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161.
The objective of the study was to demonstrate the presence of estrogen receptor alpha (ERalpha) and beta (ERbeta) protein and corresponding mRNA in porcine ovarian follicles and corpora lutea obtained on day 10, 18, 32, 50, 71 and 90 post coitum (p.c.) using immunohistochemistry, Western blot, and RT-PCR analysis. Immunohistochemistry showed that ERalpha protein was located in the granulosa cells of ovarian follicles and the strongest immunoreaction was observed on days 32 and 50 p.c. The ERbeta protein was found mainly in theca cells of follicles as well as in luteal cells. The most intense immunoreaction was observed on day 18 p.c. within theca cells, while in the corpus luteum (CL) the intensity of ERbeta staining gradually increased and remained elevated at mid and late pregnancy. In CL by day 50 p.c. immunoreaction for ERbeta was present only in small luteal cells, but starting from day 71 to 90 p.c. it was observed in both small and large luteal cells. Western blot analysis was performed and validated data obtained from immunohistochemistry. RT-PCR results indicated that ERalpha mRNA was expressed only in ovarian follicles of the pregnant swine, while that of ERbeta in both follicles and CL. The results suggest an autocrine/paracrine role of estrogens acting via both ERalpha and ERbeta in the regulation of the ovarian function during pregnancy and for the process of successful reproduction.  相似文献   
162.
We tested the hypothesis that leaf age affects photosynthetic induction, because conductance to CO2 diffusion usually decreases with increasing leaf age. Photosynthetic inductions, primarily determined by the light modulation of Rubisco activity and stomatal opening, were investigated in both young and mature leaves, as defined by leaf plastochron index (LPI), from three poplar clones: Populus alba L., P. nigra L. and P. x euramericana (Dode) Guinier. In all clones, maximum assimilation rates (A max), maximum stomatal conductance (G Smax) and dark respiration rates (RD) were higher in young leaves (LPI = 3-5) than in mature leaves (LPI = 10-14), and A max decreased from P. alba via P. x euramericana to P. nigra. The clones with high photosynthetic capacity had low induction states 60 s after leaf illumination (IS60; indicating a slow initial induction phase), and required less time to reach 90% photosynthetic induction (T90). In contrast, the clone with the lowest photosynthetic capacity (P. nigra) exhibited high IS60 (high initial induction state) but a long induction time (high T90). A comparison of mature leaves with young leaves revealed significantly (P < 0.01) lower IS60 values in mature leaves of P. nigra only, and significantly higher T90 values in mature leaves of P. alba only. In all clones, young leaves exhibited a lower percentage of maximum transient stomatal limitation during photosynthetic induction (4-9%) compared with mature leaves (16-30%). Transient biochemical limitation, assessed on the basis of the time constants of Rubisco activation (tau), was significantly higher in mature leaves than in young leaves of P. alba; whereas there were no significant differences in tau between young and mature leaves of the other poplar clones. Thus, our hypothesis that leaf age affects photosynthetic induction was confirmed at the level of transient stomatal limitation, which was significantly higher in mature leaves than in young leaves in all clones. For the induction parameters IS60, T90 and tau, photosynthetic induction was more clone-specific and was dependent on leaf age only in some cases, an observation that may apply to other tree species.  相似文献   
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There is a need for simple, fast, efficient and sensitive methods of analysis for glyphosate and its degradate aminomethylphosphonic acid (AMPA) in diverse matrices such as water, plant materials and soil to facilitate environmental research needed to address the continuing concerns related to increasing glyphosate use. A variety of water‐based solutions have been used to extract the chemicals from different matrices. Many methods require extensive sample preparation, including derivatization and clean‐up, prior to analysis by a variety of detection techniques. This review summarizes methods used during the past 15 years for analysis of glyphosate and AMPA in water, plant materials and soil. The simplest methods use aqueous extraction of glyphosate and AMPA from plant materials and soil, no derivatization, solid‐phase extraction (SPE) columns for clean‐up, guard columns for separation and confirmation of the analytes by mass spectrometry and quantitation using isotope‐labeled internal standards. They have levels of detection (LODs) below the regulatory limits in North America. These methods are discussed in more detail in the review. © 2015 Society of Chemical Industry  相似文献   
166.
Journal of Soils and Sediments - The aim of the study was to compare the activity, functional diversity, and community-level physiological profiles of soil microorganisms in light of soil physical...  相似文献   
167.
