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51.
52.
Albert L. Elder Dorothy M. Rathmann Thomas F. Conway 《Plant foods for human nutrition (Dordrecht, Netherlands)》1964,11(1):67-77
Summary The oil contents of single kernels of corn can be determined by wideline nuclear magnetic resonance spectroscopy. Since this analytical procedure does not alter seed composition or viability, it could accelerate the development of crops having higher oil contents. A highly significant correlation was found between the oil contents of single kernels of corn and their progeny ears. This indicates that single-kernel differences in oil content are heritable. The importance of this development in terms of the increasing world-wide demand for polyunsaturated oils is discussed.
with 4 figs.
Paper presented at 6th International Congress of Nutrition, Edinburgh, August 9–15, 1963. 相似文献
Zusammenfassung Der Öl-Gehalt einzelner Maiskörner kann durch kernmagnetische Resonanz-Spektroskopie festgestellt werden. Da dieses analytische Verfahren weder die Samenzusammensetzung noch die Lebensfähigkeit des Samens ändert, könnte sie dazu benutzt werden, die Entwicklung von Maisbeständen mit höherem Ölgehalt zu beschleunigen. Es wurde eine höchst beachtliche Korrelation zwischen dem Ölgehalt der einzelnen Kerne und dem der daraus entstehenden Kerne gefunden. Dies weist darauf hin, daß Einzel-Kern-Unterschiede im Ölgehalt vererbbar sind. Die Bedeutung dieser Entwicklung in Bezug auf die weltweite Nachfrage nach mehrfach ungesättigten Ölen wird besprochen.
Résumé La quantité d'huile contenue dans les grains de maïs isolés peut être déterminée par la spectroscopie à résonance magnétique nucléaire à grande amplitude. Comme ce procédé ne cause aucune altération de la composition ou de la viabilité de la semence il pourrait accélérer la production de récoltes a rendement d'huile élevé. Une corrélation très étroite a été établie entre la quantité d'huile contenue dans les grains individuels et celle contenue dans leur progéniture. Ceci indique que la difference entre les quantités d'huile contenues dans deux grains individuels peut-être héritée. Cet article traite de l'importance de cette application scientifique en liaison avec la demande croissante d'huiles polyinsaturées dans le monde entier.
with 4 figs.
Paper presented at 6th International Congress of Nutrition, Edinburgh, August 9–15, 1963. 相似文献
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I Garcia‐Ispierto F Lpez‐Gatius G Bech‐Sbat JL Yniz E Angulo C Maris S Floch A Martino 《Reproduction in domestic animals》2010,45(5):e168-e173
The aim of this study was to investigate the effect of applying a progesterone‐based oestrous synchronization protocol at 51–57 days postpartum in high‐producing dairy cows. The data analysed were derived from 1345 lactating cows. Cows between 51 and 57 days postpartum were assigned to the groups: control, PRID (receiving a progesterone‐releasing intravaginal device for 9 days, and prostaglandin F2α 24 h before PRID removal) or GnRH–PRID (the same as the PRID group plus GnRH at PRID insertion). Oestrus was detected by using pedometers and confirmed by examination of the genital tract at AI. Oestrous and conception rates before days 71–77 postpartum, pregnancy loss in early pregnant cows or the cumulative conception rate registered on day 120 postpartum were considered as the dependent variables in four consecutive logistic regression analyses. Based on the odds ratios, the oestrous rate increased by a factor of 1.73 in cows showing oestrus before treatment for each unit increase in the number of previous oestruses; decreased by a factor of 0.44 in the control group with respect to the treatment groups; and by a factor of 0.61 in cows without luteal structures at treatment with respect to cows with corpora lutea. The conception rates of cows inseminated before days 71–77 postpartum remained similar across the groups, whereas the likelihood of pregnancy loss for cows becoming pregnant during this period was 0.11 times lower in the PRID group than in the control. Based on the odds ratio, the likelihood of a higher cumulative conception rate on day 120 postpartum: increased in cows showing oestrus before treatment by a factor of 1.41 for each unit increase in the number of previous oestruses, was reduced 0.56‐fold in control cows compared with treated cows, and was also reduced by a factor of 0.98 for each kilogram of milk production increase recorded at treatment. In conclusion, although oestrous synchronization programmes performed in this study did not improve fertility, cows treated with progesterone could be inseminated earlier than untreated cows, such that the treatments increased the cumulative pregnancy rates determined on day 120 postpartum. In addition, fewer pregnancy losses were observed in early pregnant cows in the PRID group than the GnRH–PRID group. 相似文献
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C Feltrin CA Cooper N Mohamad‐Fauzi VHV Rodrigues LH Aguiar S Gaudencio‐Neto LT Martins CEM Calderón AS Morais IS Carneiro TM Almeida ING Silva JL Rodrigues EA Maga JD Murray AB Libório LR Bertolini M Bertolini 《Reproduction in domestic animals》2014,49(4):648-656
The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona‐free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre‐treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona‐free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo‐ vs in vitro‐matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona‐free and zona‐intact goat cloned embryos. 相似文献
57.
Chromatographic fractionation of crude extracts (C8 extracts) from the protein-enriched flour of commercial field peas (Pisum sativum L.) has been shown here to yield peptide mixtures related to the pea albumin 1b (PA1b) family of cysteine-rich plant peptides. The mixtures were obtained initially by flash chromatography with silica gel. Following elution of soyasaponins and lysolecithins, the end fractions obtained with the use of two flash chromatographic solvent systems displayed activity in a flour disk antifeedant bioassay with the rice weevil [Sitophilus oryzae (L.)]. Chemical properties of these mixtures were compared by thin-layer chromatography, high-performance liquid chromatography (HPLC), IR, MS, and amino acid analyses. The major peptides of C8 extracts, with average masses of 3752, 3757, and 3805 Da, were isolated by anion exchange chromatography. Samples enriched in the peptide of mass 3752 were isolated by cation exchange chromatography. Reduction plus alkylation experiments in combination with electrospray ionization mass spectrometry showed that C8 extracts contained about 10 peptides and, like PA1b, each peptide possessed six cysteine residues (three disulfide bonds). Disulfide bond reduction with 2-mercaptoethanol destroyed the antifeedant activity. The native peptides of C8 extracts were found to be resolved into nine peaks with XTerra HPLC columns operating at alkaline pH. These columns were employed to assess the distribution of pea peptides in the isolated fractions, with photodiode array and electrospray detection. 相似文献
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JL O'RIELLY 《Australian veterinary journal》1993,70(12):442-444
SUMMARY: The IgG concentration of plasma from 13 mares was measured by radial immunodiffusion when fresh and after storage at -4°C and thawing by 3 methods. There was no significant (P > 0.05) reduction in the IgG concentration when plasma was thawed over 6 hours at 22°C (1352.9 ± 101.6 mg/dL) (mean ± SEM) compared with the fresh sample (1369.5 ± 88.1 mg/dL). In contrast, there was a significant (P < 0.05) reduction in the IgG concentration of plasma that was rapidly thawed at 57°C over 50 minutes (1142.9 ±66.2 mg/dL), or placed in a microwave oven for 20 to 25 minutes (1093.4 ± 74.4 mg/dL). When plasma is administered to hypo-gammaglobulinaemic newborn foals, a larger volume is required when thawing is rapid than when thawing is slow or when fresh plasma is administered. 相似文献
60.