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991.
Carlos A. Ferri Antonio A. F. Quevedo 《Journal of medical engineering & technology》2013,37(7):553-561
AbstractPeripheral nerve stimulators have widespread among anaesthesiologists and remain a popular technique. However, in commercial devices, the user has to manually adjust stimulus intensity. Thus, the aim of this study is to propose a method that allows automating the current intensity control. An earlier nerve stimulator prototype was modified to add an accelerometer and an sEMG module. The choice of these two sensors is aimed at the possibility of observing the mechanical and electrical responses of the muscle contraction evoked by the stimulation. The tests were performed in two steps. The first step was to observe how the sensors behave during stimulation and muscle contraction. The second step was to implement a control algorithm and to validate the automation technique. Comparing the two methods, no significant differences were found on procedure time (manual: 12.5?±?2.3; automatic: 11.6?±?1.9; ρ?=0.380) and blockade latency time (manual: 11.6?±?1.1; automatic: 11.9?±?1.2; ρ?=0.524). Comparing needle-nerve distance in manual or automatic mode, no significant differences were found for 1.0?mA, 0.8?mA, 0.5?mA and 0.3?mA. We conclude that the technique for automating the current intensity update, using accelerometer and/or electromyography, is satisfactory. Furthermore, we conclude that the use of the accelerometer alone is sufficient for detection of muscle contraction. 相似文献
992.
José Fernando Val-Bernal Ainara Azueta Luis Antonio Ortiz-Rivas Javier Fuentes Roberto Ballestero 《Pathology, research and practice》2013
Hibernomas are uncommon benign lipomatous tumors which show differentiation toward brown fat. To our knowledge, only one case of adrenal hibernoma has been previously reported. We describe a 55-year-old woman showing an incidental, 1.7 cm-hibernoma associated with a 2.6 cm-cortical adenoma producing primary hyperaldosteronism (Conn's syndrome), both in the left adrenal gland. The hibernoma was composed predominantly of univacuolated mature fat cells admixed with small vessels. Scattered areas composed of large multivacuolated pale cells with central or paracentral nuclei, mimicking lipoblasts, accounting for less than 30% of the tumor, were found. These cells lacked nuclear hyperchromasia or marked atypia, were S100-positive, and showed numerous mitochondria reactive with the anti-mitochondrial antibody. A diagnosis of lipoma-like hibernoma was made. Pathologists should be aware of this variant of hibernoma to avoid misdiagnosis and excessive treatment. 相似文献
993.
994.
Martinotti Giovanni Bonanni Laura Barlati Stefano Miuli Andrea Sepede Gianna Prestia Davide Trabucco Alice Palumbo Claudia Massaro Alessandra Olcese Martina D’Ardes Damiano Cipollone Francesco Amore Mario Bondi Emi Russo Mirella Carrarini Claudia Onofrj Marco Sensi Stefano Luca Vita Antonio di Giannantonio Massimo 《Neurological sciences》2021,42(10):3981-3988
Neurological Sciences - Although recent data show that SARS-CoV-2 infection seems to affect the central nervous system (CNS), little is known about the neuropsychiatric effects resulting from this... 相似文献
995.
Anca Barău Amparo Ruiz-Sauri Gerardo Valencia Maria del Carmen Gómez-Mateo Luis Sabater Antonio Ferrandez Antonio Llombart-Bosch 《Virchows Archiv : an international journal of pathology》2013,462(5):541-546
The objectives of this work are to study angiogenesis in pancreatic ductal adenocarcinoma using computerized morphometric and image analysis and to compare the microvascular density in intratumoral and peritumoral areas and normal pancreatic tissue. Microvascular density was analyzed in 60 cases of pancreatic ductal adenocarcinoma and 30 samples of normal pancreatic tissue using an avidin–biotin immunoperoxidase technique with an anti-CD31 antibody. Microvascular density (MVD) was analyzed through digital microimaging and computerized analysis. The blood vessel density in the tumor was significantly higher than in peritumoral areas and in normal pancreatic tissue. Well differentiated pancreatic ductal adenocarcinomas contained higher MVD than poorly differentiated carcinomas. In pancreatic adenocarcinoma, MVD is higher than in peritumoral tissue or normal pancreatic tissue. 相似文献
996.
