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211.
Use of Echinococcus granulosus worm antigens for immunodiagnosis of E. granulosus infection in dogs.
Echinococcus granulosus worm excretory/secretory antigens (WES) were used in ELISA for diagnosis of E. granulosus infection in dogs and compared with protoscolex somatic antigens (PSM). Sera from 224 dogs were tested. There was no correlation between ELISA absorbance values and E. granulosus worm burdens using either antigen. There was a significant linear relationship between absorbance values of sera tested in the ELISA using WES (W-ELISA) and the ELISA using PSM (P-ELISA). However, there was a small but significant difference between the absorbance values of the sera tested against the two antigens. Western blot analysis of WES using sera from E. granulosus-infected and uninfected dogs revealed antigenic components of relative molecular mass (Mr) larger than 94,000, Mr 94,000-68,000 and Mr 43,000-39,000 in worms, and these were specific for E. granulosus and not identified in PSM; these antigenic differences may be responsible for differences in reactivity in ELISA. The sensitivities of W-ELISA and P-ELISA were 80.8% and 75.6%, respectively. The specificities of W-ELISA and P-ELISA were 93.7% and 97.9%, respectively. The reduced specificity in W-ELISA was mainly attributable to increased background reactivity of sera from Taenia hydatigena-infected dogs. Despite the reduction in specificity, both ELISAs are valuable epidemiological tools to determine the prevalence of antibody to E. granulosus in dog populations and to monitor the success of hydatid control campaigns. 相似文献
212.
213.
1118 Friesian cows and 101 Friesian heifers were investigated in internal pelvic measurements and their relationships to external measurements. The mean of the pelvic vertical and the medium diagonally diameter of the pelvis are 19.8 cm and 18.3 cm. 363.9 square centimetres and 76.3 centimetres were found for the pelvic surface and pelvic circumference. The difference between the biggest and smallest pelvis was 295.0 square centimetres. Medium to high coefficiences of correlation were detected between the internal pelvic measurements but relationships between internal and external pelvic measurements were low. From determined external pelvic measurements only the hip breadth provides usefull informations of the pelvic shape. 相似文献
214.
J. Gonzalez-Soriano E. Rodriguez-Veiga P. Martinez-Sainz S. Mayayo-Vicente P. Marin-Garcia 《Anatomia, histologia, embryologia》1995,24(1):61-65
As in the number of mammals, the most prominent feature of the ganglion-cell layer in the retina of the German shepherd dog is the sharp increase in the density of ganglion cells in the central area. There is an area of maximum density and also a ‘cat-like’ visual streak, located dorsal to the optic disc. The isodensity lines of ganglion-cell distribution is roughly concentric. Their values vary from 5300-13 000 cells/mm2 in the central area, with the cells densely packed, to 1000 cells/mm2 or less in the periphery, where the cells are sparsely distributed. There were some individual differences amongst the animals studied, although all of them were pure-bred dogs. This suggests that the configuration of the retina in the canine species is not only dependent on the breed itself but also on some other parameters such as phylogenetic heritage, environment, aptitude, lifestyle, or even training. 相似文献
215.
DANNY W. SCOTT 《Veterinary dermatology》1995,6(2):75-78
Résumé— Une analyse rétrospective clinicopathologique a été menée chez 100 chiens présentant une hydradénite suppurative diagnostiquée par biopsie cutanée. Aucune prédisposition d'âge, de race ou de sexe n'a été mise en évidence. Tous les chiens présentaient cliniquement une folliculite bactérienne, ou une furonculose, ou les deux, qu'elle soit primaire ou secondaire à d'autres dermatoses. Aucene lésion clinique n'était pathognomonique d'hidradénite suppurative. Chez 73 chiens, l'hidradénite suppurative était associée microscopiquement à des degrés variables d'inflammation du follicule pileux. Chez 27 chiens, l'hidradénite suppurative était la seule évidence histologique d'inflammation annexielle. L'observation histopathologique d'hidradénite suppurative suggère l'existence sur le plan clinique d'une folliculite bactérienne, d'une furonculose, ou des 2. [Scott, D.W. Suppurative inflammation of apocrine sweat glands (suppurative hidradentis) in the dog: a retrospective clinicopathological analysis of 100 cases (inflammation suppurative des glandes sudorales apocrines (hidradénite suppurative) chez le chien: une analyse rétrospective clinicopathologique de 100 cas). Resumen— Se llevó a cabo un estudio clinicopatológico retrospectivo en 100 perros con hidradenitis supurativa diagnosticada mediante biopsia cutánea. No se detectó predominancia alguna de raza, sexo o edad. A todes los perros se les habia diagnosticado clinicamente foliculitis o furunculosis bacteriana, o ambas, ya sea de forma primaria o secundaria a otras dermatosis. No se encontraron lesiones clinicas especificas indicativas de hidradenitis supurativa. En 73 animales, la hidradenitis supurativa estaba asociada con varios grados de inflamación folicular a nivel microscópico. En los 27 casos restantes, los anejos presentaban unicamente hidradenitis supurativa. La presencia de hidradenitis supurativa a nivel microscópico sugiere la existencia de foliculitis o furunculosis bacteriana clinicas, o de ambas. [Scott, D.W. Suppurative inflammation of apocrine sweat glands (suppurative hidradenitis) in the dog: a retrospective clinicopathological analysis of 100 cases (inflamación supurativa de las glándulas sudoriparas apocrinas (hidradenitis supurativa) en el perro: estudio clinicopatológico retrospectivo de 100 casos). Abstract— A retrospective clinicopathological study was conducted on 100 dogs with suppurative hidradenitis as determined by skin biopsy. No apparent age, breed, or sex predilections were recognized. All dogs had been given a clinical diagnosis of bacterial folliculitis, furunculosis, or both of these, whether primary or secondary to other dermatoses. There were no clinical lesions that uniquely suggested the presence of suppurative hidradenitis. In 73 dogs, suppurative hidradenitis occurred in conjunction with varying degrees of hair follicle inflammation microscopically. In 27 dogs, suppurative hidradenitis was the only histological evidence of adnexal inflammation. The histopathologic finding of suppurative hidradenitis suggests the existence of clinical bacterial folliculitis, furunculosis, or both of these. 相似文献
216.
