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11.
Lobelia giberroa is a giant rosette plant growing in the afro-montane belt of the afro-alpine environment, a unique and little-studied ecosystem occupying the high mountains of eastern Africa. We analysed amplified fragment length polymorphisms (AFLPs) from 11 mountain systems in Ethiopia and Tropical East Africa to infer the phylogeographical history of the species. A total of 191 individuals were investigated from 25 populations. Principal coordinate analysis and population structure analyses revealed three major phylogeographical groups: the Ethiopian mountains and one group on each side of the Rift Valley in Tropical East Africa, respectively: Elgon-Cherangani and Kenya-Aberdare-Kilimanjaro-Meru. Analysis of Molecular Variance showed 55.7% variance among the three groups, suggesting an old divergence. Together with a clear geographical substructure within the main groups, this pattern indicates gradual expansion and supports the montane forest bridge hypothesis, stating that the area occupied by forest was larger and more continuous in previous interglacials and earlier in the present interglacial. Genetic diversity was lower in Ethiopia than in the other two main groups, possibly due to an ancient founder effect when Ethiopia was colonized from the south.  相似文献   
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The bioisosteric replacement of the indole core of CRTH2 antagonists using thienopyrroles was investigated, resulting in potent antagonists with good selectivity over DP1. Early ADME/PK assessment of this chemotype demonstrated bioavailability in mice.  相似文献   
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Microdomains such as rafts are considered as scaffolds for phosphatidylinositol (4,5) bisphosphate (PIP2) signaling, enabling PIP2 to selectively regulate different processes in the cell. Enrichment of PIP2 in microdomains was based on cholesterol-depletion and detergent-extraction studies. Here we show that two distinct phospholipase C-coupled receptors (those for neurokinin A and endothelin) share the same, homogeneously distributed PIP2 pool at the plasma membrane, even though the neurokinin A receptor is localized to microdomains and is cholesterol dependent in its PIP2 signaling whereas the endothelin receptor is not. Our experiments further indicate that detergent treatment causes PIP2 clustering and that cholesterol depletion interferes with basal, ligand-independent recycling of the neurokinin A receptor, thereby providing alternative explanations for the enrichment of PIP2 in detergent-insoluble membrane fractions and for the cholesterol dependency of PIP2 breakdown, respectively.  相似文献   
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An alternative to land spreading of manure is to grow crops of algae on the N and P present in the manure and convert manure N and P into algal biomass. The objective of this study was to evaluate the fertilizer value of dried algal biomass that had been grown using anaerobically digested dairy manure. Results from a flask study using two soils amended with algal biomass showed that 3% of total algal nitrogen (N) was present as plant available N at day 0. Approximately 33% of algal N was converted to plant available N within 21 days at 25 degrees C in both soils. Levels of Mehlich-3 extractable phosphorus (P) in the two soils rose with increasing levels of algal amendment but were also influenced by existing soil P levels. Results from plant growth experiments showed that 20-day old cucumber and corn seedlings grown in algae-amended potting mix contained 15-20% of applied N, 46-60% of available N, and 38-60% of the applied P. Seedlings grown in algae-amended potting mixes were equivalent to those grown with comparable levels of fertilizer amended potting mixes with respect to seedling dry weight and nutrient content. These results suggest that dried algal biomass produced from treatment of anaerobically digested dairy manure can substitute for commercial fertilizers used for potting systems.  相似文献   
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ABSTRACT: Back groundReference intervals (RIs) are ranges of upper and lower limits of a given analyte which are used for a laboratory test to determine whether a disease is present or absent or to know if the patient is at risk for future disease states. In Ethiopia, a country with highly diversified population groups and geographical sites, there are no established RIs to metabolic analytes including the liver function test (LFT) analytes for the pediatric population though it has been known that liver function assessment in this population is vital as a result of varied vulnerability to both endogenous and xenobiotic substances. METHODS: A cross sectional study was conducted in Tikur Anbessa Specialized Hospital (TASH) and Teklehaymanot Health Center (THC) from November 2010 to April 2011. 117 cord blood (from newborns) and venous blood samples (from infants) were collected and analyzed using HumaStar 300. All pre-analytical, analytical and post-analytical aspects were thoroughly controlled. A robust, CLSI/ IFCC recommended, method was used for the determination of upper and lower end points covering 95% of the reference values of each analyte with respective 90% CIs using MedCalc(R) software. RESULTS: Combined RIs for newborns and infants were established for albumin, AST, ALP, direct bilirubin and total bilirubin to be 3.88-5.82 g/dl, 16.1-55.4U/l, 130-831U/l, <0.41 mg/dl and <1.37 mg/dl respectively. But, separated RIs were indicated for ALT and GGT as 1.2-23.1U/l and 6.94-24.8U/l ALT; and 30.6-160.7U/L and 10--28.2U/l GGT for newborns and infants respectively. Some maternal and infantile factors were identified to affect the values of analytes. CONCLUSION: Almost all analytes were different from previously reported values for other target population of similar age group, kit insert values and adult values. So, interpretation of values of these analytes in newborns and infants of Ethiopian population sounds better to be performed by using such RIs taking the effect of some maternal and infantile factors in to account.  相似文献   
