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Selective Aortic Arch Perfusion versus Open Cardiac Massage in Exsanguination Cardiac Arrest: A Comparison of Coronary Pressure Dynamics in Swine.

Resuscitation 2021 Apr 12. Epub 2021 Apr 12.

R Adams Cowley Shock Trauma Center, University of Maryland Medical System, Baltimore, MD, USA. Electronic address:

Aim: To evaluate the mean aortic-right atrial pressure (AoP-RAP) gradients and mean coronary perfusion pressures (CPPs) observed during open cardiac massage (OCM) versus those obtained with selective aortic arch perfusion (SAAP) in post-mortem hypovolemic swine.

Methods: Post-mortum, male swine, utilized in prior studies of hemorrhage, were included in the study. Animals were bled ∼ 25-50% of circulating volume prior to death. Read More

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Anthropometric, biochemical and hormonal profiles of the partially admixed pygmoid group in Rampasasa (Flores, Indonesia).

J Pediatr Endocrinol Metab 2021 Apr 12. Epub 2021 Apr 12.

Department of Pediatrics, Leiden University Medical Center, Leiden, Netherlands.

Objectives: We performed a cross-sectional study on anthropometric and laboratory characteristics of inhabitants of Rampasasa (Flores, Indonesia). Adults were categorised according to ancestry into three groups: pygmoid (P/P, offspring of pygmoid parents, n=8), mixed pygmoid (P/N, offspring of pygmoid and non-pygmoid parents, n=12) and non-pygmoid (N/N, n=10). Children (n=28) were P/N. Read More

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The microbiota of intertidal macroalgae Fucus distichus is site-specific and resistant to change following transplant.

Environ Microbiol 2021 Apr 5. Epub 2021 Apr 5.

Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.

It is unclear how host-associated microbial communities will be affected by future environmental change. Characterizing how microbiota differ across sites with varying environmental conditions and assessing the stability of the microbiota in response to abiotic variation are critical steps towards predicting outcomes of environmental change. Intertidal organisms are valuable study systems because they experience extreme variation in environmental conditions on tractable timescales such as tide cycles and across small spatial gradients in the intertidal zone. Read More

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Diversity and robustness of bone morphogenetic protein pattern formation.

Development 2021 Apr 1;148(7). Epub 2021 Apr 1.

Agricultural and Biological Engineering. Purdue University, West Lafayette, IN 47907, USA

Pattern formation by bone morphogenetic proteins (BMPs) demonstrates remarkable plasticity and utility in several contexts, such as early embryonic development, tissue patterning and the maintenance of stem cell niches. BMPs pattern tissues over many temporal and spatial scales: BMP gradients as short as 1-2 cell diameters maintain the stem cell niche of the germarium over a 24-h cycle, and BMP gradients of several hundred microns establish dorsal-ventral tissue specification in , zebrafish and embryos in timescales between 30 min and several hours. The mechanisms that shape BMP signaling gradients are also incredibly diverse. Read More

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Disrupted eye and head development in rainbow trout with reduced ultraviolet (sws1) opsin expression.

J Comp Neurol 2021 Mar 28. Epub 2021 Mar 28.

Department of Marine Biosciences, Tokyo University of Marine Science and Technology, Tokyo, Japan.

Visual opsins are proteins expressed by retinal photoreceptors that capture light to begin the process of phototransduction. In vertebrates, the two types of photoreceptors (rods and cones) express one or multiple opsins and are distributed in variable patterns across the retina. Some cones form opsin retinal gradients, as in the mouse, whereas others form more demarcated opsin domains, as in the lattice-like mosaic retinas of teleost fishes. Read More

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The fate of plastic litter within estuarine compartments: An overview of current knowledge for the transboundary issue to guide future assessments.

Environ Pollut 2021 Mar 15;279:116908. Epub 2021 Mar 15.

Laboratório de Microcontaminantes Orgânicos e Ecotoxicologia Aquática - Instituto de Oceanografia - Universidade Federal do Rio Grande (FURG). Av. Itália, Km 8, Carreiros, CEP: 96203-900, Rio Grande, RS, Brazil.

Plastics can enter biogeochemical cycles and thus be found in most ecosystems. Most studies emphasize plastic pollution in oceanic ecosystems even though rivers and estuaries are acknowledged as the main sources of plastics to the oceans. This review detected few studies approaching the transboundary issue, as well as patterns of estuarine gradients in predicting plastic distribution and accumulation in water, sediments, and organisms. Read More

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Ultra-fast proteomics with Scanning SWATH.

