华　中　科　技　大　学　博　士　学　位　论　文

Results: The concentrations of VEGF and endostatin were significantly higher in malignant than those in nonmalignant effusions(P both <0.01). For VEGF, sensitivity, specificity and accuracy to diagnose the malignant pleural effusion were57.5%, 81.0%, and 69.5%, respectively. Similarly, for endostatin, the sensitivity, specificity and accuracy to diagnose the malignant pleural effusion were50.0%, 90.5%, and 70.7%, respectively. Unexpectedly, when VEGF/endostatin ratio was analysed, sensitivity, specificity and accuracy were significantly rising up to 97.5%, 90.5%, 93.9%. Conclusion: These findings suggest that elevated levels of VEGF and endostatin in pleural effusions are helpful to make the diagnosing of malignant pleural effusions and differentiate malignant from tuberculosis pleural effusions, especially VEGF/endostatin ratio can increase sensitivity, specificity and accuracy.

【Key words】Pleural effusion; Vascular endothelial growth factor; Endostatin

Part III

Changes of levels of sera vascular endothelial growth factor and endostatin in smokers

【Abstract】Objective: To explore the changes and clinical significance of levels of serum VEGF and endostatin in smokers. Methods: In a case-control study, levels of serum VEGF and endostatin were determined in 82 smokers with lung cancer, 82 pair-matched smokers without lung cancer and 20 healthy non-smokers by enzyme linked immunoabsent assay (ELISA) or competitive enzyme immunoassay. Results: The levelss of serum VEGF in smokers with lung cancer (16.1±7.9ng/L) were markedly higher than those in the other two groups (both P <0.01). And the levels of serum VEGF in smokers without lung cancer were significantly higher than those in healthy nonsmokers (P <0.05). The levels of serum endostatin in smokers with lung cancer were significantly higher than those in healthy nonsmokers (P <0.01), but were not significantly different from those in smokers without lung cancer (P >0.05). Notably, the ratio of endostatin to VEGF in smokers with lung cancer (1.3±0.5) was significantly lower than that in other two groups (both P <0.01). However, there was no significant difference in it between smokers without lung cancer and healthy nonsmokers (P >0.05). Conclusion: These findings suggest that smoking may

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