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981.
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Summary An aneuploid hybrid (2n=23) of Fragaria moschata (2n=42) and Potentilla fruticosa (2n=14) was backcrossed with pollen of both parents, separately and combined in a pollen mixture. Seven vigorous progeny were obtained. The origin of the exeptional chromosome numbers, 2n=44, 49, 63, 63, 65, 67, 67, is discussed, and it is shown that each of the numbers could be produced by the fertilisation of unreduced and double unreduced gametes of the hybrid by normally reduced gametes of one of the parental species. 相似文献
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984.
Analyses of seeds from a wide range of pea lines have revealed extensive variation for all of the major fatty acids normally found in pisum. Unlike total lipid content, this variation was not affected by the presence of mutant alleles at the r and rb loci. To allow chemically analysed seed to be used in crosses, which is of particular importance for F2 seed, a method has been developed by which individual seeds can be analysed non-destructively. This system entails drilling a small hole in the seed, away from the embryonic axis. The small quantity of powder produced by this process can be used for the chemical analysis but does not prevent the seed from being grown to produce progeny. Reducing the sample size had no significant effect upon the compositional analysis of the fatty acids. 相似文献
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A. R. E. Jones C. A. Ragle N. A. Huggons A. A. Tibary 《Equine Veterinary Education》2020,32(10):e189-e193
The objective of this retrospective study was to describe the use of bilateral laparoscopic ovariectomy without hysterectomy for chronic pyometra in horses. Four client-owned horses were included, each having chronic pyometra that was unresponsive to treatment. Bilateral laparoscopic ovariectomy was performed on the horses under standing sedation. A final uterine lavage was performed either 24 hours before or after surgery, with no further treatment of the uterus. No complications were encountered during surgery or post-operatively, and each horse had resolution of the pyometra without recurrence of clinical signs over at least 3 years. All owners were satisfied with the procedure. Following histopathology, one horse was found to be a true hermaphrodite, with one vestigial testis and one ovotestis. Ovariectomy alone was an effective treatment for four horses with chronic pyometra, without complications. Ovarian steroids and abnormal uterine or cervical conformation are important influences in the pathogenesis of pyometra, and removal of the hormone source via ovariectomy should be considered to avoid a more invasive surgery and the potential complications associated with ovariohysterectomy in horses. 相似文献
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