Nat Biotechnol 2021 Mar 25. Epub 2021 Mar 25.

Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, UK.

Accurate quantification of the proteome remains challenging for large sample series and longitudinal experiments. We report a data-independent acquisition method, Scanning SWATH, that accelerates mass spectrometric (MS) duty cycles, yielding quantitative proteomes in combination with short gradients and high-flow (800 µl min) chromatography. Exploiting a continuous movement of the precursor isolation window to assign precursor masses to tandem mass spectrometry (MS/MS) fragment traces, Scanning SWATH increases precursor identifications by ~70% compared to conventional data-independent acquisition (DIA) methods on 0. Read More

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Cell-type identity of the avian cochlea.

Cell Rep 2021 Mar;34(12):108900

Department of Otolaryngology - Head & Neck Surgery, Institute for Stem Cell Biology & Regenerative Medicine, Stanford University School of Medicine, Palo Alto, CA 94305, USA. Electronic address:

In contrast to mammals, birds recover naturally from acquired hearing loss, which makes them an ideal model for inner ear regeneration research. Here, we present a validated single-cell RNA sequencing resource of the avian cochlea. We describe specific markers for three distinct types of sensory hair cells, including a previously unknown subgroup, which we call superior tall hair cells. Read More

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The impact of reducing the femoral stem length in total hip arthroplasty during gait.

Arch Orthop Trauma Surg 2021 Mar 24. Epub 2021 Mar 24.

MSK Lab, Imperial College London, Michael Uren Hub, 2nd Floor, White City Campus, Wood Lane, London, W12 0BZ, UK.

Aim: The length of the femoral stem in total hip arthroplasty (THA) is a practical consideration to prevent gait impairment. The aim of this study was to determine if reducing the femoral stem length in THA would lead to impaired gait biomechanics.

Methods: Patients uniformly with the same brand implant of differing lengths (100 mm vs 140-166 mm) were taken retrospectively from a prospective trial introducing a new short stem. Read More

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Distinct features of the Leishmania cap-binding protein LeishIF4E2 revealed by CRISPR-Cas9 mediated hemizygous deletion.

PLoS Negl Trop Dis 2021 Mar 24;15(3):e0008352. Epub 2021 Mar 24.

Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.

Leishmania parasites cycle between sand-fly vectors and mammalian hosts adapting to alternating environments by stage-differentiation accompanied by changes in the proteome profiles. Translation regulation plays a central role in driving the differential program of gene expression since control of gene regulation in Leishmania is mostly post-transcriptional. The Leishmania genome encodes six eIF4E paralogs, some of which bind a dedicated eIF4G candidate, and each eIF4E is assumed to have specific functions with perhaps some overlaps. Read More

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Dynamic Heterogeneity of Filler-Associated Interphases in Polymer Nanocomposites.

Macromol Rapid Commun 2021 Mar 24:e2100061. Epub 2021 Mar 24.

Institut für Physik-NMR, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 7, Halle, 06120, Germany.

Dynamically inhomogeneous polymer systems exhibit interphases with mobility gradients. These are believed to play key roles in the material's performance. A prominent example is particle-filled rubber, a special case of a crosslinked polymer nanocomposite, where favorable rubber-filler interactions may give rise to a nanoscale immobilized layer around the filler, including regions of intermediate mobility. Read More

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Ultrashort echo time Cones double echo steady state (UTE-Cones-DESS) for rapid morphological imaging of short T tissues.

Magn Reson Med 2021 Mar 23. Epub 2021 Mar 23.

Department of Radiology, University of California, San Diego, San Diego, CA, USA.

Purpose: In this study, we aimed to develop a new technique, ultrashort echo time Cones double echo steady state (UTE-Cones-DESS), for highly efficient morphological imaging of musculoskeletal tissues with short T s. We also proposed a novel, single-point Dixon (spDixon)-based approach for fat suppression.

Methods: The UTE-Cones-DESS sequence was implemented on a 3T MR system. Read More

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Patterning Neuroepithelial Cell Sheet a Sustained Chemical Gradient Generated by Localized Passive Diffusion Devices.

