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51.
Yılmaz Yıldırır M. Faruk Us Naki Çolak Hamdi Özkan Serkan Yavuz Ali Disli Sahlan Ozturk Lemi Turker 《Medicinal chemistry research》2009,18(2):91-97
The sulfonamide functional group has aroused interest in both medicinal and bioorganic chemistry. In this study, some new phenylselanyl–1–(toluene-4-sulfonyl)-1H-tetrazole derivatives (2a–f) have been synthesized using dicyclohexylcarbodiimide/dimethylaminopyridine (DCC/DMAP). The structures of the presently synthesized compounds were elucidated by spectroscopic methods [Fourier-transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (NMR), 13C nuclear magnetic resonance-attached proton test (13C NMR-APT), and mass spectrometry (MS)]. In addition, the antimicrobial activity of the synthesized compounds and two antibiotics [sulfamethoxazole (SMX) and sulfamerazine (SRZ)] were investigated against some microorganisms. 相似文献
52.
Beta-thalassemia minor is a common, hereditary, and mostly symptomless disease. Previous studies have shown that lower hemoglobin values are associated with poorer cognitive functions. We aimed to evaluate the cognitive function in patients with beta-thalassemia minor. Thirty-two male subjects with beta-thalassemia minor and 32 sex-, age-, and education status-matched healthy subjects were enrolled in the study. Blood tests and P300 potentials were carried out. P300 potential latency in all patients was significantly longer than those in the control group (337.63+/-34.89 msec and 310.66+/-14.30 msec, respectively; t 4.046, P<0.001). The amplitudes of P300 in patient group were significantly lower than those in the control group (5.19+/-3.59 microV and 9.81+/-3.33 microV, respectively; t 5.349, P<0.001). In this study, we have found that P300 potentials are adversely affected for cognitive functions in patients with beta-thalassemia minor. 相似文献
53.
Sahiner B Chan HP Roubidoux MA Hadjiiski LM Helvie MA Paramagul C Bailey J Nees AV Blane C 《Radiology》2007,242(3):716-724
PURPOSE: To retrospectively investigate the effect of using a custom-designed computer classifier on radiologists' sensitivity and specificity for discriminating malignant masses from benign masses on three-dimensional (3D) volumetric ultrasonographic (US) images, with histologic analysis serving as the reference standard. MATERIALS AND METHODS: Informed consent and institutional review board approval were obtained. Our data set contained 3D US volumetric images obtained in 101 women (average age, 51 years; age range, 25-86 years) with 101 biopsy-proved breast masses (45 benign, 56 malignant). A computer algorithm was designed to automatically delineate mass boundaries and extract features on the basis of segmented mass shapes and margins. A computer classifier was used to merge features into a malignancy score. Five experienced radiologists participated as readers. Each radiologist read cases first without computer-aided diagnosis (CAD) and immediately thereafter with CAD. Observers' malignancy rating data were analyzed with the receiver operating characteristic (ROC) curve. RESULTS: Without CAD, the five radiologists had an average area under the ROC curve (A(z)) of 0.83 (range, 0.81-0.87). With CAD, the average A(z) increased significantly (P = .006) to 0.90 (range, 0.86-0.93). When a 2% likelihood of malignancy was used as the threshold for biopsy recommendation, the average sensitivity of radiologists increased from 96% to 98% with CAD, while the average specificity for this data set decreased from 22% to 19%. If a biopsy recommendation threshold could be chosen such that sensitivity would be maintained at 96%, specificity would increase to 45% with CAD. CONCLUSION: Use of a computer algorithm may improve radiologists' accuracy in distinguishing malignant from benign breast masses on 3D US volumetric images. 相似文献
54.
