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991.
Human immunodeficiency virus-acquired immunodeficiency syndrome continues to be a major global public health issue, having claimed almost 33 million lives to date. Due to the high cost of antiretroviral treatment, access to these drugs remains difficult for vulnerable populations, such as migrants and people living in prisons, who often do not have health insurance. These factors lead to poorer health outcomes and higher transmission rates. The personal importation scheme for unapproved generics from foreign countries is one option to access affordable human immunodeficiency virus treatment. However, the risk of importing falsified medicine remains high, and the quality control of unapproved drugs is lacking. In this context, three CE methods for the analysis of nine antiviral drugs found in commercial pharmaceutical formulations were evaluated. The selected compounds were emtricitabine, tenofovir disoproxil, tenofovir alafenamide, rilpivirine, efavirenz, raltegravir, dolutegravir, abacavir, and lamivudine. The developed methods were successfully applied to determine the active pharmaceutical ingredients of commercial formulations and unapproved generics. The quality control of unapproved generics by CE is an attractive approach due to its good standard of quality, low cost, ecofriendliness, and ease of implementation.  相似文献   
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The key structural feature of the new phosphoramidites is a paracyclophane scaffold in which two aryl rings are tethered by both a 1,8‐biphenylene unit and a O?P?O bridge. Suitable aryl substituents generate planar chirality. The corresponding gold(I) complexes promote the cycloisomerization of prochiral nitrogen‐tethered dienynes. These reactions afford bicyclo[4.1.0]heptene derivatives displaying three contiguous stereogenic centers, with very high diastereoselectivity and up to 95 % ee.  相似文献   
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Conjugated graft copolymers consisting of a poly(3‐hexylthiophene) (P3HT) backbone and poly(9,9'‐dioctylfluorene) side chains (PF) with different grafting degrees were synthesized by the CuAAC reaction. The properties of these materials were studied by UV‐Vis and fluorescence spectroscopy. The former technique provides insight in their self‐assembly, while the latter is used to study the energy funneling from the PF side chains to the P3HT backbone. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1252–1258  相似文献   
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We propose a new spatial covariance model with a single wave effect and a finite range. The construction of this model is based on a radial kernel composed of two concentric spheres and the finite range enables us to obtain an exact simulation from the circulant embedding method. This model responds to the lack of efficient covariance functions to model patterns characterized by concentration areas surrounded by gaps. We compare the single wave model to other existing hole effect models such as the Bessel model, the damped cosine model and the cardinal sine model.  相似文献   
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