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51.
Summary The ionic composition offour very productive and one unproductive fishpond has been investigated. The concentration of various ions is typical of carbonate waters except in two ponds for reasons of pollution. Calcium and bicarbonate are the major cation and anion while inspite of high productivity potassium is not very abundant. Because of the geographical position the area enjoys, the carbonate content seems to be important in productivity evaluation. For the same, its equivalent ratio to calcium and bicarbonate is very significant.  相似文献   
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BackgroundNanotechnology application has successfully reached numerous scientific breakthroughs including in radiotherapy. However, the clinical application of nanoparticles requires more diligent research primarily on the crucial parameters such as nanoparticle sizes. This study is aimed to investigate the influence of bismuth oxide nanorod (Bi2O3-NR) sizes on radiosensitization effects on MCF-7 and HeLa cell lines for megavoltage photon and electron beam radiotherapy.Materials and methodsMCF-7 and HeLa cells were treated with and without 0.5 μMol/L of Bi2O3-NR of varying sizes (60, 70, 80, and 90 nm). The samples, including the control groups, were exposed to different radiation doses (0–10 Gy), using photon (6 MV and 10 MV), and electron beam (6 MeV and 12 MeV) radiotherapy. Clonogenic assay was performed, and sensitization enhancement ratio (SER) was determined from linear quadratic based cell survival curves.ResultsThe results depicted that 60 nm Bi2O3-NR yields the most excellent SER followed by 70 nm Bi2O3-NR. Meanwhile, the 80 and 90 nm Bi2O3-NR showed an insignificant difference between treated and untreated cell groups. This study also found that MCF-7 was subjected to more cell death compared to HeLa.Conclusion60 nm Bi2O3-NR was the optimal Bi2O3-NR size to induce radiosensitization effects for megavoltage external beam radiotherapy. The SER in photon beam radiotherapy marked the highest compared to electron beam radiotherapy due to decreased primary radiation energy from multiple radiation interaction and higher Compton scattering.  相似文献   
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Killed avian influenza virus (AIV) vaccines have been used to control H5N1 infections in countries where the virus is endemic. Distinguishing vaccinated from naturally infected birds (DIVA) in such situations however, has become a major challenge. Recently, we introduced the recombinant ectodomain of the M2 protein (M2e) of H5N1 subtype as a novel tool for an ELISA based DIVA test. Despite being antigenic in natural infection the monomer form of the M2e used in ELISA had limited antigenicity and consequently poor diagnostic capability. To address this shortcoming, we evaluated the use of four tandem copies of M2e (tM2e) for increased efficiency of M2e antibody detection. The tM2e gene of H5N1 strain from Indonesia (A/Indonesia/CDC540/2006) was cloned into a pMAL- p4x expression vector and expressed in E.coli as a recombinant tM2e-MBP or M2e-MBP proteins. Both of these, M2e and tM2e antigens reacted with sera obtained from chickens following live H5N1 infection but not with sera from vaccinated birds. A significantly stronger M2e antibody reaction was observed with the tM2e compared to M2e antigen. Western blotting also supported the superiority of tM2e over M2e in detection of specific M2e antibodies against live H5N1 infection. Results from this study demonstrate that M2e tetramer is a better antigen than single M2e and could be more suitable for an ELISA based DIVA test.  相似文献   
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Retinitis pigmentosa (RP) refers to a genetically heterogeneous group of progressive neurodegenerative diseases that result in dysfunction and/or death of rod and cone photoreceptors in the retina. So far, 18 genes have been identified for autosomal-dominant (ad) RP. Here, we describe an adRP locus (RP42) at chromosome 7p15 through linkage analysis in a six-generation Scandinavian family and identify a disease-causing mutation, c.449G→A (p.S150N), in exon 6 of the KLHL7 gene. Mutation screening of KLHL7 in 502 retinopathy probands has revealed three different missense mutations in six independent families. KLHL7 is widely expressed, including expression in rod photoreceptors, and encodes a 75 kDa protein of the BTB-Kelch subfamily within the BTB superfamily. BTB-Kelch proteins have been implicated in ubiquitination through Cullin E3 ligases. Notably, all three putative disease-causing KLHL7 mutations are within a conserved BACK domain; homology modeling suggests that mutant amino acid side chains can potentially fill the cleft between two helices, thereby affecting the ubiquitination complexes. Mutations in an identical region of another BTB-Kelch protein, gigaxonin, have previously been associated with giant axonal neuropathy. Our studies suggest an additional role of the ubiquitin-proteasome protein-degradation pathway in maintaining neuronal health and in disease.  相似文献   
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