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951.
952.
Nan-Han Lu MD Sandy Cheng-Yu Chen MD Jung-Mao Chou MD Tai-Hung Kuo MD Ching-Hui Yeh MD 《Journal of neuroimaging》2009,19(1):92-96
Germinomas in the central nervous system (CNS) are uncommon tumors and occur usually in the pineal or suprasellar regions. Primary spinal germinoma is extremely rare. Here we reported a rare case of an extramedullary germinoma in a young adult who presented with progressive paraparesis and retention of stool and urine. The MR image features with their differential diagnoses were discussed along with literature review of all previously reported 22 cases. 相似文献
953.
BACKGROUND AND OBJECTIVE: Bacterial infection is one of the major causes of acute exacerbation of COPD (AECOPD). This study was undertaken to investigate the microbiology of AECOPD. METHODS: Medical records from 494 episodes of AECOPD in patients admitted to the National Taiwan University Hospital from January 2000 to June 2004 were reviewed. Severity of COPD was classified according to the 2003 Global Initiative for Chronic Obstructive Lung Disease guideline. RESULTS: Potential pathogenic microorganisms were isolated from patients in 328 (66.4%) episodes of AECOPD. The predominant bacteria were Klebsiella pneumoniae (19.6%), Pseudomonas aeruginosa (16.8%) and Haemophilus influenzae (7.5%), followed by Acinetobacter baumannii (6.9%), Enterobacter species (6.1%) and Staphylococcus aureus (6.1%). The incidence of Streptococcus pneumoniae was 2.4%. Spirometry results obtained within 1 year of the exacerbation were available in 186 cases. K. pneumoniae was more frequently isolated in stage I COPD (39.1%) than stage II (16.6%), III (13.8%) and IV (9.4%). No glucose non-fermentative Gram-negative bacilli were isolated in stage I patients. Multivariate logistic regression analysis revealed that P. aeruginosa (odds ratio (OR) 3.19; 95% confidence interval (CI): 1.21-8.38), intubation (OR 14.81; 95% CI: 5.08-43.12) and age (OR 1.1; 95% CI: 1.03-1.17) were independent risk factors for mortality. CONCLUSIONS: Klebsiella pneumoniae and P. aeruginosa are the most common sputum pathogens in hospitalized patients with AECOPD in Taiwan, with the former being more commonly isolated from mild COPD and the latter associated with poor clinical outcome. These results should be considered when deciding which antibiotics should initially be used to treat patients with AECOPD. 相似文献
954.
Most tumor invasion into the heart is nonspecific and clinically silent. Myocardium metastasis rarely mimics a myocardial infarction. In this case, a cardiac metastasis from a squamous cell carcinoma presented with both persistent ST elevation and paroxysmal supraventricular tachycardia. The secondary lesion was located in the anterior wall and lateral wall of the left ventricle and induced electrocardiographic changes imitating an acute myocardial infarction. 相似文献
955.
The neural mechanisms of attentional orienting in visuospatial working memory for change detection were investigated. A spatial cue was provided with the onset time manipulated to allow more effective top-down control with an early cue than with a late cue. The change type was also manipulated so that accurate detection depended on color or the binding of color and location. The results showed that both the frontal and parietal regions subserved the change detection task without cueing. When data were collapsed over the two change types, early cueing increased activation in the right inferior frontal gyrus (IFG) and middle frontal gyrus (MFG) while late cueing increased activation in the right inferior parietal lobule (IPL) and temporoparietal junction (TPJ) as compared with the no-cue condition. The cue onset time led to different levels of enhancement in the frontal and posterior cortices related to top-down control and stimulus-driven orienting. For feature detection, early cueing increased activation in the right MFG and late cueing increased activation in the bilateral precuneus (PCu), right TPJ, and right cuneus. The neural correlates of conjunction detection involved the right PCu and cerebellum without cueing, were associated with the anterior MFG, left IFG, and the left STG with early cueing, and involved the right MFG, left IFG, and right IPL with late cueing. The left IFG was correlated with memory retrieval of the cued representation for conjunction detection, and the right posterior PCu was associated with maintenance and memory retrieval among competing stimuli. 相似文献
956.