A three-year test of growth performance andoffspring survival from top-crossing of commoncarp hybrids in low altitude (350 m above thesea level, middle European climate) and in highaltitude (750 m above the sea level, middleEuropean climate) was terminated by assessmentof slaughtering value of edible parts in therespective strains. A recently establishedHungarian synthetic mirror carp strain (HSM)was chosen for testing as maternal strain. TheHSM, as well as wild Amur carp (AC), Ropshacarp (ROP) and Tata carp (TAT) were used aspaternal strains.The evidential strain*altitude interactioneffect was demonstrated as significant forweight of fish (0.0005), fillet without skin(0.0001), index of highbackedness (0.005),index of head length (0.0404),Fulton's coefficient (0.0497),index of widebackedness (0.0315) andgonadosomatic index (0.0082). The interactioneffect was demonstrated as insignificantbetween altitude*sex and betweenstrain*sex.The comparative test of analysis of variance(ANOVA) revealed significantly (P < 0.05)higher weight of fish after killing on lowaltitude (1611.6 g) than on high altitude(1090.3 g), but processed body yield andpercentage of fillet without skin was notsignificantly different (64.0 and 34.2 for lowaltitude, 64.2 and 33.4 for high altitude). Thepercentage of processed body weight andpercentage of fillet without skin in analysisboth altitudes were significantly better infemales (65.5 and 34.6%) than in males (62.5and 33.00%), respectively. The highestsignificant differences in weight of fish afterkilling were found between HSM (890.8 g) andHSM × AC (1283.3 g) in high altitude. In lowaltitude, it was between HSM (1527.2 g) andHSM × AC (1706.9 g) and HSM × ROP (1693.0 g).  相似文献   
168.
Cuphea is a potential new oilseed crop rich in medium-chain fatty acids (C8:0 to C14:0) that may serve as a renewable, biodegradable source of oil for lubricants, motor oil, and aircraft fuel. Impacts of climate and soil environment on cuphea growth and development are not well understood. The objective of this study was to evaluate the influence of climate and soil on growth, seed yield, and seed oil characteristics of two semi-domesticated cuphea genotypes [PSR23 and HC-10 (Cuphea viscosissima Jacq. × C. lanceolata W.T. Aiton)] and three wild species [Cuphea wrightii, Cuphea lutea, and C. viscosissima (VS-6-CPR-1)] that show potential for domestication. The study was conducted in 2007 and 2008 at field sites in North Dakota (ND), Minnesota (MN), Iowa (IA), and Illinois (IL). Cuphea PSR23 and HC-10 were direct seeded in the field, while the three wild species were transplanted. The two plantings were treated as separate experiments. Plant growth, seed yield and oil content for the two direct-seeded lines tended to be distinctly greater in MN and ND than IL and IA, which was related more to growth temperature than soil environment. The three wild species generally performed similarly across the four different environments. C. wrightii had the greatest oil content, ranging from 320 to 360 g kg−1, which was comprised of 59-64% lauric acid. For each genotype, the content of its most prominent saturated medium-chain fatty acid (e.g., C10:0 or C12:0) increased with decreasing latitude of field site. Seed yields for C. wrightii and C. lutea were as high as 1116 kg ha−1. Combined with relatively high seed oil contents (280-350 g kg−1) these species may be good candidates for domestication. Results indicate that PSR23 and HC-10 are more regionally adapted than the wild species studied, which tended to exhibit a greater range of adaptability to climate and soil conditions.  相似文献   
169.
A common global trend in modern aquaculture is to reduce or replace fishmeal in fish diets with alternative protein sources, mainly from protein‐rich plants such as soybean; however, plant‐based aquafeeds are a source of substantial amounts of phytoestrogens. Phytoestrogens belong to endocrine‐disrupting chemicals (EDCs) which can negatively interfere with fish reproduction; thus, they should be avoided in sturgeon diet. Therefore, the aim of the study was to evaluate concentrations and the profile of dietary isoflavone phytoestrogens in the two commercial sturgeon diets. A substantial amount of isoflavones, reaching in total from 1.5 to 50 mg/kg of feed, were found in analysed diets. Genistein and daidzein, which are typical constituents of soybean, were the most abundant phytoestrogens in the analysed feeds. Equol, the third most abundant phytoestrogen in the tested samples, was originated most probably from animal components. Additionally, the accumulation of dietary isoflavones in the liver, blood and gonads of two commonly farmed sturgeon species (Acipenser gueldenstaedtii and Acipenser baerii) after long‐term dietary exposure was also assessed. Significant concentrations of isoflavones were found in liver and blood samples of both sturgeon species at 600th and 800th dph, indicating high accumulation of these compounds, which may lead to endocrine disturbance.  相似文献   
170.
In general, the effects of dietary fatty acids (FA) on sperm quality have received less attention than egg quality, and were never studied in perch. This study investigated the effects of dietary FAs on the quality and chemical composition of sperm in Eurasian perch (Perca fluviatilis). Two experimental diets containing 16% lipids and 45% proteins were compared. The n‐3/n‐6 ratios tested were 0.2 for diet 1 (D1) and 7.0 for diet 2 (D2). No significant effects of the n‐3/n‐6 ratio were observed on the sperm characteristics, either in terms of the sperm volume (around 1.2 mL) and density, spermatozoa motility (94%) and velocity, or the sperm osmolality. All these parameters corresponded to semen of good quality in Eurasian perch. Interestingly, both the FA composition and the lipid class profile of the semen were correlated to the tested diet. However, basal levels of certain highly unsaturated FAs such as eicosapentaenoic acid, 20:5 n‐3 and docosahexaenoic acid, 22:6 n‐3, were maintained in the sperm irrespective of the diet tested. Perch semen was characterized by high levels of cholesterol, phosphatidylethanolamine and phosphatidylcholine. In conclusion, the dietary n‐3/n‐6 ratio affects the lipid composition of perch semen but not the indicators of sperm quality.  相似文献   
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