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排序方式: 共有88条查询结果,搜索用时 15 毫秒
31.
AP Herman T Misztal A Herman Dorota Tomaszewska – Zaremba 《Reproduction in domestic animals》2010,45(6):e426-e433
This study was designed to determine the effect of intravenous lipopolysaccharide (LPS) administration on the secretion of interleukin (IL)‐1β and IL‐1 receptors (IL‐1Rs) gene expression in the hypothalamus of anoestrous ewes. Gene expression of IL‐1β and its receptors was assayed by the real‐time polymerase chain reaction. The expression of IL‐1β in the hypothalamus was detected using Western blot. Our results showed that IL‐1β mRNA is transcribed in the ovine hypothalamus. Lipopolysaccharide increased (p ≤ 0.01) the IL‐1β gene expression in the pre‐optic area 2.4‐fold, the anterior hypothalamus (AHA) 3.4‐fold, the medial basal hypothalamus 3.7‐fold and the medial eminence 3.9‐fold. The pro‐form and mature form of IL‐1β protein were found in the hypothalamus after endotoxin injection. In general, the endotoxin also increased more than two times (p ≤ 0.01) the expression of IL‐1 receptor type I (IL‐1R1) and type II (IL‐1R2) genes in the hypothalamus, except the AHA, where the number of IL‐1R2 mRNA was extremely low and not sufficient to the quantitative analysis. These results demonstrate that the peripheral immune/inflammatory challenge increases the IL‐1β expression in the hypothalamus. This endogenous IL‐1β seems to be involved in the modulation of processes which are regulated at the hypothalamic level. One of these processes could be a reproduction. 相似文献
32.
Rzewuska M Stefańska I Osińska B Kizerwetter-Świda M Chrobak D Kaba J Bielecki W 《Veterinary microbiology》2012,159(1-2):69-76
In a breeding and fattening pig farm an increasing number of cases of abortion and generalized mycobacteriosis at slaughter occurred. Pathological findings compatible with mycobacteriosis, acid-fast organisms in tissues, and isolation of mycobacteria from tissue samples including fetuses, lungs and reproductive organs from sows, genital swabs, mesenteric lymph nodes, and from a sperm sample revealed the cause of the disease. Bacterial cultures were identified as Mycobacterium avium subsp. hominissuis using IS901-/IS1245-specific PCR. Genotyping of selected isolates from animals as well as from their environment by MIRU-VNTR analysis showed that the herd was infected with one single outbreak strain. The same genotype was also isolated from pigs of two other farms which showed comparable symptoms and were in direct contact with the index farm as well as from their environment. Immunological host responses detected by tuberculin skin test and ELISA gave positive results at herd level only. Despite the detection of other potential pathogens mycobacteria were regarded as the causative agent of the reproductive disorders. To our knowledge this is the first report of an epidemic mycobacterial infection in a pig holding associated with reproductive disorders, which could be attributed to one single virulent strain, and the first report of detection of M. avium subsp. hominissuis in pig sperm. 相似文献
33.
Changes in the quality of meat (Longissimus thoracis et lumborum) from Kamieniec lambs during long‐term freezer storage 下载免费PDF全文
Tomasz Daszkiewicz Cezary Purwin Dorota Kubiak Maja Fijałkowska Emilia Kozłowska Zofia Antoszkiewicz 《Animal Science Journal》2018,89(9):1323-1330
The aim of this study was to determine changes in the quality of lamb meat (Longissimus thoracis et lumborum), which was vacuum‐packaged and freezer‐stored (?26°C) for 6 and 12 months. The experiment was performed on 12 male lambs of the Kamieniec Longwool breed, raised to 106 days of age. In comparison with fresh meat, thawed meat was characterized by lower ash content, higher pH, greater natural drip loss and cooking loss, and lower scores for taste intensity. Vacuum packaging and low‐temperature storage protected lamb meat against oxidative changes, and alleviated the adverse effects of oxidation on the color, aroma and taste of meat. It can be concluded that freezer storage (?26°C) of vacuum‐packaged meat can help meet consumer demand for lamb meat products in periods when fresh meat is unavailable. However, it should be noted that long‐term frozen storage induces undesirable changes in meat quality, including a decrease in water‐holding capacity and taste intensity. 相似文献
34.
