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991.
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993.
Zuyun Liu Guangzhen Zhong Shujuan Li Wan Deng Yuechan Zhang Degui Qian Li Jin Xiaofeng Wang 《Age (Dordrecht, Netherlands)》2015,37(4)
Both activities of daily living (ADL) and some blood biomarkers (such as albumin) have been associated with mortality in very elderly people, but scarce data is available on the predictive performance of them in isolation or in combination, which is important for clinicians in decision making. Here, based on prospective mortality data over a 6-year follow-up period from 433 long-lived individuals (LLIs) aged 95+ years in the Rugao longevity cohort, we aimed to evaluate Cox proportional hazard ratios (HRs) and discriminative power (ROC curve) of 14 biomarkers and ADL for all-cause mortality. We found that six biomarkers (total triglyceride, albumin, low-density lipoprotein cholesterol, platelet count, lymphocyte count, and neutrophil count) were associated with mortality with a p < .10 in the univariate model. Significant associations of albumin and neutrophil count with mortality were observed when they were simultaneously included in a multivariate model, with HRs of 0.97 (95 % CI 0.94, 0.99; p = .005) and 1.09 (95 % CI 1.00, 1.18; p = .043). With respect to ADL, the corresponding HR was 1.10 (95 % CI 1.07, 1.14; p < .001). Low albumin (<40 g/L) combined with ADL dependent had a significantly increased mortality risk (HR = 2.19; 95 % CI 1.63, 2.95). Albumin and ADL separately showed good discriminative accuracies (area under the curve [AUC] = 0.68 and 0.66, respectively), and their combination had an increased predictive utility (AUC = 0.73). In conclusion, both albumin and ADL are efficient predictors of all-cause mortality in long-lived populations and their combination further increases discriminative power. The preliminary findings, if validated and translated, would help clinicians to identify the elderly people at varying mortality risk. 相似文献
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995.
In vitro TNF blockade enhances ex vivo expansion of regulatory T cells in patients with immune thrombocytopenia 下载免费PDF全文
Tumour necrosis factor‐α (TNF) is an inflammatory cytokine that is elevated in a number of autoimmune diseases including immune thrombocytopenia (ITP), a bleeding disorder characterized by low platelet counts. In vitro TNF blockade increases expansion of the regulatory T cell (Treg) IKZF2 (also termed Helios) subset in T cell‐monocyte cocultures from healthy donors, but its role on proliferative responses of Tregs in ITP patients, who have altered immunoregulatory compartment, remains unclear. TNF in CD4+ T cells from patients with chronic ITP were elevated and negatively correlated with peripheral Treg frequencies, suggesting a possible inhibitory effect of TNF on ITP Tregs. In vitro antibody neutralization with anti‐TNF in T cell‐monocyte cocultures resulted in a robust expansion of pre‐existing ITP Tregs, higher than in healthy controls. Similar to the effects of anti‐TNF antibodies, TNF blockade with antibodies against TNFRSF1B (anti‐TNFRSF1B, previously termed anti‐TNFRII) almost doubled ITP Treg expansion whereas neutralization with anti‐TNFRSF1A (anti‐TNFRI) antibodies had no effect on proliferative responses of Tregs. In addition, TNFRSF1B levels on ITP Tregs were significantly elevated, which may explain the increased susceptibility of patient Tregs to the actions of TNF blockade. Altogether, these data raise the possibility that TNF blockers, through their ability to increase Treg proliferation, may be efficacious in ITP patients. 相似文献
996.
胶囊内镜与多排螺旋CT在诊断不明原因消化道出血中的临床价值 总被引:2,自引:0,他引:2
目的探讨胶囊内镜(capsule endoscopy,CE)与多排螺旋CT(mutiple-detector computertomography,MDCT)在不明原因消化道出血中的诊断价值。方法应用CE和MDCT对60例不明原因消化道出血患者进行比较研究,并与手术病理结果对照。结果CE的诊断阳性率为60.0%(36/60),MDCT的诊断阳性率为38.3%(23/60),P〈0.01。CE和MDCT联合诊断的阳性率为66.7%(40/60),与单纯CE相比P〉0.05,与单纯MDCT相比P〈0.01。诊断的主要病变有间质瘤、血管瘤、克罗恩病、血管畸形、Meckel憩室、钩虫病等。在手术确诊病例中,两者的诊断阳性率差异无统计学意义。结论对不明原因消化道出血,CE的诊断阳性率高于MDCT,联合检查并未提高诊断阳性率,但综合考虑CE和MDCT检查的优缺点,认为MDCT检查在小肠肿瘤的病变性质及肠外情况全面了解中具有优势,建议对不明原因消化道出血进行CE和MDCT的联合检查。 相似文献
997.
Yu Z Sánchez-Velar N Catrina IE Kittler EL Udofia EB Zapp ML 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(11):4027-4032
An important goal of contemporary HIV type 1 (HIV-1) research is to identify cellular cofactors required for viral replication. The HIV-1 Rev protein facilitates the cytoplasmic accumulation of the intron-containing viral gag-pol and env mRNAs and is required for viral replication. We have previously shown that a cellular protein, human Rev-interacting protein (hRIP), is an essential Rev cofactor that promotes the release of incompletely spliced HIV-1 RNAs from the perinuclear region. Here, we use complementary genetic approaches to ablate hRIP activity and analyze HIV-1 replication and viral RNA localization. We find that ablation of hRIP activity by a dominant-negative mutant or RNA interference inhibits virus production by mislocalizing Rev-directed RNAs to the nuclear periphery. We further show that depletion of endogenous hRIP by RNA interference results in the loss of viral replication in human cell lines and primary macrophages; virus production was restored to wild-type levels after reintroduction of hRIP protein. Taken together, our results indicate that hRIP is an essential cellular cofactor for Rev function and HIV-1 replication. Because hRIP is not required for cell viability, it may be an attractive target for the development of new antiviral strategies. 相似文献
998.
999.
Rice yields decline with higher night temperature from global warming 总被引:52,自引:0,他引:52
Peng S Huang J Sheehy JE Laza RC Visperas RM Zhong X Centeno GS Khush GS Cassman KG 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(27):9971-9975
The impact of projected global warming on crop yields has been evaluated by indirect methods using simulation models. Direct studies on the effects of observed climate change on crop growth and yield could provide more accurate information for assessing the impact of climate change on crop production. We analyzed weather data at the International Rice Research Institute Farm from 1979 to 2003 to examine temperature trends and the relationship between rice yield and temperature by using data from irrigated field experiments conducted at the International Rice Research Institute Farm from 1992 to 2003. Here we report that annual mean maximum and minimum temperatures have increased by 0.35 degrees C and 1.13 degrees C, respectively, for the period 1979-2003 and a close linkage between rice grain yield and mean minimum temperature during the dry cropping season (January to April). Grain yield declined by 10% for each 1 degrees C increase in growing-season minimum temperature in the dry season, whereas the effect of maximum temperature on crop yield was insignificant. This report provides a direct evidence of decreased rice yields from increased nighttime temperature associated with global warming. 相似文献
1000.
Gene expression profile of murine long-term reconstituting vs. short-term reconstituting hematopoietic stem cells 下载免费PDF全文