ACS Biomater Sci Eng 2021 04 22;7(4):1713-1721. Epub 2021 Mar 22.

Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States.

Recent advances in human pluripotent stem cells (hPSCs)-derived models open a new avenue for studying early stage human development. While current approaches leverage the self-organizing capability of hPSCs, it remains unclear whether extrinsic morphogen gradients are sufficient to pattern neuroectoderm tissues . While microfluidics or hydrogel-based approaches to generate chemical gradients are well-established, these systems either require continuous pumping or encapsulating cells in gels, making it difficult for adaptation in standard biology laboratories and downstream analysis. Read More

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Ecological and Metabolic Thresholds in the Bacterial, Protist, and Fungal Microbiome of Ephemeral Saline Lakes (Monegros Desert, Spain).

Microb Ecol 2021 Mar 16. Epub 2021 Mar 16.

Integrative Freshwater Ecology Group, Centro de Estudios Avanzados de Blanes (CEAB-CSIC), Acces Cala Sant Francesc 14, 17300, Blanes, Spain.

We studied the 16S and 18S rRNA genes of the bacterial, protist, and fungal microbiomes of 131 samples collected in 14 ephemeral small inland lakes located in the endorheic area of the Monegros Desert (NE Spain). The sampling covered different temporal flooding/desiccation cycles that created natural salinity gradients between 0.1% (w/v) and salt saturation. Read More

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Total Retention Liquid Chromatography-Mass Spectrometry to Achieve Maximum Protein Sequence Coverage.

Anal Chem 2021 03 16;93(12):5054-5060. Epub 2021 Mar 16.

Peptide identification by liquid chromatography-mass spectrometry (LC-MS) requires retention and elution of peptides from the LC column. Although medium and hydrophobic peptides are readily retained by the C18 columns that are commonly used in proteomics, short and hydrophilic peptides are not retained nor measured by MS due to their elution in the void volume after sample injection. These nonretained peptides can possess important post-translational modifications, such as glycosylation or phosphorylation. Read More

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Efficacy of TIPS Reduction for Refractory Hepatic Encephalopathy, Right Heart Failure, and Liver Dysfunction.

AJR Am J Roentgenol 2021 03 11:1-6. Epub 2021 Mar 11.

Department of Radiology, Division of Vascular and Interventional Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, WCC 308-B, 1 Deaconess Rd, Boston, MA 02215.

The purpose of this study was to determine clinical outcomes of patients undergoing TIPS reduction. In this institutional review board-approved, HIPAA-compliant study, all TIPS reductions performed at two institutions from January 1, 2008 to January 31, 2016, were retrospectively identified. Patients were divided into two groups according to pre-TIPS symptoms: volume overload due to ascites or hydrothorax (VO; = 14) or variceal bleeding (VB; = 12). Read More

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System-Wide Profiling of Protein Complexes Via Size Exclusion Chromatography-Mass Spectrometry (SEC-MS).

Methods Mol Biol 2021 ;2259:269-294

Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Zürich, Switzerland.

In living cells, most proteins are organized in stable or transient functional assemblies, protein complexes, which control a multitude of vital cellular processes such as cell cycle progression, metabolism, and signal transduction. Over several decades, specific protein complexes have been analyzed by structural biology methods, initially X-ray crystallography and more recently single particle cryoEM. In parallel, mass spectrometry (MS)-based methods including in vitro affinity-purification coupled to MS or in vivo protein proximity-dependent labeling methods have proven particularly effective to detect complexes, thus nominating new assemblies for structural analysis. Read More

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Responses of Runoff and Soil Loss to Rainfall Regimes and Soil Conservation Measures on Cultivated Slopes in a Hilly Region of Northern China.

Authors:
Haiyan Fang

Int J Environ Res Public Health 2021 Feb 21;18(4). Epub 2021 Feb 21.

Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.

Cultivated land plays an important role in water and soil loss in earthy/rocky mountainous regions in northern China, however, its response to soil conservation measures and rainfall characteristics are still not fully understood. In the present study, 85 erosive rainfall events in 2011-2019 were grouped into three types, and the responses of runoff and soil loss to soil conservation measures and rainfall regimes on five cultivated plots with different slopes in the upstream catchment of the Miyun Reservoir were evaluated. Results found that mean event runoff depths and soil loss rates on the five plots ranged from 0. Read More

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February 2021

Research Supporting a Pilot Study of Metronomic Dapsone during Glioblastoma Chemoirradiation.

