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排序方式: 共有169条查询结果,搜索用时 15 毫秒
1.
G Zamaratskaia J Babol A Madej EJ Squires K Lundström 《Reproduction in domestic animals》2004,39(3):168-172
This study describes the age-related variation in boar taint compounds, skatole and androstenone, and testosterone, oestradiol-17 beta (E17 beta), oestrone sulphate (ES), dehydroepiandrosterone sulphate (DHEAS), triiodothyronine (T(3)) and insulin-like growth factor-1 (IGF-1) in six boars. Three pairs of littermates of crossbred entire male pigs (from three Yorkshire x Duroc dams and one Hampshire sire) were included. Blood samples were taken at the age of 9-15 weeks and thereafter at weekly intervals from the age of 20-32 weeks. Plasma concentrations of skatole, androstenone, testosterone, E17 beta, ES, DHEAS, T(3) and IGF-1 were measured. We found that skatole levels in boars increased at the age around puberty after an increase in the levels of testicular steroids. Levels of skatole were not associated with the levels of sex steroids, T(3) and IGF-1. However, the increased level of testicular steroids is probably the underlying factor needed for high skatole levels to occur although the specific mechanism leading to increased skatole levels remains unknown. 相似文献
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Most scientific attention on port studies centers on deep sea ports, especially container ports. In this paper, in contrast, attention is focused on the spatial–temporal development of inland waterway ports on the Midstream Yangtze River from 2001 to 2013. The aim of this study is to assess two relevant and complementary questions of the hinterland evolution: its geographical extent and the coordination relationship with the inland port. To conduct the study, it was necessary to first identify the boundaries of the ports' hinterlands within the given timeframe. Then, the coupling coordination degree model was introduced to explore the underlying relationship between the port service and hinterland economy. Furthermore, to better depict the intricate economic characteristics of the hinterland, the development stage theory was applied in the models. The results highlight the emergence of a discontinuous hinterland at Wuhan Port and its reinforcement of primacy with respect to fierce hinterland rivalry. It also demonstrates that an interplay between major ports and their corresponding hinterlands evolves from the transitional stage, characterized by lagging port service, to the multi‐stage, wherein the supply of ports partly outstrips hinterland demand. 相似文献
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Lau KW Kruth SA Thorn CE Vernau W Moore P 《The Canadian veterinary journal. La revue veterinaire canadienne》1999,40(10):725-728
A mixed breed dog was diagnosed with large granular lymphocytic leukemia. Immunophenotypic analysis indicated the lymphocytes were CD3+, CD8+ T cells expressing the alpha beta T cell receptor and a leukointegrin, alpha d. Chemotherapy and splenectomy resulted in an initial reduction in the lymphocyte count. 相似文献
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Summary Effects of moisture content on bending strength and section capacity have been studied assuming that strength properties are linearly related to moisture content below the fiber saturation point. The models developed using the linear strength vs. moisture content relationships are compared with quadratic models developed earlier. The linear representation of strength variation with moisture content leads to predicted member bending capacity relationships which show that increases in member bending strength with moisture content will compensate for section property decreases at all bending strength property levels. Comparisons of bending strength and bending capacity models show that the two modelling approaches lead to similar predicted member performance. Simplified procedures are provided for adjusting member bending strength for moisture content which are suitable for materials properties codes or standards. 相似文献
6.
Immunohistochemical Expression of Growth Factors in the Follicular Wall of Normal and Cystic Ovaries of Sows
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FJF Sant'Ana JL Reis Junior GR Blume EJ Gimeno F Rey HH Ortega 《Reproduction in domestic animals》2015,50(2):327-332
The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF‐I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF‐I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF‐II was very similar to pattern noted in IGF‐I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF‐II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors. 相似文献
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Correlative biomechanical and histologic study of the cranial cruciate ligament in dogs 总被引:5,自引:0,他引:5
P B Vasseur R R Pool S P Arnoczky R E Lau 《American journal of veterinary research》1985,46(9):1842-1854
The mechanical properties of the cranial cruciate ligament were determined, using unilateral bone-ligament-bone preparations from 65 dogs of various ages and body sizes. Tensile loading of the cranial cruciate ligament from 1 of each pair of stifle joints demonstrated a decrease in material properties (modulus, maximum stress, strain energy) with aging. The decreases in maximum stress and strain energy with age were significantly less (P less than 0.05 and P less than 0.05, respectively) in the cranial cruciate ligament from dogs weighing less than 15 kg, compared with those weighing 15 kg or more. The cranial cruciate ligament and remaining femorotibial ligaments were collected from the opposite stifle joints and examined microscopically. By 5 years of age, the cranial cruciate ligaments of dogs weighing greater than 15 kg consistently had microscopic evidence of degenerative disease (loss of ligamentocytes, metaplasia of surviving ligamentocytes to chondrocytes, and failure to maintain collagen fibers and primary collagen bundles) which progressed in severity with age. The caudal cruciate ligaments were similarly affected, although the degenerative changes were rarely as severe as in the cranial cruciate ligament. The collateral ligaments underwent minimal degeneration. Sex differences had no bearing on degeneration. The cranial cruciate ligaments in dogs weighing less than 15 kg generally had less severe alterations than those in heavier dogs, and the onset of the degenerative process was delayed by several years. Cranial cruciate ligaments removed from dogs after ligament failure not only had degenerative disease, but also had undergone unsuccessful attempts at repair. In contrast, fibrous repair was rarely present in intact ligaments of asymptomatic dogs with degenerative disease of the cranial cruciate ligament. 相似文献
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Intention is central to the concept of voluntary action. Using functional magnetic resonance imaging, we compared conditions in which participants made self-paced actions and attended either to their intention to move or to the actual movement. When they attended to their intention rather than their movement, there was an enhancement of activity in the pre-supplementary motor area (pre-SMA). We also found activations in the right dorsal prefrontal cortex and left intraparietal cortex. Prefrontal activity, but not parietal activity, was more strongly coupled with activity in the pre-SMA. We conclude that activity in the pre-SMA reflects the representation of intention. 相似文献