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81.
The perception of causal relationships is crucial to understanding and interacting with our physical and social environment. However, whether the same or different neural processes are involved in perceiving physical and social causality is unknown. Therefore, this study is focused on commonalities and differences in the neural correlates of causality perception in both contexts. During fMRI data-acquisition, participants judged causal relationships of objects in two types of animated video clips (physical/social) with similar manipulations of temporal and spatial stimulus characteristics. Four conditions were analyzed in a two-factorial design [physical causal (PC), physical non-causal (PNC), social causal (SC), social non-causal (SNC)]. We found that higher angles and longer time delays led to decreasing judgments of causality in the physical context, whereas the same manipulations led to increasing judgments in the social context. Instead of a common network for causal judgments (PC>PNC∩SC>SNC), we found a reversed activation pattern for the factors context and judgment. PC and SNC [(PC>PNC)>(SC>SNC)] produced activations in the bilateral insula, the right angular and inferior frontal gyrus and the medial supplementary motor area. PNC and SC [(PC>PNC)<(SC>SNC)] produced activity in medial frontal, left superior temporal and anterior cingulate brain regions. Our data suggest, that the same brain regions contribute to the impression of physical and social causality. However, they demonstrate a reversed activation pattern that reflects the stimulus characteristics of the respective conditions. Thus, specific stimulus characteristics are crucial for the perception of causality. 相似文献
82.
Metaphors are fundamental to creative thought and expression. Newly coined metaphors regularly infiltrate our collective vocabulary and gradually become familiar, but it is unclear how this shift from novel to conventionalized meaning happens in the brain. We investigated the neural career of metaphors in a functional magnetic resonance imaging study using extensively normed new metaphors and simulated the ordinary, gradual experience of metaphor conventionalization by manipulating participants' exposure to these metaphors. Results showed that the conventionalization of novel metaphors specifically tunes activity within bilateral inferior prefrontal cortex, left posterior middle temporal gyrus, and right postero-lateral occipital cortex. These results support theoretical accounts attributing a role for the right hemisphere in processing novel, low salience figurative meanings, but also show that conventionalization of metaphoric meaning is a bilaterally-mediated process. Metaphor conventionalization entails a decreased neural load within semantic networks rather than a hemispheric or regional shift across brain areas. 相似文献
83.
Talukdar AJ Ashokkumar C Wilson P Gupta A Sun Q Boig L Abu-Elmagd K Mazariegos G Green M Sindhi R 《Pediatric transplantation》2009,13(3):353-359
Abstract: Multiple measurements (n = 212) of lymphocyte subsets in 67 children treated with steroid-free Tacrolimus, and rabbit anti-human thymocyte globulin induction demonstrate early reconstitution of T-cytotoxic and NK cells. Reconstitution of CD4+ cells is complete after the second post-transplant year. During the period at risk for rejection, NK and T-cytotoxic cell counts are significantly higher among Rejectors. During periods at increased risk for EBV viral infection, CD4 counts bear a significant inverse relationship to EBV viral load in a subset of at-risk recipients. Rejection-prone children also demonstrate significantly higher counts of total lymphocytes, Tc and NK cells prior to SBTx, and may illustrate one basis for enhanced baseline immunocompetence. 相似文献
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Suman Saha Sambrita Majumder Sushovan Das Tapan Kumar Das Anjan Bhattacharyya Sankhajit Roy 《Bulletin of environmental contamination and toxicology》2018,100(4):548-552
A laboratory experiment was conducted to investigate the effect of pH on the persistence and the dissipation of the new readymix formulation of bispyribac sodium and metamifop. The experiment was conducted in water of three different pH viz. 4.0, 7.0 and 9.2. The spiking level of both the compounds in water was 1.0 and 2.0 µg/mL. The residues were extracted by a simple, quick and reliable method and quantified by liquid chromatography tandem mass spectrometry (LC–MS/MS). The method was justified based on the recovery study, which was >?85%. The dissipation of both compounds followed first order kinetics. The half-life values ranged between 19.86–36.29 and 9.92–19.69 days for bispyribac sodium and metamifop, respectively. The pH of water has a prominent effect on degradation of both the compounds. The rate of dissipation of both the compounds was highest in water of acidic pH followed by neutral and alkaline pH. 相似文献
86.
Koro following cannabis smoking: two case reports 总被引:1,自引:1,他引:0
Koro in the background of drug abuse is quite rare. The present report of Koro during the first experience with cannabis is the only account of its kind in the world Koro literature to date. The nature and extent of this genital depersonalization is discussed. 相似文献
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Mrinal Kumar Das Rakesh Arya Sanjita Debnath Rahul Debnath Anindita Lodh Subasa Chandra Bishwal Anjan Das Ranjan Kumar Nanda 《Antimicrobial agents and chemotherapy》2016,60(4):2257-2264
Population level variation of drug metabolism phenotype (DMP) has great implications in treatment outcome, drug-related side effects, and resistance development. In this study, we used a gas chromatography-time of flight-mass spectrometry (GC-TOF-MS)-based untargeted urine metabolomics approach to understand the DMP of a tuberculosis (TB) patient cohort (n = 20) from Tripura, a state in the northeastern part of India. Urine samples collected at different postdose time points (2 h, 6 h, 12 h, 24 h, 36 h, and 48 h) from these newly diagnosed TB patients receiving first-line anti-TB drugs were analyzed, and we have successfully detected three of the four first-line drugs, viz., isoniazid (INH), ethambutol (ETB), and pyrazinamide (PZA). The majority of their known metabolites, acetyl-isoniazid (AcINH), isonicotinic acid (INA), isonicotinuric acid (INTA), 2,2′-(ethylenediimino)-dibutyric acid (EDBA), 5-hydroxypyrazinamide (5OH-PZA), pyrazinoic acid (POA), and 5-hydroxypyrazinoic acid (5OH-POA), were also detected. Analyzing the variation in abundances of drugs and their known metabolites and calculating the metabolic ratios in these samples, we offer comprehensive DMP information on this small patient cohort that represents Tripura, India. The majority (75%) of these patients are found to be slow acetylators of INH. The average metabolic ratios of POA/PZA and 5OH-POA/POA are 3.16 ± 3.03 and 6.09 ± 6.15, respectively. Employing correlation analysis of the metabolomics metadata and a manual prediction of drug catabolism, we have proposed 2-aminobutyric acid (AABA) as a novel metabolite of ETB. These observations indicate the usefulness of GC-MS-based metabolomics to characterize the DMP at a population level and also to identify novel drug metabolites. 相似文献
90.
Sukhendu Kumar Pramanik Surajit Dutta Anjan Bhattacharyya 《Bulletin of environmental contamination and toxicology》2009,82(5):644-646
Multilocational field trials were conducted in grapevines at four different locations by applying hydrogen cyanamide 50% SL
during 2006–2007. In order to determine the residue of hydrogen cyanamide in grape, hydrogen cyanamide 50% SL was applied
to the freshly pruned grapevines at the rate of 1.20% a.i./L, 2.40% a.i./L, 4.80% a.i./L along with untreated control. No
residue was detected in grape berries at the time of harvest irrespective of any locations. 相似文献