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排序方式: 共有117条查询结果,搜索用时 15 毫秒
1.
Mouse pronuclear stage embryos with intact slit zona pellucida (manipulated) were cultured in vitro until the hatched blastocyst stage in simplex optimized medium with higher K+ concentration (KSOM) prepared with three different water types: tap, deionized reverse osmosis (D‐O) water and Milli‐Q system (M‐Q) water. The culture media were supplemented with or without protein and ethylenediaminetetraacetic acid (EDTA, disodium salt). The rates of hatched blastocysts were significantly affected (p < 0.01) by micromanipulation, protein supplement and water source. The water source has no influence (p > 0.05) on development in EDTA‐supplemented protein‐free culture media, whereas in EDTA‐ and protein‐free culture media, the water quality significantly (p < 0.001) affected the rates of development, with higher rates in media prepared with M‐Q water. The micromanipulated embryos showed higher sensitivity to the water quality (p < 0.01). It worth mentioning that the rates of hatched blastocysts in protein‐free culture media were very low (0–7.5%). Furthermore, the three different water types were analysed by measuring the electrical conductivity, inorganic ions, total organic carbon and endotoxins to evaluate the purity. M‐Q water showed the lowest levels of inorganic ion, total organic carbon and endotoxin concentrations. We concluded that manipulated mouse embryos are good system to evaluate the quality of water used in biological system. 相似文献
2.
Ariana M.P. Nap Yvonne W.E.A. Pollak Walter E. van den Brom Ad Rijnberk DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):302-303
Thyroidal 99m TcO4 (pertechnetate) uptake percentages were determined in unanesthetized euthyroid (n = 13) and hyperthyroid (n = 18) cats. Maximal uptakes were observed 60 minutes after IV injection of the radionuclide and ranged from 0.3 to 3.9% of the dose in euthyroid cats (median 2.23%) and from 5.2% to 23.9% of the dose in hyperthyroid cats (median 14.8%) ( P < .05). There were no overlaps in pertechnetate uptake percentages during any of the intervals evaluated. It is concluded that the optimal time for visualization of the thyroid by 99m TcO4 -scanning is 60 minutes after IV injection of the radionuclide. Calculation of the percentage uptake is of additional diagnostic value. 相似文献
3.
ACE inhibition in goats under fixed‐time artificial insemination protocol increases the pregnancy rate and twin births 下载免费PDF全文
VP Fernandes Neto MNN Silva AS Costa D Kunkel AS Júnior LCS Feitosa MCS Muratori APR Costa 《Reproduction in domestic animals》2018,53(4):1006-1008
To assess the effect of the angiotensin‐converting enzyme (ACE) inhibition on the efficiency of the fixed‐time artificial insemination (TAI), 69 goats were divided randomly into two groups: enalapril (n = 35) and control (n = 34). In the experiment, all animals underwent the protocol of fixed‐time artificial insemination for 12 days. Enalapril group received enalapril maleate dissolved in saline (Enalapril, Lab Teuto Ltda) subcutaneously at the following doses: 0.2 mg/kg/day in D0‐D2; 0.3 mg/kg/day in D3‐D6 and 0.4 mg/kg/day in D7‐D11. The control group received the corresponding volume of 0.9% saline solution. We performed a single insemination 36 hr after sponge removal using frozen semen from two adult male goats with recognized fertility. The ultrasound pregnancy diagnosis was 30 days after the artificial insemination (AI). There was significant increase in pregnancy rates and twinning as well as a decrease in foetal loss in animals receiving enalapril (p < .01). The use of ACE inhibitors during the TAI protocol was shown to be a promising alternative to increase the efficiency of such reproductive biotechnology. 相似文献
4.
OHO Eckhardt SMMK Martins ME Pinese FC Horta AC Rosseto MA Torres AFC De Andrade BBD Muro CT Marino PHM Rodrigues AS Moretti 《Reproduction in domestic animals》2014,49(6):964-969
The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation. 相似文献
5.
Phenotypic and genotypic analysis of a commercial cultivar and wild populations of Anemone coronaria
Yonash Nissim Fang Jinggui Shamay Arik Pollak Neta Lavi Uri Cohen Avner 《Euphytica》2004,136(1):51-62
Seven wild populations of Anemonecoronaria were assessed for 11 phenotypic traits, most of them having economic value for the flower industry. The wild populations
were sampled to represent the diversity in habitats, climates, rock and soil types, terrains, and elevations in Israel. AFLP
analysis was carried out on 12 individuals from each of six out of the seven wild populations and for six individuals from
the commercial cultivar ‘Mona-Lisa’. It was found that the Dorot population, which is located in the area bordering the semi-arid
zone at the very end of the species distribution, exhibits extreme and different phenotypes with relatively low variability
compared withthe other wild populations. The other six wild populations, that grow in more favorable geographic and climatic
conditions exhibit phenotypes with larger plants, larger numbers of flowers and less dissected leaves. These populations were
less uniform than that of Dorot. Genetic characterization by AFLP markers revealed a total of 165 bands. The wild populations
exhibit wide variation within-population, with about 80% polymorphic bands and average gene diversity between pairs of about
30%. The Dorot population has the lowest genetic variation and the Megido population the highest. Thus, the phenotypic variation
reflects the genetic variation. The cultivar ‘Mona-Lisa’, as expected, has much lower genetic variation. The Dorot population
and the ‘Mona-Lisa’ cultivar were found to have the largest genetic distances from the other wild populations, and the highest
genetic variation between themselves. Phenetic analysis yielded a dendrogram describing the genetic relatedness of these populations.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
A. Shamay J. Fang N. Pollak A. Cohen N. Yonash U. Lavi 《Genetic Resources and Crop Evolution》2006,53(4):821-829
Single nucleotide polymorphisms (SNPs) were discovered in 44 cDNA clones from leaves by comparison of the commercial cultivar
‘Mona Lisa‘ with a wild population of Anemone coronaria L. One hundred and fifty five SNPs were discovered with an average frequency of one SNP per 167 bp. Forty nine percent of
the SNPs are transitions, 43 are transversions, 26 are heterozygotes and 9% are InDels. Eighty two (68%) of the SNPs located
in the ORF, resulted in a change of amino acid while 39 (32%) did not affect the amino acid. Thirty eight SNPs (46%), which
change the amino acid, resulted in similar amino acid, while 44 SNPs (54%) resulted in a non-similar amino acid. Nine polymorphic
sites were genotyped by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) using
genomic DNA. Phylogenetic analysis of 50 individuals from six wild populations and the commercial cultivar revealed high polymorphism
within and low polymorphism between A. coronaria L. wild populations. The phylogenetic tree revealed only one clear cluster of the ‘Mona Lisa’ cultivar. All the other individuals
from the various wild populations are distributed on different nodes indicating that the genetic variation within the wild
populations is high while the commercial cultivar is quite homogenous and genetically different from all other populations. 相似文献
7.
