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41.
Interleukin-1β (IL-1β) may regulate ovarian physiology. In this study, the influence of IL-1β on secretory activity within the corpora lutea (CL) of cyclic and gravid pigs was determined in vitro during different stages of the CL lifespan, e.g. on Days 10-11, 12-13 and 15-16 of the oestrous cycle and pregnancy. IL-1β (10 ng/ml) increased prostaglandin E2 (PGE2) secretion from CL of the cyclic and gravid pigs during studied days of the oestrous cycle and pregnancy. Increase (P < 0.05) of prostaglandin F2α (PGF2α) in IL-1β-treated CL was demonstrated only on Days 10-11 of the oestrous cycle. More potent stimulatory effect of IL-1β on PGE2 than PGF2α secretion resulted in the enhancement of the PGE2:PGF2α ratio in cyclic and early pregnant CL. IL-1β increased (P < 0.05) progesterone (P4) secretion only in gravid CL and had no effect on oestradiol-17β (E2) release. Expression of cyclooxygenase-2 (COX-2) mRNA was stimulated (P < 0.05) in IL-1β-treated cyclic and gravid CL. Expression of prostaglandin synthase mRNAs in response to IL-1β did not increase. In conclusion, IL-1β modulates PGE2, PGF2α and P4 secretion from porcine CL, depending on luteal stage and the surrounding hormonal milieu. The cytokine may act locally in porcine CL for luteotrophic support throughout the PGE2-mediated synthesis and secretion. 相似文献
42.
Maki Ishiki Hideaki Sakihama Seizen Agata Akira Tokuyama 《Water, air, and soil pollution》2009,198(1-4):111-124
The chemical characteristics of the Urauchi River water in Iriomote Island National park, Okinawa, Japan have been studied. Concentrations of PO4 3?, NO2 ?, and NH4 + were barely detectable. We compared the concentration ratios of Mg2+/Na+, HCO3 ?/Na+, and Ca2+/Na+ in the Urauchi River to those of 60 large rivers in the world and indicated that the chemical composition of the river is most likely formed by the binary mixing of sea salt components and silicate rock weathering components. Although rock weathering in the catchments area is driven by both H2CO3 and H2SO4, the role of H2CO3 is dominant. The percentages of the concentration of each cation in the river water are almost the same as those of other rivers with drainage areas consisting of silicate rock and sandstone. Thus, the Urauchi River shows the typical chemical characteristics of a river in a silicate rock area that includes sandstone. 相似文献
43.
Simone DI PRIMA Jess RODRIGO-COMINO Agata NOVARA Massimo IOVINO Mario PIRASTRU Saskia KEESSTRA Artemi CERD 《土壤圈》2018,28(3):463-477
Soil capacity to support life and to produce economic goods and services is strongly linked to the maintenance of good soil physical quality (SPQ). In this study, the SPQ of citrus orchards was assessed under three different soil managements, namely no-tillage using herbicides, tillage under chemical farming, and no-tillage under organic farming. Commonly used indicators, such as soil bulk density, organic carbon content, and structural stability index, were considered in conjunction with capacitive indicators estimated by the Beerkan estimation of soil transfer parameter (BEST) method. The measurements taken at the L'Alcoleja Experimental Station in Spain yielded optimal values for soil bulk density and organic carbon content in 100% and 70% of cases for organic farming. The values of structural stability index indicated that the soil was stable in 90% of cases. Differences between the soil management practices were particularly clear in terms of plant-available water capacity and saturated hydraulic conductivity. Under organic farming, the soil had the greatest ability to store and provide water to plant roots, and to quickly drain excess water and facilitate root proliferation. Management practices adopted under organic farming (such as vegetation cover between the trees, chipping after pruning, and spreading the chips on the soil surface) improved the SPQ. Conversely, the conventional management strategies unequivocally led to soil degradation owing to the loss of organic matter, soil compaction, and reduced structural stability. The results in this study show that organic farming has a clear positive impact on the SPQ, suggesting that tillage and herbicide treatments should be avoided. 相似文献
44.
The reproduction rate of horses is one of the lowest within domestic livestock despite advances the veterinary medicine. Infertility in horses may be due mainly to the lack of suitable selection criteria in the breeding of horses. However, acquired infertility due to genital, bacterial infections may occur. Mycoplasmas have been implicated in genital disorders and infertility of many species including humans and horses. However, their role as commensals or pathogens of the genital tract of horses is still not determined. Bacteriological examinations made on the fossa glandis, urethra, penis and semen of stallions, showed the presence of different Mycoplasma species. Therefore our study aimed to find the prevalence of Mycoplasma species and a possible association with fertility problems in Danish riding horses. Eighty semen samples from stallions and 19 vaginal swab samples from mares were tested by PCR for presence of mycoplasmal DNA. The vaginal swab samples were also cultured in the Mycoplasma specific medium. None of the samples were positive for presence of genital mycoplasmas during the screen. The lack of genital mycoplasmas observed in this study may be due to a very extensive use of artificial insemination of modern sport horses. 相似文献
45.
