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The advent of interventional MR imaging techniques as well as their adoption to guide percutaneous biopsies and aspirations has served as a further step along a series of technical refinements that commenced with the implementation of image-guided approaches for tissue sampling. Nowadays, the practice of and the expectations from these procedures are quite different from those of the blind percutaneous thrusts performed in the late nineteenth and early twentieth centuries. As the field of interventional MR imaging continues to flourish and to attract more radiologists who realize the many opportunities that this technology can offer to their patients, there is a need for a full comprehension of the concepts, techniques, limitations, and cost-effectiveness of MR imaging guidance to present this service to clinical partners in the appropriate setting. Radiologists should also recognize the need for their significant involvement in the technical aspects of MR-guided procedures, because several user-defined parameters and trajectory decisions can alter device visualization in the MR imaging environment and hence affect procedure safety.  相似文献   
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In spite of recent advances in perinatal care and an increase in survival of extremely preterm infants over the last few years, there remains a lack of consensus about practical aspects of resuscitation of extremely preterm infants born before 27?weeks' gestation. With this in the background, the working group of one of the Perinatal Networks in London, UK, set out to conduct a survey to explore the opinions of the doctors and nurses on resuscitation practices of infants born before 27?weeks' gestation, with the aim of developing consensus guidelines. The working group emailed a questionnaire to all neonatal units within the Perinatal Network to seek the views of paediatric medical and nursing staff on resuscitation of infants born at <27?weeks' gestation. The questionnaire was returned anonymously by post. The responses highlighted the difference of opinion that currently exists amongst the clinicians and nurses across the world around the resuscitation practices of extremely preterm infants; yet at the same time, there seemed to be some consensus on certain issues. Based on the survey (questionnaire) results and already existing literature, the working group of the North West London Perinatal Network (NWLPN) produced and implemented specific consensus guidelines on practical aspects of resuscitation for infants born before 27?weeks' gestation for the network. The network plans to audit these guidelines in future and also produce a parent information leaflet explaining the relevance of these guidelines.  相似文献   
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Stroke, whether hemorrhagic or ischemic in nature, has the ability to lead to devastating and debilitating patient outcomes, which not only has direct implications from a healthcare standpoint, but its effects are longstanding and they impact the community as a whole. For decades, the goal of advancement and refinement in imaging modalities has been to develop the most precise, convenient, widely available and reproducible interpretable modality for the detection of stroke, not only in its hyperacute phase, but a method to be able to predict its evolution through the natural course of disease. Diagnosis is one of the most important initial roles, which imaging fulfills after the identification of existent pathology. However, imaging fulfills an even more important goal by using a combination of imaging modalities and their precise interpretation, which lends itself to understanding the mechanisms and pathophysiology of underlying disease, and therefore guides therapeutic decision-making in a patient-tailored fashion. This review explores the most commonly used brain imaging modalities, computer tomography, and magnetic resonance imaging, with an aim to demonstrate their dynamic use in uncovering stroke mechanism, facilitating prognostication, and potentially guiding therapy.  相似文献   
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ObjectivesWe aimed to study the clinical state and prognosis of patients with unilateral retinoblastoma who were being treated at a paediatric comprehensive cancer centre in a limited-resource country, to assess the different phases of treatment and the success of different, more complex real-life models.SubjectsIn this retrospective study, we created a snapshot of our retinoblastoma database for the period between 2007 and 2015. Patients whose data were included in the study were followed up until 2016. Out of a total of 744 screened patients, we included data of 248 patients who had been diagnosed with unilateral retinoblastoma.ResultsAs classified as per the International Retinoblastoma Classification, 1 patient presented with group A, 21 with group B, 39 with group C, 104 with group D and 83 with group E retinoblastoma. Chemotherapy was the initial line of treatment in 115 patients and enucleation in 133 others. Later, 141 patients (56.9%) required further management. Patients had a mean ocular survival time of 20.8 months. Nine patients developed extraocular disease at a later stage of management: five after upfront enucleation and four after neoadjuvant chemotherapy. Mean overall survival time stood at 90.2 months. Four and three deaths were recorded in groups D and E, respectively. A single patient died in the initial chemotherapy arm, while six passed away in the initial enucleation arm.ConclusionOur study highlights the importance of initial chemotherapy and close follow-up after enucleation of classes D and E affected eyes even in absence of germline mutations.Subject terms: Paediatrics, Retinal diseases  相似文献   
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A simple and sensitive spectrophotometric method for the determination of three catecholamines namely dopamine hydrochloride (DO.HCl), dobutamine hydrochloride (DOB.HCl) and vanillymandelic acid (VMA), in both pure form or in their commercially available pharmaceutical formulations or urine samples of schizopherinic patients is described. The method is based on the reaction of diazotized 4‐aminoantipyrine (4‐AAP) with catecholamines in a basic medium (pH = 10–11) to yield pink‐coloured products having absorption maxima at 500, 505 and 480 nm for DO.HCl, VMA and DOB.HCl, respectively. Before carrying out Beer's Law, different experimental conditions, such as time, temperature, sequence of addition, and pH are optimized. The coloured species obeyed Beer's Law in the range of 47.4–417.2, 59.45–445.9 and 67.57–405.4 mg/L for DO.HCl, VMA and DOB.HCl, respectively. The molar absorptivity values as obtained from Beer's Law data were found to be 2.979 × 104, 4.39 × 104 and 1.036 × 104 L mol?1 cm?1, while Sandell's sensitivity values were observed to be 3 × 10?3, 4.4 × 10?3 and 1.3 × 10?3 µg cm2? for DO.HCl, VMA and DOB.HCl, respectively. Common excipients did not interfere with the proposed method. The results of the proposed method compare favourably with those of official methods. The proposed method offers simplicity, reliability, rapidity, and accuracy compared to the existing methods. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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