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761.
762.
This study aimed to identify the economic dimension of directing treated wastewater to the production of green fodder. To achieve its objectives, the study relied on economic equations, the method of using multiple criteria, and a scoring technique for prioritization. The study showed that green fodder is a crop that depletes water, as it consumes about 67.27% of the water used for agricultural purposes. In determining the priority of regions intending to use treated wastewater, the ranking put Riyadh region first, followed by the eastern region, the Qassim region, Hail, Makkah Al-Mukarramah, Tabuk, Asir, Al-Jawf, Jizan, Madinah, Najran, the northern borders, and Al-Baha, in this order. The area that can be cultivated with forage crops is estimated to be about 53.05 thousand hectares, with a production of 953.75 thousand tons. The cost of treating wastewater to make it usable amounts to 2126.22 million riyals, while the value of the benefits gained from its use is 2508.95 million riyals; thus, the Saudi agricultural economy achieves a net gain estimated at about 382.73 million riyals annually. Therefore, this study recommends the use of treated wastewater in the production of green fodder.  相似文献   
763.
The homology and diversification of genomic sequence encoding glucagon gene among native Egyptian buffalos, camel and sheep were tested using cattle as model. Oligodeoxynucleotide primers designed from the available GenBank data were used for PCR probing of the glucagon gene encoding sequence at different loci. The DNA oligomer probes were constructed to flank either the whole gene encoding sequence or different intra-gene encoding sequences. The PCR products were visualized using agarose gel electrophoresis. All species showed a same size band of prepro-glucagon when PCR was used to amplify the whole gene encoding sequence. In contrary, amplifications of different intra-gene loci failed to give the same results. The results indicated variable degrees of diversity among old world ruminating ungulates in the glucagon gene encoding sequence. Compared with other ruminants, the variation appears predominantly in camel. Surprisingly, the similarity in size between both amplification products of whole gene encoding sequence and the proposed size of glucagon cDNA definitely excludes the possibility of large intervening introns spanning the genomic sequence of the glucagon gene in these species. This indicates that, in contrast to other tested mammals, the glucagon gene includes an essentially full-length copy of glucagon mRNA. The study revealed a possible new aspect of glucagon gene evolution in order to correlate its corresponding protein function among different ruminant species.  相似文献   
764.
To investigate the adaptive capacity to a strong light environment when planted on degraded land, we examined photosynthetic properties in relation to photoinhibition for the sun-leaves of six tropical fruit tree species native to Malaysia before and after transplanting. The six species were: Bouea macrophylla (Bm), Callerya atropurpurea (Ca), Canarium pilosum (Cp), Cynometra cauliflora (Cc), Morinda citrifolia (Mc) and Syzygium sp. (Ssp), which produce edible fruit for endemic animals and birds, and are candidates for corridor plantations. Based on the measurements performed before transplanting, the degree of chronic photoinhibition indicated by the decrease in pre-dawn F v/F m was well associated with an accumulation of excessive excitation energy in PSII indicated by a decrease in photochemical quenching (qP). Among the species, Ca and Mc showed lower degrees of photoinhibition with higher qP. Higher electron transport rates (ETR) were observed with higher qP whereas there was no significant relationship between regulatory thermal dissipation (indicated by ) and qP. Energy dissipation via electron transport was suggested to be important in keeping qP high and preventing photoinhibition when compared among species. Cc and Bm showed lower ETR and higher susceptibility to photoinhibition before and after transplanting. New Cp and Mc leaves developed after transplanting showed increased area-based leaf nitrogen content (N area) and stomatal conductance (gs) compared with those before transplanting resulting in higher light-saturated net photosynthetic rates (A max) and ETR, and contributing to mitigate photoinhibition. In contrast to these species, Ca achieved high A max with a water conservative manner (indicated by its relatively lower gs), where the higher carboxylation efficiency accompanied with the higher N area allowed them to maintain relatively high A max and ETR at lower intercellular CO2 concentration.  相似文献   
765.
Objective Transplantation of renal grafts is an established treatment for renal failure in a variety of medical conditions. Polymorphisms in genes, coding for proteins involved in immune response, may influence immunological and non-immunological mechanisms that lead to allograft loss. Vitamin D receptor (VDR) agonist has been shown to reduce short and long term allograft rejection in animal model. There are functional polymorphisms in VDR gene. Materials and methods A total of 75 renal allograft recipients with at least 2 years follow-up were selected and genotyped for two polymorphisms in the VDR genes (FokI and BsmI) and the association of each genotype with renal allograft survival and acute rejection was evaluated. Results We are unable to find statistically significant association between any of the study polymorphisms and clinical outcomes. Conclusion We have found no evidence to suggest that either VDR FokI or BsmI polymorphism determines the incidence of acute rejection or graft survival after renal transplantation. A larger sample size is necessary to confirm these findings.  相似文献   
766.
