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51.
52.
RT Krmar JR Ferraris SE Ruiz E Dibar AA Morandi JA Ramirez 《Canadian Metallurgical Quarterly》1997,11(4):502-503
The syndrome of inappropriate secretion of antidiuretic hormone (ADH) or SIADH has been reported in various disorders. We report a pediatric patient with nasopharynx carcinoma who may have developed a clinical SIADH with severe hyponatremia and generalized seizure during the administration of intravenous hydration. We propose that the inappropriately high plasma level of ADH led to the inability to excrete sufficient amounts of free water during a hyperhydration protocol with a relatively hypotonic fluid, which resulted in acute hyponatremia and central nervous system involvement. To avoid this complication, intravenous hydration before chemotherapy in children with nasopharynx carcinoma should be performed at a slower infusion rate and with a sodium chloride concentration of more than half isotonic. 相似文献
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Binary boundary maps are obtained by edge detection, then their relative translation is determined by conventional cross-correlation computed by the Fermat transform. Use of boundary maps emphasises edges and sharp discontinuities, while rejecting disturbances related to nonuniform illumination, thus avoiding the costly normalisation step. Use of integer arithmetic allows significant savings in computation 相似文献
55.
U Morandi A Stefani M Golinelli C Ruggiero L Brandi A Chiapponi C Santi R Lodi 《Canadian Metallurgical Quarterly》1997,11(3):432-439
Calcium release from the sarcoplasmic reticulum (SR) depending on depolarization of the transverse tubular membrane (TTM) caused by rapid ionic replacement was measured in skeletal muscle triadic vesicles using a stopped-flow apparatus and Fura-2, a membrane-impermeable Ca2+ indicator. Calcium release was triggered by an increase in the magnitude of depolarization. This Ca2+ release was inhibited by ruthenium red, digoxin and dantrolene, and enhanced by caffeine. Thus, Ca2+ release was found to occur through the SR Ca2+ release channel via TTM depolarization and to be able to cause skeletal muscle contraction. Calcium release curves could be divided into two phases. In contrast to other previous studies, in the fast phase the amount of released Ca2+ increased with an increase in the magnitude of depolarization but the Ca2+ release rate did not; on the other hand, in the slow phase the Ca2+ release rate increased but the amount of Ca2+ did not. Furthermore, the Ca2+ release rate was controlled by the luminal Ca2+ concentration of the SR only in the fast phase. These independent dual kinetics of Ca2+ release were explained by the calsequestrin regulation model. 相似文献
56.
Digital image registration using projections 总被引:3,自引:0,他引:3
Alliney S Morandi C 《IEEE transactions on pattern analysis and machine intelligence》1986,(2):222-233
In many application fields (e.g., aerospace and biomedical image processing), one has to deal with a sequence of images whose observation is made difficult by unpredictable relative movements of the camera and the scene. In order to obtain a stable display, the displacement of each image in the sequence with respect to one chosen as a reference must be preliminarily determined. This would usually require two-dimensional algorithms, involving a considerable computational effort. This work discusses a new algorithm for image registration, which requires only one-dimensional Fourier transformations. Preliminary experimental results are reported. 相似文献
57.
A miniature electrostatic element has been designed to selectively apply a 90 degrees phase shift to the unscattered beam in the back focal plane of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. The design involves a cylindrically shaped, biased-voltage electrode, which is surrounded by a concentric grounded electrode. Electrostatic calculations have been used to determine that the fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature size is greater than 5:1. Unlike the planar, three-electrode einzel lens originally proposed by Boersch for the same purpose, this new design does not require insulating layers to separate the biased and grounded electrodes, and it can thus be produced by a very simple microfabrication process. Scanning electron microscope images confirm that mechanically robust devices with feature sizes of approximately 1 microm can be easily fabricated. Preliminary experimental images demonstrate that these devices do apply a 90 degrees phase shift between the scattered and unscattered electrons, as expected. 相似文献
58.
