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31.
32.
Maher?Medini Sonia?HamzaEmail author Ahmed?Rebai Michael?Baum 《Genetic Resources and Crop Evolution》2005,52(1):21-31
Thirty-four durum wheat cultivars representing the Tunisian durum (Triticum durum Desf.) wheat collection and seven wild species of wheat relatives (Triticum turgidum L., T. dicoccon Schrank., T. dicoccoides (Körn) Schweinf., T. araraticum Jakubz., T. monococcum L., Aegilops geniculata Roth, and Aegilops ventricosa Tausch) were analysed with amplified fragment length polymorphism (AFLP) and microsatellite (SSR) markers. Both marker systems used were able to differentiate durum wheat cultivars from the wild relatives and to specifically fingerprint each of the genotypes studied. However, the two marker systems differed in the amount of detected polymorphisms. The 15 SSR markers were highly polymorphic across all the genotypes. The total number of amplified fragments was 156 and the number of alleles per locus ranged from 3 to 24 with an average of 10.4. Two SSR markers alone, Xwms47 and Xwms268, were sufficient to distinguish all 34 durum wheat genotypes. The five AFLP primer pair combinations analysed yielded a total of 293 bands, of which 31% were polymorphic. The highest polymorphic information content (PIC) value was observed for SSRs (0.68) while the highest marker index (MI) value was for AFLPs (7.16) reflecting the hypervariability of the first and the distinctive nature of the second system. For durum wheat cultivars, the genetic similarity values varied between 31.3 and 81% for AFLPs (with an average of 54.2%), and between 3.6 and 72.7% for SSRs (with an average of 19.9%). The rank correlation between the two marker systems was moderate, with r = 0.57, but highly significant. Based on SSR markers, highest genetic similarity (GS) values were observed within the modern cultivars (37.3%), while the old cultivars showed a low level of GS (19.9%). Moreover, the modern cultivars showed low PIC and MI values. UPGMA Cluster analysis based on the combined AFLP and SSR data separated the wild wheat species from the durum wheat cultivars. The modern cultivars were separated from the old cultivars and form a distinct group. 相似文献
33.
Mohammed I. Saleh Ziad Y. Abu‐Waar Muhanad W. Akash Maher Al‐Dabbas 《Cereal Chemistry》2014,91(6):603-609
Rice flour composition played a key role in determining the changes in pasting properties of rice flour. The influence of incorporating defatted rice bran (DFRB), rice bran fiber (RBF), rice bran protein (RBP), and stabilized rice bran (SRB) fractions on the mechanism of rice flour pasting viscosities was investigated. Pasting properties of long‐ and medium‐grain rice flour substituted with 5, 10, 15, 20, and 100% bran fractions resulted in a significant decrease (P < 0.05) in rice flour pasting property values. Flour substituted with RBP had the lowest pasting property measurements compared with other fractions, and the greater the percentage substituted, the lower the pasting property values. DFRB and RBF were least affected properties when used as a replacement. Results were attributed to the contribution of rice starch in the mechanism of rice paste formation, in which decreasing starch in a rice flour sample, as a result of substituting with fractions of SRB, may have resulted in faster swelling of starch granules to the maximum extent and increased their susceptibility to be disrupted by shear, resulting in low paste viscosities. Results also suggested that protein structural integrity and the nature of starch–protein bonding affected rice flour pasting mechanism formation. 相似文献
34.
SUMMARY Thirteen Tammar wallabies (Macropus eugenii) were dosed orally with 500, 1000 or 10 000 oocysts of Toxoplasma gondii, as part of a vaccination trial. Eleven animals died of acute toxoplasmosis 9 to 15 days after challenge. The lesions were similar in all animals, consisting of foci of necrosis and inflammation in the intestines, lymphoid tissue, adrenal cortex, heart, skeletal muscle and brain, and severe generalised pulmonary congestion and oedema. Free and intracellular tachyzoites of Toxoplasma were associated with the lesions. The remaining 2 animals had shown no signs of disease when euthanased four months after challenge. Small, focal, non-suppurative inflammatory lesions were seen in brain, heart and skeletal muscle of these animals and chronic Toxoplasma infection was confirmed by mouse inoculation. 相似文献
35.
Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby 总被引:1,自引:0,他引:1
DK Yeomans J Barriot DW Dunham RW Farquhar JD Giorgini CE Helfrich AS Konopliv JV McAdams JK Miller WM Owen DJ Scheeres SP Synnott BG Williams 《Science (New York, N.Y.)》1997,278(5346):2106-2109
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter. 相似文献
36.