Hazirolan T Turkbey B Karcaaltincaba M Akata D Sahiner L Aytemir K Oto MA Arslan U Balkanci F Besim A 《Journal of computer assisted tomography》2007,31(1):5-8
OBJECTIVE: To assess impact of scanning direction on heart rates at certain levels of heart in electrocardiogram-gated 16-multidetector computed tomography (MDCT) detection of coronary artery bypass grafts and native coronary arteries. METHODS: Ninety patients with 219 grafts were studied by 16-MDCT. Forty-five patients were scanned craniocaudally. The remaining 45 patients were scanned caudocranially. Heart rates at each level were noted and compared between the 2 groups. RESULTS: The difference between mean heart rates of craniocaudal and caudocranial groups was found to be statistically significant at midcardiac, internal mammary artery origin, and cardiac base levels (P < 0.05). For the remaining levels, there was no statistically significant difference in mean heart rates. CONCLUSIONS: Performing electrocardiogram-gated 16-MDCT angiography for the evaluation of coronary arteries and bypass grafts in caudocranial direction provides lower heart rate at midcardiac and cardiac base levels of the heart, which are more prone to motion artifacts. 相似文献
55.
Turker H Sarica M Bilgici A Cengiz N Onar MK Us O 《Neurosciences (Riyadh, Saudi Arabia)》2008,13(1):79-83
Axillary neuropathy due to entrapment of the nerve in the quadrilateral space is seen rarely. Here, we describe a 24-year-old patient diagnosed with isolated axillary neuropathy that mimicked quadrilateral space syndrome. Quadrilateral or quadrangular space syndrome (QSS), first described by Cahill and Palmer in 1983, was defined as the entrapment of the distal branch of the axillary nerve and the posterior humeral circumflex artery (PHCA) in the quadrangular shaped anatomic space. We tracked the follow up of the patient for one year both clinically and electrophysiologically. Our aim in reporting this case is to stress the point that cases of such a nature usually represent situations of diagnostic and treatment challenges, where multidisciplinary approaches are required. 相似文献
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Analysis of interval change is important for mammographic interpretation. The aim of this study is to evaluate the use of an automated registration technique for computer-aided interval change analysis in mammography. Previously we developed a regional registration technique for identifying masses on temporal pairs of mammograms. In the current study, we improved lesion registration by including a local alignment step. Initially, the lesion position on the prior mammogram was estimated based on the breast geometry. An initial fan-shaped search region was then defined on the prior mammogram. In the second stage, the location of the fan-shaped region on the prior mammogram was refined by warping, based on an affine transformation and simplex optimization in a local region. In the third stage, a search for the best match between the lesion template from the current mammogram and a structure on the prior mammogram was carried out within the search region. This technique was evaluated on 124 temporal pairs of mammograms containing biopsyproven masses. Eighty-seven percent of the estimated lesion locations resulted in an area overlap of at least 50% with the true lesion locations and an average distance of 2.4 +/- 2.1 mm between their centroids. The average distance between the estimated and the true centroid of the lesions on the prior mammogram over all 124 temporal pairs was 4.2 +/- 5.7 mm. The registration accuracy was improved in comparison with our previous study that used a data set of 74 temporal pairs of mammograms. This improvement in accuracy resulted from the improved geometry estimation and the local affine transformation. 相似文献
58.
Ayse Oytun Bayrak MD Ilkay Koray Bayrak MD Hande Turker MD Muzaffer Elmali MD Mehmet Selim Nural MD 《Muscle & nerve》2010,41(5):661-666
The aim of this study was to determine the diagnostic value of ultrasonographic measurements in ulnar neuropathy at the elbow (UNE) and to assess the relationship between the measurements and the electrophysiological severity. The largest anteroposterior diameter (LAPD) and cross‐sectional area (CSA) measurements of the ulnar nerve were noted at multiple levels along the arm, and the distal‐to‐proximal ratios were calculated. Almost all of the measurements and swelling ratios between patients and controls showed statistically significant differences. The largest CSA, distal/largest CSA ratio, CSA at the epicondyle, and proximal LAPD had larger areas under the curve than other measurements. The sensitivity and specificity in diagnosing UNE were 95% and 71% for the largest CSA, 83% and 85% for the distal/largest CSA ratio, 83% and 81% for the CSA at the epicondyle, and 93% and 43% for the proximal LAPD, respectively. There was a statistically significant correlation between the electrophysiological severity scale score (ESSS) and the largest CSA, the CSA at the epicondyle and 2 cm proximal to the epicondyle, and the LAPD at the level of the epicondyle (P < 0.05). None of the swelling ratios showed a significant correlation with the ESSS. The largest CSA measurement is the most valuable ultrasonographic measurement both for diagnosis and determining the severity of UNE. Muscle Nerve, 2010 相似文献
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