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31.
Russian Journal of Bioorganic Chemistry - Pyridazines hold considerable interest relative to pharmacologically active molecules. The pyridazine compounds are exhibited different types of...  相似文献   
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Rapid urbanization, global trade, and the exceptionally great numbers of worldwide visitors during Hajj and Umrah have all placed the Kingdom of Saudi Arabia at a significant risk of introducing several vector-borne tropical diseases, such as dengue fever virus (DENV) infection. In this study we estimated DENV infection cost of illness (COI) in Saudi Arabia in the period 2013–2017, by processing national data including all declared cases recorded in referral centers in the western region, being the endemic region of the country. Using a statistically validated predictive model that was built on a representative sample of 717 laboratory-confirmed cases of DENV infection, direct costs, due to care-related expenditures, were estimated by applying the predictive equation to national data. However, indirect costs, which are due to productivity loss, were estimated using the human capital model based on gross domestic product adjusted for invalidity duration. Further, under-reporting was adjusted by using an expansion factor EF = 3. We observed highest estimated costs in 2016 with over US$168.5 Million total costs, including direct (US$29.0 Million) and indirect (US$139.5 Million) costs, for a total 4415 confirmed cases. The total DENV COI for the five years was estimated as US$551.0 Million for a total 15,369 patients (59.7%) out of 25,745 declared cases, resulting in an average cost of US$11 947.6 by patient. Depending on the year, productivity years loss costs accounted for 63.3% to 83.8% of the estimated total costs. Dengue has a substantial local economic burden that costs US$110.2 Million per year, stressing the urgent need for an effective national prevention strategy to perform considerable cost-savings besides reducing morbidity.  相似文献   
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Imidazolidin-4-one is used as a recoverable organocatalyst for the asymmetric Diels-Alder reaction in the presence of catalytic amount of dicationic ionic liquid and trifluoroacetic acid as a co-catalyst. The Diels-Alder reaction between model substrate cyclopentadiene and crotonaldehyde gave the product in 95% conversion and 87% ee of the endo-product. The catalyst was shown better reusability when the 20 mol% of dicationic ionic liquid was used and catalyst was reused upto 5 cycles, conversion remains upto 3 recycles but ee of endo- 9 was slightly droped.  相似文献   
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Parallel evolution in phenotype may result when closely related taxa are adapting in the face of similar ecological pressures. Here, we discuss possible parallelism in shell morphology in the context of the microgeographic phylogeography of two conchologically distinct sympatric hydrocenid snails inhabiting a limestone outcrop and its cave system, Georissa pyrrhoderma and Georissa silaburensis, respectively, at Mount Silabur in Sarawak, Malaysian Borneo. Our results show a certain degree of morphological parallelism of a third, possibly new, cryptic Georissa species within the same cave that strongly diverged from its above-ground sister species, G. pyrrhoderma. We found that both sympatric cave species have shifted from a more sculptured, conical shell toward a broader, less sculptured form.  相似文献   
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Wolbachia are maternally inherited endosymbiotic bacteria found within many insect species. Aedes mosquitoes experimentally infected with Wolbachia are being released into the field for Aedes‐borne disease control. These Wolbachia infections induce cytoplasmic incompatibility which is used to suppress populations through incompatible matings or replace populations through the reproductive advantage provided by this mechanism. However, the presence of naturally occurring Wolbachia in target populations could interfere with both population replacement and suppression programs depending on the compatibility patterns between strains. Aedes aegypti were thought to not harbor Wolbachia naturally but several recent studies have detected Wolbachia in natural populations of this mosquito. We therefore review the evidence for natural Wolbachia infections in A. aegypti to date and discuss limitations of these studies. We draw on research from other mosquito species to outline the potential implications of natural Wolbachia infections in A. aegypti for disease control. To validate previous reports, we obtained a laboratory population of A. aegypti from New Mexico, USA, that harbors a natural Wolbachia infection, and we conducted field surveys in Kuala Lumpur, Malaysia, where a natural Wolbachia infection has also been reported. However, we were unable to detect Wolbachia in both the laboratory and field populations. Because the presence of naturally occurring Wolbachia in A. aegypti could have profound implications for Wolbachia‐based disease control programs, it is important to continue to accurately assess the Wolbachia status of target Aedes populations.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - Plant cells develop defence mechanisms in response to mutagen stress which leads to modulation of certain metabolic and defensive pathways. Owing to...  相似文献   
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Molecular Biology Reports - Despite the advancements in primary brain tumour diagnoses and treatments, the mortality rate remains high, particularly in glioblastoma (GBM). Chemoresistance,...  相似文献   
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Mycopathologia - Candida albicans has been reported globally as the most widespread pathogenic species contributing candidiasis from superficial to systemic infections in immunocompromised...  相似文献   
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