Open Neuroimaging Journal最新文献

{"title":"Neuroimaging of non-human primates.","authors":"Timothy Q Duong","doi":"10.2174/1874440001105010146","DOIUrl":"https://doi.org/10.2174/1874440001105010146","url":null,"abstract":"Welcome to this special issue of the Open Neuroimaging Journal which focuses on neuroimaging studies of non-human primates (NHPs) as presented by leaders in the field. NHPs are important animal models because of their genetic, ontogenic, and physiological similarities to humans. Research using NHPs has significantly advanced our understanding of neuroscience, neurodegerative disorders, aging and development. NHP models have played a vital role in vaccine, AIDS and infectious disease research, among others. \u0000 \u0000Magnetic resonance imaging (MRI) has become a powerful research and clinical imaging tool because it can provide non-invasive anatomical, physiological and functional images at high spatial and temporal resolution with excellent soft tissue contrast. NHP studies benefit from the modern high-field MR scanners equipped with high performance gradients and multi-channel RF receivers and the innovative imaging and analysis tools. Because custom NHP scanners are not widely available, most NHP MRI studies are performed on human scanners. There are a few major changes for NHP studies and they include: i) cost and the availability of NHP resources, ii) expertise in handling NHPs and maintaining stable animal preparations, and iii) the need to achieve sufficient spatial resolution and signal-to-noise ratio for NHP brains which are much smaller than the human brains. Despite these challenges, there have been substantial progresses made and many of the knowledge gained have benefited human studies and vice versa. \u0000 \u0000This special issue describes some novel approaches and applications in the neuroimaging studies of NHPs. Darceuil and colleagues and Wey and colleagues describe the use of multimodal MRI to study ischemic stroke in the clinically relevant rhesus and baboon models. Chen and colleagues demonstrate how very high spatial resolution fMRI can be applied to study the topography of somatosensory cortex. Rane and Duong demonstrate that diffusion tensor imaging with long diffusion time improves fiber tracking in rhesus brains. Kochunov and Phillips describe development of corpus callosum during in-utero and postnatal maturation in baboons. Fedorov and colleagues show how atlas-guided segmentation can be used to calculate robust gray- and white-matter tissue maps in the velvet monkey brains. Dubowitz and colleagues develop a frameless stereotaxic localization strategy for NHP brains. And last but not least, Szabo and colleagues describe the MRI study of seizure-disorders in baboons. \u0000 \u0000I am grateful to all of the contributors to this special issue for their time and efforts.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"146"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257890/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30393117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-dependent cortical activation in voluntary muscle contraction.","authors":"Qi Yang,&nbsp;Xiaofeng Wang,&nbsp;Yin Fang,&nbsp;Vlodek Siemionow,&nbsp;Wanxiang Yao,&nbsp;Guang H Yue","doi":"10.2174/1874440001105010232","DOIUrl":"https://doi.org/10.2174/1874440001105010232","url":null,"abstract":"<p><p>This study was to characterize dynamic source strength changes estimated from high-density scalp electroencephalogram (EEG) at different phases of a submaximal voluntary muscle contraction. Eight healthy volunteers performed isometric handgrip contractions of the right arm at 20% maximal intensity. Signals of the handgrip force, electromyography (EMG) from the finger flexor and extensor muscles and 64-channel EEG were acquired simultaneously. Sources of the EEG were analyzed at 19 time points across preparation, execution and sustaining phases of the handgrip. A 3-layer boundary element model (BEM) based on the MNI (Montréal Neurological Institute) brain MRI was used to overlay the sources. A distributed current density model, LORETA L1 norm method was applied to the data that had been processed by independent component analysis (ICA). Statistical analysis based on a mixed-effects polynomial regression model showed a significant and consistent time-dependent non-linear source strength change pattern in different phases of the handgrip. The source strength increased at the preparation phase, peaked at the force onset time and decreased in the sustaining phase. There was no significant difference in the changing pattern of the source strength among Brodmann's areas 1, 2, 3, 4, and 6. These results show, for the first time, a high time resolution increasing-and-decreasing pattern of activation among the sensorimotor regions with the highest activity occurs at the muscle activity onset. The similarity in the source strength time courses among the cortical centers examined suggests a synchronized parallel function in controlling the motor activity.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"232-9"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e3/a8/TONIJ-5-232.PMC3256579.