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21.
Background:Prior reports have suggested that the red blood cell distribution width (RDW) parameter could be measured as a prognostic indicator in pulmonary embolism (PE) patients, thereby helping to guide their care. However, no systematic analyses on this topic have been completed to date, and the exact relationship between RDW and PE remains to be fully clarified. We will therefore conduct a systematic literature review with the goal of defining the correlation between RDW and mortality in acute PE cases.Methods:The EMBASE, Web of Knowledge, PubMed, ClinicalTrials.gov, and Cochrane Library databases will be searched for all relevant studies published from inception through March 2021 using the following search strategy: (“red blood cell distribution width”) AND (“pulmonary embolism”). Two authors will independently identify eligible studies and extract data. The Q and I2 statistics will be used to judge heterogeneity among studies.Results:This study will establish the relative efficacy of RDW as a metric for predicting PE patient mortality.Conclusions:This study will offer a reliable, evidence-based foundation for the clinical utilization of RDW as a tool for gauging mortality risk in acute PE patients.Ethics and dissemination:As this is a protocol for a systematic review of previously published data, no ethical approval is required. Electronic dissemination of study results will be done through a peer-review publication or represented at a related conference.  相似文献   
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Clinical Rheumatology - Intra-articular corticosteroid injection (IACI) is generally used in the management of juvenile idiopathic arthritis (JIA) to obtain rapid relief of active synovitis and...  相似文献   
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Glomerular hyperfiltration and microalbuminuria/proteinuria are early manifestations of sickle nephropathy. The effects of hydroxyurea therapy on these renal manifestations of sickle cell anemia (SCA) are not well defined. Our objective was to investigate the effects of hydroxyurea on glomerular filtration rate (GFR) measured by 99mTc‐DTPA clearance, and on microalbuminuria/proteinuria in children with SCA. Hydroxyurea study of long‐term effects (HUSTLE) is a prospective study (NCT00305175) with the goal of describing the long‐term cellular, molecular, and clinical effects of hydroxyurea therapy in SCA. Glomerular filtration rate, urine microalbumin, and serum cystatin C were measured before initiating hydroxyurea therapy and then repeated after 3 years. Baseline and Year 3 values for HUSTLE subjects were compared using the Wilcoxon Signed Rank test. Associations between continuous variables were evaluated using Spearman correlation coefficient. Twenty‐three children with SCA (median age 7.5 years, range, 2.5–14.0 years) received hydroxyurea at maximum tolerated dose (MTD, 24.4 ± 4.5 mg/kg/day, range, 15.3–30.6 mg/kg/day). After 3 years of treatment, GFR measured by 99mTc‐DTPA decreased significantly from 167 ± 46 mL/min/1.73 m2 to 145 ± 27 mL/min/1.73 m2 (P = 0.016). This decrease in GFR was significantly associated with increase in fetal hemoglobin (P = 0.042) and decrease in lactate dehydrogenase levels (P = 0.035). Urine microalbumin and cystatin C levels did not change significantly. Hydroxyurea at MTD is associated with a decrease in hyperfiltration in young children with SCA. Am. J. Hematol., 88:116–119, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Modulation of megakaryocytopoiesis by thrombopoietin: the c-Mpl ligand   总被引:2,自引:1,他引:2  
Banu  N; Wang  JF; Deng  B; Groopman  JE; Avraham  H 《Blood》1995,86(4):1331-1338
We have further characterized the biological activities, mechanism of action, and target cell populations of recombinant human and murine thrombopoietin (rhTPO and rmTPO) in in vitro human and murine model systems. Alone, hTPO or mTPO stimulated the maturation of immature murine megakaryoblasts as measured in a single cell assay. The combination of hTPO or mTPO and interleukin-6 (IL-6) resulted in a further increase in megakaryocyte differentiation in this system. Murine TPO stimulated mouse megakaryocyte progenitor development. Human megakaryocyte progenitor development was potentiated by hTPO alone and further augmented in the presence of the early-acting cytokines (IL-3) or kit ligand/stem cell factor (KL/SCF). To further define the mechanism of action of TPO, neutralization studies were performed with antisera to IL-3, granulocyte-macrophage colony-stimulating factor (GM- CSF), IL-1 beta, and IL-11. No diminution in TPO activity was observed in the presence of these antisera. Moreover, because adhesive interactions are known to modulate hematopoiesis, we studied whether hTPO might alter such interactions between human bone marrow (BM) megakaryocytes and human BM stromal fibroblasts. No changes were observed in either megakaryocyte expression of the surface molecules lymphocyte function-associated antigen-1, very late activation antigen- 4, or intercellular adhesion molecule-1 or the adhesion of megakaryocytes to stromal fibroblasts after treatment with the growth factor. Furthermore, no induction of secretion