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1.
KM Morton SL Catt FK Hollinshead WMC Maxwell G Evans 《Reproduction in domestic animals》2004,39(6):454-461
Cumulus-oocyte complexes from hormone-stimulated 3-4-week-old (n=43) and 6-7-week-old (n=12) prepubertal lambs were matured in vitro and incubated with unsorted, or X- or Y-spermatozoa separated with a high-speed cell sorter (SX MoFlo)frozen-thawed. Presumptive zygotes were then cultured to the blastocyst stage, and transferred to recipients fresh or after cryopreservation (frozen). Oocyte cleavage was higher (p <0.05) with unsorted (515/926, 55.6%) than X- or Y-spermatozoa (261/672, 38.8% and 229/651, 35.2%, respectively) and blastocyst formation (% zygotes) by Day 9 of in vitro culture was lower (p <0.05) for X- (102/261, 39.1%) than unsorted spermatozoa (249/515, 48.3%), but did not differ between Y-spermatozoa (103/229, 45.0%) and unsorted spermatozoa, or between X- and Y-spermatozoa (p >0.05). For fresh embryos, survival to term was 50.0% (3/6) for unsorted, 0.0% (0/6) for X- and 16.7% (1/6) for Y-spermatozoa-derived embryos (p >0.05), and for frozen embryos was 4.0% (2/50) for unsorted, 9.1% (2/22) for X- and 2.9% (1/34) Y-spermatozoa-derived embryos (p >0.05). Of the two lambs born from X-spermatozoa-derived embryos, one was female (50%), and from the two Y-spermatozoa-derived lambs, both were male (100%), demonstrating that lambs can be produced after the transfer of fresh and cryopreserved IVP embryos derived from prepubertal lamb oocytes and frozen-thawed sex-sorted sperm. 相似文献
2.
Brain aluminum distribution in Alzheimer's disease and experimental neurofibrillary degeneration 总被引:31,自引:0,他引:31
Neurofibrillary degeneration is an important pathological finding in senile and presenile dementia of the Alzheimer type. Experimentally, aluminum induces neurofibrillary degeneration in neurons of higher mammals. Aluminum concentrations approaching those used experimentally have been found in some regions of the brains of patients with Alzheimer's disease. 相似文献
3.
Krishnan HB Jang S Kim WS Kerley MS Oliver MJ Trick HN 《Journal of agricultural and food chemistry》2011,59(4):1223-1228
Legumes, including soybeans ( Glycine max ), are deficient in sulfur-containing amino acids, which are required for the optimal growth of monogastric animals. This deficiency can be overcome by expressing heterologous proteins rich in sulfur-containing amino acids in soybean seeds. A maize 27 kDa γ-zein, a cysteine-rich protein, has been successfully expressed in several crops including soybean, barley, and alfalfa with the intent to biofortify these crops for animal feed. Previous work has shown that the maize 27 kDa zein can withstand digestion by pepsin and elicit an immunogenic response in young pigs. By use of sera from patients who tested positive by ImmunoCAP assay for elevated IgE to maize proteins, specific IgE binding to the 27 kDa γ-zein is demonstrated. Bioinformatic analysis using the full-length and 80 amino acid sliding window FASTA searches identified significant sequence homology of the 27 kDa γ-zein with several known allergens. Immunoblot analysis using human serum that cross-reacts with maize seed proteins also revealed specific IgE-binding to the 27 kDa γ-zein in soybean seed protein extracts containing the 27 kDa zein. This study demonstrates for the first time the allergenicity potential of the 27 kDa γ-zein and the potential that this protein has to limit livestock performance when used in soybeans that serve as a biofortified feed supplement. 相似文献
4.
5.
David Karki Karl D. Glover Krishna Bondalapati Padmanaban G. Krishnan 《Cereal Chemistry》2016,93(5):471-477
The unique ability of wheat (Triticum aestivum L.) flour to produce cohesive dough has helped to make it the most widely used cereal crop for bread and other baked food products. Measurement of end‐use qualities, such as loaf volume, is ideally carried out through assessing loaves of bread; however, this is resource intensive. Predictive testing methods are more often utilized to identify wheat genotypes with potentially acceptable loaf volume, although more accurate predictive methods would be beneficial. Our objectives were to study the influence of weather observations on bread loaf volume and flour and dough quality data, to use a neural network (NN) model to predict loaf volume with select input data, and to compare the best multiple regression models identified with their NN counterparts. Weather data collected at 20 days after heading (DAH) showed the highest correlations with bread loaf volume when compared with prior intervals. A NN model containing maximum, minimum, and nighttime temperatures produced the highest coefficient of determination for predicting loaf volume. Our results showed that the NN model explained up to 20% more loaf volume variation than a similar regression model. Weather parameters representing conditions at 20 DAH played a significant role in loaf volume prediction. 相似文献
6.