Lysophosphatidic acid expression in theca cells depends on the type of bovine ovarian follicle 下载免费PDF全文
E Sinderewicz K Grycmacher D Boruszewska I Kowalczyk‐Zięba I Woclawek‐Potocka 《Reproduction in domestic animals》2017,52(1):28-34
Lysophosphatidic acid (LPA) exerts various actions on the mammalian reproductive system. In cows, LPA stimulates the synthesis and secretion of luteotropic factors in the ovary, which affects the growth and development of ovarian follicles. The role of LPA in granulosa cells, oocyte and oocyte‐cumulus complex (COC) has previously been investigated; but its role in the theca layer, which is an important structural and functional component of the ovarian follicle, is still unclear. The goal of this study was to investigate the expression of LPA in theca cells originating from different bovine ovarian follicle types. Theca cells were separated from healthy, transitional and atretic ovarian follicles, based on intrafollicular estradiol: progesterone ratios. LPA concentration in the follicular fluid (FF) in different follicle types was measured, and expression of the enzymes responsible for LPA synthesis (autotaxin [AX], phospholipase A2 [PLA2]) and receptors for LPA (LPAR1‐4) were determined. The obtained results confirmed the follicle‐type dependent presence of LPA in the FF of the bovine ovarian follicles. The highest concentration of LPA was detected in follicles classified as healthy and dominant. LPAR1‐4, PLA2 and AX expression in theca cells in all of the types of follicles examined were detected at mRNA and protein level. These results suggest that theca cells can be a source of LPA synthesis other than granulosa cells and COCs, as well as the target for its action in the bovine ovarian follicle, with PLA2 and LPAR4 playing major roles in LPA synthesis and action. 相似文献
35.
In this study, the results of investigations of organic matter decomposition in natural and dredged areas of the inner Puck Bay (Baltic Sea) are presented. The dredging of relatively deep pits causes environmental problems. Researched post-dredging pits are sediment traps in which 3 times more organic carbon (Corg), 3.5 times more total nitrogen (Ntot), about 1.5 times more organic phosphorus (Porg) and 1.7 times more total phosphorus (Ptot) accumulate as compared to the non-dredged regions; they are also characterized by very intensive decomposition of organic matter. About 42, 44, 95 and 50% of the annual load of, respectively, Corg, Ntot, Porg and Ptot undergo decomposition in the dredged area, whereas the respective values for natural seabed are ca. 11, 44, 41 and 21%. Reduction of nitrogen in the pit occurs mainly through ammonification, while in the natural areas of seabed denitrification prevails. In non-dredged sediments, 84% of the released nitrogen comes from denitrification whereas in the pit, it is only 18%. Organic matter degradation in the pit sediments manifests itself by a 7-fold increase in the phosphate flux into near-bottom water as compared to natural seabed. The observed phosphate flux originated from the organic matter as well as from the decomposition of inorganic phosphorus compounds. Periodically, sulphate reduction in the pit sediments resulted in hydrogen sulfide occurrence. 相似文献
36.
AbstractThe pine tree lappet moth Dendrolimus pini (Lasiocampidae) is one of the most dangerous pests of pine Pinus sylvestris stands in Central Europe. To develop biological control method of this pest, the bioassay was made to assess the sensitivity of D. pini caterpillars to native EPMs strains representing two species: Steinernema feltiae and Heterorhabditis megidis in laboratory conditions. The results showed higher activity of S. feltiae strains which parasitized 86.7 - 100% of D. pini caterpillars, compared to the 20-100% of insects parasitized by H. megidis strain. Most nematodes were found in caterpillars treated with S. feltiae (in average 40 IJs/caterpillar), the least – in individuals parasitized by H. megidis (in average IJs/caterpillar). No effect of dose and temperature on parasitizm was found with S. feltiae strains while in H. megidis increased doses resulted in higher extensity of parasitism. The results indicate higher biological activity of S. feltiae strains and advisability of their further studies in field experiments. 相似文献
37.
Michalska A Ceglinska A Amarowicz R Piskula MK Szawara-Nowak D Zielinski H 《Journal of agricultural and food chemistry》2007,55(3):734-740
The purpose of this research was to find out the effect of flour extraction rate on the antioxidative properties of traditional rye bread and then to compare the bioactive compounds content and antioxidant properties of rye breads with commercial wheat roll. Four types of rye flour with different extraction rates of 100 (whole meal dark flour), 95 (brown flour), 90 (brown flour), and 70% (light flour) originated from Warko rye cultivar were used for traditional bread baking with sourdough fermentation. Four types of the respective rye breads were analyzed for their potentially beneficial components, including tocopherols and tocotrienols, total phenolics and flavonoids, reduced glutathione, and inositol hexaphosphates. Moreover, the phenolic acids profile was provided. The Trolox equivalent antioxidant capacity (TEAC) of the breads was evaluated using free radical scavenging activities of 80% methanol extracts against ABTS*+ radical cation (ABTS radical cation decolorization method) whereas radical scavenging activity (RSA) was determined against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*). The superoxide dismutase-like activity (SOD-like activity) was evaluated as free radical scavenging activities of PBS extracts against superoxide anion radicals (O2*-). The results were compared to whole meal rye bread as well as to wheat roll taken as representative example of wheat based bakery product. The studies showed that flour extraction rates strongly affected the content of bioactive compounds and antioxidative properties of traditionally baked rye breads. The incorporation of the rye flours with extraction rates from 100 down to 70% in the formulation caused decrease in tocopherol (T), tocotrienol (T3), inositol hexaphosphate (IP6), and phenolic compound (TPC) contents in rye breads. No changes in reduced glutathione (GSH) contents were noted between each type of rye bread. A significant decrease in Trolox equivalent antioxidant capacity and radical DDPH scavenging activity was also found in bread formulated on flour with an extraction rate of 70% in comparison to the breads formulated on flour with extraction rates from 100 to 90%. The highest SOD-like activity was noted for rye bread formulated on flour with an extraction rate of 70%. The four types of rye breads showed better antioxidative properties and higher antioxidant contents when compared to wheat roll with one exception made to tocopherols and tocotrienols. 相似文献
38.
