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Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM  + 10?7, IVM  + 10?9, IVM  + 10?11) and culture media (Experiment 2; Control, IVC  + 10?7, IVC  + 10?9, IVC  + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10?9, IVC  + 10?9, IVM /IVC  + 10?9). In Experiment 1, maturated oocytes from Control and IVM  + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10?7 (43.5%; 56.7%) and IVC  + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10?9. Reactive oxygen species production was greater in the IVM /IVC  + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   
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Plant motility     
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Clover is frequently grown in rotation with cereals in order to increase soil nitrogen. The systemic fungicide triadimefon, widely used against cereal pathogens, is readily taken up from soil by clover and degraded to a single major metabolite. Plant weight and symbiotic nitrogen fixation by Rhizobium trijolii are affected only by concentrations of triadimefon in soil that are much in excess of those likely to be encountered in practice. Triadimefon residues are thus unlikely to affect nitrogen fixation by clover under field conditions.  相似文献   
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We used functional magnetic resonance imaging to demonstrate preserved conscious awareness in a patient fulfilling the criteria for a diagnosis of vegetative state. When asked to imagine playing tennis or moving around her home, the patient activated predicted cortical areas in a manner indistinguishable from that of healthy volunteers.  相似文献   
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Aspects on Hormonal Control of Normal and Induced Parturition in the Dog   总被引:1,自引:0,他引:1  
Average length of gestation on the dog is 63 ± 2 days but may vary between 57-71 days due to the long period of receptivity at oestrus and the extended period of sperm survival in the female genital tract. In contrast to other domestic animals progesterone- and oestrogen concentrations are almost identical in pregnant and non pregnant bitches, except for their rapid decline immediately prior to parturition. Control of luteolysis still poorly understood. Experiments with indomethacin leading to a blockade of the prepartal PgF increase, which commences with the decrease of progesterone, point toward a role of PgF at this stage of pregnancy, which was extended for several days. At physiological conditions first visible signs of parturition were observed at peak-PgF levels, 33.6 ± 17.6 hours after onset of luteolysis, which lasted over 16.8 ± 3.4 hours. Pulse-type releases of oxytocin were only observed after this point of time. To test for the effect of progesterone-withdrawal, four 51-57 days pregnant bitches were treated with the antiprogestin RU 38486 which inhibits the activity of progesterone at the receptor level. In all dogs first visible signs of parturition were observed 33.5 ± 7.5 hours after onset of treatment. However, the process of parturition came to an end after cervical opening and totally only one puppy was born. Different to a normal parturition no increase of PgF was observed. Relaxin levels were not influenced by treatment. These observations suggested that treatment with antiprogestin followed by PgF might be an adequate method to induce parturition in the dog; first experiences seem to confirm this conclusion.  相似文献   
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Lame pigs, up to 12 weeks of age, were necropsied to establish a diagnosis. Of 175 pigs examined, 165 were confirmed to have arthritis by histopathological examination of joint tissues. Lesions were most common in the elbow and tarsal joints and least common in the joints of the feet. Typically, there was severe fibrinopurulent inflammation of synovial membranes regardless of the bacteria isolated. A bacterial aetiology was found in 114 (69%) of the 165 pigs. In arthritic pigs in which an aetiology was established the causative agents were Staphylococcus hyicus ssp hyicus (24.6%), Streptococcus equisimilis (26.3%), Actinomyces pyogenes (13.2%), Staphylococcus aureus (7.9%) and Haemophilus parasuis (7.9%). While gender did not affect the prevalence of arthritis, there was an age influence, most of the pigs culled for arthritis being under 6 weeks of age.  相似文献   
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