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Purpose of the study: the aim of this study was to synthesize PFC fNIRS outcomes on the effects of cognitive tasks compared to resting/baseline tasks in healthy adults from studies utilizing a pre/post design.

Material and methods: original research studies were searched from seven databases (MEDLINE, EMBASE, CENTRAL, CINAHL, SCOPUS, PEDro and PubMed). Subsequently, two independent reviewers screened the titles and abstracts followed by full-text reviews to assess the studies' eligibility.

Results: eleven studies met the inclusion criteria and had data abstracted and quality assessed. Methodology varied considerably and yet cognitive tasks resulted in the ΔO2Hb increasing in 8 of the 11 and ΔHHb decreasing in 8 of 8 studies that reported this outcome. The cognitive tasks from 10 of the 11 studies were classified as “Working Memory” and “Verbal Fluency Tasks”.

Conclusions: although, the data comparison was challenging provided the heterogeneity in methodology, the results across studies were similar.  相似文献   

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In chronic myeloid leukaemia, CD34(+) stem/progenitor cells appear resistant to imatinib mesylate (IM) in vitro and in vivo. To investigate the underlying mechanism(s) of IM resistance, it is essential to quantify Bcr-Abl kinase status at the stem cell level. We developed a flow cytometry method to measure CrkL phosphorylation (P-CrkL) in samples with <10(4) cells. The method was first validated in wild-type (K562) and mutant (BAF3) BCR-ABL(+) as well as BCR-ABL(-) (HL60) cell lines. In response to increasing IM concentration, there was a linear reduction in P-CrkL, which was Bcr-Abl specific and correlated with known resistance. The results were comparable to those from Western blotting. The method also proved to be reproducible with small samples of normal and Ph(+) CD34(+) cells and was able to discriminate between Ph(-), sensitive and resistant Ph(+) cells. This assay should now enable investigators to unravel the mechanism(s) of IM resistance in stem cells.  相似文献   
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OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation.  相似文献   
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OBJECTIVES: To compare the effect of conjugated equine estrogens (CEE) and raloxifene on lipid profile and hemostasis. MATERIALS AND METHODS: A double-blind, randomized and parallel study was performed with 90 healthy postmenopausal women, aged 54 +/- 5 years, divided into three groups and submitted to daily therapy with either CEE 0.625 mg, raloxifene 60 mg or placebo for 4 months. The lipid profile, coagulation and fibrinolytic factors were analyzed. RESULTS: CEE increased the levels of high density lipoprotein cholesterol (HDL-C) from 49.0 to 56.8 mg/dl (p < 0.001), very low density lipoprotein cholesterol (VLDL-C) from 17.2 to 22.3 mg/dl (p < 0.001), and triglycerides from 86.0 to 111.7 mg/dl (p < 0.001), and decreased the levels of low density lipoprotein cholesterol (LDL-C) from 121.0 to 106.5 mg/dl (p < 0.001). The only significant effect of raloxifene was an increase in the levels of HDL-C from 46.0 to 47.8 mg/dl (p = 0.019). There was no significant reduction in LDL-C, from 115.5 to 110.2 mg/dl (p = 0.06), VLDL-C, from 21.7 to 20.0 mg/dl (p = 0.201), and triglycerides, from 108 to 100 mg/dl (p = 0.201). CEE decreased the levels of fibrinogen, from 370.5 to 326.8 g/l (p = 0.039) and the levels of antithrombin III, from 99.5 to 93.2% (p < 0.001). Raloxifene decreased the levels of fibrinogen, from 354.7 to 302.0 g/l (p = 0.009) and the levels of antithrombin III, from 102.4 to 98.5% (p = 0.039). CEE increased levels of protein C from 103.7 to 115.3 mg/l (p < 0.001) and raloxifene did not change the levels of protein C (107.9 to 105.1 mg/l; p = 0.158). CEE decreased the antigen levels of tissue plasminogen activator (t-PA) from 8.8 to 6.8 U/ml (p < 0.001), and of plasminogen activator inhibitor (PAI-1) from 30.8 to 21.6 U/ml (p < 0.010), whereas raloxifene had no significant effect on either t-PA, from 9.6 to 9.2 U/ml (p = 0.235) or PAI-1 antigen levels, from 32.1 to 30.4 U/ml (p = 0.538). CONCLUSION Both CEE and raloxifene exert significant effects on the lipid and coagulation profile. CEE had a more significant effect on fibrinolysis than raloxifene. These effects may have a significant impact on the cardiovascular risk that needs to be confirmed in larger studies.  相似文献   
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