of the cytokines IL-1 alpha, IL-1 beta, GM-CSF, IL-6, granulocyte-CSF, tumor necrosis factor- alpha, transforming growth factor-beta 1, or transforming growth factor- beta 2 by primary human BM megakaryocytes was noted after treatment of the cells with hTPO. To address whether TPO affects very primitive hematopoietic progenitors, we studied the residual cells from the BMs of mice treated with high doses of 5-fluorouracil. Although no effect of mTPO alone was noted on the viability or replication of such primitive murine progenitor populations, the triple combination of IL-3 + KL/SCF + TPO stimulated growth of megakaryocyte progenitors. These results indicate that TPO is a highly lineage-specific growth factor whose primary biological effects are likely to be direct modulation of the growth and maturation of committed megakaryocyte precursors and immature megakaryoblasts.  相似文献   
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It is frequent to see pulmonary hypertension (PH) in patients with mitral stenosis (MS) secondary to increased pulmonary vascular resistance (PVR), data about the effect of PVR on the results of percutaneous balloon mitral valvotomy (PBMV) are insufficient. To detect the role of PVR in predicting residual PH immediately after PBMV. This prospective study comprised 49 consecutive patients with moderate to severe MS who were investigated pre and within 48 h post a successful PBMV for the first time. Echocardiography was used to assess the mitral valve area (MVA), mean transmitral pressure gradient (MPG), mitral valve resistance (MVR), right ventricular systolic pressure (RVSP) and PVR. Patients were classified into two groups according to the pre PVR (≥?1.6 WU as group I and < 1.6 as group II). At baseline compared to group II (32 patients), Group I (17 patients) had higher MPG (13.6?±?5.2 vs. 11.7?±?3.7 mmHg, P?<?0.05), RVSP (45.6 vs. 37.9 mmHg, P?<?0.001) and PVR (2.2?±?0.1 vs. 1.2?±?0.1WU, P?<?0.001) with no significant difference regarding age, gender, MVS, MVA and MVR. Patients of group I had comparatively lower improvement immediate post procedural of RVSP and PVR with no significant difference in immediate post procedural improvement in NYHA classification, MVA, MPG and MVR. Basal PVR?>?1.8WU was proved to be a highly specific (91%), a good predictor (AUC 0.78) of persistent elevation of RVSP?>?50 mmHg post PMV. Pathological rise of PVR that associates MS had provided a strong and an independent predictor of persistent pulmonary hypertension post PBMV and by this aspect it could be used as a valuable tool as MVA and MPG to send patients earlier for PBMV even with less severe MS. PVR?>?1.81 WU could be used as a noninvasive parameter for predicting regression of PH immediately after PBMV.  相似文献   
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AIM:To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy (IVCM) in patients with keratoconus and control subjects.METHODS: Unscarred corneas of 78 keratoconic subjects without a history of contact lens use and 36 age-matched control subjects were evaluated with slit-lamp examination (SLE), corneal topography and laser scanning IVCM. One eye was randomly chosen for analysis. Anterior and posterior stromal keratocyte, endothelial cell and basal epithelial cell densities and sub-basal nerve structure were evaluated.RESULTS: IVCM qualitatively demonstrated enlarged basal epithelial cells, structural changes in sub-basal and stromal nerve fibers, abnormal stromal keratocytes and keratocyte nuclei, and pleomorphism and enlargement of endothelial cells. Compared with control subjects, significant reductions in basal epithelial cell density (5817±306 cells/mm2 vs 4802±508 cells/mm2, P<0.001), anterior stromal keratocyte density (800±111 cells/mm2 vs 555±115 cells/mm2, P<0.001), posterior stromal keratocyte density (333±34 cells/mm2 vs 270±47 cells/mm2, P<0.001), endothelial cell density (2875±223 cells/mm2 vs 2686±265 cells/mm2, P<0.001), sub-basal nerve fiber density (31.2±8.4 nerves/mm2 vs 18.1±9.2 nerves/mm2, P<0.001), sub-basal nerve fiber length (21.4±3.4 mm/mm2 vs 16.1±5.1 mm/mm2, P<0.001), and sub-basal nerve branch density (median 50.0 (first quartile 31.2 - third quartile 68.7) nerve branches/mm2 vs median 25.0 (first quartile 6.2 - third quartile 45.3) nerve branches/mm2, P<0.001) were observed in patients with keratoconus.CONCLUSION: Significant microstructural abnormalities were identified in all corneal layers in the eyes of subjects with keratoconus using IVCM. This non-invasive in vivo technique provides an important means to define and follow progress of microstructural changes in patients with keratoconus.  相似文献   
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Clinical Rheumatology - Autoimmune pancreatitis (AIP) type 1 is an IgG4-related disease (IgG4-RD), characterized by inflammatory pseudotumors and histologically by dense lymphoplasmacytic...  相似文献   
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Clinical Rheumatology - The aim of this study was to evaluate the relationships among the disease activity, illness perception, daily life performance, anxiety and depression status as potential...  相似文献   
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