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21.
The added value of the apparent diffusion coefficient calculation to magnetic resonance imaging in the differentiation and grading of malignant brain tumors 总被引:14,自引:0,他引:14
Bulakbasi N Guvenc I Onguru O Erdogan E Tayfun C Ucoz T 《Journal of computer assisted tomography》2004,28(6):735-746
OBJECTIVE: ADC calculation can improve the diagnostic efficacy of MR imaging in brain tumor grading and differentiation. METHODS: Apparent diffusion coefficient (ADC) values and ratios of 33 low-grade (23 astrocytomas, 10 oligodendrogliomas) and 40 high-grade (25 metastases and 15 high-grade astrocytomas) malignant tumors were prospectively evaluated. RESULTS: Tumoral ADC values (r=-0.738, P <0.000) and ratios (r=-0.746, P < 0.000) were well correlated with higher degree of malignancy and quite effective in grading of malignant brain tumors (P < 0.000). By using cutoff values of 0.99 for tumoral ADC value and 1.22 for normalized ADC ratio, the sensitivity of MR imaging could be increased from 72.22% to 93.75% and 90.63%, the specificity from 81.08% to 92.68% and 90.24%, PPV from 78.79% to 90.91% and 87.88%, and NPV from 75.00% to 95.00% and 92.50%, respectively. CONCLUSION: ADC calculation was quite effective in grading of malignant brain tumors but not in differentiation of them and added more information to conventional contrast-enhanced MR imaging. 相似文献
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IntroductionSubchorionic hematoma (SCH) in pregnancy has been associated with increased risk of adverse pregnancy outcomes. We aimed to investigate the association of SCH with adverse pregnancy outcomes in pregnant women in relation to size of hematoma and control subjects.Material and methodsThis study included 178 pregnant women with sono-graphically detected SCH in the 1st trimester, and 350 pregnant controls without SCH. Data on maternal age, smoking status, gestational week at diagnosis, location of SCH, medications before diagnosis, gestational week at delivery, delivery route and pregnancy outcomes (first trimester vaginal bleeding, pre-eclampsia, gestational diabetes, intrauterine growth restriction (IUGR), placental abruption, preterm delivery < 37 weeks, early pregnancy loss and intrauterine death) were retrieved retrospectively from hospital records. Pregnant women with SCH were divided into 3 groups according to the size of hematoma including small SCH (SCH-I group, n = 47), medium-size SCH (SCH-II group, n = 110) and large SCH (SCH-III group, n = 21) groups.ResultsSubchorionic hematoma was associated with significantly lower gestational age at delivery (p < 0.001) and higher rate of first trimester bleeding (p < 0.001) compared with the control group, regardless of the size of the hematoma. Placental abruption (p = 0.002) and early pregnancy loss (p < 0.001) were significantly more common in SCH-II and -III groups than in the control group. SCH-III group was associated with a significantly higher rate of < 37 gestational weeks at delivery (p < 0.001), first trimester vaginal bleeding (p < 0.001), early pregnancy loss (p < 0.001), IUGR (p = 0.003) and preterm delivery (p < 0.001) compared to both lesser size hematoma and control groups.ConclusionsOur findings suggest that large SCH might indicate an increased risk of adverse pregnancy outcomes such as 1st trimester vaginal bleeding, early pregnancy loss, IUGR, placental abruption or preterm delivery. These findings are important to guide the patients with SCH for detailed clinical evaluation. 相似文献
23.
Gizem Tezel Selin Seda Timur Filiz Kuralay R. Neslihan Gürsoy Kezban Ulubayram Levent Öner 《Journal of drug targeting》2021,29(1):29-45
Abstract Synthetic micro/nanomotors (MNMs) are novel, self-propelled nano or microscale devices that are widely used in drug transport, cell stimulation and isolation, bio-imaging, diagnostic and monitoring, sensing, photocatalysis and environmental remediation. Various preparation methods and propulsion mechanisms make MNMs “tailormade” nanosystems for the intended purpose or use. As the one of the newest members of nano carriers, MNMs open a new perspective especially for rapid drug transport and gene delivery. Although there exists limited number of in-vivo studies for drug delivery purposes, existence of in-vitro supportive data strongly encourages researchers to move on in this field and benefit from the manoeuvre capability of these novel systems. In this article, we reviewed the preparation and propulsion mechanisms of nanomotors in various fields with special attention to drug delivery systems. 相似文献
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Zuhal Aydan Saglam Baris Demir Esra Hayriye Ataoglu Mustafa Yenigun Levent Umit Temiz Tayyibe Saler 《Zeitschrift fur Gesundheitswissenschaften》2012,20(1):59-63
Aim
Acute poisoning is one of the major topics in emergency medicine practices. Despite the recent developments in toxicology, technological advances and changing lifestyles reveal new factors, and poisoning cases remain to be a problem. All poisonings should be considered serious and independent from their clinical presentation at the time of admission. Identifying the cause and prompt initiation of treatment is life-saving. Causes of poisoning vary between countries and different regions of the same country. In the present study, cases admitted to the Emergency Department of Internal Medicine at Haseki Training and Research Hospital were evaluated and causes of acute poisoning were investigated. 相似文献25.
Right ventricular free‐wall longitudinal speckle tracking strain in patients with pulmonary arterial hypertension under specific treatment
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Taner Y?lmaz Münir Demir Bajin R?za ?nder Günayd?n Serdar ?zer Tevfik S?zen 《World journal of gastroenterology : WJG》2014,20(27):8964-8970
Laryngopharyngeal reflux (LPR) occurs when gastric contents pass the upper esophageal sphincter, causing symptoms such as hoarseness, sore throat, coughing, excess throat mucus, and globus. The pattern of reflux is different in LPR and gastroesophageal reflux. LPR usually occurs during the daytime in the upright position whereas gastroesophageal reflux disease more often occurs in the supine position at night-time or during sleep. Ambulatory 24-h double pH-probe monitoring is the gold standard diagnostic tool for LPR. Acid suppression with proton pump inhibitor on a long-term basis is the mainstay of treatment. Helicobacter pylori (H. pylori) is found in many sites including laryngeal mucosa and interarytenoid region. In this paper, we aim to present the relationship between LPR and H. pylori and review the current literature. 相似文献
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