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There were repeated histological bioptic examinations of the endometrium during the period from the second to twentieth day post partum (p.p.) in cows with afterbirth retention (n = 5), with developing puerperal endometritis (n = 5), and with a physiological course of puerperium (n = 5). In cows with a physiological course of puerperium, a finished process of epithelization of endometrium with a morphological and functional consolidation of the epithelium could be observed on the 20th day p.p. In cows with disturbed puerperium, the surface epithelium still exhibited signs of disintegration and a low secretion activity. The endometria of both groups of cows with pathological puerperium had a high degree of infiltration with neutrophil granulocytes: in cows with retained afterbirth this picture was characteristic already the second day p.p. On the other hand, the endometrium of cows with physiological puerperium was characterized by a higher occurrence of folliculoid nodules as early as on the tenth day p.p., and a rapid increase in the number of fat cells and activated histiocytes--macrophages could be observed in the endometrium of these cows between the 15th and 20th day p.p. The dynamics of occurrence of mobile cells in the studied groups of cows confirmed their importance for a physiological course of the restitution of endometrium during the puerperium of cows. 相似文献
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D. M. Kummer 《Agroforestry Systems》1992,18(1):31-46
Population pressure, expansion of small-scale agriculture and shifting cultivation are commonly cited as the causes of tropical deforestation. A close examination of deforestation and agriculture in the Philippine uplands reveals, however, that the vast majority of agriculturists must be sedentary farmers. In addition, the importance of population pressure as a cause of deforestation in the Philippines cannot be supported by the available evidence. Lastly, the concept of arable land is shown to be of limited value in discussing upland agriculture in the Philippines. 相似文献
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Retracted: Effect of Post‐Thaw Storage Time on Motility and Fertility of Cryopreserved Beluga Sturgeon (Huso huso) Sperm
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The aim of this study was to test the influence of post ‐ thaw storage time on the duration of sperm motility, percentage of motile sperm, and fertilization and hatching rates of fresh sperm and sperm stored for 0, 30 and 60 min at 4°C post‐thawing. After being frozen in liquid nitrogen and then thawed, the percentage of motile sperm and duration of motility were not affected by 30 min of storage at 4°C, whereas a significant decline in these parameters was observed after 60 min of storage. Similarly, fertilization and hatching rates were significantly affected within 60 min of storage at 4°C, and the fertility of frozen‐thawed sperm was significantly lower than that of fresh sperm. We conclude that cryopreserved sperm of beluga sturgeon could be stored for 30 min without the loss of sperm quality. This described procedure for beluga sturgeon cryopreservation is reliable and efficient and therefore can be recommended for hatchery practice after scaling up this technique. 相似文献
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Two cases of Rhodococcus equl infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equl until proven otherwise. 相似文献
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