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81.
Aiman A Ali 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(3):e55-e59
BACKGROUND: Because the clinicopathologic effects of takhzeen al-qat are similar to those induced by smoking, the aim of this paper was to study the oral effect of 3 bad oral habits: takhzeen al-qat and cigarette and water-pipe smoking. STUDY DESIGN: This study was done on 33 Yemeni chronic qat users grouped as heavy cigarette smokers (GI), nonsmokers (GII) and water-pipe smokers (GIII). In all cases (n = 33) 2 biopsies were taken (n = 66), one from the buccal mucosa at the chewing side and the other from a similar mucosa at the contralateral (nonexposed) side. Biopsies were prepared for routine H&E staining. RESULTS: Acanthosis appeared in 88% and 0%, abnormal rete ridges in 70% and 3%, hyperparakeratosis in 67% and 0%, and epithelial dysplasia in 30% and 0% of the chewing and nonchewing sides, respectively, in the 3 groups. Epithelial dysplasia appeared in 41% of GI and GIII (smokers) but in only 9% of GII (nonsmokers). CONCLUSIONS: Takhzeen al-qat causes distinct histopathologic changes in the oral mucosa at the side of chewing, such as acanthosis, abnormal rete ridges, and hyperparakeratosis. The association between takhzeen al-qat and cigarette or water-pipe smoking may increase the risk of epithelial dysplasia. 相似文献
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83.
Zhiqiang Li Arthur F Gmitro Ali Bilgin Maria I Altbach 《Magnetic resonance in medicine》2007,57(6):1047-1057
Three-point Dixon techniques achieve good lipid-water separation by estimating the phase due to field inhomogeneities. Recently it was demonstrated that the combination of an iterative algorithm (iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL)) with a fast spin-echo (FSE) three-point Dixon method yielded robust lipid-water decomposition. As an alternative to FSE, the gradient- and spin-echo (GRASE) technique has been developed for efficient data collection. In this work we present a method for lipid-water separation by combining IDEAL with the GRASE technique. An approach to correct for errors in the lipid-water decomposition caused by phase distortions due to the switching of the readout gradient polarities inherent to GRASE is presented. The IDEAL-GRASE technique is demonstrated in phantoms and in vivo for various applications, including pelvic, musculoskeletal, and (breath-hold) cardiac imaging. 相似文献
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Holmes tremor is an arrhythmic, 2- to 5-Hz resting, postural, and kinetic upper extremity movement disorder that occurs weeks to months after acute mesencephalic pathology. We present a patient who developed tremor in three body parts postbrainstem hemorrhage with subsequent hypertrophic olivary degeneration and discuss the relevant clinical evolution. Our case is unique because in addition to expected upper extremity and cervical dystonic head tremors, the patient also developed a severe lower extremity movement disorder, which we believe to be a form of Holmes tremor. Tremor involving the lower extremity in this setting has not been previously reported. 相似文献
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Magnetically-labeled sensitized splenocytes to identify glioma by MRI: a preliminary study. 总被引:1,自引:0,他引:1
Ali S Arbab Ali M Rad A S M Iskander Kourosh Jafari-Khouzani Stephen L Brown Jamie L Churchman Guangliang Ding Quan Jiang Joseph A Frank Hamid Soltanian-Zadeh Donald J Peck 《Magnetic resonance in medicine》2007,58(3):519-526
This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells. 相似文献
89.
Ali S. Ziaee Nadia Khatibzadeh Alireza Rahimnia Ahmad S. Mousavi Shaban Mehrvarz 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2005,15(4):270-274
The aim of this study is to identify the effect of time and pressure of tourniquet in blood pressure and pulse rate immediately after the releasing of tourniquet in the upper and lower extremity of the orthopedic surgeries. This retrospective study examined 206 consecutive patients. Comparisons of the systolic and diastolic pressure and heart rate were made before the induction of anesthesia and tourniquet inflation, and immediately after the deflation. In general, there was no significant difference in hemodynamic changes between the upper- and lower-limb with regard to the type of anesthesia. There was no significant correlation between systolic blood pressure and tourniquet pressure, while by increasing the tourniquet time significantly, the systolic blood pressure decreases immediately after the deflation. Interestingly, the considerable increase in age paralleled with a significant decrease in the systolic blood pressure. The effect of tourniquet time is more than the age. There was no significant correlation between the tourniquet pressure and tourniquet time with diastolic blood pressure. Simply the increase in age significantly paralleled with the mild decrease in diastolic blood pressure Orthopedic surgeons are recommended not to rely on the benefits of tourniquet to raise blood pressure due to hypotensive conditions after the deflation especially in the old. 相似文献
90.