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排序方式: 共有2185条查询结果,搜索用时 31 毫秒
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32.
Manuel F. Casanova Ayman S. El-Baz Jay Giedd Judith M. Rumsey Andrew E. Switala 《Journal of autism and developmental disorders》2010,40(1):21-29
Recent studies provide credence to the minicolumnar origin of several developmental conditions, including dyslexia. Characteristics
of minicolumnopathies include abnormalities in how the cortex expands and folds. This study examines the depth of the gyral
white matter measured in an MRI series of 15 dyslexic adult men and eleven age-matched comparison subjects. Measurements were
based upon the 3D Euclidean distance map inside the segmented cerebral white matter surface. Mean gyral white matter depth
was 3.05 mm (SD ± 0.30 mm) in dyslexic subjects and 1.63 mm (SD ± 0.15 mm) in the controls. The results add credence to the
growing literature suggesting that the attained reading circuit in dyslexia is abnormal because it is inefficient. Otherwise
the anatomical substratum (i.e., corticocortical connectivity) underlying this inefficient circuit is normal. A deficit in
very short-range connectivity (e.g., angular gyrus, striate cortex), consistent with results of a larger gyral window, could
help explain reading difficulties in patients with dyslexia. The structural findings hereby reported are diametrically opposed
to those reported for autism. 相似文献
33.
Significance of matrix metalloproteinase 9 and CD34 expressions in esophageal carcinoma: correlation with DNA content 总被引:2,自引:0,他引:2
El-Kenawy Ael-M Lotfy M El-Kott A El-Shahat M 《Journal of clinical gastroenterology》2005,39(9):791-794
BACKGROUND: Esophageal carcinoma is common in many countries, and it is characterized by poor prognosis and rapid clinical progression with a high frequency of lymph node metastasis and recurrence. The present study was carried out to evaluate the correlation between vascular endothelial cell marker (CD34), matrix metalloproteinase type 9 (MMP9), and DNA content in esophageal carcinoma. METHODS: A total of 38 patients were classified with histopathologic examination as 8 cases with adenocarcinoma, 24 cases with squamous cell carcinoma, and the last 6 cases with undifferentiated carcinoma. The obtained results of the patient group were compared with the results of 6 cases with proven normal esophageal mucosa as a control group. The samples of patients and controls were subjected to immunohistochemical evaluation of CD34 and MMP9 expression along with DNA index determination using flow cytometry. RESULTS: There was a significant difference between patients and normal cases in DNA index, CD34, and MMP9 pattern (P = 0.003, <0.001, and 0.002, respectively). DNA index was positively correlated with MMP9 (r = 0.574, P < 0.001) and with CD34 (r = 0.562, P < 0.001). MMP9 was correlated with CD34 (r = 0.55, P < 0.001). A significant difference was found in both microvessel density and MMP9 expression with respect to tumor grade and stage. The microvessel density in patients with highly positive staining for MMP9 was higher than in those with negative and weak staining for MMP9 (P = 0.002). CONCLUSION: The analysis of DNA content along with detection of CD34 and MMP9 in esophageal cancer can successfully differentiate the different pathologic lesions and hence can be used powerfully in disease prognosis reflecting valuable information about the aggressiveness and activity of those lesions. 相似文献
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Mohamed A. Bedewi Ayman A. Elsifey Tariq Alfaifi Mamdouh A. Kotb Mohamed S. Abdelgawad Abdelmohsen Mohamed Bediwy Sherine Mohamed Swify Ezzat M. Awad 《Medicine》2021,100(3)
The purpose of this study is to investigate sonoelastographic features of the tibial nerve.The study included 72 tibial nerves in 36 healthy subjects. High resolution ultrasound and Shear wave elastography were used to evaluate the tibial nerve. Cross sectional area and stiffness were measured.The mean cross sectional area of the tibial nerve was 13.4 mm2. The mean shear elastic modulus of the tibial nerve in the short axis was 23.3 kPa. The mean shear elastic modulus of the tibial nerve in long axis was 26.1 kPa. The tibial nerve elastic modulus also showed no correlation with cross sectional area neither in the long axis nor short axis. Age, height, weight, and body mass index showed no correlation with tibial nerve elastic modulus in short or long axes.The elastic modulus of the tibial nerve has been determined in healthy subjects and can serve as a reference for future assessment of polyneuropathy. 相似文献
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Risks of red blood cell alloimmunization in transfusion‐dependent β‐thalassemia in Oman: a 25‐year experience of a university tertiary care reference center and a literature review 下载免费PDF全文
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Faris MoezAlIslam E. Vitiello Michael V. Abdelrahim Dana N. Cheikh Ismail Leila Jahrami Haitham A. Khaleel Sharfa Khan Maryam S. Shakir Ayman Z. Yusuf Ayesha M. Masaad Alyaa A. Bahammam Ahmed S. 《Sleep & breathing》2022,26(3):1365-1376
Sleep and Breathing - This study investigated the relationships between eating habits and sleep quality among university students. In a cross-sectional study, university students completed a... 相似文献
40.
Ayman Saeyeldin Mohammad A. Zafar Lauren A. Baldassarre Hamid Mojibian Bulat A. Ziganshin Sandip K. Mukherjee John A. Elefteriades 《The International journal of angiology》2021,30(2):160
Aortic diameter is a powerful predictor of adverse aortic events, such as aortic rupture or dissection, forming the basis of prophylactic surgical repair criteria. Limited evidence is available regarding the association of aortic wall thickness (AWT) with these adverse aortic events. We present the case and surgical video of a 73-year-old man with chest pain and an increased AWT, who underwent ascending aortic repair and deep hemiarch placement under deep hypothermic circulatory arrest. Surgical pathology demonstrated evidence of aortic delamination and medial separation, indicative of an impending dissection. The patient recovered uneventfully, and his chest pain ultimately resolved after open repair. In this patient, increased AWT was felt to be the precursor to a potential aortic catastrophe. 相似文献