/min) with thin or intermediate tubings (1 and 2 mm), and any short needle (18 G or 20 G) are the most adequate aspiration factors for OPU in sheep.  相似文献   
108.
109.
A glasshouse experiment was carried out to investigate the influence of increasing levels of nitrogen and phosphorus on the growth of six common weed species growing alone or in competition with spring barley (Hordeum vulgare). Capsella bursa‐pastoris, Chenopodium album, Papaver rhoeas, Sinapis arvensis, Spergula arvensis, Viola arvensis and spring barley were grown in pots with different levels of nitrogen (0, 30, 60, 90, 120 and 150 kg N ha?1) or phosphorus (0, 10, 20, 30, 40 and 60 kg P ha?1). The aboveground parts of the plants were harvested after 7 weeks and the dry weight of shoots, percentage N and P content of the shoot and uptake of N and P were determined. A linear or a polynomial model was used to describe the data. Growing alone, Spergula arvensis was the only weed species that increased its dry weight at the same rate as barley. Weed species with low dry weight increase had larger increases in percentage N or P content than barley, indicating a luxury accumulation of nutrients. The uptake of N and P per pot did not differ much between weeds and barley. V. arvensis and P. rhoeas accumulated least nutrients (per cent of dry matter) and Spergula arvensis accumulated most. Weeds grew poorly in competition with barley. The percentage N and P content in barley did not change when they grew in competition with weeds.  相似文献   
110.
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