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Morphine (30 mg/kg i.p.) produced a hypothermic effect in restrained rats which was antagonized by naloxone pretreatment (10 mg/kg s.c.). This hypothermia was inhibited by deprenyl pretreatment (5 mg/kg i.p.) and by beta-phenylethylamine treatment (25 mg/kg i.p.). However, the effect of morphine was partially potentiated when a higher dose of deprenyl (10 mg/kg i.p.) was administered. Pretreatment with clorgyline (1 mg/kg i.p.) potentiated the morphine-induced hypothermia. In contrast, the effect of morphine was antagonized when a higher dose of clorgyline was used (5 mg/kg i.p.). Based on these results, a possible role of brain serotonin and dopamine in the thermoregulatory effects of morphine is proposed in this paper. 相似文献
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Mandruzzato G Antsaklis A Botet F Chervenak FA Figueras F Grunebaum A Puerto B Skupski D Stanojevic M;WAPM 《Journal of perinatal medicine》2008,36(4):277-281
Perinatal mortality and morbidity is markedly increased in intrauterine growth restricted (IUGR) fetuses. Prenatal identification of IUGR is the first step in clinical management. For that purpose a uniform definition and criteria are required. The etiology of IUGR is multifactorial and whenever possible it should be assessed. When the cause is of placental origin, it is possible to identify the affected fetuses. The major complication is chronic fetal hypoxemia. By monitoring the changes of fetal vital functions it is thus possible to improve both management and outcome. The timing of delivery is crucial but the optimal management scheme has not yet been identified. When IUGR is identified at very early gestational ages, serial assessments of the risk of continuing the in utero fetal life under adverse conditions versus the risks of the prematurity should be performed. Delivery of IUGR fetuses should take place in centers where appropriate neonatal assistance can be provided. Careful monitoring of the IUGR fetus during labor is crucial as the IUGR fetus can quickly decompensate once uterine contractions have started. 相似文献
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Brazdil Vojtech Kala Petr Hudec Martin Poloczek Martin Kanovsky Jan Stipal Roman Jerabek Petr Bocek Otakar Pail Martin Brazdil Milan 《Clinical autonomic research》2022,32(1):9-17
Clinical Autonomic Research - Takotsubo syndrome (TTS), also known as stress cardiomyopathy or “broken heart” syndrome, is a mysterious condition that often mimics an acute myocardial... 相似文献
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Andrei V Alexandrov Martin Köhrmann Lauri Soinne Georgios Tsivgoulis Andrew D Barreto Andrew M Demchuk Vijay K Sharma Robert Mikulik Keith W Muir Gordon Brandt John Alleman James C Grotta Christopher R Levi Carlos A Molina Maher Saqqur Dimitris Mavridis Theodora Psaltopoulou Milan Vosko Peter D Schellinger 《Lancet neurology》2019,18(4):338-347
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Milan Toma Shelly Singh-Gryzbon Elisabeth Frankini Zhenglun Wei Ajit P. Yoganathan 《Materials》2022,15(9)
This paper provides a review of engineering applications and computational methods used to analyze the dynamics of heart valve closures in healthy and diseased states. Computational methods are a cost-effective tool that can be used to evaluate the flow parameters of heart valves. Valve repair and replacement have long-term stability and biocompatibility issues, highlighting the need for a more robust method for resolving valvular disease. For example, while fluid–structure interaction analyses are still scarcely utilized to study aortic valves, computational fluid dynamics is used to assess the effect of different aortic valve morphologies on velocity profiles, flow patterns, helicity, wall shear stress, and oscillatory shear index in the thoracic aorta. It has been analyzed that computational flow dynamic analyses can be integrated with other methods to create a superior, more compatible method of understanding risk and compatibility. 相似文献
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Barry N. Duplantis Milan Osusky Crystal L. Schmerk Darrell R. Ross Catharine M. Bosio Francis E. Nano 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(30):13456-13460
All bacteria share a set of evolutionarily conserved essential genes that encode products that are required for viability. The great diversity of environments that bacteria inhabit, including environments at extreme temperatures, place adaptive pressure on essential genes. We sought to use this evolutionary diversity of essential genes to engineer bacterial pathogens to be stably temperature-sensitive, and thus useful as live vaccines. We isolated essential genes from bacteria found in the Arctic and substituted them for their counterparts into pathogens of mammals. We found that substitution of nine different essential genes from psychrophilic (cold-loving) bacteria into mammalian pathogenic bacteria resulted in strains that died below their normal-temperature growth limits. Substitution of three different psychrophilic gene orthologs of ligA, which encode NAD-dependent DNA ligase, resulted in bacterial strains that died at 33, 35, and 37 °C. One ligA gene was shown to render Francisella tularensis, Salmonella enterica, and Mycobacterium smegmatis temperature-sensitive, demonstrating that this gene functions in both Gram-negative and Gram-positive lineage bacteria. Three temperature-sensitive F. tularensis strains were shown to induce protective immunity after vaccination at a cool body site. About half of the genes that could be tested were unable to mutate to temperature-resistant forms at detectable levels. These results show that psychrophilic essential genes can be used to create a unique class of bacterial temperature-sensitive vaccines for important human pathogens, such as S. enterica and Mycobacterium tuberculosis. 相似文献