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61.
A review on the biology, epidemiology, pathogenesis and diagnosis of Otodectes cynotis in dogs and cats is presented. Additionally, three cases of generalized otodectic mange in dogs are described. 相似文献
62.
H. STANJEK J. W. E. FASSBINDER H. VALI H. WÄGELE W. GRAF 《European Journal of Soil Science》1994,45(2):97-103
The occurrence of greigite (Fe3S4) in soils is reported for the first time. It forms irregularly-shaped aggregations within plant cells in the Gr2 horizon of a gley soil developed from colluvial material. Greigite was identified by X-ray diffraction and magnetic measurements and was investigated by optical and transmission electron microscopy. Biogenic formation is proposed, based on the elongated shape of single greigite crystals, and sulphur isotope analyses, which showed a depletion in 34S relative to the soil-water sulphate. The cell-edge length of 0.98639±0.00003 nm is significantly smaller than values reported for sedimentary greigite. The mean coherence length of 27 nm agrees with TEM observations and indicates that the single greigite crystals lie in the superparamagnetic region. However, the fine aggregates show magnetically single-domain behaviour. Greigite is the only carrier of a stable magnetic remanence in the soil profile studied. 相似文献
63.
G W Almond 《Veterinary Clinics of North America: Food Animal Practice》1992,8(3):503-515
The majority of sows return to estrus within 2 weeks after weaning. Swine practitioners attempt to optimize production by reducing the WEI. Some sows fail to resume estrous cyclicity after weaning; however, the endocrinologic pathogenesis of these anestrous sows is speculative. The average WEI is influenced by numerous factors, including season, environmental temperature, photoperiod, nutrition, stress, facility design, lactation length, and management practices. It is evident that the majority of these factors have a more profound influence on primiparous sows than on multiparous sows. Optimum protein and energy consumption by sows during lactation and after weaning and effective utilization of breeding facilities reduce the WEI. The precise roles of photoperiodic changes, elevated environmental temperatures, and stress in seasonal infertility remain poorly understood. Fortunately, current management techniques have reduced the WEI on most farms without instituting therapeutic measures. 相似文献
64.
Abstract— Cell mediated and humoral immune responses to experimental Trichophyton verrucosum infection were assessed by sequential cutaneous biopsies, antibody assessments and microscopic monitoring of fungal presence. Histopathologic examination showed the accrual of lymphocytes and other inflammatory cells in the dermis of infected sites. Immunoperoxidase staining of frozen sections with monoclonal antibody preparations revealed an influx of macrophages, BoCD4+ and B0CD8+ lymphocytes and γδ T cells from the 5th day to the 33rd day of infection. A moderate influx of B cells was observed. Protein G-colloidal gold staining revealed the presence of immunoglobulins in the dermis and superficial epidermal layers. Trichophyton specific serum antibodies appeared between days 33 and 55. Microscopic assessment of infected tissues revealed an increase in T, verrucosum elements (mycelium and ectothrix spores) from days 19 to 55. Fungal elements in infected areas did not decrease until after both humoral and cell mediated elements of the immune response were established. These responses imply a combination of cell mediated and humoral events were associated with T. verrucosum immunity and clearance in the calf. Résumé— Le réponse immunitaire humorale et cellulaire a une infection expérimentale àT. verrucosum a été appréciée par des biospsies cutanées successives, des dosages d'anticorps et la recherche microscopique de champignons. L'examen histopathologique a montré un afflux de lymphocytes et d'autres cellules inflammatoires dane le derme des sites infectés. Les marquages en immunopéroxydase par un anticorps monoclonal de coupes congelées a montré un influx de macrophages, lymphocytes BoCD4+ et BoCD8+ et des cellules T γδ, du 5e au 33e jour de l'infection. Un marquage par une protéine G—or colloidal a révélé d'immunogolglobulines dans le derme et les couches supéerficielles de l'épiderme. Les