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31.
The purpose of the present study was to investigate the effect of the low power laser therapy on the acute inflammatory process. Male Wistar rats were used. The rat paw oedema was induced by sub-plantar injection of carrageenan, the paw volume was measured before and 1, 2, 3 and 4 h after the injection using a hydroplethysmometer. To investigate the mechanism action of the Ga-Al-As laser on inflammatory oedema, parallel studies were performed using adrenallectomized rats or rats treated with sodium diclofenac. Different laser irradiation protocols were employed for specific energy densities (EDs), exposure times and repetition rates. The rats were irradiated with the Ga-Al-As laser during 80 s each hour. The ED that produced an anti-inflammatory effect were 1 and 2.5 J/cm(2), reducing the oedema by 27% (P<0.05) and 45.4% (P<0.01), respectively. The ED of 2.5 J/cm(2) produced anti-inflammatory effects similar to those produced by the cyclooxigenase inhibitor sodium diclofenac at a dose of 1 mg/kg. In adrenalectomized animals, the laser irradiation failed to inhibit the oedema. Our results suggest that low power laser irradiation possibly exerts its anti-inflammatory effects by stimulating the release of adrenal corticosteroid hormones.  相似文献   
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Sunto. Applicando nozioni già utilizzate in precedenti lavori dello stesso A. sul problema della quadratura delle superficie, si danno formule generali di trasformazione degli integrali doppi.  相似文献   
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Abstract

The phytochemical examination of the polar constituents of Sambucus ebulus L. leaves led to the identification of patrinoside (1) and of a new diglycoside iridoid, patrinoside-aglycone-11-O-[β-D-glucopyranosyl-(1→6)-2′-deoxy-β-D-glucopyranoside] (trivially named as sambuloside) (2). Both of these structures have been assigned by spectroscopic means (NMR and MS).  相似文献   
36.
Viologens are generally synthesized by N-alkylating 4,4′-bipyridine with alkyl halides. Under conventional heating conditions, however, their synthesis suffers from long reaction times and, often, low yields. In this work, symmetric and asymmetric viologens were synthesized under the assistance of microwave irradiation in good to excellent yields and in short reaction times.  相似文献   
37.
Molecular dynamics simulations and infrared spectroscopy were used to determine the hydrogen bond patterns of glycerol and its mixtures with water. The ability of glycerol/water mixtures to inhibit ice crystallization is linked to the concentration of glycerol and the hydrogen bonding patterns formed by these solutions. At low glycerol concentrations, sufficient amounts of bulk-like water exist, and at low temperature, these solutions demonstrate crystallization. As the glycerol concentration is increased, the bulk-like water pool is eventually depleted. Water in the first hydration shell becomes concentrated around the polar groups of glycerol, and the alkyl groups of glycerol self-associate. Glycerol-glycerol hydrogen bonds become the dominant interaction in the first hydration shell, and the percolation nature of the water network is disturbed. At glycerol concentrations beyond this point, glycerol/water mixtures remain glassy at low temperatures and the glycerol-water hydrogen bond favors a more linear arrangement. High glycerol concentration mixtures mimic the strong hydrogen bonding pattern seen in ice, yet crystallization does not occur. Hydrogen bond patterns are discussed in terms of hydrogen bond angle distributions and average hydrogen bond number. Shift in infrared frequency of related stretch and bend modes is also reviewed.  相似文献   
38.
Two dialkylated isocyanides were first synthesised from simple starting materials and then used as building blocks for the synthesis of indolizidines via a novel radical cyclisation/N-alkylation/ring closing metathesis strategy. Several functionalised indolizidines were accessed in good to excellent yields.  相似文献   
39.
A novel protein with factor Xa-like activity was isolated from Lonomia obliqua caterpillar spicules by gel filtration chromatography and reversed-phase high-performance liquid chromatography. The protein had a mass of 20745.7 Da, as determined by mass spectrometry, and contained four Cys residues. Enzymatic hydrolysis followed by de novo sequencing by tandem mass spectrometry was used to determine the primary structure of the protein and the cysteine residues linked by disulfide bridges. The positions of 24 sequenced tryptic peptides, including the N-terminal, were deduced by comparison with a homologous protein from the superfamily Bombycoidea. Approximately 90% of the primary structure of the active protein was determined.  相似文献   
40.
The effects of the entrance channel and shell structure on the experimental evaporation residues have been studied by analyzing the 32S + 182W, 48Ti + 166Er and 60Ni + 154Sm reactions leading to 214Th*; the 40Ar + 181Ta reaction leading to 221Pa*; the 48Ca + 243Am, 248Cm, 249Cf reactions leading to the 291115, 296116 and 297118 superheavy compound nuclei, respectively. The fusion mechanism and the formation of evaporation residues of heavy and superheavy nuclei have been studied. In calculations of the excitation functions for capture, fusion and evaporation residues we used such characteristics as mass asymmetry of nuclei in the entrance channel, binding energies and shape of colliding nuclei, potential energy surface, driving potential, partial-fusion cross-sections and survival probability of the compound nucleus, ratio at each step along the de-excitation cascade of the compound nucleus. The calculations have allowed us to make useful conclusions about the mechanism of the fusion-fission process, which is in competition with the quasifission process, and the production of the evaporation residues.Received: 22 April 2003, Revised: 26 June 2003, Published online: 18 December 2003PACS: 25.70.Gh Compound nucleus - 25.70.-z Low and intermediate energy heavy-ion reactions - 27.80. + w - 27.90. + b   相似文献   
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