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Purpose  

Since primary tumor cells from patients have been used as a model for assessment of drug response for individual patients, this study aims to evaluate the reliability of such a model in colorectal cancer (CRC) in predicting the response of tumor tissues through comparison of their expression profiles.  相似文献   
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Testosterone has been shown to affect motor behavior and nigrostriatal dopaminergic (NSDA) system in young and adult male rats. However, it is not known whether exogenous testosterone intervention to aged male rats can ameliorate age-related motor impairment. Thus, in the present study, the open field motor behavior and adhesive tape removal motor performance as well as the expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT) of NSDA system were examined in aged male rats following chronic subcutaneous injections of testosterone propionate (TP). Aged rats showed significantly reduced open field motor behavior and adhesive tape removal motor performance compared to adult rats. Chronic TP supplement significantly ameliorated the age-related motor deficits. The expression of TH and DAT of NSDA system was significantly enhanced in TP-treated aged rats revealed by RT-PCR, Western blot and immunohistochemistry analysis respectively. The results imply that chronic TP treatment may favorably improve the declined motor behavior and motor performance with aging. Testosterone propionate supplement that facilitated NSDA system may influence the maintenance of motor behavior and performance in aged rats.  相似文献   
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Objective: To assess the left ventricular (LV) longitudinal systolic function and asynchrony in patients with coronary atherosclerotic heart disease (CAD) by syngo velocity vector imaging (VVI). Methods: Twenty‐eight control subjects and 79 patients with CAD were examined, including 28 patients with myocardial infarction, 26 patients with coronary lumen stenosis <50%, and 25 patients with myocardial ischemia. According to the results of coronary arteriography and electrocardiogram (ECG), the myocardial segments of the LV of CAD patients were divided into four groups: ischemic, infarcted, nonischemic, and normal. Dynamic imaging was performed on all subjects. The systolic peak strain (Smax), systolic strain rate (SRmax), time to peak strain (PTs), and time to peak strain rate (PTsr) in every cardiac cycle were measured. Results: A total of 1,253 out of 1,712 (96.5%) segments were successfully analyzed with VVI. Smax and SRmax of the ischemic and infarcted segments were impaired in CAD patients. Optimal sensitivity and specificity were obtained with strain and strain rate cutoffs of ?14.08% and ?0.83 s?1, respectively, for detecting ischemic segments and ?6.65% and ?0.38 s?1, respectively, for detecting infarcted segments. The PTs and PTsr were significantly longer in the ischemic and infarcted segments compared to those of the control group. Conclusions: Utilizing VVI, the longitudinal strain, strain rate, and peak time in CAD patients are easy to obtain and reproducible. Strain and strain rate cutoff values of abnormal myocardium are valuable for detecting ischemia and infarction. The PTs and PTsr values possibly estimate myocardium asynchrony in CAD patients. (Echocardiography 2012;29:340‐345)  相似文献   
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