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71.
ABSTRACT Numerous whitefly-transmitted viral diseases of tomato have emerged in countries around the Nile and Mediterranean Basins the last 20 years. These diseases are caused by monopartite geminiviruses (family Gemini viridae) belonging to the genus Begomovirus that probably resulted from numerous recombination events. The molecular biodiversity of these viruses was investigated to better appreciate the role and importance of recombination and to better clarify the phylogenetic relationships and classification of these viruses. The analysis partitioned the tomato-infecting begomoviruses from this region into two major clades, Tomato yellow leaf curl virus and Tomato yellow leaf curl Sardinia virus. Phylogenetic and pairwise analyses together with an evaluation for gene conversion were performed from which taxonomic classification and virus biodiversity conclusions were drawn. Six recombination hotspots and three homogeneous zones within the genome were identified among the tomatoinfecting isolates and species examined here, suggesting that the recombination events identified were not random occurrences. 相似文献
72.
73.
H. Abu Damir S. J. Kenyon Amna E. Khalaf Alla O. F. Idris 《Tropical animal health and production》1984,16(4):209-212
Summary Sera of 740 camels of both sexes from three regions of Sudan were tested for antibodies toBrucella abortus. The overall incidence of antibodies was 4.9%. The highest positive number of samples (7.5%) was from the Eastern Region followed by Darfur Region (3.1%) and the Central Region (2.0%).Brucella antibodies were as frequent in males (5.6%) as females (4.5%).
Anticuerpos De Brucela En Camellos Sudadeses
Resumen Se analizaron 740 sueros de camellos de ambos sexos, provenientes de tres regiones de Sudán, para detectar anticuerpos deBrucella abortus. La incidencia general de anticuerpos fué de 4.9%. El más alto número de pruebas positivas (7.5%) correspondió a la Regió Oriental, seguida de la Región de Darfur (3.1%) y la Región Central (2.0%). Los anticuerpos fueron tan frecuentes en machos (4.5%), como en hembras (5.6%).
Anticorps Brucelliques Chez Les Chameaux Du Soudan
Résumé Les anticorps anti-brucelliques (Brucella abortus) ont été recherchés dans les sérums de 740 chameaux des deux sexes originaires de trois régions du Soudan. L'incidence globale des anticorps étant de 4,9 p. 100. Le nombre d'échantillons positifs le plus élevé (7,5 p. 100) provenait de la région Est suivi par le Darfour (3,1 p. 100) et le Centre (2,0 p. 100). Les anticorps brucelliques étaient aussi fréquents chez les mâles (4,5 p. 100) que chez les femelles (5,6 p. 100).相似文献
74.
Khoo HE Ismail A Mohd-Esa N Idris S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):170-175
This study was conducted to evaluate the total carotene content (TCC) and beta carotene (BC) in the selected underutilized tropical fruits. TCC of underutilized fruits estimated by spectrophotometric method was in the range of 1.4-19.8 mg/100 g edible portion. The TCC of these fruits decreased in the order: Jentik-jentik > Durian Nyekak 2 > Durian Nyekak 1 > Cerapu 2 > Cerapu 1 > Tampoi Kuning > Bacang 1 > Kuini > Jambu Mawar > Bacang 2 > Durian Daun > Bacang 3 > Tampoi Putih > Jambu Susu. BC contents estimated by HPLC method were highest in Jentik-jentik, followed by Cerapu 2, Durian Nyekak 2, Tampoi Kuning, Durian Nyekak 1, and Cerapu 1, which had a range of 68-92% of BC in TCC. These underutilized fruits have an acceptable amount of carotenoids that are potential antioxidant fruits. 相似文献
75.
A cytotoxic triterpenoid saponin was isolated from the under-ground parts of Gypsophila pilulifera Boiss.& Heldr. (Caryophyllaceae) naturally grow in the southwestern region of the Turkey. The structures of saponin was elucidated as 3-O-β-D-galactopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucuronopyranosyl quillaic acid 28-O-β-D-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→4]-α-l-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl ester on the basis of extensive spectral analysis and chemical evidence. The separated triterpenoid saponin was isolated from Gypsophila pilulifera for the first time. The saponin compound displayed significant cytotoxicity against A549 cell line with IC(50) values >16μM. 相似文献
76.
Naoki Yamanaka Masrom Hasran Dong He Xu Hiroshi Tsunematsu Salma Idris Tomohiro Ban 《Genetic Resources and Crop Evolution》2006,53(5):949-954
We used AFLP analysis to explore the genetic relationship and diversity between and within 4 Mangifera species. We analyzed 35 accessions comprising 8 cultivars and 3 landraces of M. indica L., 11 landraces of M. odorata Griff., 7 landraces of M. foetida Lour., and 6 landraces of M. caesia Jack. Using 8 primer combinations produced a total of 518 bands, 499 (96.3%) of which were polymorphic among the 35 accessions.
Clustering analysis showed that all 35 accessions were basically classified into 4 groups corresponding to the 4 Mangifera species. Our results indicate that the genetic relationship of these 4 Mangifera species based on AFLP analysis is in good agreement with their classification by classic methods. In addition, it was clearly
revealed the genetic diversity between and within 4 Mangifera species. The findings obtained in this study are useful for the breeding in Mangifera species. 相似文献
77.
