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61.
Toll‐like receptor and related cytokine mRNA expression in bovine corpora lutea during the oestrous cycle and pregnancy 下载免费PDF全文
JE Gadsby AM Tyson Nipper HA Faircloth M D'Annibale‐Tolhurst J Chang PW Farin IM Sheldon DH Poole 《Reproduction in domestic animals》2017,52(3):495-504
Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression. 相似文献
62.
KR Arrigo DH Robinson DL Worthen RB Dunbar GR DiTullio M VanWoert MP Lizotte 《Science (New York, N.Y.)》1999,283(5400):365-367
Data from recent oceanographic cruises show that phytoplankton community structure in the Ross Sea is related to mixed layer depth. Diatoms dominate in highly stratified waters, whereas Phaeocystis antarctica assemblages dominate where waters are more deeply mixed. The drawdown of both carbon dioxide (CO2) and nitrate per mole of phosphate and the rate of new production by diatoms are much lower than that measured for P. antarctica. Consequently, the capacity of the biological community to draw down atmospheric CO2 and transport it to the deep ocean could diminish dramatically if predicted increases in upper ocean stratification due to climate warming should occur. 相似文献
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An unusual outbreak of contagious ovine ecthyma 总被引:1,自引:0,他引:1
CD HAWKINS TM ELLIS MK DAVIES RL PEET J. PARKINSON 《Australian veterinary journal》1991,68(6):210-211
65.
Utilization of (3S,3'S)-astaxanthin acyl esters in pigmentation of rainbow trout (Oncorhynchus mykiss) 总被引:2,自引:0,他引:2
J. BOWEN C. SOUTAR R.D. SERWATA S. LAGOCKI D.A. WHITE S.J. DAVIES & A.J. YOUNG 《Aquaculture Nutrition》2002,8(1):59-68
The deposition of natural, optically active, astaxanthin fatty acid esters in rainbow trout ( Oncorhynchus mykiss ) was studied. Mono-esterified and di-esterified (3 S ,3' S ) astaxanthin were purified from the green microalga Haematococcus pluvialis and incorporated into extruded diets and compared with diets containing synthetic racemic astaxanthin (Carophyll Pink) and a total carotenoid extract from the alga. All sources of astaxanthin achieved >4 mg kg−1 in the white muscle after 6 weeks feeding. No significant difference ( P > 0.05) between the deposition of astaxanthin or total carotenoid for the different diets was observed. Other xanthophylls, namely lutein, zeaxanthin and idoxanthin were found in the white muscle of rainbow trout fed all diets and together accounted for 10–14% of total carotenoid. Astaxanthin was deposited in the white muscle in the stereochemical form administered in the diet, i.e. racemic astaxanthin for Carophyll Pink and ˜100% (3 S ,3' S )-astaxanthin for the algal sources. In contrast, epimerization of (3 S ,3' S ) astaxanthin from the alga was observed for the astaxanthin esters deposited in the skin of rainbow trout, with a ratio close to 1.0:2.0:1.0 (3 S ,3' S :3 R ,3' S :3 R ,3' R ). 相似文献
66.
Seed of Adonis microcarpa (pheasant's eye) fed at 5.6 g/kg of the diet induced virtually total feed refusal within 3 d in growing and finishing pigs. It also caused vomiting, rapid and shallow breathing and death in a minority. These effects were probably caused by cardiac glycosides whose structure and effects closely resemble those of digoxin. Feed intake and growth recovered within 2 weeks of removal of the seed. 相似文献
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Effects of glyphosate, paraquat, trifluralin and atrazine on activities of dehydrogenase, phosphatase and urease in one soil were measured. Only glyphosate at 21.6 kg/ha was found to inhibit the enzyme activities and generally the results were not statistically significant. Enzyme activity associated with micro-organisms proliferating in soil supplemented with lucerne meal was similarly not affected by the herbicides. Interpretation of results from enzyme activity measurements in soils treated with herbicides is discussed. It is proposed that effects of natural stress can be used to judge the relative importance of herbicide induced change. 相似文献
69.
IF Canisso LL Coffee K Ortved SL Fubini LV Monteagudo DH Schlafer RO Gilbert 《Reproduction in domestic animals》2014,49(6):e64-e69
An 8‐year‐old, mixed breed, polled goat was presented for evaluation of male‐like behaviour. Clinical findings included clitoromegaly, a heavily muscled neck, pronounced beard, and erect dorsal guard hairs, which are phenotypic characteristics commonly observed in intersex animals. Transrectal ultrasonography revealed the presence of two abdominal masses caudolateral to the uterine horns. Serum concentration of estradiol was elevated. Genetic evaluation was compatible with polled intersex syndrome defined by an XX karyotype without a Y chromosome or SRY gene. Based on gross and histologic evaluation, the abdominal masses were determined to be intra‐abdominal testes, each of which was effaced by Sertoli cell and interstitial (Leydig) cell tumours. The Sertoli cell tumours (SCTs) represented two unique histologic patterns. Regardless of pattern, neoplastic Sertoli cells were consistently lipid laden and positive for vimentin. Interstitial cell tumours (ICTs) were negative for vimentin. Clinical and histopathologic findings suggest that prolonged exposure to steroids secreted by neoplastic Sertoli cells contributed to virilization. In addition, results from immunohistochemistry indicated that vimentin may be a valuable immunodiagnostic tool for differentiation between interstitial and Sertoli cell tumours in goats. 相似文献
70.