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51.
In this work, a colorimetric approach for the detection of ascorbic acid (AA) and thyroxine (TH) was developed by synthesizing cost-effective silver nanoparticles (AgNPs) decorated with epigallocatechin gallate (EGCG) and CTAB. EGCG is the major bioactive chemical constituent that played a significant role in this study. The environment around the nanoparticle (NP) was controlled by adding CTAB surfactants. The synthesized NPs were characterized by different advanced techniques including XRD, XPS, SEM, and TEM. UV-visible spectra were thoroughly analyzed for sensing of AA and TH and the colour change of the solution can be visually monitored. The change in the localized surface plasmon resonance (LSPR) properties was used as an asset for the detection of AA and TH. A good linear relationship was obtained in both the sensing schemes with a limit of detection (LoD) of 0.67 μM and 0.33 μM for AA and TH respectively. Furthermore, the nanoparticles (NP) were implemented for real-sample analysis (pharmaceutical tablets). A cost-effective filter paper strip-based method coupled with smartphone scanning sensing was developed for the detection of AA. The interaction of AA and TH with the probe was depicted by a density functional theory (DFT) analysis. The synthesized NPs show tremendous selectivity towards AA and TH and excellent potential for practical applications.

In this work, a colorimetric approach for the detection of ascorbic acid and thyroxine was developed by synthesizing cost-effective silver nanoparticles (AgNPs) decorated with epigallocatechin gallate (EGCG) and CTAB.  相似文献   
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Correction for ‘Realization of multi-configurable logic gate behaviour on fluorescence switching signalling of naphthalene diimide congeners’ by Hridoy Jyoti Bora et al., RSC Adv., 2021, 11, 35274–35279. DOI: 10.1039/d1ra06728a.

The authors regret that there was an error in the sentence in lines 24–27 in the left column on page 35278 of the original article. The text originally read, “Mass spectrometric data Shimadzu UV-Vis spectrophotometer, UV-2600 is used to record the absorption spectra were gained from a THERMO 3000 Exactive Plus Orbitrap Mass Spectrometer”. This sentence should read, “Mass spectrometric data were gained from a THERMO 3000 Exactive Plus Orbitrap Mass Spectrometer. Shimadzu UV-Vis spectrophotometer, UV-2600 is used to record the absorption spectra”.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
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Three glutamic acid analogues, N-methyl-D-aspartic (NMDA), quisqualic (QQ), and kainic (KAI) acids were applied topically to the ventral surface of the medulla (VMS) in paralyzed, vagotomized and carotid sinus denervated cats hyperventilated to apnea. Respiratory and vasomotor effects were assessed by changes in phrenic nerve activity and systemic arterial blood pressure. All three agents to varying degrees raised systemic blood pressure, but only NMDA consistently initiated phrenic nerve activity at pCO2 levels below that observed in control trials. KAI and QQ raised blood pressure even in those animals in which they had little effect on initiating phrenic nerve activity. Furthermore, respiratory responses were obtained from localized areas on VMS, namely the intermedio-caudal zone (I-C areas); whereas blood pressure elevations could be obtained from wider VMS areas including the rostral zone (R areas). In addition, the effects of the three amino acids on blood pressure were quantitatively different with KAI causing much greater increases in blood pressure than QQ or NMDA. The respiratory and vasomotor effects of NMDA and QQ were blocked by the use of 2-amino-5-phosphonovaleric acid and L-glutamic acid diethylester, their respective antagonists. The results suggest that neurons in the VMS which cause respiratory and vasomotor responses are not identical. Cells containing receptors stimulated by NMDA predominantly increase respiration, whereas cells containing receptors excited by KAI are more effective in eliciting vasomotor responses.  相似文献   
54.
