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排序方式: 共有479条查询结果,搜索用时 15 毫秒
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Jeremy Michals Schraw Yong Quan Dong Mehmet Fatih Okcu Michael E. Scheurer Michele R. Forman 《Cancer causes & control : CCC》2014,25(1):73-80
Milk formula feeding can elevate insulin-like growth factor-1 levels, possibly impacting leukemogenesis. The intent of the current study is to examine the associations between infant feeding practices and age at introduction of solids on risk of childhood acute lymphoblastic leukemia (ALL). Incident cases of infant and childhood (aged ≤14 years) ALL (n = 142) were enrolled in a case–control study. Cases were frequency matched on age, sex, race, and ethnicity to two sets of controls (n = 284 total). Multivariable logistic regression was used to determine the association between infant feeding practices and age at the introduction of solids and the odds ratio of ALL. In adjusted multivariable analyses, each additional month of formula feeding was associated with a 1.17 (1.09–1.25) odds ratio; each additional month of age at introduction of solids was associated with a 1.18 (1.07–1.30) odds ratio. In this study, longer duration of formula feeding and later age at the introduction of solid foods were independently associated with increased risk of ALL. Additional studies are needed to address the factors influencing duration of formula feeding and delayed introduction of solids. The results support the potential role of energy balance in early life as a contributor to risk for pediatric acute lymphoblastic leukemia. 相似文献
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Abaci A Oguzhan A Unal S Kiranatli B Eryol NK Basar E Ergin A Cetin S 《Cardiology》2002,98(1-2):50-59
OBJECTIVES: The vena contracta is the narrowest region of the regurgitant or stenotic jet just downstream the orifice and reflects the size of that orifice. This study was performed to assess the accuracy of the vena contracta width (VCW) in evaluating the severity of mitral stenosis (MS) and to compare the mitral valve area (MVA) determined by VCW with MVAs obtained by other more traditional echocardiographic methods. METHODS: We studied 59 patients (43 females, 42 +/- 14 years) with MS. VCW was measured in the apical four chamber view by Doppler color flow mapping. The largest diameter of the VCW during diastole was measured for at least three cardiac cycles and averaged. MVA was calculated from the following equation: pir(2), where r = VCW/2. MVA was also determined by planimetry, the pressure half-time method, and by the Gorlin formula. RESULTS: In this study, the width of the vena contracta ranged from 0.89 to 1.73 cm (mean 1.30 +/- 0.21). MVA, calculated based on the VCW, ranged from 0.63 to 2.35 cm(2) (mean 1.36 +/- 0.41). MVA by VCW (1.36 +/- 0.41 cm(2)) showed good correlations with three comparative techniques: (1) the cross-sectional area by planimetry (1.35 +/- 0.36 cm(2), mean difference = 0.21 +/- 0.16 cm(2), y = 0.91x + 0.14, r = 0.79, SEE = 0.26 cm(2), p < 0.001); (2) the area derived from the Doppler pressure half-time (1.27 +/- 0.32 cm(2), mean difference = 0.22 +/- 0.19 cm(2), y = 0.97x + 0.13, r = 0.76, SEE = 0.27 cm(2), p < 0.001), and (3) the area derived from the Gorlin equation in the 18 patients who underwent catheterization (1.27 +/- 0.35 cm(2), mean difference = 0.19 +/- 0.16, y = 0.98x + 0.05, r = 0.81, SEE = 0.26 cm(2), p < 0.001). CONCLUSIONS: These findings suggest that Doppler color flow imaging of the MS jet in the vena contracta can provide an accurate estimation of MVA and appears to be potentially applicable in the assessment of the severity of MS. 相似文献
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Namik Kemal Eryol Ramazan Topsakal Abdurrahman Oguzhan Adnan Abaci Emrullah Baar Ali Ergin Servet etin 《Annals of noninvasive electrocardiology》2002,7(3):242-246
Background: The ventricular late potential (VLP) detected using the technique of signal average electrocardiography (SAECG) interacts with several factors, primarily time. Method: In this study, we examined the interaction, over time, of VLP with the initial ischemic burden and enzyme levels in acute myocardial infarction. Patients diagnosed as having acute myocardial infarction were included in the study. On the first day, the patients underwent enzyme analysis and electrocardiography (ECG) follow‐up every 6 hours. A 24‐hour ambulatory ECG was performed on the seventh day in order to determine the ischemic burden. SAECG findings (TQRS, RMS, LAS were obtained on the seventh day, in the first and third months. The study was continued with the patients who did not require angioplasty as decided with angiographic evaluation in the first month. Results: The study included 30 patients with acute myocardial infarction (mean age 51 ± 12, 28 males and 2 females). The initial mean CK‐MB levels and the mean ischemic burden were 98 ± 31 U/L and 44 ± 96 minutes. The TQRS (ms), LAS (ms), and RMS (μV) values (mean ± SD) obtained at day 7, month 1, and month 3 are 97 ± 12, 96 ± 9, 103 ± 11, P = 0.01; 31 ± 10, 31 ± 11, 32 ± 10, P = 0.46; 43 ± 28, 41 ± 26, 33 ± 25, P = 0.01, respectively. We observed that the TQRS and RMS values changed significantly with time, but these levels of significance disappeared when adjusted for the initial ischemic burden and CK‐MB levels (P = 0.06; P = 0.53). The VLP frequency was 33% at day 7 and 23% at month 3. Unlike the CK‐MB level, the initial ischemic burden was significantly different between the patients with and without VLP at month 3 (150.85 ± 149.28, 12.34 ± 26.48, P = 0.001). When tested together with age and gender, it was found that the high initial ischemic burden increased the possibility of VLP (OR: 24, Cl: 2.09–279.52, P = 0.01) at month 3. Conclusion: SAECG findings in patients with myocardial infarction changed with time; however, this change occurred depending on the initial ischemic burden and CK‐MB levels. Of these, only the initial ischemic burden, especially in high levels, was a determinant for the presence of VLP in the late period of myocardial infarction. A.N.E. 2002;7(3):242–246 相似文献
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Alexis Guédon Stéphanie Condette-Auliac Arturo Consoli Federico Di Maria Oguzhan Coskun Georges Rodesch 《Journal of neuroradiology. Journal de neuroradiologie》2021,48(1):16-20
We report an anatomical-based association between conus medullaris pial arteriovenous shunt that drain caudally towards the lumbosacral area with very delayed onset of an acquired lumbar epidural shunt, draining secondarily towards intradural veins and responsible for a venous congestive myelopathy with identical clinical symptoms. These patients require close clinical and imaging follow-ups in order to propose adequate treatments before onset of irreversible neurological deficits. MRA should include the lumbo-sacral area in its field of view. 相似文献
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Ulgey Melih Gorler Oguzhan Karahan Gunduz Cansu 《Odontology / the Society of the Nippon Dental University》2021,109(4):845-853
Odontology - In the last decade, demand for metal-free esthetic restorations has grown considerably due to the development of materials to fulfill the need for an esthetic prosthesis. We examined... 相似文献
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Oguzhan Deyneli İhsan Nuri Akpınar Özlem Sezgin Meriçliler Hülya Gözü Mehmet Erdem Yıldız Nefise Sema Akalın 《Annales d'endocrinologie》2014