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81.
Jochen Moll Christian Kexel Hamed Milanchian Mit Balvantray Bhavsar John Howard Barker 《Ultrasound in medicine & biology》2019,45(2):605-611
Approximately 6.3 million fractures occur each year in the United States alone. Accurately monitoring the progression of fracture healing is essential to be able to advise patients when it is safe to return to normal activity. The most common method used to confirm and monitor fracture healing is the acquisition of multiple radiographic images over the many months required for healing. This imaging method uses large expensive equipment and exposes patients to high levels of ionizing radiation. In the study described here, we tested another technology for monitoring fracture healing that could minimize the need for multiple radiographic images. We tested a piezoelectric transducer fixed to the surface of a bone that uses electromechanical impedance spectroscopy to measure simulated fractures and transmits the measurement data to an acoustic receiver located externally on the skin surface. 相似文献
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83.
Nina Vyas Kawa Manmi Qianxi Wang Ananda J. Jadhav Mostafa Barigou Rachel L. Sammons Sarah A. Kuehne A. Damien Walmsley 《Ultrasound in medicine & biology》2019,45(5):1044-1055
Bacterial biofilms are a cause of contamination in a wide range of medical and biological areas. Ultrasound is a mechanical energy that can remove these biofilms using cavitation and acoustic streaming, which generate shear forces to disrupt biofilm from a surface. The aim of this narrative review is to investigate the literature on the mechanical removal of biofilm using acoustic cavitation to identify the different operating parameters affecting its removal using this method. The properties of the liquid and the properties of the ultrasound have a large impact on the type of cavitation generated. These include gas content, temperature, surface tension, frequency of ultrasound and acoustic pressure. For many of these parameters, more research is required to understand their mechanisms in the area of ultrasonic biofilm removal, and further research will help to optimise this method for effective removal of biofilms from different surfaces. 相似文献
84.
Parental care is found widely across animal taxa and is manifest in a range of behaviours from basic provisioning in cockroaches to highly complex behaviours seen in mammals. The evolution of parental care is viewed as the outcome of an evolutionary cost/benefit trade-off between investing in current and future offspring, leading to the selection of traits in offspring that influence parental behaviour. Thus, level and quality of parental care are affected by both parental and offspring genetic differences that directly and indirectly influence parental care behaviour. While significant research effort has gone into understanding how parental genomes affect parental, and mostly maternal, behaviour, few studies have investigated how offspring genomes affect parental care. In this review, we bring together recent findings across different fields focussing on the mechanism and genetics of offspring effects on maternal care in mammals. 相似文献
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86.
A. Armentia S. Martín-Armentia A. Moral D. Montejo B. Martin-Armentia R. Sastre S. Fernández A. Corell D. Fernandez 《Allergologia et immunopathologia》2019,47(4):350-356
Introduction and objectivesBiological aerosols play a vital role in the interactions between the atmosphere, biosphere, climate and public health and fungal spores are a component with allergic importance.We constructed a database in Castile & Leon (Spain) and carry out molecular-level component-resolved diagnosis to complete the air quality study carried out since 2006 by our aerobiological network (RACYL) to aid clinical diagnosis and treatment.MethodsWe reviewed a database of 19,774 patients (adults and children) with allergic respiratory disease treated in our unit during the last 12 years. We also made a component-resolved diagnosis of the molecules involved in the pathology in a randomly selected population of 150 patients.ResultsThe dimeric glycoprotein Alt a1 from Alternaria is the most prevalent and most useful allergen in the diagnosis of patients with allergy to fungi in our area (94.4%), followed by enolase Alt a 6 (Alternaria), ribonuclease Asp f 1 of Aspergillus and mannitol dehydrogenase from Cla h 8 (Cladosporium).ConclusionsOur results have helped determine which spore molecules are most-closely associated with allergies. Molecular analysis will be useful to determine more accurate and useful immunotherapy in these patients. 相似文献
87.
88.
《Clinical microbiology and infection》2019,21(12):1563.e1-1563.e3
ObjectivesProper diagnosis of invasive aspergillosis is challenging because conventional methods lack sensitivity and are complicated by time-consuming incubation processes. To meet the requirement for early diagnosis the new Aspergillus-specific point-of-care test LFA-IMMY™ was evaluated with respect to the ability to accurately detect Aspergillus in bronchoalveolar fluids and sputa, and to clarify the potential of cross-reactivity with other fungal pathogens.MethodsRespiratory specimens (n = 398) from non-selected patients (n = 390) underwent either fungal microscopy, culture or both before Aspergillus lateral flow assay (LFA-IMMY) testing.ResultsFor Aspergillus culture- and microscopy-positive samples, sensitivity (48/52) and specificity (44/48) were 92% (95% CI 8.0%–9.7%) and 91% (95% CI 7.9%–9.7%), respectively; cross-reactivity was documented with non-Aspergillus pathogens.ConclusionLFA-IMMY is a reliable diagnostic tool for the detection of Aspergillus in respiratory samples. 相似文献
89.
Periosteal new bone formation (PNBF) is a common finding in a large spectrum of diseases. In clinical practice, the morphology and location of periosteal lesions are frequently used to assist in the differential diagnosis of distinct bone conditions. Less commonly reported is the presence of PNBF on the ribs. This contrasts with the data retrieved from the study of skeletonized human remains that shows a high frequency of cases and a strong, albeit not specific, association between periosteal rib lesions and pulmonary conditions (e.g. tuberculosis). Despite that, an overall disagreement regarding the specificity and non‐specificity of periosteal reactions exists in the study of dry bone remains. The insufficient number of clinical models exploring the morphology and the pathophysiology of PNBF's and the lack of systematic studies of pathological samples with a known diagnosis are claimed as major reasons for the disagreements. This study aimed to describe and compare the macroscopic and the histomorphologic appearance of periosteal rib lesions and to discuss their usefulness as diagnostic indicators. To pursue this goal, an assemblage of 13 rib samples (males = 11, females = 2, mean age‐at‐death = 36.6 years old) was collected from the Luis Lopes Skeletal Collection (Museu Nacional de História Natural e da Ciência, Universidade de Lisboa, Portugal). The assemblage belongs to individuals who died from pulmonary‐TB (group 1), non‐TB pulmonary infections (group 2) and other conditions (group 3). Prior to sample preparation, the ribs were visually inspected and the PNBF described according to its thickness, the degree of cortical integration and the type of new bone formed (e.g. woven, lamellar or both). After sampling, each bone sample was prepared for histological analysis under plane and polarized light microscopy. Macroscopically, the results showed no differences in the new bone composition between cause‐of‐death groups. Only slight differences in the degree of cortical integration, which was most frequently classified as mild to high in the pulmonary‐TB group, were observed. Histologically, no distinguishing features were identified by pathological group. However, new bone microarchitectures were observed compatible with (1) acute, fast‐growing processes (e.g. spiculated reactions), (2) long‐standing processes with a rapid bone formation (e.g. appositional layering of bone) and/or (3) chronic, slow‐growing processes (e.g. layers of compact lamellae). To some extent, these distinct rates of disease progression resonate with the cause‐of‐death listed for some individuals. Despite the small sample size, the results of this investigation are in agreement with previous studies, according to which the macroscopic and histological appearance of periosteal formations are not specific for a particular pathological conditions. Nevertheless, the results support the conclusion that the morphology of periosteal lesions is a good biological indicator for inferring the rate of progression and duration of pathological processes. This study provides important reference data regarding the histomorphology of periosteal lesions that can be used for comparative purposes, as well as to narrow down the differential diagnosis in unidentified skeletal remains. 相似文献