Antibiotics and infectious serositis in White Pekin ducklings     

W J Ash 《Avian diseases》1967,11(1):38-40

  相似文献   

Genetic divergence in two tropical maize composites after four cycles of reciprocal recurrent selection          下载免费PDF全文

Adesike O. Kolawole  Abebe Menkir  Melaku Gedil  Essie Blay  Kwadwo Ofori  Jennifer G. Kling 《Plant Breeding》2017,136(1):41-49

Two tropical maize composites were subjected to four cycles of reciprocal recurrent selection to develop divergent inbred lines with good combining ability. This study was conducted to examine the extent of genetic diversity, changes in allele composition and genetic structure, of 100 randomly selected S₁ lines each from the original (C₀) and advanced (C₄) selection cycles of TZL COMP3 and TZL COMP4, genotyped using single nucleotide polymorphism (SNP) markers. Results revealed that the proportion of alleles at both low and high frequencies decreased from C₀ to C₄, whereas those at intermediate frequencies increased at C₄ in the two composites. More unique and other alleles were lost at C₄ in TZL COMP3 relative to those in TZL COMP4. The changes in different measures of genetic diversity were either small or negligible with selection in the two composites. The proportion of markers departing from Hardy–Weinberg equilibrium (HWE) decreased with selection, whereas the total number of pairs of markers in linkage disequilibrium increased with selection in the two composites. Examination of changes in population structures using a model‐based approach as well as cluster and multivariate analyses found a high degree of concordance in stratifying the 400 S₁ lines into four non‐overlapping groups corresponding to the two selection cycles each within the reciprocal composites. The observed molecular‐based divergence between cycles within the same composite and the clear differentiation between the complementary composites highlight the importance of reciprocal recurrent selection for preserving genetic diversity for long‐term selection. This increases the potential of the advanced selection cycles to sustain genetic gain in productivity of hybrids adapted to the savannas in West and Central Africa.  相似文献   

Assay variability and storage stability of the myeloperoxidase index of the ADVIA 2120i hematology analyzer in canine and equine whole blood samples     

Shelley Ann Ash Chu  Tracy Stokol 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2021,50(1):28-36

  相似文献   

ON DUTY-FREE IMPORTATION     

Ash CH 《Science (New York, N.Y.)》1919,50(1281):55-58

  相似文献   

Genetic diversity and population structure analysis of Grass pea (Lathyrus sativus L.) accessions collected from North-Western Ethiopia using SSR markers     

Mekonen  Desalegn Abebe  Abraham  Adane  Oselebe  Happiness  Afiukwa  Celestine  Ilesanmi  Oluyinka  Abebe  Tiegist Dejene 《Genetic Resources and Crop Evolution》2022,69(3):1247-1260

Genetic Resources and Crop Evolution - Grass pea (Lathyrus sativus L.) is a legume crop known to be an excellent source of protein, tolerant to drought, waterlogging, and salinity. The crop is used...  相似文献   

Irreversible inhibition of nuclear exoribonuclease by thymidine-3'-fluorophosphate and p-haloacetamidophenyl nucleotides   总被引：5，自引：0，他引：5  

M B Sporn  D M Berkowitz  R P Glinski  A Ash  C L Stevens 《Science (New York, N.Y.)》1969,164(886):1408-1410

Exoribonuclease purified from Ehrlich ascites tumor cell nuclei and in intact HeLa cell nuclei is irreversibly inactivated by tow concentrations of p-bromo- and p-iodoacetamidophenyl nucleotides and by thymidine-3'-fluorophosphate. Iodoacetate, bromoacetate, and thymidine-5'-fluorophosphate do not affect the enzyme. Although p-haloacetamidophenyl nucleotides inactivate ribonucleic acid polymerase of isolated HeLa cell nuclei, thymidine-3'-fluorophosphate does not affect the activity of this enzyme in vitro.  相似文献   

Ascorbic acid: cofactor in rabbit olfactory preparations   总被引：2，自引：0，他引：2  

K O Ash 《Science (New York, N.Y.)》1969,165(896):901-902

A stimulant-induced decrease in absorbance at 267 nanometers in preparations from rabbit olfactory epithelium requires ascorbic acid as a cofactor. Vitamin C is bound to proteins in the olfactory mucosa in vivo. When the stimulant. 3,7-dimethyl-6-octen-3-ol interacts with olfactory proteins, it triggers a change in protein conformation which renders ascorbic acid available for oxidation. The specific decrease in absorbance at 267 nanometers is produced when the "freed" ascorbic acid is oxidized.  相似文献   

Reimagining cities. Introduction     

Ash C  Jasny BR  Roberts L  Stone R  Sugden AM 《Science (New York, N.Y.)》2008,319(5864):739

  相似文献   

Trypanosomatid genomes. Introduction     

Ash C  Jasny BR 《Science (New York, N.Y.)》2005,309(5733):399

  相似文献   

Grazing Management in Tropical Savannas: Utilization and Rest Strategies to Manipulate Rangeland Condition     

Andrew J. Ash  Jeff P. Corfield  John G. McIvor  Taoufik S. Ksiksi 《Strength and Conditioning Journal》2011,64(3):223-239

Grazing management is important for sustaining the productivity and health of rangelands. However, the effects of grazing management on herbage growth and species composition in the tropical savannas of northern Australia are not well known. In this eight-year study the influences of utilization rate and resting pastures from grazing on vegetation dynamics were measured at three sites in northeast Queensland, Australia. The sites had high, medium, and low soil fertility, and there were two land condition classes (States I and II) at each site. Severe drought occurred during the first four years, but above-average rainfall was received in the second half of the study. High utilization rates reduced biomass, perennial grass basal area, and ground cover. The reduction in biomass was due to both higher consumption and decreased primary production. State I condition plots at the high and medium soil fertility sites were initially dominated by decreaser perennial grasses, but these declined at all utilization levels, particularly the high rate. They were largely replaced by exotic perennial grasses. At the low fertility site there were no exotic grasses, and the decreaser grasses increased in all treatments, with the increases greatest in plots with low utilization or medium utilization plus resting. In the State II condition plots at the high and medium fertility sites, low or moderate utilization, led to an increase in both decreaser and exotic perennial grasses; with high utilization the decreaser perennial grasses declined and were replaced largely by exotic perennial grasses. This study clearly demonstrated that either conservative stocking with year-round grazing or a grazing system that includes some wet-season resting will help maintain land in a desirable state or help facilitate the transition from a less desirable ecological state to one more desirable for pastoral production and rangeland condition.  相似文献