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抗除草剂转基因小麦生态安全评估(二)——普通小麦与其近缘植物的属间和种间杂交研究 总被引:3,自引:1,他引:3
以普通小麦为父本,以与小麦亲缘关系较近的黑麦、偃麦草和山羊草等属中7个种的10个品种为母本进行人工杂交,结果表明普通小麦与卵穗山羊草的可交配性最高,其两个品种Ae23和Y100与普通小麦的杂交结实率分别为11.96%和14.10%,与黑麦杂交的结实率最低,授粉496朵,未结1粒,与其他近缘种的杂交结实率介于前二者之间。与倍性高的种相比,二倍体种与普通小麦之间的可交配性要差,其杂种幼胚在培养基上也很难出愈。所得杂种的育性非常低,甚至雌雄蕊均不育。由此看来,自然条件下普通小麦基因漂流到野生近缘种中的可能性非常低,通过转基因小麦田间释放产生“超级杂草”是非常困难的。 相似文献
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Exogenous paraoxonase‐1 during oocyte maturation improves bovine embryo development in vitro 下载免费PDF全文
JAA Rincón EM Madeira FT Campos B Mion JF Silva VA Absalón‐Medina WR Butler MN Corrêa LMC Pegoraro A Schneider 《Reproduction in domestic animals》2016,51(5):827-830
Paraoxonase‐1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry‐over effects of PON1 on pre‐implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml?1 of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml?1, respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose‐dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose‐related positive effects on embryo development rates to blastocysts. 相似文献
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M. ŘÍHA J. KUBEČKA M. PRCHALOVÁ T. MRKVIČKA M. ČECH V. DRAŠTÍK J. FROUZOVÁ E. HOHAUSOVÁ T. JŮZA M. KRATOCHVÍL J. PETERKA M. TUŠER M. VAŠEK 《Fisheries Management and Ecology》2011,18(4):339-347
Abstract Diel changes in littoral fish assemblage were studied in four reservoirs in the Czech Republic (Central Europe). The sampling was performed by beach seining in an unstructured littoral zone. Perch, Perca fluviatilis L., roach, Rutilus rutilus (L.), bream, Abramis brama (L.), carp, Cyprinus carpio L., ruffe, Gymnocephalus cernua (L.), pikeperch, Sander lucioperca (L.), eel, Anguilla anguilla (L.) and A. brama × R. rutilus hybrids exhibited higher densities at night. Only bleak, Alburnus alburnus (L.) exhibited higher densities during the day. The number of species was higher in night hauls, and mean body size of roach and bleak was also higher at night. Diel changes in fish densities resulted in the change in species composition between day and night. The study has implication for the sampling design to assess littoral fish assemblages using beach seine netting and recommends night sampling for a representative assessment or sampling during both diel periods for a robust assessment. 相似文献
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Lipid profiles of canine spermatozoa as revealed via matrix‐assisted laser desorption/ionization mass spectrometry 下载免费PDF全文
LT Braga Jr. NRS Bravo KRA Belaz D Zampieri MN Eberlin VA Conforti 《Reproduction in domestic animals》2016,51(6):1055-1058
In this study, we investigated the ability of matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) to characterize the lipid contents of canine spermatozoa. For that, samples of pure semen were analysed. Indeed, quite comprehensive lipid coverage was observed, and the most abundant phospholipid ions detected were from four phosphatidylcholines, that is those of m/z 760.6; 782.6; 808.6; and 830.6 and one of m/z 725.6 from a sphingomyelin. In conclusion, MALDI‐MS was found to offer an easy, fast, accurate, and sensitive analytical method for lipid profiling in canine spermatozoa and could be used as a tool to select sires by assessing the relationship between sperm lipid profiles and variables such as age and breeding history as well as to study the effects of cryopreservation on lipid contents. 相似文献
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Alastair R Mair BVM&S Cert VA MRCVS Patricia Pawson BVMS Diplomate ECVAA PhD MRCVS Emily Courcier† BVetMed BSc MRCVS & Derek Flaherty BVMS Diplomate ECVAA DVA MRCA MRCVS 《Veterinary anaesthesia and analgesia》2009,36(6):532-538
ObjectiveTo assess the cardiorespiratory and hypnotic-sparing effects of ketamine co-induction with target-controlled infusion of propofol in dogs.Study designProspective, randomized, blinded clinical study.AnimalsNinety healthy dogs (ASA grades I/II). Mean body mass 30.5 ± SD 8.6 kg and mean age 4.2 ± 2.6 years.MethodsAll dogs received pre-anaesthetic medication with acepromazine (0.03 mg kg?1) and morphine (0.2 mg kg?1) administered intramuscularly 30 minutes prior to induction of anaesthesia. Heart rate and respiratory rate were recorded prior to pre-medication. Animals were allocated into three different groups: Group 1 (control) received 0.9% NaCl, group 2, 0.25 mg kg?1 ketamine and group 3, 0.5 mg kg?1 ketamine, intravenously 1 minute prior to induction of anaesthesia, which was accomplished using a propofol target-controlled infusion system. The target propofol concentration was gradually increased until endotracheal intubation was possible and the target concentration at intubation was recorded. Heart rate, respiratory rate and noninvasive blood pressure were recorded immediately prior to induction, at successful intubation and at 3 and 5 minutes post-intubation. The quality of induction was graded according to the amount of muscle twitching and paddling observed. Data were analysed using a combination of chi-squared tests, Fisher's exact tests, Kruskal–Wallis, and anova with significance assumed at p< 0.05.ResultsThere were no significant differences between groups in the blood propofol targets required to achieve endotracheal intubation, nor with respect to heart rate, noninvasive blood pressure or quality of induction. Compared with the other groups, the incidence of post-induction apnoea was significantly higher in group 3, but despite this dogs in this group had higher respiratory rates overall.Conclusions and clinical relevanceUnder the conditions of this study, ketamine does not seem to be a useful agent for co-induction of anaesthesia with propofol in dogs. 相似文献