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30393484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional PET Evaluation of the Photosensitive Baboon.","authors":"C Ákos Szabó,&nbsp;Felipe S Salinas,&nbsp;Shalini Narayana","doi":"10.2174/1874440001105010206","DOIUrl":"https://doi.org/10.2174/1874440001105010206","url":null,"abstract":"<p><p>The baboon provides a unique, natural model of epilepsy in nonhuman primates. Additionally, photosensitivity of the epileptic baboon provides an important window into the mechanism of human idiopathic generalized epilepsies. In order to better understand the networks underlying this model, our group utilized functional positron emission tomography (PET) to compare cerebral blood flow (CBF) changes occurring during intermittent light stimulation (ILS) and rest between baboons photosensitive, epileptic (PS) and asymptomatic, control (CTL) animals. Our studies utilized subtraction and covariance analyses to evaluate CBF changes occurring during ILS across activation and resting states, but also evaluated CBF correlations with ketamine doses and interictal epileptic discharge (IED) rate during the resting state. Furthermore, our group also assessed the CBF responses related to variation of ILS in PS and CTL animals. CBF changes in the subtraction and covariance analyses reveal the physiological response and visual connectivity in CTL animals and pathophysiological networks underlying responses associated with the activation of ictal and interictal epileptic discharges in PS animals. The correlation with ketamine dose is essential to understanding differences in CBF responses between both groups, and correlations with IED rate provides an insight into an epileptic network independent of visual activation. Finally, the ILS frequency dependent changes can help develop a framework to study not only spatial connectivity but also the temporal sequence of regional activations and deactivations related to ILS. The maps generated by the CBF analyses will be used to target specific nodes in the epileptic network for electrophysiological evaluation using intracranial electrodes.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"206-15"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/40/17/TONIJ-5-206.PMC3257183.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30412446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Absolute oxygenation metabolism measurements using magnetic resonance imaging.","authors":"Hongyu An,&nbsp;Qingwei Liu,&nbsp;Cihat Eldeniz,&nbsp;Weili Lin","doi":"10.2174/1874440001105010120","DOIUrl":"https://doi.org/10.2174/1874440001105010120","url":null,"abstract":"<p><p>Cerebral oxygen metabolism plays a critical role in maintaining normal function of the brain. It is the primary energy source to sustain neuronal functions. Abnormalities in oxygen metabolism occur in various neuro-pathologic conditions such as ischemic stroke, cerebral trauma, cancer, Alzheimer's disease and shock. Therefore, the ability to quantitatively measure tissue oxygenation and oxygen metabolism is essential to the understanding of pathophysiology and treatment of various diseases. The focus of this review is to provide an introduction of various blood oxygenation level dependent (BOLD) contrast methods for absolute measurements of tissue oxygenation, including both magnitude and phase image based approaches. The advantages and disadvantages of each method are discussed.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"120-35"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/d7/9b/TONIJ-5-120.PMC3256581.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30412445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brain activation during autobiographical memory retrieval with special reference to default mode network.","authors":"Tadashi Ino,&nbsp;Ryusuke Nakai,&nbsp;Takashi Azuma,&nbsp;Toru Kimura,&nbsp;Hidenao Fukuyama","doi":"10.2174/1874440001105010014","DOIUrl":"https://doi.org/10.2174/1874440001105010014","url":null,"abstract":"<p><p>Recent neuroimaging studies have suggested that brain regions activated during retrieval of autobiographical memory (ABM) overlap with the default mode network (DMN), which shows greater activation during rest than cognitively demanding tasks and is considered to be involved in self-referential processing. However, detailed overlap and segregation between ABM and DMN remain unclear. This fMRI study focuses first on revealing components of the DMN which are related to ABM and those which are unrelated to ABM, and second on extracting the neural bases which are specifically devoted to ABM. Brain activities relative to rest during three tasks matched in task difficulty assessed by reaction time were investigated by fMRI; category cued recall from ABM, category cued recall from semantic memory, and number counting task. We delineated the overlap between the regions that showed less activation during semantic memory and number counting relative to rest, which correspond to the DMN, and the areas that showed greater or less activation during ABM relative to rest. ABM-specific activation was defined as the overlap between the contrast of ABM versus rest and the contrast of ABM versus semantic memory. The fMRI results showed that greater activation as well as less activation during ABM relative to rest overlapped considerably with the DMN, indicating that the DMN is segregated to the regions which are functionally related to ABM and the regions which are unrelated to ABM. ABM-specific activation was observed in the left-lateralized brain regions and most of them fell within the DMN.