Components of (co)variance for weaning weight were estimated from field data provided by the American Simmental Association. These components were obtained for the observational components of variance corresponding to a sire, maternal grandsire, and dam within maternal grandsire model. From these estimates, direct additive genetic variance (Sigma2A), maternal additive genetic variance (Sigma2M), covariance between direct and maternal additive genetic effects (SigmaAM), variance of permanent environment(Sigma2pe) and temporary environment variance(Sigma2te) were determined. A procedure to approximate restricted maximum likelihood (REML) estimates of the observational components of variance based on the expectation-maximization (EM) algorithm is described. From these results, phenotypic variance ( ) of weaning weight was 667.88 kg2. Values forSigma2A, Sigma2M, Sigma2pe and Sigma2te were 79,30,58,38,49.45, and 469.97 kg2, respectively. Genetic correlation between direct and maternal additive genetic effects was .16. 相似文献
8.
Theyse LF Hazewinkel HA Terlou M Pollak YW Voorhout G 《American journal of veterinary research》2006,67(5):790-795
OBJECTIVE: To quantitatively assess distraction-induced bone formation in a crural lengthening model in dogs by use of delayed-image bone scintigraphy. ANIMALS: 12 mature Labrador Retrievers. PROCEDURE: Dogs were randomly allocated to 1 of 3 groups. A circular external skeletal fixation system was mounted on the right crus of each dog. Osteotomy of the distal portion of the tibia and fibula was performed in groups 1 and 2 and was followed by a lengthening procedure of 10 mm in the first group only. The third group served as sham-operated controls. Delayed-image bone scintigraphy with technetium-99m hydroxy methylene diphosphonate was performed 2, 4, and 6 weeks after surgery. Delayed-image-to-region-of-interest, delayed-image-to-crural, and delayed-image-to-femoral scintigraphic activity ratios were calculated. New bone formation was quantified by use of densitometric image analysis, and values for the scintigraphic ratios were compared. RESULTS: In the distraction and osteotomy groups, delayed-image-to-region-of-interest and delayed-image-to-crural ratios increased significantly. Although densitometric image analysis revealed increased bone formation after distraction, the region-of-interest ratios and crural ratios were similar in both groups. All dogs had increased delayed-image-to-femoral ratios. CONCLUSIONS AND CLINICAL RELEVANCE: Delayed-image bone scintigraphy ratios were not effective at differentiating between the amounts of distraction-induced bone and osteotomy-induced bone. Metabolic bone activity in the adjacent femur was increased as a consequence of circular external skeletal fixator placement. Delayed-image bone scintigraphy was not adequately sensitive to quantitatively monitor bone formation but may be useful as an early predictor of bone healing. 相似文献
9.
Use of cross incompatibility in corn (Zea mays L.) by the Ga1-s allele may reduce cross-fertilization in specialty and conventional organic corn with pollen from genetically-modified (GM)
corn. For effective use, information about environment, and genotype × environment effects on cross-fertilization by ga1 as well as heritability of cross incompatibility in maize is necessary. Our objective was to obtain this information. Four
population pairs differing in their genotype at ga1 were evaluated for cross incompatibility with ga1 pollen in different environments. Populations were derived by crossing the recurrent parents B116, PHG35, ARZM16035:S19,
and (CHZM05015:Mo17)Mo17 to Ga1-s donor parent Mo508W/Mo506W. Two replicates of each treatment were grown in the center of 952 m2 fields planted with purple corn as an adventitious source of ga1/ga1 pollen. Open pollination was allowed and the amount of cross-fertilization estimated by averaging the percentage of purple
seeds. Environment and genotype × environment effects were not significant. Contrasts to evaluate differences in cross-fertilization
between Ga1-s and ga1 populations revealed that mean percentages of cross-fertilization in Ga1-s populations of B116, ARZM16035:S19, and (CHZM05015:Mo17)Mo17 were significantly lower than in ga1 populations. The estimated broad-sense heritability on an entry-mean basis for cross incompatibility was 0.81. Results suggest
differences in genotype at ga1 played a major role in cross-fertilization of populations differing in their genotype at the ga1 locus. Incompatibility may be selected effectively over different environments and the Ga1-s system may be of value to reduce cross-fertilization with GM corn pollen. 相似文献
10.