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Highly expanded nanocomposite foams of polypropylene and carbon nanotubes (PP/CNT) are formed using supercritical carbon dioxide (scCO2) technology. The foaming parameters (temperature, pressure) are investigated to establish their influence on the morphology of the resulting foams and their impact on the electrical conductivity. As promising electromagnetic‐interference (EMI) absorbers, the EMI shielding performance of the foams is determined, and a preliminary relationship is established between foam morphology and the EMI shielding performance. The best candidates are highly expanded foams with a volume expansion of >25, containing 0.1 vol% CNTs; they are able to absorb more than 90% of the incident radiation between 25 and 40 GHz.

  相似文献   

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Journal of Digital Imaging - We present a hybrid algorithm to estimate lung nodule malignancy that combines imaging biomarkers from Radiologist’s annotation with image classification of CT...  相似文献   
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Ribavirin and remdesivir have been preclinically reported as potential drugs for the treatment of SARS-CoV-2 infection, while light silver tetrylene complexes (NHEPh–AgCl and (NHEPh–AgCl)2 with E = C, Si, and Ge) have gained significant interest due to their promising applicability on the cytological scale. Firstly, the structures and bonding states of silver–tetrylene complexes (NHE–Ag) and bis-silver–tetrylene complexes (NHE–Ag-bis) were investigated using density functional theory (DFT) at the BP86 level with the def2-SVP and def2-TZVPP basis sets. Secondly, the inhibitory capabilities of the carbene complexes (NHC–Ag and NHC–Ag-bis) and the two potential drugs (ribavirin and remdesivir) on human-protein ACE2 and SARS-CoV-2 protease PDB6LU7 were evaluated using molecular docking simulation. The carbene ligand NHC bonds in a head-on configuration with AgCl and (AgCl)2, whereas, the other NHE (E = Si and Ge) tetrylene ligands bond in a side-on mode to the metal fragments. The bond dissociation energy (BDE) of the NHE–Ag bond in the complex families follows the order of NHC–Ag > NHSi–Ag > NHGe–Ag and NHSi–Ag-bis > NHGe–Ag-bis > NHC–Ag-bis. The natural bond orbital analysis implies that the [NHEPh→AgCl] and [(NHEPh)2→(AgCl)2] donations are derived mainly from the σ- and π-contributions of the ligands. The docking results indicate that both the ACE2 and PDB6LU7 proteins are strongly inhibited by silver–carbene NHC–Ag, bis-silver–carbene NHC–Ag-bis, ribavirin, and remdesivir with the docking score energy values varying from −17.5 to −16.5 kcal mol−1 and −16.9 to −16.6 kcal mol−1, respectively. The root-mean-square deviation values were recorded to be less than 2 Å in all the calculated systems. Thus, the present study suggests that silver–carbene NHC–Ag and bis-silver–carbene NHC–Ag-bis complexes are potential candidates to inhibit ACE2 and PDB6LU7, and thus potentially conducive to prevent infection caused by the SARS-CoV-2 virus.

Simultaneous inhibition of silver–carbene complexes to ACE2 and PDB6LU7 is conducive for the prevention of SARS-CoV-2 infection: a virtual prediction.  相似文献   
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BACKGROUND: Tuberculous meningitis (TBM) caused by Mycobacterium tuberculosis resistant to 1 or more antituberculosis drugs is an increasingly common clinical problem, although the impact on outcome is uncertain. METHODS: We performed a prospective study of 180 Vietnamese adults admitted consecutively for TBM. M. tuberculosis was cultured from the cerebrospinal fluid (CSF) of all patients and was tested for susceptibility to first-line antituberculosis drugs. Presenting clinical features, time to CSF bacterial clearance, clinical response to treatment, and 9-month morbidity and mortality were compared between adults infected with susceptible and those infected with drug-resistant organisms. RESULTS: Of 180 isolates, 72 (40.0%) were resistant to at least 1 antituberculosis drug, and 10 (5.6%) were resistant to at least isoniazid and rifampicin. Isoniazid and/or streptomycin resistance was associated with slower CSF bacterial clearance but not with any differences in clinical response or outcome. Combined isoniazid and rifampicin resistance was strongly predictive of death (relative risk of death, 11.63 [95% confidence interval, 5.21-26.32]) and was independently associated with human immunodeficiency virus infection. CONCLUSIONS: Isoniazid and/or streptomycin resistance probably has no detrimental effect on the outcome of TBM when patients are treated with first-line antituberculosis drugs, but combined isoniazid and rifampicin resistance is strongly predictive of death.  相似文献   
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The authors report the case of a 53 year old patient who had undergone triple coronary bypass surgery for unstable angina. Recurrence of chest pain 4 months after surgery led to control coronary angiography which showed severe stenosis of the proximal and distal parts of the aorto-right coronary graft. Endoluminal dilatation was performed a few days later but, during angiography, complete occlusion of the graft was observed. This was repermeabilised without difficulty and a "remodelling" of the graft was carried out. The outcome was favourable with the complete regression of symptoms. The following alternatives to surgery are discussed: in cases of thrombosis which usually occur in the month following surgery, fibrinolysis may be attempted with a high success rate but a significant risk of haemo-pericardium: in cases of fibrous proliferation of the intima leading to stenosis or occlusion, endoluminal dilatation seems to be the procedure of choice, but this must always be carried out under surgical cover.  相似文献   
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Nguyen P  Moisini I  Geiger TL 《Blood》2003,102(13):4320-4325
Recent preclinical and clinical trials have demonstrated the therapeutic potential of T lymphocytes redirected with genetically engineered T-cell receptor (TCR) surrogates against infected, cancerous, or autoreactive cells. These surrogate TCRs link a ligand-recognition domain to signaling regions from the TCR. We previously compared the function of surrogate TCRs that include TCR or TCR and CD28 signaling regions. We found that primary murine T cells modified to specifically target Kb-restricted CD8+ T cells using either Kb-zeta or Kb-CD28-zeta receptors had similar functional activities, although the CD28-zeta receptor showed a 2-fold to 4-fold decreased expression. We have now identified a previously unrecognized dileucine motif in the murine CD28 signaling domain that accounts for this reduced expression. Inactivation of this motif increased chimeric receptor surface expression 2- to 5-fold. T cells expressing the dileucine-mutated CD28-zeta chimeric receptor demonstrated enhanced proliferation, cytokine production, and cytolytic activities. Further, cells expressing this dileucine-mutated receptor were highly effective in eliminating antigen-specific CD8+ T lymphocytes in vivo. These results therefore identify a critical motif limiting the function of receptor-modified T lymphocytes, demonstrate that inactivation of this motif enhances chimeric receptor function, and illustrate a potential novel application of receptor-modified T lymphocytes in the induction of immune tolerance.  相似文献   
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