Blunt and rotational head impacts due to vehicular collisions, falls and contact sports cause relative motion between the brain and skull. This increases the normal and shear stresses in the (skull/brain) interface region consisting of cerebrospinal fluid (CSF) and subarachnoid space (SAS) trabeculae. The relative motion between the brain and skull can explain many types of traumatic brain injuries (TBI) including acute subdural hematomas (ASDH) and subarachnoid hemorrhage (SAH) which is caused by the rupture of bridging veins that transverse from the deep brain tissue to the superficial meningeal coverings. The complicated geometry of the SAS trabeculae makes it impossible to model all the details of the region. Investigators have compromised this layer with solid elements, which may lead to inaccurate results. In this paper, the failure of the cerebral blood vessels due to the head impacts have been investigated. This is accomplished through a global/local modelling approach. Two global models, namely a global solid model (GSM) of the skull/brain and a global fluid model (GFM) of the SAS/CSF, were constructed and were validated. The global models were subjected to two sets of impact loads (head injury criterion, HIC = 740 and 1044). The relative displacements between the brain and skull were determined from GSM. The CSF equivalent fluid pressure due to the impact loads were determined by the GFM. To locally study the mechanism of the injury, the relative displacement between the brain and skull along with the equivalent fluid pressure were implemented into a new local solid model (LSM). The strains of the cerebral blood vessels were determined from LSM. These values were compared with their relevant experimental ultimate strain values. The results showed an agreement with the experimental values indicating that the second impact (HIC = 1044) was strong enough to lead to severe injury. The global/local approach provides a reliable tool to study the cerebral blood vessel ruptures leading to ASDH and/or SAH.  相似文献   
767.
Previously we have shown that DAB389IL-2, a recombinant fusion toxin targeting IL-2R bearing cells, suppressed disease in the rat experimental autoimmune encephalomyelitis (EAE) model of acute multiple sclerosis (MS). Our present study demonstrates that DAB389IL-2 can also effectively suppress acute (A)-EAE, relapsing (R)-EAE and chronic (C)-EAE in mouse demyelinating models. DAB389IL-2 significantly suppressed mitogenic proliferation of spleen cells while mutant fusion proteins DAglu53B389IL-2 and DAB389IL-28-10 did not. EAE was successfully suppressed when DAB389IL-2 was administered in various regimens between days 1 and 15 post immunization in all three models. CD4+IL-2R+ cells were reduced in the spleen but not in the lymph nodes of DAB389IL-2-treated mice during A-EAE while the number of CD8+ cells was unchanged. DAB389IL-2 also significantly reduced the number of CD4+, CD8+, CD25+, TCRγδ+ phenotype and CD11b+ macrophages/microglia within spinal cord lesions. These data strongly suggest that DAB389IL-2 specifically targeted myelin protein-activated CD4+ T cells and strengthens the argument for the use of DAB389IL-2 in treatment strategies for MS.  相似文献   
768.
769.
The relative vulnerability of spinal motion segments to different loading combinations remains unknown. The meta-analysis described here using the results of a validated L2-L3 nonlinear viscoelastic finite element model was designed to investigate the critical loading and its effect on the internal mechanics of the human lumbar spine. A Box-Behnken experimental design was used to design the magnitude of seven independent variables associated with loads, rotations and velocity of motion. Subsequently, an optimization method was used to find the primary and secondary variables that influence spine mechanical output related to facet forces, disc pressure, ligament forces, annulus matrix compressive/shear stresses and anulus fibers strain. The mechanical responses with respect to the two most-relevant variables were then regressed linearly using the response surface quadratic model. Axial force and sagittal rotation were identified as the most-relevant variables for mechanical responses. The procedure developed can be used to find the critical loading for finite element models with multi input variables. The derived meta-models can be used to predict the risk associated with various loading parameters and in setting safer load limits.  相似文献   
770.
There is increasing interest in the ability of diets rich in polyphenols to modulate age-related diseases and promote healthy ageing. We have conducted a pilot experiment with eight tomato varieties to correlate the total antioxidant capacity of the tomato variants with the specific constituent flavonoids present. A strong correlation was observed with the flavonol rhamnoglucoside rutin but not with other flavonoids, such as naringenin chalcone, or hydroxycinnamates, such as chlorogenic, which are also present in the tomato. To test the rigor of this correlation a second study was undertaken with a further 37 tomato varieties selected for low, medium and high rutin levels. We show that the flavonol rutin contributes to the greatest extent to the antioxidant capacity of tomatoes and suggest that this flavonoid may be a useful target for up-regulation in tomatoes in order to improve their antioxidant status.  相似文献   
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