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排序方式: 共有3390条查询结果,搜索用时 15 毫秒
51.
Felmeden DC Spencer CG Chung NA Belgore FM Blann AD Beevers DG Lip GY 《The American journal of cardiology》2003,92(4):400-405
Increasing evidence points toward a prothrombotic state in hypertension and atherosclerosis, conditions associated with thrombosis-related complications, such as myocardial infarction and stroke. We hypothesized that this increased risk of thrombogenesis may be related to endothelial damage/dysfunction and abnormal angiogenesis, and thus, an increased risk of future cardiovascular disease. Thrombogenesis, endothelial damage/dysfunction, and angiogenesis can be assessed by measurement of tissue factor (TF), von Willebrand Factor (vWF), flow-mediated dilatation (FMD), and vascular endothelial growth factor (VEGF), respectively. To test this hypothesis, we measured TF, vWF, FMD, and VEGF in 76 patients with systemic hypertension (71 men; mean age 64; mean blood pressure 167/72 mm Hg), considered additional risk factors such as diabetes, and related them to the patient's 10-year cardiovascular and cerebrovascular risk score using the Framingham equation. Patients were compared with 48 healthy normotensive controls. In these patients, the effects of 6 months of intensified blood pressure and (where appropriate) lipid-lowering treatment were investigated. In our patients, TF, VEGF, and vWF levels were higher, but FMD was lower (all p <0.001) compared with the controls. All markers correlated with each other and with both cardiovascular and cerebrovascular risk scores (all p <0.001). After intensified blood pressure and hypercholesterolemia treatment, total cholesterol, blood pressure, TF, VEGF, and vWF levels all decreased, whereas FMD increased (all p <0.001). Thus, in subjects with hypertension and other risk factors, endothelial damage/dysfunction (and thus, atherogenesis), thrombogenesis, and angiogenesis are abnormal, correlate with overall cardiovascular risk, and importantly, can be related to each other in a "Birmingham Vascular Triangle." Furthermore, these processes are beneficially affected by intensive blood pressure and lipid treatment. 相似文献
52.
Germinal center phenotype and bcl-2 expression combined with the International Prognostic Index improves patient risk stratification in diffuse large B-cell lymphoma 总被引:15,自引:9,他引:15
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Barrans SL Carter I Owen RG Davies FE Patmore RD Haynes AP Morgan GJ Jack AS 《Blood》2002,99(4):1136-1143
The International Prognostic Index (IPI) identifies poor- and good-risk patients with diffuse large B cell lymphoma (DLBCL); however, the majority of patients have an intermediate IPI, with an uncertain prognosis. To determine whether cellular factors can be combined with the IPI to more accurately predict outcome, we have analyzed 177 presentation nodal DLBCLs for the expression of bcl-2 and a germinal center (GC) phenotype (defined by expression of bcl-6 and CD10). P53 gene band shifts were detected using single-stranded conformational polymorphism polymerase chain reaction analysis of exons 5-9 and were correlated with protein expression. In a Cox regression analysis, IPI (R = 0.22, P <.0001) and bcl-2 (R = 0.14, P =.0001) were independent poor prognostic factors and a GC phenotype predicted a favorable outcome (R = -0.025, P =.02). Neither p53 expression nor band shifts had a significant effect on survival. Using the IPI alone, 8% of patients were identified as high risk. Expression of bcl-2 in the intermediate IPI group identified a further 28% of patients with an overall survival comparable to the high IPI group. In the intermediate IPI, bcl-2(-) group, the presence of a GC phenotype improved overall survival to levels approaching the IPI low group. Following this analysis only 15% of patients failed to be assigned to a favorable- or poor-risk group. Sequential addition of bcl-2 expression and GC phenotype into the IPI significantly improves risk stratification in DLBCL. For the 36% of high-risk patients with a 2-year overall survival of 19%, alternative treatment strategies should be considered in future trials. 相似文献
53.
Colovesical fistulae typically present with pneumaturia and/or fecaluria. Diverticulitis, inflammatory bowel disease, and malignancies of the colon are the commonest causes. The fistulous tract and adjacent organs are best demonstrated by contrast‐enhanced CT scan with rectal contrast or MRI. Biopsy at cystoscopy/colonoscopy is necessary for complete evaluation and treatment planning. 相似文献
54.
Angelo DAlessandro Xiaoyun Fu Tamir Kanias Julie A. Reisz Rachel Culp-Hill Yuelong Guo Mark T. Gladwin Grier Page Steve Kleinman Marion Lanteri Mars Stone Michael P. Busch James C. Zimring 《Haematologica》2021,106(5):1290
Red blood cell (RBC) storage in the blood bank promotes the progressive accumulation of metabolic alterations that may ultimately impact the erythrocyte capacity to cope with oxidant stressors. However, the metabolic underpinnings of the capacity of RBC to resist oxidant stress and the potential impact of donor biology on this phenotype are not known. Within the framework of the REDS-III RBC-Omics study, RBC from 8,502 healthy blood donors were stored for 42 days and tested for their propensity to hemolyse following oxidant stress. A subset of extreme hemolysers donated a second unit of blood, which was stored for 10, 23, and 42 days and profiled again for oxidative hemolysis and metabolomics (599 samples). Alterations of RBC energy and redox homeostasis were noted in donors with high oxidative hemolysis. RBC from females, donors over 60 years old, donors of Asian/South Asian race-ethnicity, and RBC stored in additive solution- 3 were each independently characterized by improved antioxidant metabolism compared to, respectively, males, donors under 30 years old, Hispanic and African American race ethnicity donors, and RBC stored in additive solution-1. Merging metabolomics data with results from an independent genome-wide association study on the same cohort, we identified metabolic markers of hemolysis and glucose 6-phosphate dehydrogenasedeficiency, which were associated with extremes in oxidative hemolysis and dysregulation in nicotinamide adenine dinucleotide phosphate and glutathione- dependent detoxification pathways of oxidized lipids. Donor sex, age, ethnicity, additive solution and glucose 6-phosphate dehydrogenase status impact the metabolism of the stored erythrocyte and its susceptibility to hemolysis following oxidative insults. 相似文献
55.
