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31.
The sites of oestrogen action can be shown by the localisation of their receptors in the target tissues. The aim of the present study was to show the localisation of oestrogen receptors in porcine embryos and fetuses obtained on days 18, 22, 32, 40, 50, 60, 71 and 90 post coitum (p.c.). The visualisation of proteins was conducted in embryos and various fetal organs such as gonads, uterus, lung, kidney, intestine and adrenal gland. Both ERs were observed in the blastocysts on day 18 p.c. In the male, ERbeta was detected in the testis and epididymis, whereas ERalpha was present in the efferent ductules. In the female, ERbeta was detected in the ovarian stromal cells investing the oocyte nests, while ERalpha protein was detected in the surface epithelium. In the uterus, ERs were present in the stromal cells, while ERbeta was present in the luminal epithelium. In the non-reproductive fetal porcine tissues ERbeta was localised in the lungs, kidneys, adrenal glands and in the umbilical cords. Both ERs were observed in the intestine. It is possible that ERbeta may play important roles in the development of the adrenal gland, testis, kidney and lungs, while both ERs are involved in the development of the ovary, uterus, epididymis and intestine of the porcine fetus.  相似文献   
32.
The aim of this study was to find the biochemical markers of blackleg, evoked by the fungus Leptosphaeria maculans in seedlings of oilseed winter rape. Analyses of antioxidant enzymes activity and reactive oxygen species detection were performed 24, 48 and 72 h after inoculation. Moreover, measurements of the total pool of phenolic compounds, trans-cinnamic acid and ferulic acid were carried out. The results proved the virulence of Ph L5 isolate towards the rape seedlings. An increase in total phenolic content, including trans-cinnamic acid, was observed 24 h after inoculation. High activity of phenylalanine ammonia-lyase is probably another symptom of the defense mechanisms, despite the fact that it was not accompanied by elevated phenolics level, which were probably rapidly exhausted during Phoma lingam inoculation. A drop in phenolics content was balanced by higher activity of SOD, CAT and non-specific peroxidases. Enhanced activity of these enzymes was a response to the reactive oxygen species overproduction. ROS accumulation in indirectly inoculated first true leaves after inoculation may suggest a systemic defense response.  相似文献   
33.
In the experiments done in 2008 and 2009, 23 selected caraway genotypes originating from European botanical gardens (18), cv. “Kończewicki” and our own breeding strains were tested. The obtained results showed that objects of the caraway collection varied in terms of all the tested morphological traits. The plant height ranged from 71.5 cm (Reykjawik) to 107.8 cm (cv. “Kończewicki”). The number of branches on the main stem was from 5.3 (Reykjawik) to 10.0 (Jena). The number of lateral shoots ranged from 9.8 (Reykjawik) to 21.5 (strain 9/10). The leaf length was from 11.9 cm (Lousanne) to 29.1 cm (cv. “Kończewicki”). The number of umbels per plant varied from 91.4 (Reykjawik) to 251.9 (strain 9/10). The fruit yield ranged from 14.2 g (Reykjawik) to 48.5 g (cv. “Kończewicki”). The weight of 1000 seeds was from 1.81 g (Salzburg) to 3.31 g (strain 9/1). The following morphological traits such as the number of umbels per plant, the number of lateral shoots per plant and weight of a thousand seeds had positive effect on fruit yield. The multidimensional analysis of the tested traits compared caraway objects in respect of eight morphological traits and yield simultaneously. These valuation of caraway genotypes will make it possible to choose the appropriate genotypes for further breeding program.  相似文献   
34.
Increased occurrence of cucumber angular leaf spot, Pseudomonas syringae pv. lachrymans, has caused significant losses in cucumber, Cucumis sativus, yield in Poland in recent years. These losses necessitated evaluation of the level of resistance in cucumber cultivars of mainly Polish breeding, cultivated in Eastern Europe, and initiation of a breeding programme for resistance to this disease. Screening for resistance was performed on 84 cucumber accessions under growth chamber conditions using a highly aggressive strain of P. syringae pv. lachrymans. Most of the screened accessions were either susceptible or displayed intermediate resistance. The screening resulted in the identification of five F1 hybrid cultivars moderately resistant to angular leaf spot. The identified F1 hybrids were self-pollinated up to the F4 generation. Individuals resistant to angular leaf spot were identified. These individuals can be used as a source of resistance to angular leaf spot in future breeding efforts.  相似文献   
35.
