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131.
Oral diseases pose a major threat to public health across the globe. Diseases such as dental caries, periodontitis, gingivitis, halitosis, and oral cancer affect people of all age groups. Moreover, unhealthy diet practices and the presence of comorbidities aggravate the problem even further. Traditional practices such as the use of miswak for oral hygiene and cloves for toothache have been used for a long time. The present review exhaustively explains the potential of natural products obtained from different sources for the prevention and treatment of dental diseases. Additionally, natural medicine has shown activity in preventing bacterial biofilm resistance and can be one of the major forerunners in the treatment of oral infections. However, in spite of the enormous potential, it is a less explored area due to many setbacks, such as unfavorable physicochemical and pharmacokinetic properties. Nanotechnology has led to many advances in the dental industry, with various applications ranging from maintenance to restoration. However, can nanotechnology help in enhancing the safety and efficacy of natural products? The present review discusses these issues in detail.  相似文献   
132.
An improved method of saxitoxin analysis in urine using continuous-flow fast-atom bombardment mass spectrometry was developed. Parameters studied were matrix composition, matrix flow, temperature of probe tip, probe-tip design and sample extraction. Optimal detection was obtained using the following matrix composition: 5% glycerol, 0.5% acetic acid, 0.025% sodium dodecylsulfate, 0.1% polyethylene glycol (PEG) 400 and 0.5% PEG 300; probe-tip temperature: (approximately 55 degrees C); flow rate: 5 or 8 microL per min.; probe tip: Olson-Hogge design. The STX standard was detected at 200 pg with signal-to-noise ratio of 11. The percent recovery of saxitoxin from human urine after clean-up on a weak cation exchange column was 75%.  相似文献   
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Precise energies and intensities of about 450γ-rays of the197Au(n, γ)198Au reaction have been investigated in the energy range from 30 keV to 1 MeV with a bentcrystal spectrometer. Prompt and delayedγ-γ coincidences have been studied with Ge(Li) detectors. A half-life of 124±4 ns has been measured for the state at 312.036 keV, which is found to decay to the ground state through the cascade 97.195–214.841 keV. A new level scheme based on these results has been constructed which contains 160 transitions. Spin and parity assignments have been made for most of the levels.  相似文献   
135.
Electrical resistivity, magnetic susceptibility, and heat capacity of V5O9 have been measured through its phase transition temperature (Tt) around 129 K. The associated changes in enthalpy and entropy were found to be 2095 J/mole and 19.24 J/mole · deg., respectively. A qualitative thermodynamic analysis has been attempted to correlate the crystal symmetry, electrical, magnetic, and heat capacity behavior at Tt. The metal-semiconductor transition appears as a consequence of the crystallographic order-disorder process, since the electrical and magnetic contributions to configurational entropy change are relatively small.  相似文献   
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Summary In general the addition of non-electrolyte to hydrophobic sols results into an irregular change in the stability of the latter, towards electrolyte coagulation. Precipitation concentration of potassium chloride for copper ferrocyanide sol changes in the presence of ethyl alcohol, glycol or glycerol. Ethyl alcohol sensitizes while others stabilise the sol to different extents. In presence of these alcohols, electrolytic coagulation of copper ferrocyanide sol is attended by a decrease in the conductance and hydrogen ion concentration as compared to a pure sol (sol without non-electrolyte).
Zusammenfassung Im allgemeinen verursacht das Zufügen von Nicht-Elektrolyten zu hydrophoben Solen eine irregul?re ?nderung der Stabilit?t der letzteren hinsichtlich der Elektrolytkoagulation. Die F?llungskonzentration von Kaliumchlorid für Kupfer-Ferrocyanid-Sol ?ndert sich bei Gegenwart von ?thylalkohol, Glykol oder Glycerin. ?thylalkohol sensibilisiert, w?hrend die anderen das Sol in verschiedenem Ausma\ stabilisieren. In Gegenwart dieser Alkohole ist die Elektrolytkoagulation des Kupfer-Ferrocyanid-Sols von einer Abnahme der Leitf?higkeit und der Wasserstoffionenkonzentration, verglichen mit den reinen Solen ohne Nicht-Elektrolyt begleitet.
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139.
The extraction of strontium(II) and yttrium(III) ions from aqueous solutions at various pH values into methyl isobutyl ketone containing I-phenyl-3-methyl-4-caprylpyrazolone-5 is described. Quantitative extraction of Sr and Y at pH 8.6–10 and pH 2.8–5.4 respectively is utilized for the carrier-free production of 90Y from 90Sr–90Y mixtures and 89Sr from neutron-irradiated yttrium oxide. A clean separation of these elements from each other and more than 95% calculated activities were recovered  相似文献   
140.
Pulse radiolysis of MIT and DIT irradiated to doses from 2.8·104 to 85·104 rads is studied by ascending chromatography. The 3-iodo-4,5-dihydroxyphenylalanine (DOPA-I) and 3-iodo-4-hydroxyphenylalanine have been identified as first stages of degradations of MIT and DIT, respectively. G values are 0.015 for MIT (10−5M) and 0.004 for DIT (0.5·10−5M). By self decomposition MIT is degraded less rapidly than DIT and there is no formation of DOPA-I.   相似文献   
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