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61.
Scalp hair samples of traffic control personnel (n = 71, ages between 25 to 45 years) were analyzed for 11 selected metals by using an Inductively Coupled Argon Plasma Atomic Emission (ICP-AE) technique using nitric acid–perchloric acid based wet digestion method. The observed order of mean concentrations (μ g/g, dry weight) of the metals, in washed hair samples, was: Ca > Mg > Zn > Fe > Pb > Cu > Ni > Mn > Cr > Cd > Co, with corresponding metal levels at 1042.2, 182.4, 169.7, 13.6, 12.4, 11.1, 2.7, 1.9, 1.9, 0.8, and 0.7 μ g/g, respectively. Most of the unwashed samples exhibited 10–15% higher metal levels compared with those in washed samples. A positive metal-to-metal correlation (p < 0.01) was observed for the metal pairs: Ca-Mg (r = 0.737), Pb-Cr (r = 0.441), and Cu-Zn (0.385). Principal Component Analysis (PCA) extracted 6 factors as metals origin using varimax normalized rotation commutatively representing more than 76% of the total variance. Cluster Analysis (CA) showed five strong clusters of selected metals in the hair of the subjects: Age-Exposure, Ca-Mg, Cd-Fe-Mn, Pb-Cr, and Cu-Zn. The results of the current study were compared with those for two other occupationally exposed groups, metal arc welders and autodrivers, using published literature values. The traffic controllers in our study generally, with the exception of Cu, exhibited lower levels of metals in hair samples than did autodrivers and arc welders.  相似文献   
62.
Two new pentacyclic triterpenes eleganene-A (1) and eleganene-B (2), along with four known pentacyclic triterpenes betulin (3), ursolic acid (4), erythrodiol (5) and corosolic acid (6) were isolated from the aerial parts of Myricaria elegans. These compounds exhibited significant antibacterial activity. The structure of compounds 1 and 2 were deduced on the basis of their spectral analysis.  相似文献   
63.
Recent studies have established the controlling influence of rhizospheric biota, especially arbuscular mycorrhizal fungi (AMF), on colonization and spread of some alien plants in their introduced range. But how AMF from different geographical sources influence traits that contribute to invasiveness, particularly in presence of neighbouring plants of other species, has been rarely investigated. Thus, we compared the influence of some local (Kashmir Himalayan isolates) and non-local (isolates from Rajasthan, India) AMF isolates of Glomus moseae, G. fasciculatum and Gigaspora margarita on vegetative and reproductive attributes of Mayweed Chamomile (Anthemis cotula L.), a highly invasive species in the Kashmir Himalaya, India. We also examined whether or not the neighbouring plant species, namely Daucus carota L. (Apiaceae) alters the mutualistic interaction between the AMF and A. cotula. Pot experiments revealed greater positive impact of the local than the non-local AMF on vegetative as well as reproductive attributes of A. cotula. Experimental field studies showed that the incidence of highly prevalent Arum-type mycorrhizal colonization in natural populations of A. cotula was reduced in presence of D. carota. Besides, the local AMF significantly promoted growth of A. cotula more than D. carota under mixed-culture conditions. These results suggest that the facilitation of some alien plant invasions by AMF needs to be considered together with plant–plant interactions and invasion-induced changes in the soil microbial community.  相似文献   
64.
The ParB family partitioning protein, KorB, of plasmid RK2 is central to a regulatory network coordinating replication, maintenance and transfer genes. Previous immunofluorescence microscopy indicated that the majority of KorB is localized in plasmid foci. The 12 identified KorB binding sites on RK2 are differentiated by: position relative to promoters; binding strength; and cooperativity with other repressors and so the distribution of KorB may be sequestered around a sub-set of sites. However, chromatin immunoprecipitation analysis showed that while RK2 DNA molecules appear to sequester KorB to create a higher local concentration, cooperativity between DNA binding proteins does not result in major differences in binding site occupancy. Thus under steady state conditions all operators are close to fully occupied and this correlates with gene expression on the plasmid being highly repressed.  相似文献   
65.
Glaucoma is a very common disorder of the eye wherein the disturbance of the structural or functional integrity of the optic nerve causes characteristic atrophic changes in the optic nerve, which may lead to specific visual field defects over time. Primary open angle glaucoma (POAG) is most frequent among the three principle glaucoma subtypes. With well-established role of genes like Myocilin (MYOC), Optineurin (OPTN) and WD repeat Domain 36, (WDR36), at least 29 genetic loci have been found till date to be linked to POAG. Moreover, association studies have found 66 loci with 76 genes associated to POAG till date with conflicting results. This particular study is to summarize the current knowledge regarding the change in glaucoma prevalence worldwide and in India from 1993 onwards and compiles all the studied genes that are involved in POAG pathogenesis in Indian population.  相似文献   
66.
