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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   
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A 59-year-old hypertensive male, 1 year after uncomplicatedmitral annuloplasty for regurgitation with MAZE procedure, witha history of chronic obstructive pulmonary disease and repeatedpulmonary  相似文献   
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The relationship of skin reactivity and serum immunoglobulin E (IgE) levels to the prevalence of chronic respiratory symptoms and to ventilatory capacity is examined in workers exposed to different organic aerosols. The results from group of control workers similarly tested are also presented. Workers exposed to occupational allergens had positive skin tests more frequently than did controls, except for soy bean workers. Workers with positive skin tests to occupational allergens had a higher prevalence of almost all symptoms than those with negative skin tests although the differences did not always reach statistical significance. Workers with positive skin reactions in general had significantly higher serum IgE levels than did workers with negative skin reactions. There were across-shift reductions of ventilatory capacity in all groups of exposed workers, varying for forced vital capacity from 1.7% to 13.3%, for forced expiratory volume from 0.4%–21.9%, for maximum flow rates at 50% from 1.5% to 16.1% and for maximum flow rates at the last 25% of control vital capacity from 0% to 24.9%. There was, however, no correlation between acute and chronic lung function changes and skin reactivity or IgE values. Our data suggest that although exposure to organic aerosols may be associated with frequent immunologic reactions, these findings do not predict objective respiratory impairment.The research was supported in part by grant no. JBP 733 from the National Institutes of Health, Bethesda, Md., USA, and by grant no. RO1 OHO-2593-04 from the National Institutes of Occupational Safety and Health, Centers for Disease Control, Atlanta, Ga., USA  相似文献   
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Patients with testicular tumors receiving the Einhorn combination chemotherapy with cisplatinum administration for five consecutive days were evaluated for signs of glomerular filtration rate impairment by means of serum beta 2-microglobulin measurements before and on days 2 and 5 after cessation of cisplatin administration and then before repeated cycles of the same chemotherapeutic regimen. Though no significant changes in the level of serum beta 2-microglobulin could be found, an evident increase in the values was seen indicating that in more aggressive cisplatin administration schedules not only tubular impairment might contribute to possible nephrotoxic effects.  相似文献   
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Anatomical examinations (33 cadavers) for studying parasympathetic innervation of the upper abdominal organs formed the basis for developing a new variant of proximal gastric vagotomy--anterior seromyotomy of the body and fundus of the stomach in combination with posterior truncal or posterior selective vagotomy. This variant excludes mobilization of the esophagus and makes it possible to preserve the ligament apparatus of the esophago-gastric junction as well as the parasympathetic innervation of the pancreas, small and large intestine, kidneys, and adrenals, which may be a measure for the prevention of some ++post-vagotomy complications.  相似文献   
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