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Molecular Imaging and Biology - To evaluate, if clinically translatable ferumoxytol nanoparticles can be used for in vivo detection and quantification of stem cell transplants with magnetic...  相似文献   
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New anionic rhodium(iii) complexes, obtained by a simple reaction of RhCl3 with organic chlorides (derivatives of imidazole and pyridine), have been employed as catalysts for hydrosilylation (reduction) of acetophenone derivatives. The reactions, in which 1,1,1,3,5,5,5-heptamethyltrisiloxane was a reducing agent, proceeded in a biphasic system because the above complexes are insoluble in the reaction medium. Thereby easy isolation of the complexes from post-reaction mixtures was possible after reaction completion. This is the first example of the application of rhodium complexes of this type as catalysts for ketone reduction. The complexes have shown high activity and enabled obtaining the hydrosilylation product in a very short time and in the range of low concentrations (0.1 mol%). By using FT-IR in situ analysis that enables measuring product concentrations in real time, a comparison has been made of the catalytic activity for hydrosilylation of acetophenone and methoxyacetophenone isomers shown by four rhodium complexes ([C+][RhCl4]) differing in cations and the most effective catalyst for this process has been distinguished.

Stable rhodium complexes were obtained in a simple way and applied as highly active catalysts for reduction of acetophenone derivatives.  相似文献   
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Objectives: Local anesthetic (LA) intoxication with cardiovascular arrest is a potential fatal complication of regional anesthesia. Lipid resuscitation has been recommended for the treatment of LA‐induced cardiac arrest. Aim of the study was to compare four different rescue regimens using epinephrine and/or lipid emulsion and vasopressin to treat cardiac arrest caused by bupivacaine intoxication. Methods: Twenty‐eight piglets were randomized into four groups (4 × 7), anesthetized with sevoflurane, intubated, and ventilated. Bupivacaine was infused with a syringe driver via central venous catheter at a rate of 1 mg·kg?1·min?1 until circulatory arrest. Bupivacaine infusion and sevoflurane were then stopped, chest compression was started, and the pigs were ventilated with 100% oxygen. After 1 min, epinephrine 10 μg·kg?1 (group 1), Intralipid® 20% 4 ml·kg?1 (group 2), epinephrine 10 μg·kg?1 + Intralipid® 4 ml·kg?1 (group 3) or 2 IU vasopressin + Intralipid® 4 ml·kg?1 (group 4) were administered. Secondary epinephrine doses were given after 5 min if required. Results: Survival was 71%, 29%, 86%, and 57% in groups 1, 2, 3, and 4. Return of spontaneous circulation was regained only by initial administration of epinephrine alone or in combination with Intralipid®. Piglets receiving the combination therapy survived without further epinephrine support. In contrast, in groups 2 and 4, return of spontaneous circulation was only achieved after secondary epinephrine rescue. Conclusions: In cardiac arrest caused by bupivacaine intoxication, first‐line rescue with epinephrine and epinephrine + Intralipid® was more effective with regard to survival than Intralipid® alone and vasopressin + Intralipid® in this pig model.  相似文献   
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Junín virus, the etiological agent of Argentine hemorrhagic fever, causes significant morbidity and mortality. The virus is spread through the aerosolization of host rodent excreta and endemic to the humid pampas of Argentina. Recently, significant progress has been achieved with the development of new technologies (e.g. reverse genetics) that have expanded knowledge about the pathogenesis and viral replication of Junín virus. We will review the pathogenesis of Junín virus in various animal models and the role of innate and adaptive immunity during infection. We will highlight current research regarding the role of molecular biology of Junín virus in elucidating virus attenuation. We will also summarize current knowledge on Junín virus pathogenesis focusing on the recent development of vaccines and potential therapeutics.  相似文献   
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IntroductionIn the last decade, remarkable advances have been made in noninvasive imaging of aortic diseases. The aim of this article was to provide a comprehensive review of these imaging modalities. Echocardiography plays an important role in the diagnosis and follow-up of aortic diseases. Transthoracic echocardiography (TTE) permits adequate assessment of several aortic segments, particularly aortic root and proximal ascending aorta. Transoesophageal echocardiography (TEE) overcomes the limitations of TTE in thoracic aorta assessment. TTE and TEE should be used in a complementary manner. Although TEE is the technique of choice in the diagnosis of aortic dissection, TTE may be used as the initial modality in the emergency setting. Intimal flap in proximal ascending aorta, pericardial effusion/tamponade and left ventricular function can be easily visualised by TTE. TEE information (entry tear location, mechanisms and severity of aortic regurgitation and true lumen compression) is essential for selecting and monitoring surgical and endovascular treatment and detecting possible complications. Computed tomography has the advantage of providing optimum morphological information of the entire aorta and the accuracy of size measurements. Magnetic resonance imaging offers good morphological and dynamic information on the aorta without radiation, although in clinical practice its availability is lower.ConclusionsThe considerable advances in imaging techniques have greatly increased our understanding of aortic diseases. Not only clinical presentation and required information, but also local availability of imaging equipment and staff expertise in this field, should be considered to indicate echocardiography, computed tomography or magnetic resonance, in the assessment of different aortic diseases and their circumstances.  相似文献   
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