L. Pülschen 《Journal of Agronomy and Crop Science》1992,168(4):249-254
Mixed cropping of leguminous underseed species and cereal crops may increase productivity and serve some additional purposes. Two leguminous weed species which are widely distributed in annual crops of the Ethiopian highlands have been studied with varying coverage in greenhouse trials in Ethiopia with regard to their suitability as underseeds and with wheat ( Triticum turgidum [L.] Thell. var. durum [Desf.] MacKey) as a main crop. The competitive effects of Scorpiurus muricatus L. on the grain yield of wheat were smaller than those of Medicago polymorpha L. (-14.1 % and -23.6 % respectively, compared with the underseed free control) which is mainly ascribed to differences in their speed of development and shoot height. The residual effects of the underseed's root masses on the grain yield of the successive teff crop (Eragrostis tef [Zucc] Trotter) were significantly higher with Scorpiurus muricatus (+99.3 %) than with Medicago polymorpha (+63.6 %). The results are discussed with regard to the specific site conditions in the cereal-dominated cropping systems of the Ethiopian highlands. 相似文献
217.
L G Rickard G L Zimmerman E P Hoberg P W Lockwood D W Weber R Miller 《Veterinary parasitology》1989,33(2):125-133
The effectiveness of the morantel sustained release trilaminate (MSRT) in controlling gastrointestinal nematodes through a grazing season was evaluated using 60 yearling beef stocker calves randomly divided into 2 groups of 30 animals each. In April 1985, the calves comprising the treatment group each received an MSRT designed to release morantel tartrate continuously for 90 days while those of the control group remained unmedicated. All animals were weighed and samples of rectal feces were taken at 14-day intervals, beginning on Day 0, until trial termination (Day 168). At trial termination, 10 control and 10 treated calves were necropsied for recovery of gastrointestinal nematodes. Three sets of parasite-na?ve tracer calves were utilized to evaluate the initial, interim and final levels of pasture contamination by nematode larvae. Overall, the use of the MSRT resulted in a 75.5% reduction (P less than 0.001) in output of nematode eggs from the principals, an 81.8% reduction (P less than 0.001) in numbers of gastrointestinal nematodes in principals (at trial termination), and a 96.9% reduction (P less than 0.05) of pasture larval nematode contamination (as indirectly indicated by parasite burdens in tracer calves). The mean weight advantage of treated calves was 16.6 kg per head (P less than 0.001). 相似文献
218.
Germinating seeds and young plants of winter rape var. Górczañski were vernalized for 56–63 days under conditions of 9-hour day, at the temperature 2 and 5 °C and in continuous darkness at the temperature 2 °C. After vernalization the plants grew under conditions enabling to complete vernalization: in a glass-house at the temperature day/night 15/10 °C and in semi natural conditions of open vegetation hall in the period from June till August. After sub-optimal vernalization further growth of the plants at lowered temperature increased its effectiveness (completion of vernalization). Depending on the degree of the vernalization of the plants the completion of their vernalization was both obligatory, i.e. conditioning the acquisition of the ability of generative development, and facultative i.e. accelerating this development. It has been demonstrated that the population of plants of the examined variety is strongly differentiated not only with respect of vernalization requirements in the particular plants, but also what regards the effectiveness of vernalization completion. New observations have been made indicating that the mechanisms controlling the successive phases of generative development, i.e. phase of forming flower buds and the flowering phase are not identical which may be interpreted as indicating that the "flowering factor" is polymorphous. 相似文献
219.
D E Granstrom R K Ridley Y Baoan L J Gershwin P M Nesbitt L A Wempe 《American journal of veterinary research》1989,50(4):571-574
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
220.
K. SEMB 《Weed Research》1996,36(4):353-367
As a part of a broader study, two experiments were carried out in growth chambers with three day/night temperature regimes (10/7, 20/14 and 30/21^C) studying growth characteristics of individual seedlings over a four-week period. Experiment 1 was performed with spring barley (Hordeum vulgare L.), Galeopsis tetrahit L., and Viola Arvensis Murray. Experiment 2, with three irradiance levels at 20/14^C, and one irradiance level at the other temperatures, was performed with spring barley, V. arvensis, Chenopodium album L., Brassica rapa L. sspoleifera (DC.) Metzger, and Stellaria media (L.) Vill. Leaf area, dry weight, relative growth rate, net assimilation rate, and net photosynthetic rate generally showed an optimum at 20/14^C. Increasing irradiance resulted in a decreased specific leaf area. Expressed as fraction of shoot dry weight, green leaves decreased and stems, flowers, and yellow leaves increased with increased time, irradiance, and temperature. At all temperatures, barley, B. rapa and G. tetrahit had the largest dry weights, but at 20/14^C. C album and S. media and at 30/21^C C. album also had large values. Differences in dry weight between species correlated more to morphological features than to assimilation rate. 相似文献