Halpin RJ  Bendok BR  Sato KT  Liu JC  Patel JD  Rosen ST 《Surgical neurology》2005,63(5):469-74; discussion 474-5
BACKGROUND: We describe a case of vertebral metastases treated with a combination of percutaneous radiofrequency ablation (RFA) and vertebroplasty in a single session. CASE DESCRIPTION: A 45-year-old female with recently diagnosed metastatic non-small cell lung cancer was referred for consideration of vertebroplasty after having several weeks of back pain. Computed tomography and magnetic resonance imaging scans of the thoracic spine revealed metastatic lesions at the T9 and T12 bodies. Radiofrequency ablation was performed using a starburst array electrode (Rita Medical Systems, Mountain View, Calif). The metastatic lesion in the T9 vertebral body measured 1.5 x 1.5 cm and was heated to 100 degrees C for 5 minutes. Vertebroplasty was then performed on this lesion as well as a lesion at T12 with no complications. The patient was discharged home the same day without complaints. CONCLUSION: Radiofrequency ablation and vertebroplasty are minimally invasive procedures that can be used in combination to treat spinal metastases. The pain relief from these treatments is often immediate. RFA can also be used to minimize procedure-related complications during the vertebroplasty. In properly selected patients, RFA may also increase the duration of local spinal stabilization afforded by the vertebroplasty alone. Long-term studies are warranted to assess the efficacy and durability of this unique approach.  相似文献   
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α Oscillations in sensory cortex, under frontal control, desynchronize during attentive preparation. Here, in a selective attention study with simultaneous EEG in humans of either sex, we first demonstrate that diminished anticipatory α synchrony between the mid-frontal region of the dorsal attention network and ventral visual sensory cortex [frontal-sensory synchrony (FSS)] significantly correlates with greater task performance. Then, in a double-blind, randomized controlled study in healthy adults, we implement closed-loop neurofeedback (NF) of the anticipatory α FSS signal over 10 d of training. We refer to this closed-loop experimental approach of rapid NF integrated within a cognitive task as cognitive NF (cNF). We show that cNF results in significant trial-by-trial modulation of the anticipatory α FSS measure during training, concomitant plasticity of stimulus-evoked α/θ responses, as well as transfer of benefits to response time (RT) improvements on a standard test of sustained attention. In a third study, we implement cNF training in children with attention deficit hyperactivity disorder (ADHD), replicating trial-by-trial modulation of the anticipatory α FSS signal as well as significant improvement of sustained attention RTs. These first findings demonstrate the basic mechanisms and translational utility of rapid cognitive-task-integrated NF.SIGNIFICANCE STATEMENT When humans prepare to attend to incoming sensory information, neural oscillations in the α band (8–14 Hz) undergo desynchronization under the control of prefrontal cortex. Here, in an attention study with electroencephalography, we first show that frontal-sensory synchrony (FSS) of α oscillations during attentive preparation significantly correlates with task performance. Then, in a randomized controlled study in healthy adults, we show that neurofeedback (NF) training of this α FSS signal within the attention task is feasible. We show that this rapid cognitive NF (cNF) approach engenders plasticity of stimulus-evoked neural responses, and improves performance on a standard test of sustained attention. In a final study, we implement cNF in children with attention deficit hyperactivity disorder (ADHD), replicating the improvement of sustained attention found in adults.  相似文献   
58.
Anemia is a common health problem but control of anemia in pregnant women is less well studied. The purpose was to study prevalence of anemia in young pregnant women, correlate with indices and study significance of identification of hemoglobinopathies. Of the 120 pregnant women, Hb was less than 8 g% in 58 (44.2%). Seventy-eight (65%) had iron deficiency, 22 (18.3%) had dimorphic anemia, and 14 (11.6%) had hemolytic anemia. Megaloblastic anemia was present in 6 (5%). Of hemolytic anemia, 50% were thalassemia trait. MCV< 76 fl was observed in 88 (73.3 %) cases. MCV<76 fl and MCH < 27 pg had 100 % sensitivity and 28.7 % specificity for screening of beta-thalassemia trait. NESTROFT had comparable sensitivity but lower specificity (14.9%). Sixty-three percent (60/78) of IDA had increased RDW whereas 78 % (11/14) of hemolytic anemia had RDW value in normal range (p value< 0.05). MCV/RBC of <14 was more specific parameter (96.8%) for beta-thalassemia trait. Four high-risk couples were identified. Thus, moderate to severe anemia was observed in most pregnant women. Hemoglobinopathies should be screened in antenatal clinics to identify the couples that would need a prenatal test. A lower MCV/RBC with RDWin the normal range may be useful in screening for thalassemia trait in pregnant women.  相似文献   
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