Guido A. Zapata-Catzin Marcos Bonilla-Hernández Rossana F. Vargas-Coronado José M. Cervantes-Uc Humberto Vázquez-Torres Efrén Hernandez-Baltazar Lerma H. Chan-Chan Assunta Borzacchiello Juan V. Cauich-Rodríguez 《Journal of materials science. Materials in medicine》2018,29(10):161
Segmented polyurethanes were prepared with polycaprolactone diol as soft segment and various amounts of 4,4´-Methylenebis(cyclohexyl isocyanate) and atorvastatin, a statin used for lowering cholesterol, in order to obtain SPU with different content of rigid segments. Polyurethanes with 35% or 50% of rigid segment content were physicochemically characterized and their biocompatibility assessed with L929 fibroblasts. High concentrations of atorvastatin were incorporated by increasing the content of rigid segments as shown by FTIR, Raman, NMR, XPS and EDX. Thermal and mechanical characterization showed that polyurethanes containing atorvastatin and 35% of rigid segments were low modulus (13?MPa) semicrystalline polymers as they exhibited a glass transition temperature (Tg) at ?38?°C, melting temperature (Tm) at 46?°C and crystallinity close to 35.9% as determined by DSC. In agreement with this, X-ray diffraction showed reflections at 21.3° and 23.6° for PCL without reflections for atorvastatin suggesting its presence in amorphous form with higher potential bioavailability. Low content of rigid segments led to highly degradable polymer in acidic, alkaline and oxidative media with an acceptable fibroblast cytotoxicity up to 7 days possibly due to low atorvastatin content. 相似文献
59.
Ambra Costa Davide Ceresa Antonella De Palma Rossana Rossi Sara Turturo Sara Santamaria Carolina Balbi Federico Villa Daniele Reverberi Katia Cortese Pierangela De Biasio Dario Paladini Domenico Coviello Silvia Ravera Paolo Malatesta Pierluigi Mauri Rodolfo Quarto Sveva Bollini 《International journal of molecular sciences》2021,22(7)
We previously reported that c-KIT+ human amniotic-fluid derived stem cells obtained from leftover samples of routine II trimester prenatal diagnosis (fetal hAFS) are endowed with regenerative paracrine potential driving pro-survival, anti-fibrotic and proliferative effects. hAFS may also be isolated from III trimester clinical waste samples during scheduled C-sections (perinatal hAFS), thus offering a more easily accessible alternative when compared to fetal hAFS. Nonetheless, little is known about the paracrine profile of perinatal hAFS. Here we provide a detailed characterization of the hAFS total secretome (i.e., the entirety of soluble paracrine factors released by cells in the conditioned medium, hAFS-CM) and the extracellular vesicles (hAFS-EVs) within it, from II trimester fetal- versus III trimester perinatal cells. Fetal- and perinatal hAFS were characterized and subject to hypoxic preconditioning to enhance their paracrine potential. hAFS-CM and hAFS-EV formulations were analyzed for protein and chemokine/cytokine content, and the EV cargo was further investigated by RNA sequencing. The phenotype of fetal- and perinatal hAFS, along with their corresponding secretome formulations, overlapped; yet, fetal hAFS showed immature oxidative phosphorylation activity when compared to perinatal ones. The profiling of their paracrine cargo revealed some differences according to gestational stage and hypoxic preconditioning. Both cell sources provided formulations enriched with neurotrophic, immunomodulatory, anti-fibrotic and endothelial stimulating factors, and the immature fetal hAFS secretome was defined by a more pronounced pro-vasculogenic, regenerative, pro-resolving and anti-aging profile. Small RNA profiling showed microRNA enrichment in both fetal- and perinatal hAFS-EV cargo, with a stably- expressed pro-resolving core as a reference molecular signature. Here we confirm that hAFS represents an appealing source of regenerative paracrine factors; the selection of either fetal or perinatal hAFS secretome formulations for future paracrine therapy should be evaluated considering the specific clinical scenario. 相似文献