Grazia P. Nicchia Cinzia Stigliano Angelo Sparaneo Andrea Rossi Antonio Frigeri Maria Svelto 《Journal of molecular medicine (Berlin, Germany)》2013,91(5):613-623
Prohibiting angiogenesis is an important therapeutic approach for fighting cancer and other angiogenic related diseases. Research focused on proteins that regulate abnormal angiogenesis has attracted intense interest in both academia and industry. Such proteins are able to target several angiogenic factors concurrently, thereby increasing the possibility of therapeutic success. Aquaporin-1 (AQP1) is a water channel membrane protein that promotes tumour angiogenesis by allowing faster endothelial cell migration. In this study we test the hypothesis that AQP1 inhibition impairs tumour growth in a mouse model of melanoma. After validating the inhibitor efficacy of two different AQP1 specific siRNAs in cell cultures, RNA interference experiments were performed by intratumoural injections of AQP1 siRNAs in mice. After 6 days of treatment, AQP1 siRNA treated tumours showed a 75 % reduction in volume when compared to controls. AQP1 protein level, in AQP1 knockdown tumours, was around 75 % that of the controls and was associated with a significant 40 % reduced expression of the endothelial marker, Factor VIII. Immunofluorescence analysis of AQP1 siRNA treated tumours showed a significantly lower microvessel density. Time course experiments demontrated that repeated injections of AQP1 siRNA over time are effective in sustaining the inhibition of tumour growth. Finally, we have confirmed the role of AQP1 in sustaining an active endothelium during angiogenesis and we have shown that AQP1 reduction causes an increase in VEGF levels. In conclusion, this study validates AQP1 as a pro-angiogenic protein, relevant for the therapy of cancer and other angiogenic-related diseases such as psoriasis, endometriosis, arthritis and atherosclerosis. 相似文献
997.
Iván Cosamalón-Gan Tatiana Cosamalón-Gan Giancarlo Mattos-Piaggio Vega Villar-Suárez José García-Cosamalón José Antonio Vega-Álvarez 《Neurocirugía (Asturias, Spain)》2021,32(1):21-35
Up until fairly recently, it was thought that sciatic pain in the lumbar herniated disc was caused by compression on the nerve root. However, the lumbar herniated disc shows mixed pictures which are difficult to explain by simple mechanical compromise. In recent years various immunology, immunohistochemistry and molecular biology studies have shown that the herniated tissue is not an inert material, but rather it Is biologically very active with the capability of expressing a series of inflammatory mediators: cytokines such as interleukin-1, interleukin-6, interleuquin-8 and tumor necrosis factor being the ones which stand out. The inflammation is not only induced by the chemical irritation of the bioactive substances released by the nucleus pulposus but also by an autoimmune response against itself. Thus, in addition to the mechanical factor, the biomechanical mediation plays an important role in the pathophysiology of sciatic pain and of radiculopathy. Through a review of a wide range of literature, we researched the cellular molecular mediators involved in this inflammatory process around the lumbar herniated disc and its involvement in sciatic pain. 相似文献
998.
Aurora Moreno Flores Luis Miguel Bernal-García Juan Pablo Sosa Cabezas María Hidalgo Llorca José Antonio Rodriguez Sanchez 《Neurocirugía (Asturias, Spain)》2021,32(2):89-93
Gangliogliomas are well-differentiated, slow-growing tumors. The majority are grade I of WHO. It appears predominantly in children and young adults. Most are located at the temporal lobe, and as symptomatology more frequent epileptic seizures of difficult pharmacological control. In general, they have a good prognosis after surgical resection. The anaplasic variant, considered to be grade III of the WHO, presents greater clinical and radiological aggressiveness. Leptomeningeal dissemination is exceptional in these types of tumors, but when diagnosed it presents a rapidly progressive and fatal course for the patient. 相似文献
999.
Pedro David Delgado López Beatriz Blanco de Val José Luis López Martínez Elena Araus Galdós Antonio Rodríguez Salazar 《Neurocirugía (Asturias, Spain)》2021,32(2):99-104
It is an increasingly common practice to indicate a carotid endarterectomy procedure based on the information provided by non-invasive tests like Duplex ultrasound, MR angiography or CT angiography, thereby obviating the performance of a conventional cerebral angiography. We present a case of symptomatic left carotid artery 80% stenosis in which cerebral angiography showed absence of the right A1 segment and bilateral anterior cerebral artery territories that filled only from a left injection. Just 90 seconds after carotid artery clamping at the neck, brain oximetry and somatosensory evoked potentials significantly dropped, that recovered after immediate clamp removal. Endarterectomy was dismissed and a carotid stent was successfully placed. This case highlights the importance of knowing the dynamics of cerebral blood circulation distal to the stenosis. If endarterectomy had been attempted, unawareness of the information provided by the cerebral angiography would have likely result in severe bi-hemispheric ischemia. 相似文献
1000.
Chiang Jannifer O. Azevedo Rafael S. Justino Maria C. A. Matos Haroldo J. Cabeça Hideraldo L. S. Silva Sandro P. Henriques Daniele F. Silva Eliana V. P. Andrade Gabriela S. S. Vasconcelos Pedro FC. Martins Lívia C. Azevedo Raimunda S. S. 《Journal of neurovirology》2021,27(4):626-630
Journal of NeuroVirology - We describe two neurological cases of Oropouche virus infection in northern Brazil, where the virus is endemic but neglected as a pathogen. This study reiterates the... 相似文献