Authors:
Richard E Kast

Med Sci (Basel) 2021 Feb 16;9(1). Epub 2021 Feb 16.

IIAIGC Study Center, Burlington, VT 05408, USA.

This short note presents previous research data supporting a pilot study of metronomic dapsone during the entire course of glioblastoma treatment. The reviewed data indicate that neutrophils are an integral part of human glioblastoma pathophysiology, contributing to or facilitating glioblastoma growth and treatment resistance. Neutrophils collect within glioblastoma by chemotaxis along several chemokine/cytokine gradients, prominently among which is interleukin-8. Read More

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February 2021

Evaluating the Short-Term Clinical Efficacy of Magnetic Resonance Elastography in Patients with Budd-Chiari Syndrome.

Acad Radiol 2021 Mar 2. Epub 2021 Mar 2.

Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, China. Electronic address:

Rationale And Objectives: To investigate the clinical relevance of liver stiffness (LS) in evaluating liver function properties in patients with Budd-Chiari syndrome (BCS) with different severities and LS variation before and after endovascular intervention.

Materials And Methods: Between December 2016 and March 2019, patients with a diagnosis of BCS were considered for enrollment consecutively in our study. Liver function of these patients was classified according to Child-Pugh grading standard before treatment. Read More

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The Rate of Apparent Diffusion Coefficient Change With Diffusion Time on Breast Diffusion-Weighted Imaging Depends on Breast Tumor Types and Molecular Prognostic Biomarker Expression.

Invest Radiol 2021 Mar 5. Epub 2021 Mar 5.

From the Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine Department of Clinical Innovative Medicine, Institute for Advancement of Clinical and Translational Science, Kyoto University Hospital National Hospital Organisation, Kyoto Medical Center Kyoto-Katsura Hospital Department of Biomedical Statistics and Bioinformatics, Kyoto University Graduate School of Medicine, Kyoto, Japan Siemens Healthcare K.K., Tokyo, Japan Siemens Healthcare GmbH, Erlangen, Germany Department of Breast Surgery, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan.

Introduction: The aim of this study was to investigate the variation of apparent diffusion coefficient (ADC) values with diffusion time according to breast tumor type and prognostic biomarkers expression.

Materials And Methods: A total of 201 patients with known or suspected breast tumors were prospectively enrolled in this study, and 132 breast tumors (86 malignant and 46 benign) were analyzed. Diffusion-weighted imaging scans with 2 diffusion times were acquired on a clinical 3-T magnetic resonance imaging scanner using oscillating and pulsed diffusion-encoding gradients (effective diffusion times, 4. Read More

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Joint image and field map estimation for multi-echo hyperpolarized C metabolic imaging of the heart.

Magn Reson Med 2021 Jul 3;86(1):258-276. Epub 2021 Mar 3.

Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland.

Purpose: Image reconstruction of metabolic images from hyperpolarized C multi-echo data acquisition is sensitive to susceptibility-induced phase offsets, which are particularly challenging in the heart. A model-based framework for joint estimation of metabolite images and field map from echo shift-encoded data is proposed. Using simulations, it is demonstrated that correction of signal spilling due to incorrect decomposition of metabolites and geometrical distortions over a wide range of off-resonance gradients is possible. Read More

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lncLocator 2.0: a cell-line-specific subcellular localization predictor for long non-coding RNAs with interpretable deep learning.

Bioinformatics 2021 Feb 25. Epub 2021 Feb 25.

Department of Automation, Institute of Image Processing and Pattern Recognition, Shanghai Jiao Tong University, Shanghai, 200240, China.

Motivation: Long non-coding RNAs (lncRNAs) are generally expressed in a tissue-specific way, and subcellular localizations of lncRNAs depend on the tissues or cell lines that they are expressed. Previous computational methods for predicting subcellular localizations of lncRNAs do not take this characteristic into account, they train a unified machine learning model for pooled lncRNAs from all available cell lines. It is of importance to develop a cell-line-specific computational method to predict lncRNA locations in different cell lines. Read More

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February 2021

Shifts in the relative fitness contributions of fecundity and survival in variable and changing environments.

J Exp Biol 2021 Feb 24;224(Pt Suppl 1). Epub 2021 Feb 24.