In the moderate climate of Poland it is recommended that milk thistle (Silybum marianum L. Gaertn.) be grown on fertile soils. The plant, however, develops a strong root system, so a working hypothesis has developed that cultivation can be extended to light soils with periodic water deficits. The aim of the present research was to determine the effects of sowing milk thistle on light soil at different dates and rates on the achene yield and flavonolignan content. This experiment was carried out during 2004-2006 at the Mochelek Experiment Station of the University of Technology and Life Sciences in Bydgoszcz (53°13′ N; 17°51′ E). The average fruit yields were 1.23 t ha−1; those of silymarin were 26.5 kg ha−1. The moisture and thermal conditions during the research years caused the fruit yields to range from 0.55 to 1.68 t ha−1 and silymarin yields from 13.3 to 35.4 kg ha−1. Delaying sowing from early to mid-April increased the plant density and decreased numbers of inflorescences and fruits per inflorescence; as a result, no effect of sowing date on fruit yield was found. Delaying the sowing date increased silymarin content by about 0.4% and its yield by 5.3 kg ha−1. Increasing the sowing rate from 12 to 24 kg ha−1 resulted in a slight (40 kg ha−1) but significant increase in achene yield; however, it did not affect the silymarin content. The average silymarin content in fruits was 2.18%. The ratio of silydianin to silychristin was 1:2.2, and the ratio of silydianin to the sum of silybinin and isosilybinin was 1:3.3.  相似文献   
36.
This study analyzed the morphological development and allometric growth patterns of Lota lota L. (burbot) larvae reared under controlled laboratory conditions. From hatching to day 50, twenty larvae were sampled each [between 1 and 14 days post-hatch (DPH)] or every second day (between 14 and 50 DPH) and measured under a stereoscopic microscope using analytic software. Based on the external morphology, the different stages during early development of burbot were identified: yolk sac larva 0–8 DPH [3.92–4.37 mm total length (TL)]; preflexion larva 9–26 DPH (4.57–12.06 mm TL); flexion larva (between notochord degradation and its replacement with rays) 28–34 DPH (14.00–16.34 mm TL) and postflexion larva/juvenile 36–50 DPH (18.20–29.27 mm TL). Allometric growth patterns of some parameters (e.g., total length, head length, body length, tail length, head depth, body depth, eye diameter) were modeled by a power function and described by the growth coefficient. Organogenesis and changes of body proportions in burbot larvae were more rapid and complex during the yolk sac and preflexion phase of development as larvae developed most of their sensorial, feeding, respiratory and swimming systems and after notochord flexion, when most morphological changes were related to the progressive transformation from pelagic larva to demersal larva/juvenile.  相似文献   
37.
The aim of this work was to analyse the response of Rosa rubiginosa to salinity induced by different concentrations of sodium chloride and calcium chloride (0, 25, 50, 100, 150 and 200 mM). Besides salt accumulation and pH changes, other parameters were investigated including photosynthetic activity, leaf water content, the dynamics of necrosis and chlorosis appearance and leaf drying. The study was complemented with microscopic analysis of changes in leaf anatomy. R. rubiginosa was more sensitive to the salinity induced by calcium chloride than by sodium chloride. Plant response to salinity differed depending of the salt concentration. These differences were manifested by higher dynamics of necrosis and chlorosis appearance and leaf drying. CaCl2 showed greater inhibition of the photosynthetic apparatus and photosynthetic activity. Treatment with CaCl2 caused more visible deformation of palisade cells, reduction in their density and overall reduction in leaf thickness. The study demonstrated higher accumulation of CaCl2 in the soil, and thus greater limitations in water availability resulting in reduced leaf water content and quicker drying of leaves as compared with NaCl-treated plants.  相似文献   
38.
39.
The aim of this work was to compare the effects of controlled reproduction of cultured and wild common barbel, Barbus barbus (L.). Preparations containing different GnRH analogues and dopamine receptor antagonists (Ovopel, Ovaprim) as well as human chorionic gonadotropin (hCG) (in the case of cultured fish) were applied and their influence on ovulation, spermiation and quality of gametes obtained was determined. No differences in the qualitative or quantitative parameters of semen were found between fish stimulated with different hormonal preparations and those not receiving hormonal stimulation. The high suitability of Ovaprim for ovulation induction in (cultured and wild) barbel was confirmed. The highest synchronisation of ovulation was obtained after the application of Ovopel (18 ± 3 h), but the best results of controlled reproduction (expressed as the percentage of ovulations and survival of embryos) were obtained by applying Ovaprim (83.2 ± 4.1). A significantly higher percentage of ovulation was obtained in cultured fish (80-90%) than in wild fish (< 25%).  相似文献   
40.
In Poland bread as a staple food both made from wheat and rye flour can be a potential product for future fortification with folic acid. The objective of the study was to examine the effect of fermentation and baking on added folic acid and some endogenous folates stability during breadmaking of rye and wheat breads. Breads were produced using the formulation containing enriched flour with 0.2 mg folic acid/100 g product, baker’s yeast and additionally ascorbic acid for wheat bread and lactic acid for rye bread. Folates were extracted with Hepes/Ches buffer (pH = 7.85) followed by destruction of matrix by amylase and protease and deconjugation with rat serum conjugase. Affinity chromatography (FBP bovine milk) was used to purify and concentrate samples. The folates were separated by HPLC with C18 column and with a combination of fluorescence and UV detection. For both rye and wheat breads there was a decrease of folic acid from flour to bread stage. The total losses depend on baking process and ranged from 12 to 21%. Some changes in the level of different native folate forms during the stage of baking process were also observed.  相似文献   
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