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71.
Serum erythropoietin level less than 100U/L and a transfusion requirement of less than 2 units per month are the best predictive factors for response to treatment by erythropoiesis-stimulating agents in low/int-1 myelodysplastic syndromes. To investigate the factors influencing the response to erythropoiesis-stimulating agents, we enrolled 127 low/int-1 myelodysplastic syndrome patients at diagnosis in a biological study of erythropoiesis. The 54 non-responders had a significantly lower number of burst-forming unit-erythroid and colony-forming unit-erythroid than responders. Erythropoietin-dependent proliferation and survival, and phospho (p)-ERK1/2 expression in steady state and after erythropoietin stimulation were defective in cultured erythroblasts. By flow cytometry, p-ERK1/2 was significantly lower in bone marrow CD45/CD71+/GPAcells from non-responders compared to responders or controls. Receiver Operator Characteristic curve analysis showed that this flow cytometry test was a sensitive biomarker for predicting the response to erythropoiesis-stimulating agents.  相似文献   
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OBJECTIVES: This study examined the relationship between maternal tobacco and alcohol consumption during the first trimester of pregnancy and oral clefts. METHODS: Data were derived from a European multicenter case-control study including 161 infants with oral clefts and 1134 control infants. RESULTS: Multivariate analyses showed an increased risk of cleft lip with or without cleft palate associated with smoking (odds ratio [OR] = 1.79, 95% confidence interval [CI] = 1.07, 3.04) and an increased risk of cleft palate associated with alcohol consumption (OR = 2.28, 95% CI = 1.02, 5.09). The former risk increased with the number of cigarettes smoked. CONCLUSIONS: This study provides further evidence of the possible role of prevalent environmental exposures such as tobacco and alcohol in the etiology of oral clefts.  相似文献   
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Female BRCA1/2 mutation carriers develop in up to 50% breast cancer (BC) before age 50 years. We investigated whether the specific histologic features of BRCA1/2-associated breast cancer influence imaging. We correlated the mammographic results with the histology of 34 BC in BRCA1/2 mutation carriers and 34 sporadic cancers in patients, matched for age and year of diagnosis. Mammography was significantly more frequently false-negative in carriers than controls (62% vs. 29% p = 0.01), despite comparable tumor size (mean solidus in circle 1.51 vs. 1.75) and breast density (high 41% vs. 53%). The image in carriers was significantly less as spiculated mass (6 vs. 18 p = 0.01). Cancers of BRCA1/2 mutation carriers had frequently higher mitotic counts (p < 0.0001) and prominent pushing margins around the tumor (p = 0.08) (p = 0.05 for 32 BRCA1). We also observed that prominent "pushing margins" correlated significantly with a false-negative mammography (p = 0.005) and with a mammographic image of a smooth, not a spiculated, mass (p = 0.01). False-negative mammography correlated independently with: BRCA1/2 mutation (p = 0.02), prominent pushing margins (p = 0.03) and high breast density (p = 0.01). MRI was carried out in 12 carriers, had 100% sensitivity and detected 5 cancers, still occult at physical examination and mammography. A BRCA1/2 mutation and high breast density at mammography contribute independently to false-negative mammography results. In mutation carriers any mammographic mass must be regarded with suspicion. Pushing margins of the tumor partly explain these results. For early BC detection in mutation carriers additional methods like MRI may be needed. This may not be necessary in other young women with breast symptoms.  相似文献   
76.
2型糖尿病的预测性遗传学检测可能引起不切实际的期望   总被引:1,自引:0,他引:1  
A  Cecile  JW  Janssens  Marta  Gwinn  Rodoffo  Valdez  KM  Venkat  Narayan  Muin  J  Khoury  谢超 《英国医学杂志》2006,9(6):331-332
今年年初,《纽约时报》头版头条报道了TCF7L2基因变异与2型糖尿病相关。主要研究者KariStefansson告诉《纽约时报》,这一发现可能会导致一种新的诊断性检测法产生,用于识别携带糖尿病变异基因的个体。他说,这将促使那些知道自己有糖尿病高风险的人们避免采取引起糖尿病的生活方式。一位苏格兰科学家领导着该研究小组,《格拉斯哥先驱报》曾率先报道他们的工作,“糖尿病致病基因的发现将有助于科学家治疗糖尿病”。  相似文献   
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78.
This study examined the effects of alcohol on the ability to execute and inhibit behavior in a context in which preliminary information signaled the likelihood that a response should be executed or suppressed. Adults (N = 24) performed a cued go/no-go task that required quick responses to go targets and suppression of responses to no-go targets. Cue dependency was manipulated by varying the predictive validity of the cues, and performance was tested under 3 doses of alcohol: 0.00 g/kg, 0.45 g/kg, and 0.65 g/kg. Dose-dependent increases in cue dependence were only observed with highly predictive cues. Results suggest that alcohol-induced increases in stimulus control over behavior might be most likely in situations when stimulus control over behavior has already been established.  相似文献   
79.
Potent liposomal PorA formulations containing various lipopolysaccharide (LPS) derivatives were developed. The following adjuvants were compared: the commonly used aluminum phosphate (AlPO(4)), and three LPS like adjuvants: monophosphoryl lipid A (MPL), lipopolysaccharide (galE LPS) and the less toxic LPS mutant lpxL1. The immunogenicity in mice was evaluated and compared with that against an outer membrane vesicle (OMV) vaccine. The IgG isotype distribution and bactericidal activity were determined. Furthermore, PorA specific proliferation of lymph node cells after immunization and restimulation in vitro was studied with selected formulations. Both AlPO(4) and MPL were unable to improve the functional immunogenicity (i.e. bactericidal response) of liposomal PorA. Besides, when these adjuvants were used, the percentage of responders in the groups did not reach 100%. This was also observed with non adjuvated PorA-liposomes or OMV. Of the adjuvants studied, only galE LPS and lpxL1 LPS were capable of increasing the immunogenicity and avoid non responsiveness against PorA-liposomes. Importantly, the adjuvant activity of lpxL1 LPS was accompanied by an improved PorA specific proliferation of lymph node cells and a concomitant increase in IL-2 production. In conclusion and considering its lower toxicity, lpxL1 LPS adjuvated liposomes are superior to other formulations tested.  相似文献   
80.
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