短发夹RNA对前列腺癌细胞中PIM-1基因沉默效应的研究 总被引:1,自引:1,他引:0
目的:探讨脂质体介导的短发夹RNA(shRNA)对前列腺癌细胞中PIM-1基因表达的影响.方法:构建3种针对PIM-1 mRNA不同靶点的shRNA重组质粒表达载体,并转染前列腺癌PC-3细胞.分别采用逆转录-聚合酶链反应(RT-PCR)及蛋白印迹法(Westernblot)检测转染后细胞中PIM-1 mRNA及蛋白的表达情况.结果:转染48 h后,3种PIM-1基因靶向性shRNA表达质粒均可抑制PC-3细胞中PIM-1 mRNA和蛋白的表达,其中靶向PIM-1 mRNA第707-725位和1080-1098位序列的重组质粒干扰效果更显著.结论:本研究所构建的PIM-1 shRNA表达质粒可在体外高效特异地抑制前列腺癌细胞中PIM-1的表达,为下一步研究奠定了基础. 相似文献
957.
958.
959.
Diagnosis of peripheral lung cancer with three echoic features via endobronchial ultrasound 总被引:11,自引:0,他引:11
BACKGROUND: Endobronchial ultrasonography (EBUS) is useful in localizing peripheral lung lesions. Previous reports have revealed that several characteristic echoic patterns correlate well with the histopathologic findings of benign and malignant lesions. Therefore, EBUS may be also useful in the differential diagnosis of malignant lesions of the lung. OBJECTIVE: To assess the feasibility of EBUS in the differential diagnosis between malignant and benign lesions by the following three characteristic echoic features indicating malignancy: continuous margin; absence of a linear-discrete air bronchogram; and heterogeneous echogenicity. METHOD: EBUS images from 224 patients who undergone bronchoscopy for a peripheral lung lesion were analyzed. The sensitivity and specificity for each echoic feature or in combination in diagnosing malignancy or benignity were determined. RESULT: Continuous margin, absence of linear-discrete air bronchogram, and heterogeneous echogenicity are three echoic features indicating malignancy. The absence of linear-discrete air bronchogram has the highest sensitivity in the diagnosis of malignancy (91.9%), but the lowest specificity (62.4%). By contrast, a well-defined margin has the highest specificity (93.1%), but the lowest sensitivity (27.6%). The sensitivity and specificity for heterogeneous echogenicity are intermediate (65.0% and 90.1%, respectively). The negative predictive value for the malignancy of a lesion with none of these three echoic features is 93.7%. The positive predictive value for malignancy of a lesion with any two of the three echoic features is 89.2%. CONCLUSION: These results indicate that EBUS is useful as an adjunct in lung cancer diagnosis, especially when peripheral lung lesions are not visible in traditional bronchoscopy. 相似文献
960.
Chuah SK Changchien CS Wu KL Hu TH Kuo CM Chiu YC Chiu KW Kuo CH Chiou SS Lee CM 《Journal of gastroenterology and hepatology》2007,22(11):1737-1740
BACKGROUND AND AIM: There are limited reports on esophageal motility pressures in aged patients with achalasia and these are inconclusive. The aim of the present retrospective study was to understand the changes of esophageal motility in aged achalasia patients among the Taiwan population. METHODS: Manometric studies of 49 patients with achalasia had been performed through January 1998 to June 2005. The findings of lower esophageal sphincter (LES) basal and residual pressures and esophageal body contraction amplitudes were calculated and compared between the older and younger patient groups at different age cut-offs. RESULTS: Higher basal LES pressure increased significantly from the cut-off age of 65 years (i.e. patients over 65 had significantly higher basal LES pressure than younger patients: 37.0 +/- 4.19 mmHg vs 30.0 +/- 1.32 mmHg, P = 0.045). With patients > or =70 years old, it was more obvious (46.0 +/- 3.7 mmHg vs 29.6 +/- 1.2 mmHg, P = 0.001). Beginning at the cut-off age of 55, the LES residual pressure was significantly higher in older patients than those who were younger (14.0 +/- 11.06 mmHg vs 11.1 +/- 0.6 mmHg, P = 0.017). LES residual pressure is more significant in the older groups. A linear correlation between age and residual LES pressures (r = 0.383) was found. No differences were found in esophageal contraction pressure. CONCLUSIONS: Older achalasia patients in Taiwan have higher basal LES pressures, with a linear correlation between age and residual LES pressures. Age has no influence on esophageal contraction pressure. 相似文献