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"14-23"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/39/04/TONIJ-5-14.PMC3106359.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29915742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polyradiculopathies from schwannomatosis.","authors":"Yuxia Jia,&nbsp;James A Kraus,&nbsp;Hasini Reddy,&nbsp;Michael Groff,&nbsp;Eric T Wong","doi":"10.2174/1874440001105010009","DOIUrl":"https://doi.org/10.2174/1874440001105010009","url":null,"abstract":"<p><p>We describe a case of schwannomatosis presenting as radicular pain and numbness in multiple radicular nerve distributions. There were multiple peripheral nerve tumors detected by magnetic resonance imaging (MRI) at the left vestibular nerve, cauda equina, right radial nerve, thoracic paraspinal nerve, and brachial plexi. Several resected tumors have features of schwannomas, including hypercellular Antoni A areas, hypocellular Antoni B areas, Verocay bodies, and hyalinized blood vessels. The specimens are also positive for immunohistochemical staining for INI1 with diffuse nuclear staining. The findings are consistent with sporadic form of schwannomatosis. This case highlights the importance of using MRI and INI1 immunohistochemistry to differentiate familial schwannomatosis, neurofibromatosis 2 (NF2)-associated schwannomatosis, and sporadic schwannomatosis.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"9-13"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/0f/97/TONIJ-5-9.PMC3106375.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30218834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerebral Blood Volume Measurements - Gd_DTPA vs. VASO - and Their Relationship with Cerebral Blood Flow in Activated Human Visual Cortex.","authors":"Ai-Ling Lin,&nbsp;Hanzhang Lu,&nbsp;Peter T Fox,&nbsp;Timothy Q Duong","doi":"10.2174/1874440001105010090","DOIUrl":"https://doi.org/10.2174/1874440001105010090","url":null,"abstract":"<p><p>Measurements of task-induced changes in cerebral blood volume (CBV) have been demonstrated using VAscular Space Occupancy (VASO) techniques (noninvasive and newly developed) and a contrast agent-based (Gd- DTPA) method (invasive but well-established) with functional magnetic resonance imaging (fMRI). We compared the two methods in determining CBV changes during multi-frequency visual stimulation (4 and 8 Hz). Specifically, we aimed to assess the impact of repetition time (TR) on CBV changes determination using VASO. With additional measurements of cerebral blood flow (CBF), the flow-volume coupling relationship (α value) and cerebral metabolic rate of oxygen were further determined. The results showed that i) using VASO, short TR (2s) caused overestimation of CBV changes, while long TR (6s) generated consistent CBV results, by comparison to the GD-DTPA method; ii) overestimation of CBV changes caused underestimated CMRO(2) changes, but did not alter the frequency-related pattern, i.e., CMRO(2) changes at 4 Hz were greater than those at 8 Hz regardless of the TR; and iii) the tasked-induced CBF-CBV coupling was stimulus frequency-dependent, i.e., α = 0.35-0.38 at 4 Hz and α = 0.51-0.53 at 8 Hz. Our data demonstrated that, with carefully chosen TRs, CBV measurements can be achieved non-invasively with VASO techniques.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"90-5"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3245406/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30393115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A frameless stereotaxic MRI technique for macaque neuroscience studies.","authors":"David J Dubowitz,&nbsp;Miriam Scadeng","doi":"10.2174/1874440001105010198","DOIUrl":"https://doi.org/10.2174/1874440001105010198","url":null,"abstract":"<p><p>MRI has achieved widespread use for preplanning neuroscience procedures for non-human primate studies. However, orienting imaging studies in stereotaxic space has relied primarily on using a stereotaxic frame or co-registering fiducial markers with the neuroimaging. In this study, we present a simple approach in which the MRI dataset is aligned to the bony landmarks that define the Frankfurt stereotaxic baseline plane, without the need for a stereotaxic frame or additional external fiducials. To facilitate localizing the bony landmarks (infraorbital margin, external bony auditory meatus) on the MRI scans additional imaging landmarks (mid ocular plane, temporomandibular joint) are discussed that provide supplementary and readily visible points of reference. The frameless MRI stereotaxic technique was evaluated in 8 rhesus macaque monkeys using 3D fast gradient echo MRI images with 0.7mm isotropic resolution. 1) Difference in stereotaxic coordinates of fiducial markers was compared between a traditional stereotaxic frame and the frameless MRI technique (n=2). 2) Differences in stereotaxic coordinates for cerebral regions were compared between the frameless MRI technique and MRI obtained with the animal positioned in a MRI-compatible stereotaxic frame (n=4). 