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1.
CdS thin films and bulk precipitates were obtained by chemical bath deposition (CBD) in a well-closed reactor. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, thermal analysis, elemental analysis and leaching have been used to characterize solids and thin films. It has been shown that the proportion of cadmium cyanamide in solids may vary from about 50% to 2% according to physicochemical conditions in solution (time after CBD, ammonia concentration) and that CdO results from CdCN2 after air annealing of thin films. This last step also increases the crystallinity of the films.  相似文献   
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The histamine H3 receptor was initially identified as a presynaptic autoreceptor controlling histamine release and synthesis in the brain. It belongs to the superfamily of G protein-coupled receptors. The existence of the H3 receptor which has not yet been cloned was definitely established by the design of highly potent and selective agonists (R-(-)-alpha-methylhistamine, imetit) and antagonists (thioperamide, clobenpropit). These receptors also occur as heteroreceptors both in the central nervous system and on peripheral neurons of the gastrointestinal and bronchial tract, where they regulate the release of a variety of neurotransmitters. In the cardiovascular system, histamine H3 receptors are mainly located presynaptically on the postganglionic sympathetic nerve fibers innervating the blood vessels and the heart. Their activation leads to the inhibition of noradrenaline release and consequently to the reduction of the neurogenic vasopressor and cardiostimulatory responses. The presence of such receptors has been shown both in vitro (human, pig, guinea-pig, rabbit, rat isolated tissues) and in vivo (rat, guinea-pig). The vascular and cardiac presynaptic H3 receptors may be activated by endogenous histamine. The vascular H3 receptors appear to be operative in hypertension and interact with presynaptic alpha 2-adrenoceptors. Postsynaptic vasodilatatory H3 receptors have been detected in several vascular beds as well. H3 receptor ligands affect basal cardiovascular parameters in conscious and anesthetized guinea-pigs but not rats. Presynaptic H3 receptors may play a role in the pathophysiology of headache and cardiac ischemia.  相似文献   
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The response of the rabbit utero-ovarian ligament to catecholamines has been studied in vitro, with contractile activity being recorded isometrically from whole rabbit ligaments obtained under various hormonal conditions. Both the catecholamines norepinephrine (NE) and epinephrine (EPI) produced dose-dependent (10(-2) mug/ml threshold; 10(2) mug/ml maximum) tetanic contractions of rabbit ligament. There was no difference (P less than 0.05) between estrous and ovulatory ligaments either in terms of the dose-response curves or maximal force of contraction. Both agonists were 100% antagonized by the alpha-blockers, phentolamine and phenoxybenzamine. The beta-agonist, isoproterenol, had little effect on ligament tonus but did inhibit spontaneous activity and attenuated the response to both NE and EPI. Propranolol, a beta-blocker, slightly (less than 10%) potentiated the stimulatory effects of NE and EPI. It is concluded that the utero-ovarian ligament of the rabbit contains predominately alpha-stimulatory and possibly weak beta-inhibitory receptors analogous to receptors in ovarian and oviductal smooth muscles.  相似文献   
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may lead to coronavirus disease 2019 (COVID-19) which, in turn, may be associated with multiple organ dysfunction. In this review, we present advantages and disadvantages of cannabidiol (CBD), a non-intoxicating phytocannabinoid from the cannabis plant, as a potential agent for the treatment of COVID-19. CBD has been shown to downregulate proteins responsible for viral entry and to inhibit SARS-CoV-2 replication. Preclinical studies have demonstrated its effectiveness against diseases of the respiratory system as well as its cardioprotective, nephroprotective, hepatoprotective, neuroprotective and anti-convulsant properties, that is, effects that may be beneficial for COVID-19. Only the latter two properties have been demonstrated in clinical studies, which also revealed anxiolytic and antinociceptive effects of CBD (given alone or together with Δ9-tetrahydrocannabinol), which may be important for an adjuvant treatment to improve the quality of life in patients with COVID-19 and to limit post-traumatic stress symptoms. However, one should be aware of side effects of CBD (which are rarely serious), drug interactions (also extending to drugs acting against COVID-19) and the proper route of its administration (vaping may be dangerous). Clearly, further clinical studies are necessary to prove the suitability of CBD for the treatment of COVID-19.  相似文献   