A study was conducted in South Kordofan, Sudan to determine the effect of tapping, tapping tools and date of tapping on the gum yield of Acacia polyacantha. A two-factor experiment was conducted for two seasons in 2008-2009. One location was used for two seasons and two locations for one season. The first factor (4 levels) was the tools of tapping: Makmak, Farrar, and Sonki, and the control which was not tapped. The second factor (2 levels) was the date of tapping that comprises mid October and mid November. These treatments were arranged in Randomaized Complete Block Design and replicated three times. Gum yield (g/tree and g/ picking) was recorded for five pickings. Economic analysis was done using the partial budget technique. The results showed highly significant (p < 0.01) differences on gum yield (g/picking and g/tree). The results indicated that the process of tapping increases gum production by 88.4% and 79.8% compared with un-tapped trees, respectively. The date of tapping has no significant effect on gum yield (g/tree and g/picking) of A. polyacantha. Tapping of the tree with Makmak in mid- November was found to be economically beneficial compared to using the other tools and the control. These results could identify a new source of income for the poor farmers in South Kordofan mainly because of the wild occurrence of Kakamut as a potential gum producing tree species grown naturally in the area. 相似文献
78.
Ninety hybrid (mainly Large White × Landrace) pigs from 2 experimental replicates were used to study the potential use of computed tomography (CT) as a nondestructive technology for estimating the chemical body composition of growing pigs. Body tissue components (lean, fat, and bone) of 6 live pigs from each sex (boars, gilts, and barrows) were assessed by CT imaging before slaughter at approximately 30, 60, 90, 120, and 150 kg of BW. After slaughter, the empty body components were ground and frozen until analyzed for protein, lipid, ash, and moisture content. Several growth functions were evaluated and the allometric function (Y = aBW(b)), which was evaluated as log(10)chemical component weight = b(0) + b(1)log(10)BW, provided the best fit to the data. For each sex, the allometric coefficient (b(1)) for protein (0.92 to 0.99) was close to but less than 1; for ash (1.03 to 1.12), it was close to but greater than 1; for moisture (0.82 to 0.86), it was less than 1, and for lipid (1.61 to 1.71), it was greater than 1. Deposition rates (change in component weight per unit change in BW) for each chemical component were predicted using derivatives of the function. The mean deposition rates for protein and lipid were 0.141 and 0.286 kg/kg of BW gain, respectively. The deposition rate for protein was generally stable across different BW, whereas that for lipid increased as BW increased. In addition, linear, quadratic, exponential, and logistic functions were fitted to the data to study the relationship between the CT data and chemical components. The linear function was assessed to be the best equation, based on the Bayesian information criterion. The prediction equation for protein (kg) = -1.64 + 0.28 × CT lean (kg), and for lipid (kg) = -0.69 + 1.09 × CT fat (kg), had R(2) values of 0.924 and 0.987, respectively. Sex had no effect (P > 0.05) on the prediction of protein and lipid. The effect of BW was not significant (P > 0.05) for the prediction of lipid, but it was significant (P > 0 0.05) for the prediction of protein. However, the addition of BW to the base prediction equation for protein resulted in an increase of only 0.013 in the R(2) value. It was concluded from this study that CT scanning has great potential as a nondestructive technology for estimating the physical and chemical body composition of pigs. Additional research is required to validate the utility and accuracy of the prediction equations. 相似文献
79.
Maikai BV Umoh JU Kwaga JK Lawal IA Maikai VA Cama V Xiao L 《Veterinary parasitology》2011,178(3-4):241-245
Despite numerous molecular epidemiologic studies of cryptosporidiosis in dairy cattle in industrialized countries, there are very few studies on the diversity and public health significance of Cryptosporidium species in native cattle in developing countries. In this study, a polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the small-subunit (SSU) rRNA gene was used to detect and identify Cryptosporidium spp. in 194 fecal specimens from 2 to 365 days old calves in 20 White Fulani and Sokoto Gudali herds in Nigeria. Thirty one (16.0%) of the specimens were positive for Cryptosporidium. Restriction digestion of the PCR products showed the presence of Cryptosporidium bovis (7.2%), Cryptosporidium ryanae (4.1%), Cryptosporidium andersoni (2.5%), and concurrent occurrence of C. bovis and C. ryanae (1.5%), and C. bovis and C. andersoni (0.5%). There were no significant differences (p>0.05) in Cryptosporidium infection rates by sex, herd location, management system, breed of calves, or fecal consistency. However, calves 180 days or younger had a higher infection rate of Cryptosporidium than older calves (p=0.034). Likewise, younger calves also had higher occurrence of C. bovis and C. ryanae (p=0.022). The absence of zoonotic Cryptosporidium parvum in the calves studied suggests that native breeds of cattle may not be important in the transmission of human cryptosporidiosis in Kaduna State, Nigeria. 相似文献
80.
Osei-Amponsah R Kayang BB Naazie A Arthur PF Barchia IM 《Tropical animal health and production》2011,43(6):1195-1201
The Richards growth model was fitted to body weight-age data of local and SASSO T44 chickens to describe their growth performance.
Males had higher (P < 0.05) asymptotic mature weights than females. Within the local chicken population, birds from the savannah zone had higher
(P < 0.05) asymptotic mature weights compared to forest chicken which ironically had higher body weights at hatch. Male local
chicken had lower maturing rates compared to the females. Female local chicken were superior to SASSO T44 females in terms
of maturing rate. On the average, local chickens took relatively longer time (78.4–83.3 days) to reach the point of inflection
than the SASSO T44 population (74.2–79.8 days). However, there were no significant differences (P > 0.05) in the age at inflection among local chicken populations. The shape parameter for SASSO T44 chicken (0.053–0.370)
and maturation rate for local chicken (0.177–0.198) were the most critical parameters. Scaling the body weights into degree
of maturity highlighted the degree to which genotypes matured over time. Female chickens had the highest (P < 0.05) degree of maturity at all ages. The local chicken populations were also metabolically older than SASSO T44 chickens.
Results of this study provide an opportunity to develop breeding strategies for local chicken by modifying either management
practices or their genetic makeup to positively affect their growth and productivity. 相似文献