Objective To investigate the resistance of Helicobacter pylori (H. pylori) strains to common antibiotics and to analyze the sites of genetic mutations carried by clarithromycin-resistant strains in order to provide reference for selecting sensitive antibiotics against H. pylori and for providing individualized treatment for patients in Changchun area. Methods Drug resistance of H. pylori clinical isolates to common antibiotics was detected by disk dilution method. The 23S rRNA genes of clarithromycin-resistant strains were amplified by PCR and then sequenced to analyze the presence of mutations. Results In this study, 69 strains of H. pylori were successfully isolated with a positive rate of 23. 1％ . Results of the drug susceptibility test to seven commonly used antibiotics showed that there were 52. 2％ of the isolates resistant to clarithromy-cin, 47. 8％ to tinidazole, 37. 7％ to levofloxacin, 33. 3％ to tetracycline hydrochloride, 30. 4％ to furazoli-done, 30. 4％ to metronidazole and 5. 8％ to amoxicillin. Amoxicillin could continue to be used as a first-line antimicrobial agent. Seven mutation sites were found in the 23S rRNA genes carried by the clarithromy-cin-resistant strains, which were A1821G, G1826A, T1830C, G1940A, A2143G, T2182C and A2223G. The A2143G site mutation accounted for 54. 2％ and was the predominant mutation resulting in the resistance to clarithromycin of H. pylori strains circulating in this area. Conclusions The H. pylori strains isolated from patients with gastroduodenal diseases in Changchun area had a high resistance rate to clarithromycin, which was mainly caused by the A2143G mutation in 23S rRNA gene.

Objective To observe the value of multimodal imaging for diagnosis of cardiac space-occupying lesions.Methods Data of 70 patients with cardiac space-occupying lesions who underwent echocardiography and cardiac CT(CCT)were retrospectively analyzed,among them 35 also underwent cardiac MRI(CMRI).The value of multimodal imaging for diagnosis of cardiac space-occupying lesions were explored according to the results of surgical pathology or clinical diagnosis.Results Among 70 cases,benign tumors were confirmed by surgical pathology in 43 cases,while malignant tumors were confirmed by surgical pathology in 3 cases and clinically diagnosed in 1 case.Meanwhile,non-tumor-occupying lesions were clinically diagnosed in 23 cases,all obviously shrunken after treatments.Among 70 cases,echocardiography correctly diagnosed 57 cases,misdiagnosed 8 cases and unclearly diagnosed 5 cases,with diagnostic accuracy rate of 81.43%(57/70).CCT correctly diagnosed 63 cases,misdiagnosed 4 cases but missed 3 cases,with diagnostic accuracy rate of 90.00%(63/70).CMRI outcomes in all 35 cases were consistent with surgical pathologic results,with diagnostic accuracy rate of 100%(35/35).Conclusion Multimodal imaging might provide objective evidences for diagnosis and treatment of cardiac space-occupying lesions.