anticorps spécifiques de Trichophyton sont apparus entre 33 et 55 jours. L'examen microscopique des tissus infectés a révélé une augmentation du nombre d'éléments de T. verrucosum (mycelium et spores ectothrix) du 19e au 55e jours. Les éléments fongiques dans les zones infectées n'ont pas diminué avant que les réponses humorales et cellulaires ne solent établies. Ces résponses impliquent qu'une coopération des réponses humorales et cellulaires étaient associées dans l'immunité et la défense contre T. verrucosum. Zusammenfassung— Die zellvermittelten und humoralen Immunantworten auf die experimentelle Infektion mit T. verrucosum wurden durch eine Serie von Hautbiopsien, Antikörperuntersuchungen und mikroskopischer Untersuchung auf das Vorhandensein von Pilzen ausgewertet. Die histopathologische Untersuchung zeigte eine Ansammlung von Lymphozyten und anderen Entzündungszellen in der Dermis der infizierten Stellen. Die Immunperoxidasefärbung der Gefrierschnitte mit monoklonalen Antikörperzubereitungen zeigte einen Influx von Makrophagen, BoCd4-und BoCD8-Lymphozyten und gamma-delta-T-Zellen vom 5. bis zum 33. Tag der Infektion. Es wurde auch ein mäßiger Influx von B-Zellen beobachtet. Die Protein-G-kolloidale Goldfärbung zeigte die Anwesenheit von Immunglobulinen in der Dermis und den oberflächlichen epidermalen Schichten. Trichophyton-spezifische Serumantikörper traten zwischen Tag 33 und 55 auf. Die mikroskopische Untersuchung infizierter Gewebe zeigte eine Zunahme von T. verrucosum-Bestandteilen (Myzel und exktothrixe Sporen) vom Tag 19 bis 55. Pilzteile in infizierten Bereichen verminderten sich weder, nachdem humorale, noch nachdem zellvermittelte Elemente der Immunantwort auftraten. Diese Reaktionen deuten an, daß eine Kombination von zellvermittelten und humoralen Vorgängen im Zusammenhang mit T. verrucosum-Immumtät und Abheilung beim Kalb vorliegt. Resumen Por medio de biposias cutáneas secuenciales, medida de anticuerpos y exámen microscópico de presencia de hongos, se estudió la respuesta inmunitaria de tipo humoral y celular producida por la infección experimental con T. verrucosum. El exámen histopatológico reveló la presencia de agregación de linfocitos y otras células inflamatorias procedentes de la dermis de los puntos infectados. La tintura por medio de inmunoperoxidasa de las secciones congeladas, con preparaciones monoclonales de anticuerpos, demostró un aflujo de macrófagos BoCD4 + y BoCD8 + linfocitos y linfocitos, Tαδ, desde el quinto hasta el día 33 la infección. También se observó un aflugo moderado de linfocitos B. La tintura aúrica de proteina coloidal G reveló la presencia de inmunoglobulinas en al dermis y capas superficiales de la epidermis. Los anticuerpos específicos para la especie Trichophyton aparecieron entre los días 33 y 55. El exámen microscópico de los tejidos afectados demostró un incremento, de los elementos füngicos T. verrucosum (micelio y esporas exótricas) desde los días 19 al 55. Los elementos fúngicos en áreas infectadas no disminuyeron hasta después del establecimiento de ambos tipos de respuesta inmunitaria, humoral y celular. Estas respuestas implican que la combinación de ciertos fenómenos de inmunidad celular y humoral, están relacionados con la desaparición y la inmunidad de la infección producia por T. verrucosum en el ternero. 相似文献
65.
G Plassiart J F Guelfi J P Ganiere B Wang G Andre-Fontaine M Wyers 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(6):443-453
Twenty rabbits were inoculated with a suspension of Viral Hemorrhagic Disease virus. Hemostatic functions were assessed every sixth hour from 6 to 60 hours post-inoculation. Tissue samples obtained at the same intervals allowed the study of the development of lesions throughout the experiment. Biological signs of Disseminated Intravascular Coagulation (DIC) were detected on and after 30 h post-inoculation and consisted of prolonged One Stage Prothrombin Time and Activated Partial Thrombin Time, the decrease of factors V, VII, and X and high levels of soluble fibrin monomer complexes and D-dimers. A reduction of thrombocyte numbers, heterophils and lymphocytes was associated. The close association of DIC and necrotizing hepatitis lesions suggested the hepatic lesions to be the most important DIC triggering factor. Other mechanisms are discussed. 相似文献
66.
