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排序方式: 共有1227条查询结果,搜索用时 26 毫秒
31.
Natasa Stanisavljevic L. Stojanovich D. Marisavljevic A. Djokovic V. Dopsaj J. Kotur-Stevuljevic J. Martinovic L. Memon S. Radovanovic B. Todic D. Lisulov 《Clinical rheumatology》2016,35(10):2485-2493
The aim of this study was to evaluate oxidative stress markers and it relations to endothelial damage as risk factor for thrombosis in patients with primary (PAPS) and secondary (SAPS) antiphospholipid syndrome (APS) in correlation to traditional risk factors. Flow-mediated (FMD) and nitroglycerine (NMD)-induced dilation of the brachial artery were studied in 140 APS patients (90 PAPS, 50 SAPS) and 40 controls matched by age, sex, and conventional risk factors for atherosclerosis. Markers of oxidative stress, lipid hydroperoxydes (LOOH), advanced oxidation protein products (AOPP), total sulfhydryl groups (tSHG), and paraoxonase 1 activity (PON1) were determined by spectrophotometric method. Oxidative stress dominates in APS patients. LOOH and AOPP correlate to lipid fractions (p < 0.05), unlike PON1, tSHG that correlated to antiphospholipid antibody positivity (p < 0.05). FMD was lower in APS patients comparing to controls (p < 0.001). Cholesterol is independent variable for FMD impairment in control group (p = 0.011); LOOH in PAPS (p = 0.004); LOOH, aCL, and triglycerides in SAPS patients (p = 0.009, p = 0.049, and p = 0.012, respectively). Combined predictive of aCL and LOOH is better for FMD impairment than LOOH alone in both PAPS and SAPS patients (AUC 0.727, p = 0.001, 95 % CI 0.616–0.837 and AUC 0.824, p?0.001, 95 % CI 0.690–0.957, respectively). Lipid peroxidation is independent predictor for endothelial dysfunction in APS patients. We demonstrated synergistic effect of aCL and LOOH as risk for endothelial impairment in both PAPS and SAPS patients. 相似文献
32.
Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL 总被引:1,自引:1,他引:1
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states. 相似文献
33.
In vivo expression of the B7 costimulatory molecule by subsets of antigen-presenting cells and the malignant cells of Hodgkin's disease 总被引:10,自引:0,他引:10
Munro JM; Freedman AS; Aster JC; Gribben JG; Lee NC; Rhynhart KK; Banchereau J; Nadler LM 《Blood》1994,83(3):793-798
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites. 相似文献
34.
O'Day SJ; Rabinowe SN; Neuberg D; Freedman AS; Soiffer RJ; Spector NA; Robertson MJ; Anderson K; Whelan M; Pesek K 《Blood》1994,83(9):2707-2714
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity. 相似文献
35.
KA Hodgkinson SP Connors N Merner A Haywood T‐L Young WJ McKenna B Gallagher F Curtis AS Bassett PS Parfrey 《Clinical genetics》2013,83(4):321-331
To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility. 相似文献
36.
37.
Memon A Bartlett J Rose R Gray C 《The journals of gerontology. Series B, Psychological sciences and social sciences》2003,58(6):P338-P345
As a way to examine the nature of age-related differences in lineup identification accuracy, young (16-33 years) and older (60-82 years) witnesses viewed two similar videotaped incidents, one involving a young perpetrator and the other involving an older perpetrator. The incidents were followed by two separate lineups, one for the younger perpetrator and one for the older perpetrator. When the test delay was short (35 min), the young and older witnesses performed similarly on the lineups, but when the tests were delayed by 1 week, the older witnesses were substantially less accurate. When the target was absent from the lineups, the older witnesses made more false alarm errors, particularly when the faces were young. When the target was present in the lineups, correct identifications by both young and older witnesses were positively correlated with a measure of source recollection derived from a separate face-recognition task. Older witnesses scored poorly on this measure, suggesting that source-recollection deficits are partially responsible for age-related differences in performance on the lineup task. 相似文献
38.
39.
Tyndall SH Memon MA Lund RJ Beck D Fessenden J Stegman MR Fitzgibbons RJ 《European journal of gastroenterology & hepatology》1999,11(12):1359-1364
OBJECTIVE: To determine if the size of the gastrojejunal anastomosis after Billroth II reconstruction was the rate-limiting factor in gastric emptying in the postoperative period. METHODS: Twelve mongrel dogs were randomized to have either 1.5 cm or 5 cm gastrojejunal anastomoses prior to Billroth II hemigastrectomy. Each dog had three solid and three liquid radiolabelled emptying studies pre- and postoperatively. Data were collected using a gamma camera. For liquid studies, images were obtained at 0 min, 2 min, 4 min, 6 min, 8 min, 10 min, 20 min, 30 min, 40 min, 50 min and 60 min. For solid studies, images were obtained at 0 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min and 120 min. Means were compared by analysis of variance using the repeated measures option. RESULTS: Postoperative liquid emptying was significantly faster in the first 10 min with both 1.5 cm and 5 cm anastomoses compared with preoperative scans in the same animals (45% versus 20% and 48% versus 29%, respectively). On the other hand, solid gastric emptying was much slower postoperatively with the 1.5 cm anastomosis compared with preoperative scans (29% versus 65%) as well as compared with postoperative 5 cm anastomosis (29% versus 62%) at the end of 120 min. CONCLUSIONS: Our model suggests that the gastric emptying of solids is affected by the size of the gastrojejunal anastomosis and not by the diameter of the efferent limb of the small intestine following Billroth II reconstruction. 相似文献
40.
In this research, structural-functional integrated cement-based materials were prepared by employing cement paste and a microencapsulated phase change material (MPCM) manufactured using urea-formaldehyde resin as the shell and paraffin as the core material. The encapsulation ratio of the MPCM could reach up to 91.21 wt%. Thermal energy storage cement pastes (TESCPs) incorporated with different MPCM contents (5%, 10%, 15%, 20% and 25% by weight of cement) were developed, and their thermal and mechanical properties were studied. The results showed that the total energy storage capacity of the hardened cement specimens with MPCM increased by up to 3.9-times compared with that of the control cement paste. The thermal conductivity at different temperature levels (35–36 °C, 55–56 °C and 72–74 °C) decreased with the increase of MPCM content, and the decrease was the highest when the temperature level was 55–56 °C. Moreover, the compressive strength, flexural strength and density of hardened cement paste decreased with the increase in MPCM content linearly. Among the evaluated properties, the compressive strength of TESCPs had a larger and faster degradation with the increase of MPCM content. 相似文献