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101.
Hydroxyurea is a chemotherapeutic agent used for myeloproliferative disorders and sickle cell anemia that is well known to cause painful mucocutaneous ulcers, typically involving the legs or mouth. However, genital ulcerations due to hydroxyurea therapy are a rare, and likely underrecognized, adverse effect with only a few cases reported in the literature to date. Ulcers of the lower legs caused by hydroxyurea are associated with a diagnostic delay, and this is likely exacerbated in cases of genital ulceration due to a lack of awareness. Herein we present two cases of painful genital ulceration in patients on hydroxyurea therapy. In the first Case, an 87 year-old male with polycythemia vera developed an ulcer on the scrotum, which was assessed initially through virtual visits during the COVID-19 pandemic, and was refractory to topical and oral antibiotic treatments. The second case was a 79 year-old male with essential thrombocythemia and a history of persistent leg ulcers who developed erosions of the glans penis. Both patients experienced complete resolution within weeks of discontinuing hydroxyurea therapy. In conclusion, genital ulcers and erosions induced by hydroxyrea may be underrecognized in clinical practice, but if identified, withdrawal of hydroxyurea leads to quick resolution of these lesions and the associated pain. 相似文献
102.
Debra Rivera Irene Kalleveen Catalina Arteaga de Castro Hanneke van Laarhoven Dennis Klomp Wybe van der Kemp Jaap Stoker Aart Nederveen 《NMR in biomedicine》2020,33(4)
High field 31P spectroscopy has thus far been limited to diffuse liver disease. Unlike lower field‐strength scanners, there is no body coil in the bore of the 7 T and despite inadequate penetration depth (<10 cm), surface coils are the current state‐of‐the‐art for acquiring anatomical images to support multinuclear studies. We present a system of proton antennas and phosphorus loops for 31P spectroscopy and provide the first ultrahigh‐field phosphorus metabolic imaging of a tumor in the abdomen. Herein we characterize the degree to which antennas are isolated from underlying loops. Next, we evaluate the penetration depth of the two antennas available during multinuclear examinations. Finally, we combine phosphorus spectroscopy (two loops) with parallel transmit imaging (eight antennas) in a patient. The loops and antennas are inherently decoupled (no added circuitry, <0.1% power coupling). The penetration depth of two antennas gives twice that of conventional loops. The liver and full axial slice of the abdomen were imaged with eight transmit/receive antennas using parallel transmit B1‐shimming to overcome image voids. Phosphorus spectroscopy from a liver metastasis resolved individual peaks for phosphocholine and phosphoethenalomine. Proton antennas are inherently decoupled from phosphorus loops. By using two proton antennas it is possible to perform region‐of‐interest image‐based shimming in over 80% of the liver volume, thereby enabling phosphorus spectroscopy of localized disease. Shimming of the full extent of the abdominal cross‐section is feasible using a parallel transmit array of eight antennas. A system architecture capable of supporting eight‐channel parallel transmit and multinuclear spectroscopy is optimal for supporting multiparametric body imaging, including metabolic imaging, for monitoring the response of patients with liver metastases to cancer treatments and for patient risk stratification. In the meantime, the existing infrastructure using two antennas is sufficient for preliminary studies in metabolic imaging of tumors in the liver. 相似文献
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We describe a case of an intelligent, artistic 50-year-old woman with schizoaffective disorder with a long history of delusional preoccupation with laterality and episodes of reported shifts in handedness. Investigations including dichotic listening and lateralised visual imagery tasks indicated unusual patterns of asymmetry. Executive functions were found to be intact, and EEG and CT scan were normal. Interview schedules revealed high scores for schizotypy, and no evidence of a dissociative disorder, whereas psychotic symptoms with mood lability were evident on mental status examination. The subject's preoccupations are illustrated with a selection of her artistic productions. The case is discussed in the context of reports of a relationship between schizophrenia and ambiguous handedness. A cognitive neuropsychiatric formulation briefly explores the possibility of alternative cerebral hemispheres affecting cognitive-perceptual operations. 相似文献
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107.