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Our study aimed to examine the effects of hypertension and the chronic administration of the fatty acid amide hydrolase (FAAH) inhibitor URB597 on vascular function and the endocannabinoid system in spontaneously hypertensive rats (SHR). Functional studies were performed on small mesenteric G3 arteries (sMA) and aortas isolated from SHR and normotensive Wistar Kyoto rats (WKY) treated with URB597 (1 mg/kg; twice daily for 14 days). In the aortas and sMA of SHR, endocannabinoid levels and cannabinoid CB1 receptor (CB1R) expression were elevated. The CB1R antagonist AM251 diminished the methanandamide-evoked relaxation only in the sMA of SHR and enhanced the vasoconstriction induced by phenylephrine and the thromboxane analog U46619 in sMA in SHR and WKY. In the sMA of SHR, URB597 elevated anandamide levels, improved the endothelium-dependent vasorelaxation to acetylcholine, and in the presence of AM251 reduced the vasoconstriction to phenylephrine and enhanced the vasodilatation to methanandamide, and tended to reduce hypertrophy. In the aortas, URB597 elevated endocannabinoid levels improved the endothelium-dependent vasorelaxation to acetylcholine and decreased CB1R expression. Our study showed that hypertension and chronic administration of URB597 caused local, resistance artery-specific beneficial alterations in the vascular endocannabinoid system, which may bring further advantages for therapeutic application of pharmacological inhibition of FAAH.  相似文献   
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Thyroid cancers (TCs) are the most common tumors of the endocrine system and a constant rise in the number of TC cases has been observed for the past few decades. TCs are one of the most frequent tumors in younger adults, especially in women, therefore early diagnosis and effective therapy are especially important. Ultrasonography examination followed by fine needle biopsy have become the gold standard for diagnosis of TCs, as these strategies allow for early-stage detection and aid accurate qualification for further procedures, including surgical treatment. Despite all the advancements in detection and treatment of TCs, constant mortality levels are still observed. Therefore, a novel generation line of targeted treatment strategies is being developed, including personalized therapies with kinase inhibitors. Recent molecular studies on TCs demonstrate that kinase inhibitor-based therapies might be considered as the most promising. In the past decade, new kinase inhibitors with different mechanisms of action have been reported and approved for clinical trials. This review presents an up-to-date picture of new approaches and challenges of inhibitor-based therapies in treatment of TCs, focusing on the latest findings reported over the past two years.  相似文献   
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Palmitic acid (C16:0) is the most abundant saturated fatty acid in animals serving as a substrate in synthesis and β-oxidation of other lipids, and in the modification of proteins called palmitoylation. The influence of dietary palmitic acid on protein S-palmitoylation remains largely unknown. In this study we performed high-throughput proteomic analyses of a membrane-enriched fraction of murine liver to examine the influence of a palm oil-rich diet (HPD) on S-palmitoylation of proteins. HPD feeding for 4 weeks led to an accumulation of C16:0 and C18:1 fatty acids in livers which disappeared after 12-week feeding, in contrast to an accumulation of C16:0 in peritoneal macrophages. Parallel proteomic studies revealed that HPD feeding induced a sequence of changes of the level and/or S-palmitoylation of diverse liver proteins involved in fatty acid, cholesterol and amino acid metabolism, hemostasis, and neutrophil degranulation. The HPD diet did not lead to liver damage, however, it caused progressing obesity, hypercholesterolemia and hyperglycemia. We conclude that the relatively mild negative impact of such diet on liver functioning can be attributed to a lower bioavailability of palm oil-derived C16:0 vs. that of C18:1 and the efficiency of mechanisms preventing liver injury, possibly including dynamic protein S-palmitoylation.  相似文献   
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Gamma rays and electrons with kinetic energy up to 10 MeV are routinely used to sterilize biomaterials. To date, the effects of irradiation upon human acellular dermal matrices (hADMs) remain to be fully elucidated. The optimal irradiation dosage remains a critical parameter affecting the final product structure and, by extension, its therapeutic potential. ADM slides were prepared by various digestion methods. The influence of various doses of radiation sterilization using a high-energy electron beam on the structure of collagen, the formation of free radicals and immune responses to non-irradiated (native) and irradiated hADM was investigated. The study of the structure changes was carried out using the following methods: immunohistology, immunoblotting, and electron paramagnetic resonance (EPR) spectroscopy. It was shown that radiation sterilization did not change the architecture and three-dimensional structure of hADM; however, it significantly influenced the degradation of collagen fibers and induced the production of free radicals in a dose-dependent manner. More importantly, the observed effects did not disrupt the therapeutic potential of the new transplants. Therefore, radiation sterilization at a dose of 35kGy can ensure high sterility of the dressing while maintaining its therapeutic potential.  相似文献   
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