3) The frameless MRI technique was further refined to prescribe electrode penetrations within a dural recording chamber in stereotaxic coordinates relative to the electrode microdrive. Differences in MRI coordinates were compared with the electrode microdrive (n=3). Mean localization of fiducial markers differed by 1.6 +/- 0.6 mm between the frameless MRI technique and a traditional stereotaxic frame. Between the frameless technique and an MRI-compatible stereotaxic frame, localization of cerebral anatomy differed by 2.8 +/- 2.2 mm with the primary source of error being a pitch-up rotation in the sagittal plane. This localization difference was reduced to 0.5 +/- 0.6 mm when this rotation was removed. Frameless MRI coordinates for electrode tracts within the dural recording chamber were within 0.5mm +/- 0.2 mm of the electrode microdrive readings. This simple technique provides the ability to accurately plan surgery and neurophysiological recordings in an individual animal, and to define the location of cerebral anatomy and electrode or injection tracts using publically available software, and without the need for dedicated MRI-compatible localization hardware. The reduced need for deep anesthesia (a necessity with traditional stereotaxic frames) makes the technique more amenable for functional MRI studies. Since each animal provides the bony landmarks to define their own stereotaxic space, this technique is readily applicable to other species.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"198-205"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257065/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30393088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-field FMRI for human applications: an overview of spatial resolution and signal specificity.","authors":"Cheryl A Olman,&nbsp;Essa Yacoub","doi":"10.2174/1874440001105010074","DOIUrl":"https://doi.org/10.2174/1874440001105010074","url":null,"abstract":"<p><p>In the last decade, dozens of 7 Tesla scanners have been purchased or installed around the world, while 3 Tesla systems have become a standard. This increased interest in higher field strengths is driven by a demonstrated advantage of high fields for available signal-to-noise ratio (SNR) in the magnetic resonance signal. Functional imaging studies have additional advantages of increases in both the contrast and the spatial specificity of the susceptibility based BOLD signal. One use of this resultant increase in the contrast to noise ratio (CNR) for functional MRI studies at high field is increased image resolution. However, there are many factors to consider in predicting exactly what kind of resolution gains might be made at high fields, and what the opportunity costs might be. The first part of this article discusses both hardware and image quality considerations for higher resolution functional imaging. The second part draws distinctions between image resolution, spatial specificity, and functional specificity of the fMRI signals that can be acquired at high fields, suggesting practical limitations for attainable resolutions of fMRI experiments at a given field, given the current state of the art in imaging techniques. Finally, practical resolution limitations and pulse sequence options for studies in human subjects are considered.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"74-89"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/b1/71/TONIJ-5-74.PMC3245408.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30363159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Relationship Between M in \"Calibrated fMRI\" and the Physiologic Modulators of fMRI.","authors":"Hanzhang Lu,&nbsp;Joanna Hutchison,&nbsp;Feng Xu,&nbsp;Bart Rypma","doi":"10.2174/1874440001105010112","DOIUrl":"https://doi.org/10.2174/1874440001105010112","url":null,"abstract":"<p><p>The \"calibrated fMRI\" technique requires a hypercapnia calibration experiment in order to estimate the factor \"M\". It is desirable to be able to obtain the M value without the need of a gas challenge calibration. According to the analytical expression of M, it is a function of several baseline physiologic parameters, such as baseline venous oxygenation and CBF, both of which have recently been shown to be significant modulators of fMRI signal. Here we studied the relationship among hypercapnia-calibrated M, baseline venous oxygenation and CBF, and assessed the possibility of estimating M from the baseline physiologic parameters. It was found that baseline venous oxygenation and CBF are highly correlated (R(2)=0.77, P<0.0001) across subjects. However, the hypercapnia-calibrated M was not correlated with baseline venous oxygenation or CBF. The hypercapnia-calibrated M was not correlated with an estimation of M based on analytical expression either. The lack of correlation may be explained by the counteracting effect of venous oxygenation and CBF on the M factor, such that the actual M value of an individual may be mostly dependent on other parameters such as hematocrit. Potential biases in hypercapnia-based M estimation were also discussed in the context of possible reduction of CMRO(2) during hypercapnia.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"5 ","pages":"112-9"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263507/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30412444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}