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91.
高效液相色谱法测定消痰咳片的含量 总被引:2,自引:0,他引:2
目的:采用反相色谱法同时测定消痰咳片中两种主要成分甲氧苄啶和磺胺体的含量。方法:以乙腈:0.1%H3PO4(15:85)为流动相,检测波长254nm,HPLC法测定含量。结果:试验表明,甲氧苄啶和磺胺林在0.8-8ug范围内呈良好的线性关系,回归方程分别为Y=-1127.1+110.2x(r=0.9994),Y=-1852.3 256.2x(r=0.9996),相对标准偏差分别为2.1%和0.8%。结论:该方法简便、准确、可靠。 相似文献
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D. van Zoeren-Grobben JHN Lindeman E. Houdkamp RMW Moison JT Wijnen HM Berger 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(12):1356-1362
Markers of oxidative stress and antioxidant activity in plasma and erythrocytes were studied for 14 d after birth in infants with neonatal respiratory distress syndrome ( n = 9) and controls ( n = 36). In plasma, the total radical trapping antioxidant capacity and the chain-breaking antioxidants vitamin C, sulfhydryl groups and bilirubin were similar. The differences in uric acid levels were not consistent, but vitamin E levels and vitamin E/total-lipid ratio were lower in the neonatal respiratory distress group ( p < 0.01). In erythrocytes, the antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase did not differ postnatally. Indicators of oxidative damage in plasma (sulfhydryl/protein ratio and thiobarbituric acid reactive substances) showed the same postnatal course in both groups and were not influenced by oxygen therapy. In erythrocytes the reduced/oxidized glutathione ratio showed no consistent differences. In conclusion, this study, using erythrocytes and plasma, does not provide convincing evidence of oxidative damage and diminished antioxidant defenses in preterm infants with neonatal respiratory distress syndrome. 相似文献
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Phosphoinositide 3-kinase is involved in the induction of the human sperm acrosome reaction downstream of tyrosine phosphorylation 总被引:7,自引:4,他引:3
Fisher HM; Brewis IA; Barratt CL; Cooke ID; Moore HD 《Molecular human reproduction》1998,4(9):849-855
In somatic cells phosphoinositide 3-kinase (PI 3-kinase) is activated upon
interaction with both receptor tyrosine kinases (RTK) and G- proteins
resulting in the production of moieties involved in the inositol
phospholipid signalling pathway. As G proteins, RTK and the inositol
phospholipids have all been implicated in the human sperm acrosome
reaction, experiments were carried out to determine whether PI 3-kinase was
also involved in this phenomenon. Wortmannin is a selective inhibitor of PI
3-kinase and was shown to significantly inhibit the acrosome reaction
induced by both mannose-bovine serum albumin (mannose-BSA) (10, 50 and 100
nM) and a polyclonal antibody raised against an extracellular region of the
sperm zona receptor kinase (ZRK, at 100 nM only). Wortmannin did not
inhibit the A23187- or progesterone-induced acrosome reaction. These
results suggest that PI 3- kinase is involved in the human sperm acrosome
reaction. The levels of tyrosine phosphorylation of sperm proteins as
detected by Western blotting using antiphosphotyrosine antibodies was not
affected by wortmannin in agonist (A23187 and mannose-BSA)-stimulated
spermatozoa. This indicated that PI 3-kinase operates downstream of
tyrosine phosphorylation in the signal transduction cascade which leads to
the human sperm acrosome reaction.
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Influence of age and comorbidity on treatment choice and survival in elderly patients with breast cancer 总被引:3,自引:0,他引:3
Liesbeth Bergman Gert Dekker Elly HM van Kerkhoff Hans L. Peterse Johannes A. van Dongen Flora E. van Leeuwen 《Breast cancer research and treatment》1991,18(3):189-198
Summary To determine the effect of age and comorbid diseases on treatment choice and survival, the medical records of 300 breast cancer patients of 55 years and older were reviewed. All patients were admitted to the Netherlands Cancer Institute (NKI) for first treatment between 1980 and 1987. Patients were classified according to severity level of comorbid diseases. Physicians were found to treat women of 75 years and older less often with adjuvant radiotherapy after a mastectomy, and more often to employ only primary endocrine treatment for local stage disease, as compared with younger patients. According to the treatment guidelines of the institute, the study sample was divided into patients who received standard vs. non-standard treatment. The treatment of 38 women (13.1%) did not correspond with the guidelines. Of these, 84% were 75 years and older and 50% had a severe comorbidity status. Logistic regression analysis indicated that advanced age, per se, was a better indicator of the risk of not being treated according to protocol than the comorbidity status. Cox multivariate analyses demonstrated that neither the severity of the comorbidity status nor the differences in treatment between younger and older patients had a significant effect on the risk of dying from breast cancer or on the risk of developing recurrences. In this analysis, age 75 years or more proved to be a significant and independent predictor of a worse overall and disease-specific survival as compared to age between 65–74 years. 相似文献
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