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181.
Soils contaminated simultaneously with polycyclic aromatic hydrocarbons (PAHs) and heavy metals pose major threat to human health and environment by getting released from soil into water environment. The purpose of this study was to evaluate simultaneous desorption and desorption kinetics of PAHs (phenanthrene and anthracene) and heavy metals (lead, nickel, and zinc) from artificially contaminated kaolinite soils with different organic matter content. Batch desorption tests were conducted using single and combined enhancing agents containing Triton X-100 and Tween 80 as non-ionic surfactants, Ethylenediaminetetraacetic acid (EDTA) as a chelating agent, and citric acid as an organic acid. The solution with the highest removal efficiency was the combined solution of Triton X-100 (10% w/w) + EDTA (0.01 M). Removal levels around 92, 46, 92, 95, and 96% were obtained for phenanthrene, anthracene, lead, nickel, and zinc, respectively, by using this combination. Batch desorption kinetics experiments were performed using the mentioned combination. During the first 24 h, desorption kinetics were rapid, followed by a plateau until the end. The data obtained from desorption kinetics experiments were fitted with four kinetics models: pseudo-second-order equation, empirical power function, elovich, and parabolic diffusion. The correlation coefficient of the pseudo-second-order equation was higher than that of other functions. Moreover, batch experiments have showed inverse correlations between removal efficiency and organic matter content of soil.  相似文献   
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Probiotics and Antimicrobial Proteins - In this study, yellowfin tuna (Thunnus albacores) viscera were hydrolyzed with protamex to obtain hydrolysate that is separated by a membrane ultrafiltration...  相似文献   
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We applied real-time broad-range polymerase chain reaction (PCR) to detect bacteraemia in blood from febrile patients. Interpretation of amplification results in relation to clinical data and blood culture outcome was complex, although the reproducibility of the PCR results was good. Sequencing analysis of the PCR products revealed the presence of Burkholderia species DNA while no Burkholderia species grew in culture. The source of this contamination was shown to be the commercial DNA isolation kit used in the automated MagNA Pure Isolation Robot. A high degree of suspicion is required when uncommon or unexpected pathogens are diagnosed by molecular methods as clinical consequences can be serious.  相似文献   
186.
Idiopathic hirsutism is defined as the occurrence of excessive male pattern hair growth in women who have a normal ovulatory menstrual cycle and normal levels of serum androgens. It may be a disorder of peripheral androgen metabolism. In this study we evaluated the clinical response of idiopathic hirsutism to topical Fennel extract. Fennel, Foeniculum vulgare, is a plant, which has been used as an estrogenic agent. The ethanolic extract of Fennel was obtained by using a soxhlete apparatus. In a double blind study, 38 patients were treated with creams containing 1%, 2% of Fennel extract and placebo. Hair diameter was measured and rate of growth was considered. The efficacy of treatment with the cream containing 2% Fennel is better than the cream containing 1% Fennel and these two were more potent than placebo. The mean values of hair diameter reduction was 7.8%, 18.3% and -0.5% for patients receiving the creams containing 1%, 2% and 0% (placebo) respectively.  相似文献   
187.

Since global warming affects wheat cropping systems, more has yet to be indicated on the parameters, which control terminal heat tolerance, and severely influence wheat (Triticum aestivum L.) productivity. Identification of tolerant wheat genotypes by heat tolerance-linked molecular markers is a rapid and cost-effective screening tool in plant breeding. Accordingly, in a four-year field experiment (2015–2019), 44 wheat genotypes were selected out of 100 genotypes, and were examined in timely and late planting (mid-January resulting in heat stress). Stress decreased yield components, including 1000-kernel weight (TKW), grains per spike, and plants per square meter, and the physiological traits, including days to heading and days to maturity, grain filling duration, and greenness, and eventually decreased grain yield up to?~?28%. The early maturity genotypes resulted in higher yields under stress conditions by a stress-avoidance mechanism. Among 14 SSR markers, GWM577 was positively correlated with yield, and WMS3062, GWM261, and WMS1025 had positive correlations with longevity under stress. Accordingly, WMS3062 and GWM261 can be used to determine high yield and early maturity genotypes. Furthermore, GWM114 showed a positive correlation with TKW, indicating their usefulness for grouping wheat genotypes and for identifying heat-related markers. Since the crossing of the genetically distant genotypes can create more diverse populations, the results could be applied to plan breeding projects to establish more diverse populations for different chromosomal locations and traits under heat stress conditions. Moreover, our findings demonstrated that the morphological and molecular analyses could be useful for describing wheat genetic variation of heat tolerance.

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188.
Co-delivery of small chemotherapeutic molecules and nucleic acid materials via targeted carriers has attracted great attention for treatment of resistant tumors and reducing adverse effects. In this study, a targeted carrier for co-delivery was prepared based on low-molecular weight polyethylenimine (LMW PEI). Paclitaxel (PTX) was covalently conjugated onto PEI via a succinate linker. The PEI conjugate was decorated with L-DOPA in order to target large neutral amino acid transporter-1 (LAT-1) that is over-expressed on various cancer cells. This PEI conjugate was complexed with human ABCB1 shRNA plasmid to down-regulate the expression of P-glycoprotein, as one of the major efflux pumps inducing resistance against chemotherapeutics. The formation of PEI conjugate enhanced the solubility of PTX and resulted in the condensation and protection of plasmid DNA in nanosized polyplexes. The results of targeted delivery into the cells demonstrated that PEI conjugate transferred the payloads to the cells over-expressing LAT-1 transporter, while the biological effects on the cells lacking the transporter was negligible. Also, shRNA-mediated down-regulation of P-gp led to the increase of toxic effects on the cells over-expressing P-gp. This study suggests a promising approach for co-delivery of small molecules and nucleic acid materials in a targeted manner for cancer therapy.  相似文献   
189.
The human adenovirus E4 ORF 6 34 kDa oncoprotein (E4 34k), in concert with the 55 kDa product of E1b, prevents concatenation of viral genomes in infected cells, inhibits the repair of double strand breaks (DSBs) in the viral genome, and inhibits V(D)J recombination in a plasmid transfection assay. These activities are consistent with a general inhibition by the E4 34k and E1b 55k proteins of DSB repair by non-homologous end joining (NHEJ) on extrachromosomal substrates. To determine whether inhibition of NHEJ extends to repair of DSBs in the cell chromosome, we have examined the effects of E4 34k on repair of chromosomal DSBs induced by ionizing radiation in a cell line in which E4 34k expression and biological activity is inducible and E1b 55k is produced constitutively. We demonstrate that in this cell line, induction of E4 34k inhibits chromosomal DSB repair. Recently, it has been shown that in infected cells, E4 34k and the adenovirus E1b 55k proteins cooperate to destabilize Mre11 and Rad50, components of mammalian NHEJ systems. Consistent with this, induction of expression of E4 34k in the inducible cell line also reduces the steady state level of Mre11 protein.  相似文献   
190.
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