In this study, energy absorption capacity, flexural and dynamic properties of flax fibre reinforced epoxy polymer composite (FFRP) tubes are investigated. The energy absorption capacity of the tubes is investigated under uniaxial compression. Flexural behaviour of the tubes is studied under four-point bending and the dynamic properties (i.e., natural frequency and damping characteristics) are evaluated by impact hammer vibration testing of the tube specimens. The damping characteristics of the tubes are determined by using both a logarithmic decrement curve and the half-peak bandwidth method. The influence of tube laminate thickness and specimen size on the mechanical properties of FFRP tubes is determined. Compressive testing indicates that the FFRP tube provides a specific absorbed energy of 22 J/g, which is close to the conventional metal energy absorption materials, i.e. stainless steel and aluminium tubes. Flexural study shows that the FFRP tube exhibits a brittle failure as similar to that of the FFRP composites in a flat-coupon tension. The load carrying capacity and deflection of the tube increase with an increase in the tube thickness. Impact loading test concludes that an increase in tube thickness leads to a reduction in natural frequency and damping ratio of the tubes. The FFRP tubes have sizedependent dynamic properties, i.e. an increase in tube size increased the natural frequency but reduced the damping ratio of the specimens remarkably. However, all FFRP tubes have high damping ratios, thus reducing the effect of dynamic loading on the structural response. Therefore, this study suggests that FFRP tubes could be used in several structural applications, i.e. in automotive as energy absorbers and in civil infrastructure as poles. 相似文献
7.
Bhutia Nangsol D. Sureja Amish K. Munshi A. D. Verma Manjusha Arya Lalit Krishnan S. Gopala Gurung B. 《Genetic Resources and Crop Evolution》2022,69(7):2485-2500
Genetic Resources and Crop Evolution - Luffa hermaphrodita Singh & Bhandari, known as Satputia, a semi-wild taxon originating from L. graveolens is an underutilized vegetable. It has a... 相似文献
8.
Bennett JO Krishnan AH Wiebold WJ Krishnan HB 《Journal of agricultural and food chemistry》2003,51(23):6882-6886
Soybean (Glycine max [L.] Merr.) protein and oil qualities, with respect to monogastric nutrition, have been linked to the relative abundance of specific protein subunits and fatty acids, respectively. An analysis of field-grown soybean seeds by near-infrared spectroscopy revealed significant differences in their protein and oil contents as a function of nodal position. Seed proteins from the plant apex were high in protein and low in oil content, while those from the basal region exhibited an opposite pattern of accumulation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total seed proteins revealed that the beta-subunit of beta-conglycinin content was 4-fold higher in seeds from the apical nodes than in seeds from basal nodes. The glycinin A3 polypeptide content gradually increased in successively lower nodes from the top of the plant. Its accumulation was drastically reduced when nitrogen was applied at specific growth stages. Exogenous nitrogen did not alter the pattern of beta-subunit accumulation, but accrual of the acidic and basic polypeptides of glycinin was diminished. The remaining seed storage protein components were not influenced by nodal position or nitrogen application. Gas chromatographic analysis of fatty acids indicated that only oleic (18:0) and linoleic (18:2) acids showed variability in accumulation at different nodes. Neither the abundance nor the distribution of the fatty acids was altered by nitrogen application. 相似文献
9.
J. Praveenraj P. Ezhil Praveena T. Bhuvaneswari A. Navaneeth Krishnan K. P. Jithendran 《Aquaculture International》2018,26(2):617-627
Betanodaviruses are the causative agents of the disease known as viral nervous necrosis (VNN) or viral encephalopathy and retinopathy (VER) in a variety of marine and freshwater fish species. The aim of this study was to demonstrate experimental infection of an isolate of betanodavirus (RGNNV genotype) in freshwater fish, Gambusia affinis, for elucidation of transmission mechanism and potential use as a laboratory model. Morbidity and mortality rate was significantly higher by injection route of infection as compared to immersion by bath and resembled the natural infection of juvenile marine fish. The fish in disease affected group showed severe neurological disorders accompanied by extensive vacuolar degeneration and mild to moderate neuronal necrosis of the brain in comparison to control. Amplification of ~?427 bp product in the variable region of the coat protein gene of betanodavirus was achieved by RT-PCR with 100% sequence homology to RGNNV genotype. 相似文献
10.
KM Blackwood 《Science (New York, N.Y.)》1996,273(5277):909-912
Side-chain ferroelectric liquid crystalline polymers are currently used in a number of applications, including displays and electrical sensors. Comparisons with existing technologies and materials indicate that relative to ceramics, such polymers have lower figures of merit but offer greater durability in sensor applications. 相似文献