The mechanism of ATP hydrolysis by plasma membrane H(+)-ATPase from Candida albicans has been investigated by following the kinetics of H(+) liberation/absorption and the UV difference spectrum in a stopped flow spectrophotometer. A distinct pre-steady state phase of ATP hydrolysis could be defined. While the rapid mixing of P(i) and ATPase produced no transient pH changes, the mixing of ADP leads to the release of 1 H(+) per molecule of ATPase. Rapid mixing of ATP with ATPase releases about 2 H(+) per molecule of ATPase, of which around 1.3 H(+) are reabsorbed. The magnitudes of both H(+) release and absorption were found to be independent of ATP concentration. The rate of H(+) release (k(f)) shows ATP dependence while the rate of H(+) absorption is independent of ATP concentration. The rate of H(+) liberation with ADP, on a concentration basis, was far less as compared with ATP, indicating a low affinity of the ATPase for ADP. No change in the difference spectrum was observed with ADP. The stoichiometry of ATP binding to PM-ATPase was found to be unity from UV-difference spectrum studies. The k(f) values for H(+) release and for the appearance of a difference spectrum following the addition of ATP were found to be similar beyond a 1:1 ratio of ATP:ATPase. The results obtained lead us to propose a 4-step kinetic scheme for the mechanism of ATP hydrolysis.  相似文献   
67.
The development of drought tolerant wheat cultivars has been slow due to lack of understanding the diagnostic physiological parameters associated with improved productivity under water stress. We evaluated responses to PEG induced osmotic stress under hydroponics in D-genome synthetic derived and bread wheat germplasm with the main aim to unravel and identify some promising attributes having role in stress tolerances. Genotypes used in this study differed in their morpho-physiological and biochemical attributes. Tolerant genotypes exhibited the ability to ameliorate harmful effects of PEG induced osmotic stress through better osmotic adjustment achieved through substantial relative water content (RWC), lowered osmotic potential, relatively stable root length having maximum water extraction capacity, significant increase in osmoprotectant concentration and relatively enhanced antioxidant activities. The results clearly revealed the importance of synthetic derivatives over check cultivars and conventional wheats in terms of osmotic stress responses. Interestingly, synthetic-derived advanced lines with Aegilops tauschii in its parentage including AWL-02, AWL-04 and AWL-07 proved superior over the best rainfed check cultivar (Wa-01). It was concluded that synthetic-derived wheats has great potential to improve a range of stress adaptive traits. It could, therefore, be recommended to be a useful strategy for allowing modern bread wheat to become adapted to a wider range of environments in future climate change scenarios.  相似文献   
68.
Certain strains of Bacillus amyloliquefaciens can colonize plants and improve growth and stress management. In order to study these effects, bacterial growth dynamics on plants and in the rhizosphere are of interest calling for specific analytical tools. For that purpose, quantitative real-time PCR (qPCR) assays were developed in order to differentiate among three closely related B. amyloliquefaciens subsp. plantarum strains (UCMB5033, UCMB5036, UCMB5113) and to determine their levels with high accuracy. Oligonucleotide primers were designed for strain unique gene sequences and used for SYBR green based qPCR analysis. Standard curves covered a wide linear range (106) of DNA amounts with the lowest detection level at 50 fg. Post-reaction melting curve analysis showed only a single product. Accurate threshold cycles were obtained, even in the presence of high excess of related Bacillus strains and total bacterial DNA from soil. Analysis of Bacillus colonisation after seed treatment of two oilseed rape cultivars (Oase and Ritz) grown on agar support showed a time dependent effect but that the bacteria mostly were found on root tissues and little on green tissues. The colonisation on plants grown in soil varied among the Bacillus strains where Oase seemed to house more bacteria than Ritz. Applied as a mixture, all three Bacillus strains co-existed on the roots of plants grown in soil. The qPCR assay in combination with other techniques will be a powerful tool to study plant interactions of these B. amyloliquefaciens biocontrol agents to further understand the requirements for successful interactions and improvement of plant properties.  相似文献   
69.
The X-STRs are important tools in forensic application, particularly in complex cases of kinship testing. In deficiency paternity testing when alleged father cannot be typed, investigation of X-STR markers yields the desired information. Blood samples were collected from unrelated individual (118 females and 94 males) and 84 trios families (father, mother and daughter). DNA extraction from whole blood was performed with Phenol chloroform method. Five X-linked STR markers DXS6800, DXS7133, DXS6797, DXS981 and GATA165B12 were selected. The amplicons were analyzed through ABI 3100 Genetic Analyzer. Pentaplex PCR system was developed for multilocus amplification at the same time. For each locus 4–9 alleles were noted. Altogether, 32 alleles were observed from five markers. Eighty-four trios families were analysed to check the mutation rate and no mutation was observed. Stutter peaks were observed maximum at locus DXS6797 (12.44%) while the minimum at locus DXS7133 (4.5%). For sensitivity study, amplification of X chromosomal short tandem repeats loci was successfully performed using 0.15 ng quantity of DNA as template. In conclusion; this pentaplex represents a convenient method to study X chromosome markers. It works with reasonable amounts of DNA and is suitable for paternity cases.  相似文献   
70.
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