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991.
A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy. 相似文献
992.
Fasciolosis is an endemic zoonotic parasitic disease with significant impacts on human health and both animal health and production. Early post-infection impacts on the host remain unclear. The objective of this study was to determine the changes, if any, to levels of endotoxin in cattle plasma in response to early-stage infection with Fasciola hepatica. Thirty-six (36) commercial bred cattle were experimentally infected with approximately 400 viable metacercariae. Plasma lipopolysaccharide (endotoxin) levels were examined on 24 occasions from 0 h before infection to 336 h after infection using the Limulus Amoebocyte Lysate chromogenic end point assay and compared with that of six (6) uninfected control animals. Peak lipopolysaccharide levels in infected animals were reached at 52 h after infection and returned to pre-infection levels at time 144 h after infection. Infected animals had significantly elevated lipopolysaccharide levels between 24 and 120 h after infection when compared to uninfected animals. The mean change in endotoxin units (EU)/mL over time after infection was statistically significant in infected animals. Elevations of lipopolysaccharide occurred in all infected animals suggesting a possible repeatable and titratable endotoxemia conducive to therapeutic agent model development. 相似文献
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996.
Lina Maria Correa E Ricardo D. Moreno José Luis Riveros 《Anatomia, histologia, embryologia》2023,52(2):336-340
This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries. 相似文献
997.
Summary Traffic during alfalfa harvest operations can cause soil compaction and damage to newly growing stems. Root exploration for soil water and nutrients, forage growth dynamics, and final yield can all be affected. The objectives of this study were to determine the long-term effects of harvest traffic and soil compaction on water-use efficiency (WUE) of alfalfa grown in a Wasco sandy loam (coarse-loamy, mixed, nonacid, thermic Typic Torriorthents). Alfalfa was planted into tilled soil and managed with or without harvest traffic. Plants subjected to traffic during harvest had a significantly lower WUE two out of the three years studied compared to plants that were never subject to traffic. The second experiment examined whether planting alfalfa into compacted soil and managed with or without harvest traffic altered WUE. Soil compaction had no affect on alfalfa WUE. It was significantly lower when grown in compacted soil and subjected to harvest traffic. It is suggested that the decrease in WUE caused by harvest traffic may be explained by plants allocating carbohydrates to damaged shoots and crowns instead of to above ground forage production. The area of the field affected by harvest traffic, which damages newly growing stems, should be minimized to increase crop water use efficiency. 相似文献
998.
Laurence E. D. Smith 《Irrigation and Drainage Systems》1990,4(4):329-343
This paper accepts that assessing the performance of irrigated agriculture is difficult because being multi-dimensional it requires a multi-disciplinary approach. Public irrigation schemes may have a number of often competing objectives and are assessed by interest groups with differing values and perspectives. A wide range of performance indicators are thus required. Some of these and the complex inter-relationships that may exist in the system are illustrated. 相似文献
999.
The organization of two farmer-managed irrigation systems in the western hills of Nepal is described by examining the ways in which the activities of water allocation, water distribution, maintenance, and resource mobilization are performed. Due to the topography and environment, these two organizations are structured primarily to mobilize the large amount of labor required for maintenance of the intake and canal. Both organizations precisely define each member's water allocation. In one system, water is allocated in proportion to the area of an individual's land holding, while in the other water allocation is by purchased shares. These two cases were used to analyze the importance of the principle of water allocation for expansion of area irrigated and equity of access to irrigation. Evidence from the two systems shows that in this hill environment water allocation by purchased shares provides the individual incentive and an organizational mechanism for efficient development of irrigation resources. Expansion of area irrigated and equity of access to irrigation were found to be greater in the system which allocates water by purchased shares than where water was allocated in proportion to area irrigated. 相似文献
1000.
Measuring yield-reducing plant water potential depressions in wheat by infrared thermometry 总被引:1,自引:0,他引:1
Summary Measurements of foliage and air wet- and dry-bulb temperatures were made over six differentially irrigated plots of Produra wheat grown at Phoenix, Arizona, in the spring of 1976. These data were used to evaluate a newly developed plant water stress index each day from the initiation of heading to the commencement of senescence. Daily measurements on total plant water potential were also obtained over this period; and after demonstrating how the atmospheric-induced component can be removed from these data, the resultant soil-induced component was plotted as a function of the new water stress index. The result was a simple linear relationship, which was found to be identical to one previously derived for alfalfa. Finally, it was shown that grain yield was directly related to the mean plant water stress index over the reproductive growth period from heading to senescence.Contribution from Agricultural Research, Science and Education Administration, US Department of AgricultureResearch physicist, soil scientist, research physicist, and research entomologist, respectively 相似文献