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The dried plant material of medicinally important Anthemis deserti Boiss. (family: Asteraceae) especially when it remains in the powdered form often look similar to Anthemis melampodina Del.; and therefore, difficult to distinguish, finally lead to chances of adulteration. The adulteration in medicinal plants effects on the efficacy of the drugs. The molecular authentication of herbal plant materials such as based on the internal transcribed spacer 2 (ITS2) sequences of nuclear ribosomal DNA (nrDNA) is considered as more reliable method compared to other the biochemical or histological methods. The present study aims to molecular authentication ofA. deserti based on molecular phylogenetic analyses of ITS2 gene sequence of nrDNA region. The ITS2 region of nrDNA of A. deserti were sequenced, and the molecular phylogenetic analyses were performed together with the GenBank sequences. The Maximum Parsimony tree revealed the close relationships of A. deserti with A. melampodina; however, the Neighbor-Joining and Maximum Likelihood tree clearly revealed that A. deserti is distinct from A. melampodina, which is also supported by the differences in nucleotides at five diffident positions (i.e. 22, 28, 87, 175 and 198) in the DNA sequence alignment.  相似文献   
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A viable option for increasing nitrogen (N) use efficiency and mitigation of negative impacts of N on the environment is to capitalize on multi-element interactions through implementation of nutrient management programs that provide balanced nutrition. Numerous studies have demonstrated the immediate efficacy of this approach in the developing regions like China and India as well as developed countries in North America. Based on 241 site-years of experiments in these countries, the first-year N recovery efficiency (RE) for the conventional or check treatments averaged 21% while the balanced treatments averaged 54% RE, for an average increase of 33% in RE due to balanced nutrition. Effective policies to promote adoption are most likely those that enable site-specific approaches to nutrient management decisions rather than sweeping, nation-wide incentives supporting one nutrient over another. Local farmers, advisers and officials need to be empowered with tools and information to help them define necessary changes in practices to create more balanced nutrient management.  相似文献   
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Marine bacteria from the hull of a ship in the form of biofilms or microfouling were isolated, cultured, and identified by phylogenetic analysis using 16S rDNA sequences. With an average length of 946 bp, all the 16 sequences were classified using the Ribosomal database project (RDP) and were submitted to the National Center for Biotechnology Information. Phylogenetic analysis using 16S rDNA sequences indicated that the 16 strains belonged to the Firmicutes (IK-MB6 Exiguobacterium aurantiacum, IK-MB7 Exiguobacterium arabatum, IK-MB8 Exiguobacterium arabatum, IK-MB9 Jeotgalibacillus alimentarius, IK-MB10 Bacillus megaterium, IK-MB11 Bacillus pumilus, IK-MB12 Bacillus pumilus, IK-MB13 Bacillus pumilus, IK-MB14 Bacillus megaterium), High GC, Gram-positive bacteria (IK-MB2 Micrococcus luteus, IK-MB5 Micrococcus luteus, IK-MB16 Arthrobacter mysorens), G-Proteobacteria (IK-MB3 Halomonas aquamarina, IK-MB15 Halotalea alkalilenta), CFB group bacteria (IK-MB1 Myroides odoratimimus), and Enterobacteria (IK-MB4 Proteus mirabilis). Among the 16 strains, representatives of the Firmicutes were dominant (56.25%) compared to the high GC, Gram-positive bacteria (18.75%), G-Proteobacteria (12.5%), CFB group bacteria (6.25%), and Enterobacteria (6.25%). Analysis revealed that majority of marine species found in marine biofilm are of anthropogenic origin.  相似文献   
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The internal transcribed spacer (ITS) region of nuclear ribosomal DNA, trnL and trnL-F genes of Cardamine glechomifolia Levl. (family Brassicaceae) were sequenced and analyzed with the sequence of related Cardamine species retrieved from NCBI GenBank to detect pattern of evolutionary differentiation. All trees resulting from combined sequence analyses data of ITS, trnL and trnL-F gene resolve that C. glechomifolia – an endemic species to South Korea clade with Cardamine microzyga (100% bootstrap support). The evolutionary history was inferred using the Maximum Parsimony method. The consistency index is (0.588235), the retention index is (0.687500), and the composite index is 0.519622 (0.404412) for all sites and parsimony-informative sites (in parentheses). The result of the analysis using Maximum Parsimony was found congruence with Maximum Likelihood method and in Baseyan analysis.  相似文献   
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Salinity tolerance in some mangrove species from Pakistan   总被引:1,自引:0,他引:1  
Growth, ionic and water relations of three mangrove species viz. Avicennia marina, Ceriops tagal and Rhizophora mucronata werestudied in different seawater concentrations (0, 25, 50, 75 and 100%).All mangrove species showed optimal growth at 50% seawater. Relativelymore biomass was accumulated by R. mucronata while C. tagalhad the tallest individuals. Tissue water potential became more negativewith the increase in salinity and stomatal conductance was decreased in allplants. Higher stomatal conductance was noted in R. mucronata,followed by A. marina and C. tagal. Sodium and chloride ionsincreased with the increase in salinity and this accumulation was muchhigher in A. marina.  相似文献   
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A 25-year-old previously asymptomatic pregnant woman at 36 weeks'' gestation was noticed to have repetitive monomorphic ventricular tachycardia. A dilated left ventricle with moderately reduced systolic function was found on echocardiographic examination. This is a very rare presentation of peripartum cardiomyopathy (PPCMP) presenting with repetitive monomorphic ventricular tachycardia.  相似文献   
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The diversity of natural phytochemicals represents an unlimited source for discovery and development of new drugs. Ochradenus arabicus, (family: Resedaceae) a notable medicinal plant displays a high content of flavonoid glycosides. This study investigates a possible preventative role of zinc nanoparticles biosynthesized by O. arabicus leaf extracts (OAZnO NPs) in limiting genotoxicity and cytotoxicity caused by indole acetic acid (IAA) in laboratory mice. ZnO NPs were synthesized using O. arabicus leaf extracts and characterized with UV–visible spectroscopy, scanning electron microscopy (SEM) and X-Ray diffraction (XRD). The mice were randomly distributed into the following six groups: control, OAZnO NPs treated (10 mg/kg BW), IAA treated (50 mg/kg BW); simultaneous treatment, pre-treatment, and post-treatment. Reactive oxygen species (ROS), DNA damage, chromosome aberration, and apoptosis were analyzed as toxicity endpoints. IAA exposure significantly induced production of ROS, DNA damage, apoptosis, chromosome aberrations, and micronuclei. Pre-, post-, and simultaneous treatment with OAZnO NPs ameliorated the damage caused by IAA exposure. Exposure to OAZnO NPs alone caused no toxicity for any endpoint based on comparison to controls. This study demonstrated that IAA-induced cytotoxic damage in mice could be ameliorated by treatment with OAZnO NPs. These findings require additional verification in mechanistic and in vitro studies.  相似文献   
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