Dorota Soltys-Kalina Jaros?aw Plich Danuta Strzelczyk-?yta Jadwiga ?liwka Waldemar Marczewski 《Breeding Science》2016,66(2):328-331
Drought tolerance in plants is a complex trait involving morphological, physiological, and biochemical mechanisms. Hundreds of genes underlie the response of plants to the stress. For crops, selecting cultivars that can produce economically significant yields under drought is a priority. Potato (Solanum tuberosum L.) is considered as drought sensitive crop, although cultivar-dependent differences in tolerance have been described. Cultivar ‘Katahdin’ possesses many appropriate characteristics and is widely used for breeding purposes worldwide; it also has enhanced tolerance to drought stress. In this study, we evaluated cv. ‘Katahdin’ and a half-sib family of 17 Katahdin-derived cultivars for leaf relative water content (RWC) and tuber yield under drought stress. The yields of cultivars ‘Wauseon’, ‘Katahdin’, ‘Magura’, ‘Calrose’, and ‘Cayuga’ did not significantly decline under drought stress. Among these five, Wauseon exhibited the lowest reduction in both tuber yield and relative water content under water shortage. The data showed that ‘Wauseon’ is the most attractive cultivar for studies of molecular and physiological processes under drought and for potato breeding due to low yield losses that correspond with high RWC values. This cultivar can serve as a reservoir of potentially useful genes to develop cultivars with enhanced tolerance to this abiotic stress. 相似文献
39.
Beata Laczynska Krystyna Demska‐Zakes Mohammad Abdul Momin Siddique Dorota Fopp‐Bayat 《Aquaculture Research》2020,51(9):3623-3630
Larval growth and gonadal differentiation of gynogenetic sterlet Acipenser ruthenus were studied. The gynogenetic fish were produced by activation of albino sterlet eggs with UV‐irradiated sperm (collected from healthy coloration specimens), following by a heat shock of 34°C. Embryos were reared at 18.0 ± 0.5°C in a recirculation system and initially fed with Artemia sp. for 4 weeks and then fed with formulated feed. During the experiment, the length and weight of fish were recorded for the gynogenetic and control groups. Additionally, the analysis of gonadal sex differentiation was conducted with a 2‐week interval at 289, 303, 317, 331, 345 and 373 DPH. The mean body weight of the control group was significantly higher (p < .05) than the gynogenetic group only at 345 and 373 DPH, while the mean total body length was significantly higher at 331 and 345 DPH (p < .05). The gonad investigation was started at 289 DPH, and ~80% of females were found in the gynogenetic group during the trial period while the number of females and males was similar at 303, 331 and 373 DPH in the control group. The first symptoms of morphological differentiation appeared at 289 DPH, and the final shaping macroscopic structure of the gonad took place earlier in females than in males. 相似文献
40.
Nace Zidar Sofia Montalv?o ?iga Hodnik Dorota A. Nawrot Ale? ?ula Janez Ila? Danijel Kikelj P?ivi Tammela Lucija Peterlin Ma?i? 《Marine drugs》2014,12(2):940-963
Marine organisms produce secondary metabolites that may be valuable for the development of novel drug leads as such and can also provide structural scaffolds for the design and synthesis of novel bioactive compounds. The marine alkaloids, clathrodin and oroidin, which were originally isolated from sponges of the genus, Agelas, were prepared and evaluated for their antimicrobial activity against three bacterial strains (Enterococcus faecalis, Staphylococcus
aureus and Escherichia
coli) and one fungal strain (Candida albicans), and oroidin was found to possess promising Gram-positive antibacterial activity. Using oroidin as a scaffold, 34 new analogues were designed, prepared and screened for their antimicrobial properties. Of these compounds, 12 exhibited >80% inhibition of the growth of at least one microorganism at a concentration of 50 µM. The most active derivative was found to be 4-phenyl-2-aminoimidazole 6h, which exhibited MIC90 (minimum inhibitory concentration) values of 12.5 µM against the Gram-positive bacteria and 50 µM against E. coli. The selectivity index between S. aureus and mammalian cells, which is important to consider in the evaluation of a compound’s potential as an antimicrobial lead, was found to be 2.9 for compound 6h. 相似文献