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81.
There are only a limited number of drugs proven to be human teratogens including thalidomide, isotretinoin, coumarin derivates, valproic acid, and folate antagonists. In some cases, the combination of 2 drugs may increase the teratogenic risk. The risk of birth defects may also vary with the time at which the drug is administered during pregnancy and the dose. There are some examples of drugs in which the dose has proven to be a major determinant of their teratogenicity in humans. There is more safety information for older than for newer drugs. Proactive teratogen risk counseling should include a critical appraisal of all available data including the consequences of the untreated maternal condition.  相似文献   
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Smart textiles have attracted huge attention due to their potential applications for ease of life. Recently, smart textiles have been produced by means of incorporation of electronic components onto/into conductive metallic yarns. The development, characterizations, and electro-mechanical testing of surface mounted electronic device (SMD) integrated E-yarns is still limited. There is a vulnerability to short circuits as non-filament conductive yarns have protruding fibers. It is important to determine the best construction method and study the factors that influence the textile properties of the base yarn. This paper investigated the effects of different external factors, namely, strain, solder pad size, temperature, abrasion, and washing on the electrical resistance of SMD integrated silver-coated Vectran (SCV) yarn. For this, a Vectran E-yarn was fabricated by integrating the SMD resistor into a SCV yarn by applying a vapor phase reflow soldering method. The results showed that the conductive gauge length, strain, overlap solder pad size, temperature, abrasion, and washing had a significant effect on the electrical resistance property of the SCV E-yarn. In addition, based on the experiment, the E-yarn made from SCV conductive thread and 68 Ω SMD resistor had the maximum electrical resistance and power of 72.16 Ω and 0.29 W per 0.31 m length. Therefore, the structure of this E-yarn is also expected to bring great benefits to manufacturing wearable conductive tracks and sensors.  相似文献   
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Despite the development of COVID-19 vaccines, at present, there is still no approved antiviral drug against the pandemic. The SARS-CoV-2 3-chymotrypsin-like proteases (S-3CLpro) and papain-like protease (S-PLpro) are essential for the viral proliferation cycle, hence attractive drug targets. Plant-based dietary components that have been extensively reported for antiviral activities may serve as cheap sources of preventive nutraceuticals and/or antiviral drugs. A custom-made library of 176 phytochemicals from five West African antiviral culinary herbs was screened for potential dual-target-directed inhibitors of S-3CLpro and S-PLpro in silico. The docking analysis revealed fifteen steroidal saponins (FSS) from Vernonia amygdalina with the highest binding tendency for the active sites of S-3CLpro and S-PLpro. In an optimized docking analysis, the FSS were further docked against four equilibrated conformers of the S-3CLpro and S-PLpro. Three stigmastane-type steroidal saponins (vernonioside A2, vernonioside A4 and vernonioside D2) were revealed as the lead compounds. These compounds interacted with the catalytic residues of both S-3CLpro and S-PLpro, thereby exhibiting dual inhibitory potential against these SARS-CoV-2 cysteine proteases. The binding free energy calculations further corroborated the static and optimized docking analysis. The complexed proteases with these promising phytochemicals were stable during a full atomistic MD simulation while the phytochemicals exhibited favourable physicochemical and ADMET properties, hence, recommended as promising inhibitors of SARS-CoV-2 cysteine proteases.

Vernonia amygdalina derived phytochemicals as potential dual-target directed inhibitors of SARS-CoV-2 proteases from computational study perspective.  相似文献   
85.
Attention deficit/hyperactivity disorder (ADHD) is a neurobehavioral condition found in 5-10% of school-age children and in 2-5% of adults. Stimulants affecting the dopaminergic, noradrenergic and/or serotonergic systems are commonly used for treatment in children and adults, including women of childbearing age. The data on the effects of stimulants (methylphenidate and amphetamines) in pregnancy are generally reassuring, but methylphenidate might slightly increase the rate of cardiac malformations and of spontaneous abortions, while amphetamines might slightly increase the risk for premature birth, low birth weight and other pregnancy complications. Bupropion, a dopamine and norepinephrine reuptake inhibitor, when used as an antidepressant, appears to be safe in pregnancy. The data on the use of atomoxetine, guanfacine and clonidine in pregnancy are scarce. Importantly, there are practically no data on the long-term neurodevelopmental effects of most of these drugs. The published data on the development of children born to methamphetamine-abusing women may be misleading since these women generally use other drugs, including alcohol, and the home environment where the child is raised may not be optimal. The treating physician should judge the need for treatment during pregnancy in relation to the severity of the clinical symptoms. If needed, methylphenidate is preferred over amphetamines because breast feeding is possible. If one uses non-stimulant medications, bupropion seems to be the preferred drug.  相似文献   
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