Department of Integrative Biology, University of California, Berkeley, CA 94720-3140, USA.

Organisms respond to shifts in climate means and variability via distinct mechanisms. Accounting for these differential responses and appropriately aggregating them is central to understanding and predicting responses to climate variability and change. Separately considering fitness components can clarify organismal responses: fecundity is primarily an integrated, additive response to chronic environmental conditions over time via mechanisms such as energy use and acquisition, whereas survival can be strongly influenced by short-term, extreme environmental conditions. Read More

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February 2021

Temperature thresholds of ecosystem respiration at a global scale.

Nat Ecol Evol 2021 04 22;5(4):487-494. Epub 2021 Feb 22.

School of Biological Sciences, University of Reading, Reading, UK.

Ecosystem respiration is a major component of the global terrestrial carbon cycle and is strongly influenced by temperature. The global extent of the temperature-ecosystem respiration relationship, however, has not been fully explored. Here, we test linear and threshold models of ecosystem respiration across 210 globally distributed eddy covariance sites over an extensive temperature range. Read More

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Bus commuter exposure and the impact of switching from diesel to biodiesel for routes of complex urban geometry.

Environ Pollut 2020 Aug 17;263(Pt A):114601. Epub 2020 Apr 17.

Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, 86036-370, Londrina, PR, Brazil.

We report on commuters' exposure to black carbon (BC), PM and particle number (PN, with aerodynamic diameter, d, in the range 0.01 Read More

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Spatial dependency and the role of local susceptibility for velocity selective arterial spin labeling (VS-ASL) relative tagging efficiency using accelerated 3D radial sampling with a BIR-8 preparation.

Magn Reson Med 2021 Jul 21;86(1):293-307. Epub 2021 Feb 21.

Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.

Purpose: Velocity selective arterial spin labeling (VS-ASL) is a promising approach for non-contrast perfusion imaging that provides robustness to vascular geometry and transit times; however, VS-ASL assumes spatially uniform tagging efficiency. This work presents a mapping approach to investigate VS-ASL relative tagging efficiency including the impact of local susceptibility effects on a BIR-8 preparation.

Methods: Numerical simulations of tagging efficiency were performed to evaluate sensitivity to regionally varying local susceptibility gradients and blood velocity. Read More

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Complex Human Action Recognition Using a Hierarchical Feature Reduction and Deep Learning-Based Method.

SN Comput Sci 2021 13;2(2):94. Epub 2021 Feb 13.

University of Leeds, Institute for Transport Studies, 34-40 University Road, Leeds, LS2 9JT UK.

Automated human action recognition is one of the most attractive and practical research fields in computer vision. In such systems, the human action labelling is based on the appearance and patterns of the motions in the video sequences; however, majority of the existing research and most of the conventional methodologies and classic neural networks either neglect or are not able to use temporal information for action recognition prediction in a video sequence. On the other hand, the computational cost of a proper and accurate human action recognition is high. Read More

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February 2021

An x-ray microanalytical method for measuring in vivo element and water concentrations, relating to osmoregulation, in cells and tissues of the posterior eye.

J Microsc 2021 Feb 19. Epub 2021 Feb 19.

Department of Psychology and Counselling, La Trobe University, Melbourne, Victoria, Australia.

Osmoregulation is critical for cell and tissue survival yet there are relatively few methods available to determine osmotic gradients from water and elemental concentration either in single cells or across multiple cellular layers of tissue. X-ray microanalysis of frozen-hydrated preparations in a scanning electron microscope is one such powerful, sensitive, nondestructive technique. Here we use x-ray microanalysis to quantitatively analyse intracellular element concentrations and oxygen concentrations, as a proxy for water concentrations, in selected individual cells of the posterior eye. Read More

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February 2021

Model Analysis of Post-Stimulation Effect on Axonal Conduction and Block.

IEEE Trans Biomed Eng 2021 Feb 5;PP. Epub 2021 Feb 5.

Objective: To reveal the possible contribution of changes in membrane ion concentration gradients and ion pump activity to axonal conduction/block induced by long-duration electrical stimulation.

Methods: A new model for conduction and block of unmyelinated axons based on the classical Hodgkin-Huxley (HH) equations is developed to include changes in Na+ and K+ concentrations and ion pumps. The effects of long-duration stimulation on axonal conduction/block is analyzed by computer simulation using this new model. Read More

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February 2021