Christopher M. Frost Daniel C. Ursu Shane M. Flattery Andrej Nedic Cheryl A. Hassett Jana D. Moon Patrick J. Buchanan R. Brent Gillespie Theodore A. Kung Stephen W. P. Kemp Paul S. Cederna Melanie G. Urbanchek 《Journal of neuroengineering and rehabilitation》2018,15(1):108
Introduction
Regenerative peripheral nerve interfaces (RPNIs) are biological constructs which amplify neural signals and have shown long-term stability in rat models. Real-time control of a neuroprosthesis in rat models has not yet been demonstrated. The purpose of this study was to: a) design and validate a system for translating electromyography (EMG) signals from an RPNI in a rat model into real-time control of a neuroprosthetic hand, and; b) use the system to demonstrate RPNI proportional neuroprosthesis control.Methods
Animals were randomly assigned to three experimental groups: (1) Control; (2) Denervated, and; (3) RPNI. In the RPNI group, the extensor digitorum longus (EDL) muscle was dissected free, denervated, transferred to the lateral thigh and neurotized with the residual end of the transected common peroneal nerve. Rats received tactile stimuli to the hind-limb via monofilaments, and electrodes were used to record EMG. Signals were filtered, rectified and integrated using a moving sample window. Processed EMG signals (iEMG) from RPNIs were validated against Control and Denervated group outputs.Results
Voluntary reflexive rat movements produced signaling that activated the prosthesis in both the Control and RPNI groups, but produced no activation in the Denervated group. Signal-to-Noise ratio between hind-limb movement and resting iEMG was 3.55 for Controls and 3.81 for RPNIs. Both Control and RPNI groups exhibited a logarithmic iEMG increase with increased monofilament pressure, allowing graded prosthetic hand speed control (R2?=?0.758 and R2?=?0.802, respectively).Conclusion
EMG signals were successfully acquired from RPNIs and translated into real-time neuroprosthetic control. Signal contamination from muscles adjacent to the RPNI was minimal. RPNI constructs provided reliable proportional prosthetic hand control.108.
Kyle A Kemp Nancy Chan Brandi McCormack Kathleen Douglas-England 《Health services research》2015,50(4):982-997
ObjectiveTo identify factors associated with patients’ overall rating of inpatient hospital care.ConclusionsOur results are novel in the Canadian population. Several questions for future research have been generated, in addition to opportunities for quality improvement within our own organization. 相似文献
109.
Ellia Mezgueldi Aurlia Bertholet‐Thomas Solange Milazzo Michael Morris Justine Bacchetta Nicole Fabien Pierre Cochat Anthony P. Weetman Elizabeth Helen Kemp Alexandre Belot 《Clinical Case Reports》2015,3(10):809-813
Early diagnosis of potentially life‐threatening autoimmune polyendocrinopathy‐candidiasis‐ectodermal dystrophy (APECED) is crucial, but is often delayed due to the clinical heterogeneity of the disorder. Even in the absence of the classic disease triad of chronic mucocutaneous candidiasis, hypoparathyroidism, and adrenocortical insufficiency, a diagnosis of APECED should be considered in children who have hypoparathyroidism and chronic keratitis, with a past medical history showing a mild and transient Candida infection. 相似文献
110.
van Rensburg Susan J. Hattingh Coenraad Johannes Clint Moremi Kelebogile E. Peeters Armand V. van Heerden Carel J. Erasmus Rajiv T. Zemlin Annalise E. Kemp Merlisa C. Jaftha Mariaan Khine Aye Aye Potocnik Felix C.V. Whati Lindiwe Engel-Hills Penelope van Toorn Ronald Kotze Maritha J. 《Metabolic brain disease》2021,36(6):1169-1181
Metabolic Brain Disease - In Part I of this Review we evaluated the scientific evidence for a Metabolic Model of multiple sclerosis (MS). Part II outlines the implementation of an adaptive... 相似文献