Enrichment techniques and serological strain typing methods were used to determine the source of stem and progeny tuber populations ofErwinia carotovora (Ec) in 1980 and 1981. Plots were established in a field that had been planted with potatoes since 1972. Seed tubers of cultivars Russet Burbank and Norgold Russet were assayed forErwinia carotovora pv.carotovora (Ecc) andErwinia carotovora pv.atroseptica (Eca) by tuber peeling and direct plating and plating following enrichment in a pectate-based broth. Levels of seed tuber infestation ranged from undetectable to 2.4 × 104 colony-forming units per g peel tissue. Prior to planting Ecc was detected in soil samples from field plots by enrichment in a pectate-based broth. Ec was isolated from symptomless plants with increasing frequencies from 8 weeks following planting regardless of the level of Ec populations in seed tubers. At harvest progeny tuber recontamination was low and not related to levels of seed tuber Ec populations. In 1980, serological typing of representative Ecc isolates indicated serogroups III, XXIX, and unknown strains isolated from the soil but not the seed tubers prior to planting were isolated from stems and progeny tubers. Serogroup XXIX was isolated from soil, seed, stems and progeny tubers in 1981. Throughout both years, Ecc was isolated more frequently than Eca from seed, soil, stems, and progeny tubers. These data emphasize the potential for reinfestation of seed stocks and infection of plants by populations of Ecc that overwinter in soil under Wisconsin conditions. 相似文献
37.
Alharbi KB Al-Swailem A Al-Dubaib MA Al-Yamani E Al-Naeem A Shehata M Hashad ME Albusadah KA Mahmoud OM 《Tropical animal health and production》2012,44(1):173-177
Camels are the prime source of meat and milk in many desert regions of the world including Saudi Arabia. Paratuberculosis
of camels, locally called Silag, is a serious and invariably fatal disease in the Arabian camel. Six camels were used in this
study. Five camels with clinical paratuberculosis were used to study the pathology of the disease and confirm its aetiology.
The sixth camel was clinically healthy and used as a control. The camels were examined clinically and bled for haematological
and blood chemistry analysis. They were then humanely killed with a high intravenous dose of thiopental sodium (10 mg/kg)
for pathological studies as well as obtaining tissues for microbiological and molecular studies. The clinical signs of the
disease were emaciation, diarrhoea, alopecia, wry neck and pale mucous membranes. Laboratory diagnosis showed reduced haemoglobin
concentration, low haematocrit and high activity of the serum enzyme alanine aminotransferase. Serum creatinine concentration
was normal. These results indicated the infected camels were anaemic and the function of their livers was affected. Postmortem
examination showed thickened and corrugated intestinal mucosa, enlarged granulomatous mesenteric lymph nodes, miliary and
diffuse granulomas in the liver (in four camels), generalized lymph node granulomas (in one camel), splenic granuloma (in
one camel) and mediastinal lymph node granuloma (in two camels). Histopathological examination showed diffuse infiltration
of macrophages in all organs showing lesions. Ziehl–Neelsen staining of tissue scraping and tissue sections showed masses
of acid fast bacilli, except for the spleen. Infection with Mycobacterium avium subsp. paratuberculosis was confirmed by PCR by targeting the IS900 gene. 相似文献
38.
Agroforestry is a leading alternative for food security and forest conservation. A full understanding of positive and negative,
i.e. allelopathic, interactions between crops and forest trees is necessary for producing crops and conserving forests especially
within the threatened Mediterranean forest ecosystems. The present study explored the allelopathic effects of green and senescent
leaf and soil extracts of two agroforestry trees—Pinus halepensis and Quercus coccifera—on the germination of wheat, barley, lentil, chickpea, and fababean as the major grain crops of Jordan. Results revealed
that allelopathic effects reduced seed germination of these crops. Germination reduction reached a maximum of 75% in fababean
treated with green extracts of Q. coccifera and differed among crops and extract sources, but not between tree species. Comparing between green and senescent leaf and
soil extract, regarding their effect on germination percentage, it was noticed that these effects were similar in some crops
and were different in others. Germination responses were generally different between cereals and legumes where cereals tend
to be less affected by allelopathic influences than legumes, especially fababean. We suggest using cereals such as wheat and
barley in agroforestry practices in the Mediterranean region of Jordan. 相似文献
39.
The effect of 24- and 48-hour storage at room temperature on automated total nucleated cell count (TNCC), differential cell count (DCC) and cell morphology was assessed, and the effect of initial total protein concentration on canine and feline body cavity effusion samples (2 to 5 ml) was evaluated. At 24 and 48 hours, TNCC and absolute numbers of neutrophils, macrophages and small lymphocytes were significantly decreased and numbers of unrecognisable cells were significantly increased. Neoplastic cells and intracellular bacteria identified in fresh samples were missed at 24 and 48 hours. The initial total protein concentration was associated with an effect on percentage of unrecognisable cells and small lymphocytes over time. Change in TNCC over time would have resulted in misclassification of the effusion type in four of 47 samples. 相似文献
40.
Reconstruction of nutrient concentrations in the deep Southern Ocean has produced conflicting results. The cadmium/calcium (Cd/Ca) data set suggests little change in nutrient concentrations during the last glacial period, whereas the carbon isotope data set suggests that nutrient concentrations were higher. We determined the silicon isotope composition of sponge spicules from the Atlantic and Pacific sectors of the Southern Ocean and found higher silicic acid concentrations in the Pacific sector during the last glacial period. We propose that this increase results from changes in the stoichiometric uptake of silicic acid relative to nitrate and phosphate by diatoms, thus facilitating a redistribution of nutrients across the Pacific and Southern Oceans. Our results are consistent with the global Cd/Ca data set and support the silicic acid leakage hypothesis. 相似文献