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排序方式: 共有423条查询结果,搜索用时 15 毫秒
91.
92.
The acute toxicity for sheep of 3 alkaloids that occur in Phalaris acquatica was examined by intravenous and oral administration. The lowest tested dose rates that produced clinically observed signs were, for 5-methoxy dimethyltryptamine, 0.1 mg/kg body weight intravenously and 40 mg/kg orally; for gramine, 10 mg/kg intravenously and 500 mg/kg orally; and for hordenine, 20 mg/kg intravenously and 800 mg/kg orally. All induced the clinical signs observed in the nervous form of phalaris toxicity, but none induced the cardiac, sudden death, syndrome. 相似文献
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G. Koptopoulos M. Papanastasopoulou O. Papadopoulos H. Ludwig 《Comparative immunology, microbiology and infectious diseases》1988,11(3-4):199-205
Previous preliminary studies had shown that caprine herpesvirus (BHV-6) infections exist in many countries where goats play an economical role. The extensive serum survey made in Greece reveals that the virus must be widespread because more than 50% of the goats have antibodies. The bucks were found to have a higher evidence of infections than the female goats. The kids possessing maternal antibodies became seronegative at the age of 4 months and new antibodies appeared at the age of 7–8 months. Observations in 2 closed goat herds showed that the virus does not spread during the mating and lactating period. Neutralization titres increased or new infections in seronegative animals occurred after the summer when breeding took place. The virus is present in a latent state and recurrent infections are assumed to occur. In spite of that all our efforts to isolate the virus were unsuccessful, even after experimental immunosuppression. 相似文献
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97.
ANC Castro MC Díaz GJ Mendoza‐Torres CA Llerena‐Zavala MD Ghezzi CG Barbeito 《Reproduction in domestic animals》2018,53(3):655-666
The breeding of South American camelids is the main economic activity of the high Andean region of South America and it, is potentially, the most profitable resource in of the Puna environmental conditions of the Puna. The duration of the gestation in alpaca is 339.7 ± 12 days. The objective of the present work was to macroscopically and microscopically describe the ontogenic development of the splanchnic cavities of the alpaca and to determine the gestational time in which the post‐cranial ossification centers are observed in the embryos/fetuses of this species, from day 21 to 107 of gestation. The documentation of normal ontogenic development, which is vacant for this period, is of the utmost importance to understand the consequences of the alterations at the different gestational times, as well as for the estimation of the gestational age in the case of abortions. Forty‐seven alpaca specimens of both sexes, at different times of their gestational development, collected during slaughter at local slaughterhouses of the Department of Huancavelica, Peru, were evaluated. Specimens were assigned to seven groups according to their morphological characteristics. The embryogenesis in the alpaca was characterized by a series of changes comparable to those occurring in other mammals with similar gestational periods. Despite these similarities, species differences were found in some organs as stomach, which are observed too in adult individuals. 相似文献
98.
João CA. Alves Ana MMP. dos Santos Ângelo DP. Fernandes 《Veterinary anaesthesia and analgesia》2018,45(1):123-128
Objective
To evaluate the feasibility and effectiveness of mesotherapy in dogs compared with a positive control group.Study design
Experimental, randomized, blinded study.Animals
Fifteen working police dogs with chronic back pain.Methods
Animals were divided randomly into control (CG; n = 5) and treatment groups (TG; n = 10). A combination of 140 mg lidocaine, 15 mg dexamethasone and 20 mg thiocolchicoside was administered to group TG along with a 70-day course of a placebo, administered as if it was carprofen. Carprofen was administered to Group CG for 70 days, at a dose adjusted to their weight. On day 0, an intradermal injection of Ringer’s lactate was also administered. Both groups were rested for 3 days and resumed normal activity over a 5-day period. Response to treatment, measured by the Canine Brief Pain Inventory (CBPI) and the Hudson Visual Analogue Scale (HVAS), was evaluated before treatment (T0), after 15 days (T1) and 1 (T2), 2 (T3), 3 (T4), 4 (T5) and 5 (T6) months. Results were compared using a Mann–Whitney test or a paired samples t test.Results
When comparing CBPI results, no differences were found between groups TG and CG at T0 through T3 and in T6 and T7. Differences were observed in CBPI sections after the discontinuation of carprofen: at T4 [p = 0.02 for Pain Interference Score (PIS) and p = 0.03 for Pain Severity Score (PSS)] and T5 (p = 0.16 for PIS and p = 0.03 for PSS), with group TG having overall better results. Individual treatment results were considered successful in one dog of group CG (20%), whereas in group TG, success was higher (ranging from 78% at T1 to 22% at T7). No significant differences were registered with the HVAS.Conclusions and clinical relevance
Mesotherapy may be a promising treatment option for canine musculoskeletal-related pain. Further studies are required. 相似文献99.
Ludwig K. Simon 《Journal of pest science》1966,39(6):89-91
Zusammenfassung Technisch reines Malathion mit 96% Wirkstoffgehalt kann mit Flugzeugen in einer Aufwandmenge von 0,3–1,2 l/ha ausgebracht werden. Wasser, Öl, Netzoder Haftmittel sind bei dieser neuen Methode (Ultra-low-volume) nicht erforderlich. Wegen des außergewöhnlich geringen Spritzbrühebedarfs sind bei großflächiger Anwendung große Kosteneinsparungen zu erreichen. Es werden kurz Einzelheiten aus den in Kreta zur Bekämpfung der Olivenfliege durchgeführten Versuchen mitgeteilt. Nachdem aufgrund von neuen Versuchen das Verfahren nicht nur von Starrflügelflugzeugen, sondern auch von Hubschraubern und Bodengeräten angewendet werden kann, zeigt sich hier ein neuer Weg des gezielten Einsatzes von Pflanzenschutzmitteln, der auch im kleinparzellierten Mitteleuropa von Interesse sein dürfte. Die Auswirkungen des Verfahrens in toxikologischer und biologischer Hinsicht werden aufgezeigt und zur Diskussion gestellt.(Anm. der Schriftleitung: Das vom Verf. behandelte Verfahren wirft noch ungelöste Probleme in toxikologischer Hinsicht auf, so z. B. wie ist die Rückstandssituation in Verbindung mit der Tolerierung von Insektizid-Höchstmengen? Zurückhaltung bei der Empfehlung der Übertragung auf unsere Verhältnisse erscheint zunächst gerechtfertigt.) 相似文献
100.
Summary Cellulose nitrate fibres of three different degrees of substitution (DS) were prepared by heterogeneous reaction. The fibre surfaces were observed in the scanning electron microscope. Apart from the DS the influence of pretreatments such as prenitration and boiling of the fibres prior to nitration was studied. The results reveal an interaction between the cell wall layers and the esterification and swelling capacity of the nitration medium. In all cases the DS was determined by the composition of the nitration medium. A pretreatment influenced the fibre surfaces after nitration. The peculiar role of the primary wall during esterification is emphasized.Supported by the Federal Ministry for Research and Technology (BMFT) 相似文献