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101.
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Hua Zhang PhD Shaodong Qiu BD Fei Chen PhD Zhimin Zhu MD 《Journal of clinical ultrasound : JCU》2019,47(7):412-418
Because of better awareness and understanding of its pathophysiology, the cardiorenal syndrome (CRS) is more often diagnosed and better managed. The echocardiographic evaluation of CRS now benefits from three-dimensional speckle tracking echocardiography (3D-STE), which allows multidimensional and real-time evaluation of regional myocardial and overall cardiac function, and helps assessing the degree of myocardial damage. This article describes the application of 3D-STE in evaluating the myocardial motion in patients with CRS. 相似文献
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A S Freedman J M Munro K Rhynhart P Schow J Daley N Lee J Svahn L Eliseo L M Nadler 《Blood》1992,80(5):1284-1288
In germinal centers, B lymphocytes are intimately associated with follicular dendritic cells (FDCs). It has been hypothesized that FDCs are involved in the regulation of B-cell growth and differentiation through cell-cell interactions. In this study, highly enriched preparations of FDCs were isolated by cell sorting using the FDC restricted monoclonal antibody DRC-1. When irradiated FDCs were cultured with mitogen stimulated B cells, B cell 3H-TdR uptake was inhibited by up to 80%. This inhibitory effect was not seen when paraformaldehyde fixed FDCs were added to B-cell cultures, suggesting that the FDCs needed to be metabolically active. Moreover, supernatants from cultured FDCs were similarly able to inhibit B-cell proliferation. These results demonstrate that FDCs may downregulate the clonal expansion of B cells that occurs within lymphoid follicles as part of the normal physiologic immune response. Potentially, the loss of the inhibitory role of FDCs in vivo may be of importance in certain infectious and neoplastic processes in which germinal centers are affected. 相似文献
104.
Mariana Murea Leon Lenchik Thomas C. Register Gregory B. Russell Jianzhao Xu S. Carrie Smith Donald W. Bowden Jasmin Divers Barry I. Freedman 《Journal of diabetes and its complications》2018,32(6):558-564
Aim
Recent studies revealed a correlation between skeletal muscle mass index and density with longevity; these studies largely evaluated appendicular skeletal muscles in older Caucasians. This retrospective cohort study assessed the association between axial skeletal muscles size and density with survival in African Americans with type 2 diabetes mellitus.Methods
Psoas and paraspinous muscle mass index (cross sectional area/height2) and radiographic density (in Hounsfield Units) were measured using computed tomography in African American-Diabetes Heart Study participants, 314 women and 256 men, with median (25th, 75th quartile) age 55.0(48.0, 62.0) and 57.0(50.0, 64.0) years, respectively. Covariates in fully-adjusted model included age, sex, BMI, smoking, hormone replacement therapy (women), cardiovascular disease, hypertension, coronary artery calcified plaque mass, carotid artery calcified plaque mass, and African ancestry proportion.Results
After median of 7.1(5.9, 8.2) years follow-up, 30(9.6%) of women and 49(19.1%) of men were deceased. In fully-adjusted models, psoas muscle mass index and paraspinous muscle mass index were inversely associated with mortality in men (psoas muscle mass index, hazard ratio [HR]?=?0.61, P?=?0.004; paraspinous muscle mass index, HR?=?0.64, P?=?0.004), but not in women. Psoas and paraspinous muscle densities did not associate with all-cause mortality. A penalized Cox regression that involved all covariates and predictors associated with mortality showed that only paraspinous muscle mass index remained a significant predictor of mortality (HR =?0.65, P?=?0.02).Conclusion
Independent from established risk factors for mortality, higher psoas and paraspinous muscle index associate with reduced all-cause mortality in middle-aged African American men with type 2 diabetes mellitus. 相似文献105.
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone. 相似文献
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Mark S. Freedman Nicola De Stefano Frederik Barkhof Chris H. Polman Giancarlo Comi Bernard M. J. Uitdehaag Florence Casset-Semanaz Brian Hennessy Lorenz Lehr Bettina Stubinski Dominic L. Jack Ludwig Kappos 《Journal of neurology》2014,261(3):490-499
The REFLEX study (NCT00404352) established that subcutaneous (sc) interferon (IFN) β-1a reduced the risks of McDonald MS (2005 criteria) and clinically definite multiple sclerosis (CDMS) in patients with a first clinical demyelinating event suggestive of MS. The aim of this subgroup analysis was to assess the treatment effect of sc IFN β-1a in patient subgroups defined by baseline disease and demographic characteristics (age, sex, use of steroids at the first event, classification of first event as mono- or multifocal, presence/absence of gadolinium-enhancing lesions, count of <9 or ≥9 T2 lesions), and by diagnosis of MS using the revised McDonald 2010 MS criteria. Patients were randomized to the serum-free formulation of IFN β-1a, 44 μg sc three times weekly or once weekly, or placebo, for 24 months or until diagnosis of CDMS. Treatment effects of sc IFN β-1a on McDonald 2005 MS and CDMS in the predefined subgroups were similar to effects found in the intent-to-treat population. McDonald 2010 MS was retrospectively diagnosed in 37.7 % of patients at baseline. Both regimens of sc IFN β-1a significantly reduced the risk versus placebo of McDonald 2005 MS and CDMS, irrespective of McDonald 2010 status at baseline (risk reductions between 29 and 51 %). The effect of sc IFN β-1a was not substantially influenced by baseline patient demographic and disease characteristics, or baseline presence/absence of McDonald 2010 MS. 相似文献
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