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排序方式: 共有905条查询结果,搜索用时 46 毫秒
831.
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833.
I Kronzon P A Tunick A Goldfarb R S Freedberg L Chinitz J Slater M E Schwinger A J Gindea E Glassman W G Daniel 《Journal of the American Society of Echocardiography》1990,3(1):64-71
Twenty-nine patients were studied by pulsed, continuous wave, and color Doppler before and after percutaneous transseptal valvuloplasty. New atrial septal defects were detected in 14 patients, and the patients were monitored for up to 320 days after the procedure. The diameter of the defect, best evaluated by the transesophageal approach, was 3 to 15 mm. A narrow, high velocity (1.4 to 3.1 meters per second) left-to-right shunt jet was detected in 13 of 14 patients. The shunt jet was continuous in nine of 14 patients, late systolic-holodiastolic in four patients, and bidirectional in one patient. Cardiac catheterization in nine patients confirmed the Doppler findings and demonstrated a peak pressure gradient of 10 to 32 mm Hg between the left and right atria. Oximetry revealed a calculated pulmonary to systemic flow ratio ranging from 2.3:1 in the patient with the largest atrial septal defect by echocardiography to 1:1 (no oxygen saturation step-up) in the patient with the smallest atrial septal defect. In the three patients who underwent cardiac surgery, the operative findings confirmed those of echocardiography. We concluded that atrial septal defects are common after transseptal valvuloplasty. Usually, their relatively small size and the underlying valvular disease that produces high left atrial pressure are responsible for the high pressure gradient between the left and right atria. This results in the high velocity and continuous shunt jet detected by Doppler echocardiography. 相似文献
834.
835.
836.
Jin Z Bohach GA Shiloach J Norris SE Freedberg DI Deobald C Coxon B Robbins JB Schneerson R 《Infection and immunity》2005,73(12):7887-7893
Neisseria meningitidis groups A (GAM) and W135 capsular polysaccharides (CPs) were bound to recombinant Staphylococcus aureus enterotoxin C1 (rSEC). The CPs were activated with 1-cyano-4-dimethylaminopyridinium tetrafluoroborate and then bound to adipic acid dihydrazide derivatives of rSEC. Syntheses were conducted with native GAM CP (GAMP), W135 CP (W135P), and ultrasonicated or hydrazine-treated W135P at various concentrations of reactants, pHs, and ionic strengths. The conjugates were characterized by compositional and serologic analyses, high-performance size-exclusion chromatography with multi-angle laser light scattering detection, and immunogenicity in 5- to 6-week-old mice. Conjugates injected subcutaneously in phosphate-buffered saline elicited immunoglobulin G (IgG) responses against their respective CPs and rSEC, whereas GAMP and W135P alone did not induce detectable CP antibodies. The O-acetyl content of W135P was low, and its removal had no adverse effect upon the conjugate's immunogenicity. Reduction of the molecular size of W135P by treatment with hydrazine improved the immunogenicity of W135P-rSEC. IgG anti-CP elicited by the conjugates showed complement-dependent bactericidal activity against their respective organisms, and IgG anti-rSEC neutralized the T-cell proliferative activity of native SEC. A bivalent formulation of GAMP-rSEC and W135P-rSEC elicited IgG anti-CP at comparable levels to those induced by the conjugates administered separately. 相似文献
837.
Antonelli D Freedberg NA Rosenfeld T 《Pacing and clinical electrophysiology : PACE》2004,27(5):692-692
We report a case of unsuccessful rescrewing of an atrial lead after its early dislodgment in a 64 years old patient because of entrapped endocardial tissue in the screw-in system. (PACE 2004; 27:692) 相似文献
838.
839.
Hanslik T Boëlle PY Schwarzinger M Carrat F Freedberg KA Valleron AJ Flahault A 《Vaccine》2003,21(25-26):3614-3622
Age-specific force of varicella infection, hospitalisation and death rates in non-immune persons were calculated using an age-based mathematical model and national data for France. A cost-effectiveness model was then applied to hypothetical cohorts of persons aged 15-45 years with a negative or uncertain history of varicella. Vaccination strategies with and without prior serotesting, and healthcare payer perspective and societal perspective were considered. A sensitivity analysis was performed. Vaccination prevented more than one third of all varicella-related deaths. With serotesting, compared with no intervention, the cost per case avoided and per year of life saved for subjects aged 15 years were 335 and 55,100 Euro, respectively. When work-loss costs were also included, savings were associated with screening and vaccination of subjects less than 30 years old. Without serotesting, the costs raised markedly, with an almost identical effectiveness, resulting in an unfavourable incremental cost-effectiveness. Based on medical costs, routine serotesting and varicella vaccination for French adolescents and young adults with a negative or uncertain history of varicella affords health benefits at a cost comparable to those of other very expensive therapies considered worthwhile. From the societal perspective, such screening and vaccination might save costs. 相似文献
840.
ABSTRACT. Urinary total protein excretion and the pattern of urinary proteins-one of which was haemoglobin-has been determined in 9 newborns suffering from haemolytic anaemia and hyperbilirubinaemia due to anti-D isoimmunization and in 10 healthy newborns. Eight of the 9 newborns with erythroblastosis fetalis showed elevated urinary total protein excretion and augmented haemoglobinuria. The possible toxic effect of the haemoglobinuria and hyperbilirubinaemia on the tubular functions is discussed. 相似文献