46.
Agata Jędrzejuk Lara Meyer Margrethe Serek 《The Journal of Horticultural Science and Biotechnology》2017,92(5):493-501
Petunia and Calibrachoa are ornamental plants of worldwide economic importance. Commercially, it is useful to combine desirable characteristics of Calibrachoa, including the large diversity of flower colors, with the pH tolerance and vigorous growth of Petunia. For investigation of interspecific hybrids between Petunia and Calibrachoa we used four different introns with flanking exon areas, each from a different gene and with a different sequence for Petunia and Calibrachoa, as genus-specific markers for chromosomes in interspecific hybrids. PCR primers specific for Petunia and Calabrachoa were made from the determined sequences and tested on a range of presumed hybrids using multiplex PCR, which confirmed that the hybrids were derived from these two species. Flow cytometry demonstrated that the hybrids were triploid, and determination of chromosome numbers showed that two of the chromosome sets were from Calibrachoa, i.e. that the other parent, Petunia, was diploid. Similar methods can be used for molecular characterization of other new hybrids made between closely related species or cultivars. 相似文献
47.
Broodstock of mature Japanese medaka (Oryzias latipes Temminck and Schlegel, 1846) (mean weight 0.45 ± 0.03 g; age 6 months) were maintained in glass aquaria (8 males and 8 females in each aquarium). The fish were fed commercial feed (group C) or this feed was supplemented with arachidonic acid ARA (2 % of total fatty acids in feed; group A) and one of the COX inhibitors: resveratrol (group AR) or NS-398 (group ANS) with amount 20 mg kg?1 BW day?1 of one of the COX inhibitors. The effect of 2 weeks of feeding experimental diets on reproductive parameters (fecundity, embryo and larval survival, hatching rate, and larvae body weight) was analyzed. Larvae (obtained from experimental dietary treatments) were reared for 2 weeks. The percent of spawning female and fecundity was similar in dietary treatments. COX inhibitors in broodstock diet caused a decrease in embryo survival rate. Eggs of medaka from group ANS and AR revealed the lowest hatchability rate. In contrast, group A revealed a higher hatchability rate at the same time. Larval body weight after hatching was significantly the highest in this group. At the end of the experiment, larvae body weight ranged from 1.62 ± 0.43 mg in group AN to 2.89 ± 0.74 mg in group A. These results show that the COX inhibitors decreased gamete and larval quality regardless of high levels of ARA in broodstock diet. 相似文献
48.
Rasmussen M Guo X Wang Y Lohmueller KE Rasmussen S Albrechtsen A Skotte L Lindgreen S Metspalu M Jombart T Kivisild T Zhai W Eriksson A Manica A Orlando L De La Vega FM Tridico S Metspalu E Nielsen K Ávila-Arcos MC Moreno-Mayar JV Muller C Dortch J Gilbert MT Lund O Wesolowska A Karmin M Weinert LA Wang B Li J Tai S Xiao F Hanihara T van Driem G Jha AR Ricaut FX de Knijff P Migliano AB Gallego Romero I Kristiansen K Lambert DM Brunak S Forster P Brinkmann B Nehlich O Bunce M Richards M Gupta R 《Science (New York, N.Y.)》2011,334(6052):94-98
We present an Aboriginal Australian genomic sequence obtained from a 100-year-old lock of hair donated by an Aboriginal man from southern Western Australia in the early 20th century. We detect no evidence of European admixture and estimate contamination levels to be below 0.5%. We show that Aboriginal Australians are descendants of an early human dispersal into eastern Asia, possibly 62,000 to 75,000 years ago. This dispersal is separate from the one that gave rise to modern Asians 25,000 to 38,000 years ago. We also find evidence of gene flow between populations of the two dispersal waves prior to the divergence of Native Americans from modern Asian ancestors. Our findings support the hypothesis that present-day Aboriginal Australians descend from the earliest humans to occupy Australia, likely representing one of the oldest continuous populations outside Africa. 相似文献
49.
Luciana Migliore Alice Rotini Davide Randazzo Nadia N Albanese Agata Giallongo 《BMC ecology》2007,7(1):6
Background
The endemic seagrass Posidonia oceanica (L.) Delile colonizes soft bottoms producing highly productive meadows that play a crucial role in coastal ecosystems dynamics. Human activities and natural events are responsible for a widespread meadows regression; to date the identification of "diagnostic" tools to monitor conservation status is a critical issue. In this study the feasibility of a novel tool to evaluate ecological impacts on Posidonia meadows has been tested. Quantification of a putative stress indicator, i.e. phenols content, has been coupled to 2-D electrophoretic protein analysis of rhizome samples. 相似文献50.