Two mungbean varieties, Guj-1 and PIMS-1 differing in their productivity potential, were examined to investigate their photosynthetic system at various stages of growth in relation to yield with two different dates of sowing. Vertical leaves were found to be beneficial. On the other hand, excessive leaf area during the later stages of growth may be detrimental to yield. Lower LAD at seedling stage and overall high NAR values may be reflected in higher grain yield. NAR declined as season progressed and this, in turn, may be related with increase in LAI. The grain yield was considerably more at the first date of sowing as compared to second date of sowing, the effect was being more pronounced in var. PIMS-1 . Various environmental factors recorded at two different dates of sowing and at various stages of growth indicated that these factors may have influenced the yield potential at two different dates of sowing. 相似文献
67.
Chloroform-methanol (2:1 v/v), absolute methanol, and 90% acetone were evaluated for their effectiveness as extractants of chlorophyll a from samples of phytoplankton communities collected from catfish ponds. Chloroform-methanol consistently extracted more chlorophyll a than either 90% acetone or methanol. Precision for the methanol extraction was also unacceptably low, with an average coefficient of variation of 17%. Average coefficients of variation for the chloroform-methanol and 90% acetone extraction procedures were 6 and 5%, respectively. Filtered samples should be steeped in chloroform-methanol for at least 4 h to obtain maximum chlorophyll extraction, and the addition of MgCO3 to the extractant as a buffer is not necessary. 相似文献
68.
Response time of broiler chickens to cimaterol: meat tenderness, muscle composition fiber size, and carcass characteristics. 总被引:4,自引:0,他引:4
The response time to cimaterol (CIM), a beta-adrenergic agonist, by broiler chickens for carcass characteristics, muscle composition, muscle fiber size, catheptic enzyme activity, and tenderness was determined. Two trials were conducted in which chickens were fed a control diet (CON) containing 0 ppm of CIM or a diet containing 1 ppm of CIM. Trial 1 consisted of 55, 31-d-old broiler chickens individually fed for up to 48 h. At 0, 6, 12, 18, 24, and 48 h, five CON and five CIM-fed chickens were killed. Trial 2 consisted of 160, 33-d-old broiler chickens group-fed for up to 14 d. At 2, 4, 6, 8, 10, 12, and 14 d, 10 CON and 10 CIM-fed chickens were killed. The breast muscle (BM) and leg muscle (LM) weight, cathepsin B and L activities, DNA, RNA, and protein concentration, and BM shear force value (SFV) were measured in both trials. Thigh muscle (TM) SFV were measured in Trial 2 only. Fiber size of BM was measured (five birds per treatment) at d 2, 6, 10, and 14. In Trial 1, BM weight and SFV were lower in CIM-fed birds at 6 h (P less than .05). In Trial 2 BM SFV were higher at d 8 (P = .06) and d 10 (P less than .05) in CIM-fed chickens. The SFV of CIM-fed chickens were higher at d 4, 8, 10, 12, and 14 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
69.
In a nine-year-old female cat, the diagnostic procedure, therapy and differential diagnoses of a rare, primary, malignant, epibulbar melanoma are presented. Post-operatively no recidivation or metastases occurred within 18 months. 相似文献
70.
With the help of a new synthetic material follicles and corpora lutea from the ovaries of 80 cows in different stages of the sexual cycle were examined for modifications of their blood vessel architecture. In the theca externa the main artery which runs towards the follicle, separates into arterioles of which capillaries derive in the theca interna, building a basket-like network around the zona granulosa. After ovulation the follicle wall forms characteristic fields. Capillaries grow into the zona granulosa and thus the folds form the lobular structure of the corpus luteum. Capillaries which rise from the ruptured part of the follicle, spread centripetally and together with lutein cells they build up the not lobulated cupola of the corpus luteum. The regression of the corpus luteum starts around the 16th day of the cycle, beginning at the capillary network of the cupola. A contraction of the vessels and a quick decrease of the volume follow. 相似文献