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Neurological soft signs (NSS) are well documented in individuals with schizophrenia (SZ), yet so far, the relationship between NSS and specific symptom expression is unclear. We studied 76 SZ patients using magnetic resonance imaging (MRI) to determine associations between NSS, positive symptoms, gray matter volume (GMV), and neural activity at rest. SZ patients were hypothesis-driven stratified according to the presence or absence of auditory verbal hallucinations (AVH; n = 34 without vs 42 with AVH) according to the Brief Psychiatric Rating Scale. Structural MRI data were analyzed using voxel-based morphometry, whereas intrinsic neural activity was investigated using regional homogeneity (ReHo) measures. Using ANCOVA, AVH patients showed significantly higher NSS in motor and integrative functions (IF) compared with non-hallucinating (nAVH) patients. Partial correlation revealed that NSS IF were positively associated with AVH symptom severity in AVH patients. Such associations were not confirmed for delusions. In region-of-interest ANCOVAs comprising the left middle and superior temporal gyri, right paracentral lobule, and right inferior parietal lobule (IPL) structure and function, significant differences between AVH and nAVH subgroups were not detected. In a binary logistic regression model, IF scores and right IPL ReHo were significant predictors of AVH. These data suggest significant interrelationships between sensorimotor integration abilities, brain structure and function, and AVH symptom expression.  相似文献   
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目的研究小细胞肺癌(SCLC)和非小细胞肺癌(NSCLC)的分类问题。方法217例肺癌患者.其中男性165例.殳性52例;年龄35~80岁,平均年龄61.5岁。其中SCLC108例,NSCLC109例。提取患者764幅肺癌CT图像的灰度共生矩阵,选取对比度、熵、能量和逆差矩4个特征值,借助临床确诊结果,利用多层前向(BP)、径向基函数(RBF)人工神经网络对特征进行训练测试。结果BP人工神经网络对10%的78例样本进行测试,SCLC42例预测正确.NSCLC33例预测正确.3例预测失败。RBF神经网络对10%的78例测试样本进行测试,SCLC42例预测正确.NSCLC36例预测正确、类似方法对样本总数的70%进行训练,用30%的230例进行测试;BP人工神经网络有209例预测正确。正确率为90.9%:其中SCLC111例预测正确,正确检出率为88.8%;NSCLC98例预测正确,正确检出率为93.3%。RBF人工神经网络有216例预测正确.正确率为93.9%,其中SCLC117例预测正确,正确率为93.6%;NSCLC99例预测正确,止确检出率为94.3%。可见BP、RBF人1二神经网络对SCLC和NSCLC均具有90%以上的正确率,高于人工诊断结果。结论基于灰度共生矩阵的对比度、熵、能量和逆差矩4个特征值能反映SCLC和NSCLC的有效特征参量.通过人工神经网络能达到分类目的,辅助临床治疗。  相似文献   
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目的 探讨脑皮质梗死慢性期非流利性失语症患者灰质体积的改变及其与语言功能的关系。  相似文献   
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【摘要】〓目的〓探讨不同血清前列腺特异抗原(PSA)相关肿瘤标志物在前列腺癌中的临床价值。方法〓回顾我院2011年1月至2014年12月入院治疗的300例疑似前列腺癌患者的临床资料。上述患者入院后经直肠实施前列腺穿刺活检术后,将患者分为前列腺癌与非前列腺癌两组,其中前列腺癌88例,非前列腺癌212例(前列腺增生138例,前列腺炎78例)。对比两组患者的F-PSA/T-PSA、PSAD与(F-PSA/T-PSA)/PSAD水平,评估上述指标对于前列腺癌的诊断价值。结果〓两组患者检测F-PSA/T-PSA、PSAD与(F-PSA/T-PSA)/PSAD结果显示,组间差异具统计学意义(P<0.05)。不同PSA指标相同敏感度情况下,(F-PSA/T-PSA)/PSAD对于前列腺癌的诊断特异性最高,差异具统计学意义(P<0.05)。结论〓PSA相关肿瘤标志物检测中,(F-PSA/T-PSA)/PSAD的水平变化对前列腺癌早期诊断具较高特异性。  相似文献   
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《Urologic oncology》2015,33(5):202.e19-202.e28
ObjectiveTo evaluate the additive value of the prostate cancer gene 3 (PCA3) urine test to serum prostate-specific antigen (PSA) in prostate cancer (PC) screening among breast cancer, early-onset gene (BRCA) mutation carriers. This study was performed among the Dutch participants of IMPACT, a large international study on the effectiveness of PSA screening among BRCA mutation carriers.Materials and methodsUrinary PCA3 was measured in 191 BRCA1 mutation carriers, 75 BRCA2 mutation carriers, and 308 noncarriers. The physicians and participants were blinded for the results. Serum PSA level≥3.0 ng/ml was used to indicate prostate biopsies. PCA3 was evaluated (1) as an independent indicator for prostate biopsies and (2) as an indicator for prostate biopsies among men with an elevated PSA level. PC detected up to the 2-year screening was used as gold standard as end-of-study biopsies were not performed.ResultsOverall, 23 PCs were diagnosed, 20 of which were in men who had an elevated PSA level in the initial screening round. (1) PCA3, successfully determined in 552 participants, was elevated in 188 (cutoff≥25; 34%) or 134 (cutoff≥35; 24%) participants, including 2 of the 3 PCs missed by PSA. PCA3 would have added 157 (≥25; 28%) or 109 (≥35; 20%) biopsy sessions to screening with PSA only. (2) Elevated PCA3 as a requirement for biopsies in addition to PSA would have saved 37 (cutoff≥25) or 43 (cutoff≥35) of the 68 biopsy sessions, and 7 or 11 PCs would have been missed, respectively, including multiple high-risk PCs. So far, PCA3 performed best among BRCA2 mutation carriers, but the numbers are still small. Because PCA3 was not used to indicate prostate biopsies, its true diagnostic value cannot be calculated.ConclusionsThe results do not provide evidence for PCA3 as a useful additional indicator of prostate biopsies in BRCA mutation carriers, as many participants had an elevated PCA3 in the absence of PC. This must be interpreted with caution because PCA3 was not used to indicate biopsies. Many participants diagnosed with PC had low PCA3, making it invalid as a restrictive marker for prostate biopsies in men with elevated PSA levels.  相似文献   
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