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101.
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The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
104.
Spindle-cell adenomyoepithelioma of the breast. A microscopic, ultrastructural, and immunocytochemical study 总被引:1,自引:0,他引:1
Two patients developed nodular, well-circumscribed tumors of the breast, discovered by mammography. They were fibroadenoma-like by gross examination and biphasic by light microscopy, containing both tubular glands and spindled myoid cells. Immunocytochemical studies revealed cytokeratin and S-100 immunoreactivity in both the spindled myoid cells and in the tubuloglandular cells (S-100 was focal in the latter). In addition, the spindled myoid cells were immunoreactive for vimentin but negative for desmin. Ultrastructural studies showed the tubular glands to be composed of luminal epithelial cells focally surrounded by myoepithelial cells, but the stroma contained spindled myoepithelial cells admixed with occasional fibroblasts. The diagnostic term, "adenomyoepithelioma," is appropriate for biphasic tumors having both glandular and myoepitheliomatous differentiation. Although additional experience is necessary to be conclusive regarding the biologic behavior of these unusual lesions, the authors believe the adenomyoepitheliomas described here are benign. They were well circumscribed without invasion of adjacent breast, contained neither mitotic figures nor cytologic atypia, and have not recurred or metastasized (6 and 10 months after removal). 相似文献
105.
Pressure recovery distal to a stenosis: potential cause of gradient "overestimation" by Doppler echocardiography 总被引:1,自引:0,他引:1
R A Levine A Jimoh E G Cape S McMillan A P Yoganathan A E Weyman 《Journal of the American College of Cardiology》1989,13(3):706-715
Doppler ultrasound is currently being widely applied to measure intracardiac pressure gradients noninvasively. In comparative invasive studies, it is generally assumed that pressure is effectively uniform distal to the stenosis. As the poststenotic jet expands, however, its velocity decreases, and pressure is recovered to the extent permitted by turbulence, so that the measured gradient will be lower if the distal catheter is positioned downstream from the vena contracta. This can lead to apparent Doppler "overestimation" of the pressure gradient because of this phenomenon of pressure recovery. This study demonstrates that pressure recovery can be important in a variety of clinical settings studied by in vitro models. Although most prominent in streamlined tunnels modeled after the obstruction in patients with hypertrophic cardiomyopathy, these effects are important even for central stenoses at physiologic flow rates. Because precise catheter position is not always known or controlled, these findings suggest an important advantage for Doppler gradient estimation, because it provides the maximal gradient at the vena contracta, which determines the load on the proximal chamber. 相似文献
106.
Safety and immune responses to attenuated Salmonella enterica serovar typhi oral live vector vaccines expressing tetanus toxin fragment C 总被引:1,自引:0,他引:1
Tacket CO Galen J Sztein MB Losonsky G Wyant TL Nataro J Wasserman SS Edelman R Chatfield S Dougan G Levine MM 《Clinical immunology (Orlando, Fla.)》2000,97(2):146-153
Attenuated Salmonella enterica serovar Typhi vaccine strain CVD 908-htrA was used as a vector to deliver fragment C of tetanus toxin as a single-dose oral tetanus vaccine candidate to elicit protective levels of serum tetanus antitoxin. Twenty-one healthy adult volunteers received doses of 1.6 x 10(7) to 8.2 x 10(9) CFU of one of two strains, CVD 908-htrA(pTETnir15) or CVD 908-htrA(pTETlpp), which contained plasmid-encoded fragment C, with sodium bicarbonate, and the safety and immune responses to serovar Typhi antigens and tetanus toxin were assessed. No volunteer had fever or positive blood cultures after vaccination, although diarrhea occurred in 3 volunteers and vomiting in 2 volunteers within 3 weeks after vaccination. Most volunteers excreted the vaccine strain in the first 72 h after vaccination. Three of nine volunteers who received 10(8) CFU or higher doses of the CVD 908-htrA(pTETlpp) construct developed rises in serum antitoxin antibodies. The serum and cellular immune responses to serovar Typhi antigens were less frequent than those previously observed in volunteers who ingested the parent strain CVD 908-htrA. This study demonstrates that fragment C of tetanus toxin delivered orally to volunteers in an S. Typhi vector can elicit protective levels of serum antitoxin. 相似文献
107.
An ideal vaccine has certain biological and physical characteristics. Technological advances have provided new strategies that may help the design of such a vaccine. 相似文献
108.
Husaini BA Sherkat DE Levine R Bragg R Van CA Emerson JS Mentes CM 《Journal of the National Medical Association》2002,94(2):100-106
This study examines the effectiveness of breast cancer screening education programs on mammography rates among African-American women 40 years of age and over. We conducted two types of educational programs in community settings, primarily in African-American churches. Three-month follow-up interviews were used to determine whether women who participated in programming were more likely to get a mammogram if they had not had a mammogram in the last year. Our results demonstrate that the educational programs significantly increased the likelihood of getting a mammogram when compared to a control group that received no educational programming. Further, we found that the programs were effective for motivating breast cancer screening in housing projects as well as in the churches, and that the effectiveness of the programs remained even when we controlled for socioeconomic status, depression, and age. 相似文献
109.
110.
Molecular epidemiologic studies of polycyclic aromatic hydrocarbon-DNA adducts and breast cancer 总被引:3,自引:0,他引:3
Rundle A Tang D Hibshoosh H Schnabel F Kelly A Levine R Zhou J Link B Perera F 《Environmental and molecular mutagenesis》2002,39(2-3):201-207
We review our studies on the role of polycyclic aromatic hydrocarbon (PAH)-DNA adducts in breast cancer. Additionally we report on analyses of the reliability of the scoring procedures used with immunohistochemical assay for PAH-DNA adducts and of potential bias arising from the use of benign breast disease (BBD) controls. We conducted a case-control study utilizing two control groups: BBD controls who donated tissue and blood samples, and healthy controls who donated blood samples. In comparisons of tumor tissue from cases and benign tissue from BBD controls, increasing adduct levels were significantly associated with case-control status [odds ratio (OR) = 2.40, 95% confidence interval (CI) 1.18-4.92], whereas in comparisons of nontumor tissue from cases and benign tissue from BBD controls the association was nonsignificant (OR = 1.97, 95% CI 0.94-4.17). We also show among cases, but not among BBD controls, that the GSTM1 null genotype is associated with increased adduct levels in breast tissue. Our reliability study found the scoring procedures used with the immunohistochemical assay to have high reliability, 0.93 in nontumor, 0.82 in tumor, and 0.74 in benign tissues. However, we found that the technician significantly contributed to the total variability of a series of data. Finally, we did not find a consistent bias to the null associated with the use of BBD controls; however, BBD controls may overestimate the prevalence of family history of breast cancer compared to that of healthy controls (18% vs.14%). We hypothesize that the higher prevalence results from a referral bias and discuss how this may influence our results. 相似文献