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71.
The architecture of the colour centre in the human visual brain: new results and a review 总被引:21,自引:0,他引:21
We have used the technique of functional magnetic resonance imaging (fMRI) and a variety of colour paradigms to activate the human brain regions selective for colour. We show here that the region defined previously [Lueck et al. (1989) Nature, 340, 386-389; Zeki et al. (1991) J. Neurosci., 11, 641-649; McKeefry & Zeki (1997) Brain, 120, 2229-2242] as the human colour centre consists of two subdivisions, a posterior one, which we call V4 and an anterior one, which we refer to as V4alpha, the two together being part of the V4-complex. The posterior area is retinotopically organized while the anterior is not. We discuss our new findings in the context of previous studies of the cortical colour processing system in humans and monkeys. Our new insight into the organization of the colour centre in the human brain may also account for the variability in both severity and degree of recovery from lesions producing cerebral colour blindness (achromatopsia). 相似文献
72.
Aydin F Güngör F Cengiz AK Tuncer M Mahsereci E Ozdem S Cenkçi M Karayalçin B 《Nuclear medicine communications》2008,29(2):157-165
OBJECTIVE: To compare measured glomerular filtration rate (GFR) by single plasma sample methods (SPSMs), gamma camera Gates, 24-h endogenous creatinine clearance, and prediction equations (Cockcroft-Gault and modification of renal disease (MDRD)) with the two plasma sample method (TPSM) considered as the reference in potential kidney donors with normal renal function. METHODS: One hundred and fifteen subjects (50 male, 65 female; mean age 41.9+/-12.2 years) with normal renal function were prospectively included in this study. GFR was calculated by TPSM (120-min and 240-min samples) and SPSM (180-min sample). RESULTS: While there was strong statistically significant correlation between the TPSM and all SPSMs, low correlation was found in Gates, creatinine clearance, Cockcroft-Gault and MDRD. In all SPSMs, 95% limits of agreements were consistent with each other and within clinically acceptable limits. The lowest bias, median absolute difference, mean percentage error, and the best precision were found for Christensen and Groth's method as modified by Watson (CGmW). CONCLUSIONS: Among the SPSMs, CGmW can reflect GFR more accurately than the other methods. Neither the gamma camera Gates method nor the creatinine clearance method nor the prediction equations (Cockcroft-Gault and MDRD) could calculate GFR accurately. All these techniques could result in mistakes in the management of potential kidney donors. 相似文献
73.
Erturhan S Seçkiner I Zincirkeser S Erbagci A Celik M Yagci F Karakok M 《Annals of nuclear medicine》2008,22(3):225-229
Primary renal synovial sarcoma is a rarely seen renal neoplasm. An experienced uropathologist is needed to make the pathological diagnosis. A patient, operated on with a prediagnosis of renal cell carcinoma, the pathology of which was reported as synovial sarcoma, is presented in this article. 18F-fluoro-deoxyglucose positron emission tomography and computed tomography were performed preoperatively and in the postoperative follow-up to detect the primary tumor and lymph node metastases. 相似文献
74.
Percutaneous placement of biliary metallic stents in patients with malignant hilar obstruction: unilobar versus bilobar drainage 总被引:17,自引:0,他引:17
Inal M Akgül E Aksungur E Seydaoğlu G 《Journal of vascular and interventional radiology : JVIR》2003,14(11):1409-1416
PURPOSE: To evaluate the necessity of draining more than one hepatic duct in malignant hilar obstructions. MATERIALS AND METHODS: Two hundred seventeen self-expandable uncovered metallic stents (144 biliary Wallstents and 73 Memotherm nitinol stents) were placed percutaneously in 138 patients with unresectable malignant hilar obstructions. The patients included 76 men and 62 women, with a median age of 76 years (range, 43-82 years). Single-duct drainage was achieved in 74 patients (54%) by placing one stent (n = 59) or by placing an additional stent inserted telescopically through the first one (n = 15) to achieve an adequate stent length for long strictures (group 1). In 64 patients (46%), to maintain two-duct drainage, two stents were inserted through dual transhepatic tracts in a "Y" configuration (n = 41; group 2Y) or a single transhepatic tract in a "T" configuration (n = 23; group 2T). RESULTS: The overall technical success rate was 100%, and early clinical response was obtained in 89% of patients. The overall rate of major complications was 5.7% and did not show a statistically significant difference among groups 1, 2Y, and 2T in Bismuth type II, III, and IV obstructions. The patency rate was not statistically significant among groups 1, 2Y, and 2T in Bismuth type II and III obstructions (P >.05). However, in Bismuth type IV obstructions, the patency rate was significantly higher in group 2Y (P =.03; Kruskal-Wallis test). CONCLUSION: There is no need to place more than one stent in Bismuth type I, II, and III hilar obstructions. In Bismuth type IV obstructions, deployment of two parallel stents through dual transhepatic tracts should be performed. 相似文献
75.