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Drought is a major constraint in sorghum production worldwide. Drought-stress in sorghum has been characterized at both pre-flowering and post-flowering stages resulting in a drastic reduction in grain yield. In the case of post-flowering drought stress, lodging further aggravates the problem resulting in total loss of crop yield in mechanized agriculture. The present study was conducted to identify quantitative trait loci (QTLs) controlling post-flowering drought tolerance (stay green), pre-flowering drought tolerance and lodging tolerance in sorghum using an F7 recombinant inbred line (RIL) population derived from the cross SC56×Tx7000. The RIL lines, along with parents, were evaluated for the above traits in multiple environments. With the help of a restriction fragment length polymorphism (RFLP) map, which spans 1,355 cM and consists of 144 loci, nine QTLs, located over seven linkage groups were detected for stay green in several environments using the method of composite interval mapping. Comparison of the QTL locations with the published results indicated that three QTLs located on linkage groups A, G and J were consistent. This is considered significant since the stay green line SC56 used in our investigation is from a different source compared to B35 that was used in all the earlier investigations. Comparative mapping has shown that two stay green QTLs identified in this study corresponded to stay green QTL regions in maize. These genomic regions were also reported to be congruent with other drought-related agronomic and physiological traits in maize and rice, suggesting that these syntenic regions might be hosting a cluster of genes with pleiotropic effects implicated in several drought tolerance mechanisms in these grass species. In addition, three and four major QTLs responsible for lodging tolerance and pre-flowering drought tolerance, respectively, were detected. This investigation clearly revealed the important and consistent stay green QTLs in a different stay green source that can logically be targeted for positional cloning. The identification of QTLs and markers for pre-flowering drought tolerance and lodging tolerance will help plant breeders in manipulating and pyramiding those traits along with stay green to improve drought tolerance in sorghum. Received: 2 June 2000 / Accepted: 15 November 2000  相似文献   
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ObjectiveTo identify the incidence of and predictors for tuberculosis in children living with HIV in Northern Ethiopia.DesignObservational, retrospective follow-up study.MethodsA total of 645 HIV-infected children were observed between September 2009 and September 2014. Cox regression analysis was used to identify predictors for developing TB.ResultsThe incidence rate of tuberculosis was 4.2 per 100 child-years. Incidence of tuberculosis was higher for subjects who were not on cotrimoxazole preventive therapy, were not on isoniazid preventive therapy, had delayed motor development, had a CD4 cell count below the threshold, had hemoglobin level less than 10 mg/dl and were assessed as World Health Organization (WHO) clinical stage III or IV.ConclusionIncidence of TB in children living with HIV was high. This study reaffirmed that isoniazid preventive therapy is one of the best strategy to reduce incidence of TB in children living with HIV. All children living with HIV should be screened for TB but for children with delayed motor development, advanced WHO clinical stage, anemia or immune suppression, intensified screening is highly recommended.  相似文献   
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This study investigated the concurrent accumulation of eight heavy metals by two floating aquatic macrophytes (Lemna minor and Azolla filiculoides) cultivated in ambient media and blended wastewaters in the semiarid regions of Ethiopia. Both species accumulated heavy metals in varying degrees with a significant concentration gradient within the immediate water media. Highest bioconcentration factor (BCF) was determined for Mn and Fe in both plants. Results revealed that L. minor was high phytoaccumulator for Fe, Mn, Zn, and Co but moderate for Cd, Cu, Ni, and Cr. On the other hand, A. filiculoides was a high accumulator for Fe, Mn, Zn, and Cu, but its potency was moderate for Co, Cr, and Ni, but lower for Cd. Both species exhibited significant difference in accumulating Co, Zn, and Mn (p < 0.05). In general, the BCFs for both plants were comparable within the same treatment. In this study, stronger associations between the heavy metal concentrations in the plant tissues and in the grown water media were observed for A. filiculoides.  相似文献   
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