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991.
992.
The two stage gravimetric technique used for the measurements of industrial aerosols, in combination with measurements of mass-related concentrations of particles in the air, provided major hygienic information on the sizes (dispersity) of the inhaled particles. The results of the measurements taken in various branches of industry, ore and alluval deposit mines clarified the fundamental properties of the particles' distribution into rough and thin fractions. An express two-stage gravimetric technique for determining ore aerosol dispersal contents was proposed, along with the technical characteristics of the USSR-produced dust counters. 相似文献
993.
994.
R Menningen M Günther N B?nninghoff C D Stahlknecht I Kubitza J Kusche 《Agents and actions》1986,18(1-2):38-40
In the operative treatment of appendicitis the so called negative appendectomy is an important issue because of its increased morbidity. From the hypothesis that the intestinal diamine oxidase activity is a suitable marker of mucosal integrity, the distribution pattern of the enzyme in appendices histologically classified as inflamed or not inflamed was studied. Histologically apparent inflammation of the appendix was connected with a significant reduction of diamine oxidase activity. The determination of this enzymic activity may be a simple and sensitive test for mucosal inflammation of the appendix even at a very early state. This could reduce the rate of negative appendectomies and influence thereby risk-cost-benefit calculations. 相似文献
995.
Gestational age determination based on obstetric dating criteria, early pregnancy ultrasound scans, Dubowitz examinations, and ultrasound scans performed shortly before delivery were reviewed for 69 preterm infants requiring neonatal intensive care. The last ultrasound scans underestimated gestational age by a median of 8 days, and by 2 weeks or more in 20 of the 69 cases, as opposed to best dating criteria. Ultrasonic fetal weight estimation was more accurate, but erred by more than 20% in 10% of cases. When obstetric decisions regarding preterm neonates must be made without prior information regarding gestational age, late ultrasound findings must be applied with extreme care. 相似文献
996.
A quantitative spectrophotometric method has been developed for determining the impurity of isonaphthazarin in samples of
tetraxolin. The relative error of determination is about 1.0% at a confidence probability of P = 0.95%. The procedure is recommended for the quantitative control of the possible impurity of isonaphthazarin in the parent
substance of tetraxolin.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 1, pp. 38–40, January, 2007. 相似文献
997.
D. V. Moiseev S. I. Marchenko A. M. Moiseeva T. V. Trukhacheva P. T. Petrov A. I. Zhebentyaev 《Pharmaceutical Chemistry Journal》2007,41(1):25-33
Pyrimidine derivatives are widely used for the treatment of viral diseases and cancer. The analysis of pyrimidine derivatives
is typically performed using various chromatographic techniques, in particular, reversed-phase high performance liquid chromatography
(HPLC). The separation is typically carried out with (7–30)-cm-long C8 and C18 silica gel columns, mainly at room temperature, and a 1–1.5 ml-min eluent flow rate. The column is eluted in an isocratic
or gradient system, and a variety of mobile phases have been proposed. The detection is based on optical absorption or fluorescence
measurements, or makes use of mass spectrometry. Various methods of extraction of pyrimidine derivatives from biological samples
are discussed, and the corresponding detection limits are presented.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 5, pp. 26–34, May, 2007. 相似文献
998.
Y. O. Karatasso I. V. Logunova M. G. Sergeeva E. N. Nikolaev S. D. Varfolomeev V. V. Chistyakov 《Pharmaceutical Chemistry Journal》2007,41(3):166-169
A highly sensitive method for the quantitative determination of a potential antiarrhythmic drug (OF-7976) in the blood plasma
has been developed. The method is based on the electron spray ionization/mass spectrometry (ESI-MS) technique without preliminary
chromatographic separation and makes use of nibentan as the internal standard. A linear relationship between drug concentration
and the peak intensity of ions of the analyzed substance (m/z = 398) and the internal standard (m/z = 382) is established. The detection limit is 3 ng/(0.5 ml plasma). The method is linear from 3 to 25 ng/(0.5 ml plasma)
with a correlation coefficient of 0.98. The coefficient of variation was less than 7 %.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 3, pp. 45–48, March, 2007. 相似文献
999.
1000.
Alan Willmore Tim Sladden Lucy Bates Craig B Dalton 《International journal of health geographics》2006,5(1):30-14