76.
Nilüfer Aylin Acet
ztürk Asli G. Dilektasli
zge AydnGülü Ezgi Demirden Funda Cokun Ahmet Ursava Mehmet Karada Esra Uzaslan 《The clinical respiratory journal》2022,16(1):49
IntroductionEosinophilic airway inflammation is a recognized inflammatory pattern in subgroups of patients with chronic obstructive pulmonary disease (COPD). However, there are still conflicting results between various studies concerning the effect of eosinophils in COPD patients. Our aim with this study was to evaluate eosinophilic inflammation and its relation to the clinical characteristics in a group of COPD patients.MethodsStable COPD patients with FEV1% predicted < 50 or with ≥ 1 exacerbation leading to hospital admission or ≥2 moderate or severe exacerbation history were consecutively enrolled from outpatient clinics.ResultsWe included 90 male COPD patients, with a mean age of 63.3 ± 9.2. Mean FEV1% predicted was 35.9 ± 11.3. Eosinophilic inflammation (eosinophil percentage ≥2%) was evident in 54 (60%) of the patients. Participants with eosinophilic inflammation were significantly older and had better FEV1 predicted % values. Eosinophilic COPD patients were characterized with better quality of life and fewer symptoms. COPD patients with noneosinophilic inflammation used supplemental long‐term oxygen therapy (LTOT) more frequently compared to patients with eosinophilic inflammation (36.1% vs. 14.8%, p = 0.01). Eosinophilic inflammation is associated with less dyspnea severity measured by mMRC (OR: 0.542 95% CI: 0.342–0.859, p = 0.009) and less LTOT use (OR: 0.334 95% CI: 0.115–0.968, p = 0.04) regardless of age, severity of airflow limitation, and having frequent exacerbation phenotype.ConclusionOur study supports the growing evidence for a potential role of eosinophilic inflammation phenotype in COPD with distinctive clinical characteristics. Eosinophilic inflammation is inversely associated with dyspnea severity measured by mMRC and LTOT use independently from age, total number of exacerbations, St. George Respiratory Questionnaire (SGRQ) total score and FEV1% predicted. 相似文献
77.
目的 探讨血清胱抑素(Cyst-C)、尿微量白蛋白/肌酐(UmAlb/UCr)对高血压患者早期肾损害的诊断价值.方法 根据肾动态显像结果将85例原发性高血压患者分为早期肾功能损害组(A组)32例和单纯高血压组(B组)53例,并选取健康体检者50例为对照组,采用酶联免疫法测定各组Cyst-C、UmAlb/UCr、血清尿素氮(BUN)、血清肌酐(Scr)含量.结果 与对照组相比,A组及B组Cyst-C、UmAlb/UCr水平显著升高,B组则高于A组,差异有统计学意义(P<0.05),而三组BUN、Scr水平比较差异无统计学意义(P>0.05).随着高血压分级的增加,Cyst-C、UmAlb/UCr水平显著上升,其中Ⅲ级组患者显著高于Ⅰ级组及Ⅱ级组,差异有统计学意义(P.<0.05).Cyst-C灵敏性、特异性、准确性分别为81.6%、82.3%、69.2%,UmAlb/UCr灵敏性、特异性、准确性分别为84.5%、83.4%、76.9%,而UmAlb/UCr+Cyst-C灵敏性、特异性、准确性分别为93.2%、91.3%、92.3%.B组Cyst-C与UmAlb/UC联合检测阳性率显著高于单纯UmAlb/UCr或Cyst-C检测,差异有统计学意义(P<0.05).结论 Cyst-C与UmAlb/UC联合检测有助于高血压患者早期肾损害的诊断. 相似文献
78.
79.
Sait Demirkol M.D. Ugur Kucuk M.D. Oben Baysan M.D. Sevket Balta M.D. Turgay Celik M.D. Ibrahim Halil Kurt M.D. Hilal Olgun Kucuk M.D. Uygar Cagdas Yuksel M.D. Murat Unlu M.D. Mehmet Yokusoglu M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(9):1064-1070
Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle. 相似文献
80.