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M Chatterjee K Basu D Basu D Bannerjee N Pramanik SK Guha RP Goswami SK Saha C Mandal 《Canadian Metallurgical Quarterly》1998,114(3):408-413
BACKGROUND: Interleukin 10 (IL-10) decreases the severity of experimental acute pancreatitis. The role of endogenous IL-10 in modulating the course of pancreatitis is currently unknown. AIMS: To examine the systemic release of IL-10 and its messenger RNA production in the pancrease, liver, and lungs and analyse the effects of IL-10 neutralisation in caerulein induced acute pancreatitis in mice. METHODS: Acute necrotising pancreatitis was induced by intraperitoneal caerulein. Serum levels of IL-10 and tumour necrosis factor (TNF), and tissue IL-10 and TNF-alpha gene expression were assessed. After injecting control antibody or after blocking the activity of endogenous IL-10 by a specific monoclonal antibody, the severity of acute pancreatitis was assessed in terms of serum enzyme release, histological changes, and systemic and tissue TNF production. RESULTS: In control conditions, serum IL-10 levels increased and correlated with the course of pancreatitis, with a maximal value eight hours after induction. Both IL-10 and TNF-alpha messengers showed a similar course, and were identified in the pancreas, liver, and lungs. Neutralisation of endogenous IL-10 significantly increased the severity of pancreatitis and associated lung injury as well as serum TNF protein levels (+75%) and pancreatic, pulmonary, and hepatic TNF messenger expression (+33%, +29%, +43%, respectively). CONCLUSIONS: In this non-lethal model, systemic release of IL-10 correlates with the course of acute pancreatitis. This anti-inflammatory response parallels the release of TNF and both cytokines are produced multisystemically. Endogenous IL-10 controls TNF-alpha production and plays a protective role in the local and systemic consequences of the disease. 相似文献
23.
Spin Filtering through Single‐Wall Carbon Nanotubes Functionalized with Single‐Stranded DNA
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High spin polarization materials or spin filters are key components in spintronics, a niche subfield of electronics where carrier spins play a functional role. Carrier transmission through these materials is “spin selective,” that is, these materials are able to discriminate between “up” and “down” spins. Common spin filters include transition metal ferromagnets and their alloys, with typical spin selectivity (or, polarization) of ≈50% or less. Here carrier transport is considered in an archetypical one‐dimensional molecular hybrid in which a single wall carbon nanotube (SWCNT) is wrapped around by single stranded deoxyribonucleic acid (ssDNA). By magnetoresistance measurements it is shown that this system can act as a spin filter with maximum spin polarization approaching ≈74% at low temperatures, significantly larger than transition metals under comparable conditions. Inversion asymmetric helicoidal potential of the charged ssDNA backbone induces a Rashba spin‐orbit interaction in the SWCNT channel and polarizes carrier spins. The results are consistent with recent theoretical work that predicted spin dependent conductance in ssDNA‐SWCNT hybrid. Ability to generate highly spin polarized carriers using molecular functionalization can lead to magnet‐less and contact‐less spintronic devices in the future. This can eliminate the conductivity mismatch problem and open new directions for research in organic spintronics. 相似文献
24.
Low temperature preparation of nanocrystalline solid solution of strontium barium niobate by chemical process 总被引:1,自引:0,他引:1
SrxBa1-xNb2O6 (with x = 0.4, 0.5 and 0.6) powders have been prepared by thermolysis of aqueous precursor solutions consisting of triethanolamine
(TEA), niobium tartarate and, EDTA complexes of strontium and barium ions. Complete evaporation of the precursor solution
by heating at ∼ 200°C, yields in a fluffy, mesoporous carbon rich precursor material, which on calcination at 750°C/2 h has
resulted in the pure SBN powders. The crystallite and average particle sizes are found to be around 15 nm and 20 nm, respectively. 相似文献
25.
Bladder injury in the neonatal period is an exceedingly rare phenomenon that is usually iatrogenic. Bladder rupture as a complication of umbilical catheterization in a newborn with urinary ascites, respiratory distress and hematuria is presented and discussed. 相似文献
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S C Patil G Swaminathan Manoj Kumar P V Sastry S B Ogale S M Kanetkar A Pramanik 《Bulletin of Materials Science》1991,14(5):1249-1255
Non-contact processing technique involving the use of CW and pulsed CO2 laser irradiation has been used for reducing the core loss of cold-rolled grain-oriented silicon steel. Laser scribing perpendicular
to the rolling direction resulted in a refinement of domain wall spacing which subsequently reduced the loss of silicon steel.
It was found that laser irradiation was more effective in a specimen with higher magnetic induction (Hi-B) and the loss was
reduced by more than 10% under optimum conditions of the laser irradiation and the scribing speed. Since laser processing
is a non-contact technique, it can be easily applied to the production line of the silicon steel. 相似文献
27.
Various compositions of nano-sized (NiMoO4)x-doped Bi2Ti4O11 (x = 0.01, 0.05, 0.1) composites have been prepared by chemical solution decomposition (CSD) method using triethanolamine (TEA) as complexing agent. Ni(II) is one of reactive species on the catalyst surface and Mo(VI) ion helps to compensate the charge of the lattice. The photocatalysts based on the above compositions have been tested for photobleaching of methyl orange (MO) solution under Hg-lamp. The prepared nanopowders are characterized by XRD, EDAX, UV–vis spectra, specific surface area (BET), zeta potential, ESR and HRTEM analyses. The average particle size of nickel molybdate-doped bismuth titanate lies around 30 ± 2 nm measured from TEM. Result shows nickel molybdate-doped bismuth titanate (NiMoO4)x(Bi2Ti4O11)1−x (NMxBT1−x; x = 0.01) composite is found to be more photoactive compared all the compositions studied except degussa P25 titania. 相似文献
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The two-dimensional linear gravity waves created by a moving oscillatory source in an incompressible, inviscid, electrically conducting fluid of infinite depth where a constant magnetic field acts outside the air-water interface are considered. To determine the unsteady asymptotic waves, Bleistien's method had been applied to the Fourier transform solution. Several physically interesting results about the four waves generated, together with their fronts, are found and also the effect of magnetic force on the gravity waves has been studied. 相似文献
30.