We assessed a rat model to evaluate the immunogenicity of Haemophilus influenzae type b (Hib) conjugate vaccines and the effect on Hib immunogenicity of combining 2 Hib vaccines (Hib-tetanus toxoid [TT]-A and Hib-TT-B) with diphtheria-TT-acellular pertussis (DTaP)(3) or DTaP(5)/inactivated poliovirus (IPV) vaccines. Rats were immunized subcutaneously with Hib alone or with Hib and DTaP-based vaccines; anti-Hib capsular polysaccharide IgG, poly-ribosyl-ribitol-phosphate (PRP), IgG subclass, and cellular immune responses were evaluated. Results showed a significant reduction in the antibody response to PRP when Hib-TT-A was administered in combination with DTaP(3) and showed changes in the anti-PRP IgG subclass distribution between the separate and combination groups. However, combining Hib-TT-B with DTaP(5)/IPV did not reduce the anti-PRP antibody response. These results suggest that the model can predict the effect of combined administration of Hib and DTaP vaccines on Hib immunogenicity and would be suitable for preclinical studies of mechanisms of interference in Hib/DTaP vaccines. 相似文献
56.
Chronic consumption of a high-palatable diet induces obesity and markedly impairs arterial relaxation. We have recently reported that endothelial function is only partially resorted after acute withdrawal of palatable diet. Therefore, this study was designed to investigate the effects of chronic withdrawal of high-palatable obesity-inducing diet on metabolic and vascular function in rats. Wistar rats were fed either standard laboratory chow throughout (controls) or given a highly-palatable diet (diet-fed) for 15 weeks; or fed the diet for 8 weeks and then returned to chow (diet-to-chow) for further 7 weeks before sacrifice. Diet-fed rats had higher body weight, fat mass, liver and heart weight than both chow-fed and diet-to-chow groups (P<0.01 for all). Compared with chow-fed and diet-to-chow groups, diet-fed rats had significantly raised fasting plasma levels of insulin, leptin and triglycerides levels (each +180%; P<0.0001), but not glucose or non-esterified fatty acids. There were no significant differences between any metabolic parameters between chow-fed and diet-to-chow groups. Mesenteric arteries showed no significant differences between any groups in KCl-induced tension generation, while diet-fed groups had significantly higher noradrenaline-induced vasoconstriction than both chow-fed and diet-to-chow groups. Maximum endothelial-dependent vasorelaxation responses to carbamylcholine (CCh) were significantly (by 23%; P<0.001) attenuated in the diet-fed group. This defect was abolished in the diet-to-chow group. There were no significant differences in endothelium-independent vasorelaxation responses to sodium nitroprusside between the three groups. In conclusion, palatable diet induces obesity and metabolic abnormalities as well as a marked endothelial dysfunction. These abnormalities are completely reversed by chronic withdrawal of the obesity-inducing high-palatable diet. 相似文献
57.
Nabila Seddiki Chansavath Phetsouphanh Sanjay Swaminathan Yin Xu Sudha Rao Jasmine Li Elissa L. Sutcliffe Gareth Denyer Robert Finlayson Linda Gelgor David A. Cooper John Zaunders Anthony D. Kelleher 《European journal of immunology》2013,43(2):510-520
The fine control of T‐cell differentiation and its impact on HIV disease states is poorly understood. In this study, we demonstrate that B‐lymphocyte‐induced maturation protein‐1 (Blimp‐1/Prdm1) is highly expressed in CD4+ T cells from chronically HIV‐infected (CHI) patients compared to cells from long‐term nonprogressors or healthy controls. Stimulation through the T‐cell receptor in the presence ofIL‐2 induces Blimp‐1 protein expression. We show here that Blimp‐1 levels are translationally regulated by microRNA‐9 (miR‐9). Overexpression of miR‐9 induces Blimp‐1 repression, restoring IL‐2 secretion in CD4+ T cells via reduction in the binding of Blimp‐1 to the il‐2 promoter. In CHI patients where IL‐2 expression is reduced and there is generalized T‐cell dysfunction, we show differential expression of both miR‐9 and Blimp‐1 in CD4+ cells compared with levels in long‐term nonprogressors. These data identify a novel miR‐9/Blimp‐1/IL‐2 axis that is dysregulated in progressive HIV infection. 相似文献
58.
Barnett Alana Edwards Katie Harper Rebecca Evans Elizabeth Alexander Derina Choudhary Mohini Richards Gareth 《Journal of autism and developmental disorders》2021,51(6):1866-1879
Journal of Autism and Developmental Disorders - Previous studies have reported positive correlations between autistic traits and disordered eating, though it is unclear whether the association is... 相似文献
59.
Turjeman Adi Babich Tanya Pujol Miquel Carratalà Jordi Shaw Evelyn Gomila-Grange Aina Vuong Cuong Addy Ibironke Wiegand Irith Grier Sally MacGowan Alasdair Vank Christiane Cuperus Nienke van den Heuvel Leo Leibovici Leonard Eliakim-Raz Noa 《European journal of clinical microbiology & infectious diseases》2021,40(9):2005-2010
European Journal of Clinical Microbiology & Infectious Diseases - Complicated urinary tract infection (cUTI) is a frequent cause of morbidity. In this multinational retrospective cohort study,... 相似文献
60.