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101.
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The dosage of (131)I for the treatment of metastatic well-differentiated thyroid cancer is typically selected empirically. Benua and Leeper implemented a method to estimate the maximum dosages of (131)I that could be administered to a patient so as not to exceed a maximum tolerated radiation absorbed dose (MTD), which was defined as 200 rads (cGy) to the blood. The objective of this study was to determine the frequency of (131)I treatments in which the patient (1) would have exceeded the MTD (i.e., overtreatment) or (2) would have been able to receive higher dosages of (131)I thereby delivering a potentially higher radiation absorbed dose to their metastases (i.e., undertreatment) had the patient been administered various assumed empiric dosages of (131)I. The dosimetrically- determined maximum tolerated radioactivities (MTA) to deliver 200 rads to the blood (MTD) were tabulated at our facility. Data were then grouped to determine the percentage of patients who would have received less than or more than the MTD for various assumed empiric dosages of (131)I. A total of 127 dosimetries were performed. For assumed empiric dosages of (131)I (100 mCi, 150 mCi, 200 mCi, 250 mCi, and 300 mCi), the percentage of treatments for which patients would have exceeded the MTD were less than 1%, 5%, 11%, 17%, and 22%, respectively, and could have received a higher dosage of (131)I were more than 99%, 95%, 89%, 83%, and 78%, respectively. A significant number of patients receiving various empiric dosages of (131)I may exceed 200 rads (cGy) to the blood (potential overtreating). Likewise, the majority of patients may be able to receive much higher dosages of (131)I relative to empiric dosages thereby delivering potentially higher radiation absorbed doses to the metastases without exceeding 200 rads (cGy) to the blood (potential undertreating).  相似文献   
105.
Vena caval obstruction may cause significant morbidity after intraatrial repair of transposition of the great arteries (TGA). Two noninvasive methods of diagnosing vena caval obstruction were compared with cardiac catheterization. Echocardiographically gated magnetic resonance imaging (MRI) and echocardiographic evaluation (2-dimensional saline contrast echocardiography and pulsed Doppler flow measurement) were performed on 15 patients 0.7 to 13.5 years after intraatrial repair of TGA (8 Mustard, 7 Senning). At catheterization, complete superior vena cava or partial caval obstruction (gradient greater than 5 mm Hg from cava to systemic venous atrium) was present in 7 of 15 patients. Superior vena cava obstruction was directly visualized by MRI in both patients with catheterization-proved complete superior vena cava occlusion. A dilated azygous/hemiazygous venous complex (greater than or equal to 5 mm cross-sectional diameter) was seen by MRI in 5 of 7 patients with complex or partial vena caval obstruction and in no patient without vena caval obstruction. MRI showed superior vena caval dilatation (ratio of superior vena caval diameter to aortic diameter greater than 1.45) in 3 of 5 patients with partial vena caval obstruction and in 0 of 8 without vena caval obstruction. Direct visualization of narrowing within the atrium was unreliable for any MRI plane because of the 3-dimensional nature of the intraatrial baffle. Two-dimensional saline contrast echocardiography, successfully performed in 12 of 15 patients, detected complete superior vena caval obstruction only in the 2 patients with catheterization-proved complete superior vena cava occlusion. Contrast echocardiography failed to identify any of the 5 patients with partial vena caval obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
106.

Aim

To study the knowledge, attitude, and practices of antenatal women regarding nutrition and drug compliance in a maternal and child health center in Navi Mumbai.

Material and Methods

This study was carried out on 250 pregnant females visiting a maternal and child health center over a period of 4 months from November 2012 to February 2013. Women attending the antenatal OPD were asked to fill a questionnaire regarding anemia so as to test their knowledge, attitudes, and practices pertaining to anemia and role of their diet.

Observation

The observations were analyzed. This study reflects the ignorance and lack of education among the majority of child-bearing women of low socioeconomic class.

Conclusion

Educating antenatal women about the importance of diet and implementing this into practice will help in the prevention of anemia. It is also seen that drug compliance for iron and folic acid (free supply) has significantly improved, not only because of the cost factor but also due to the reinforcement of knowledge by the staff so as to achieve the minimum WHO target hemoglobin of 10.5 g% in all mothers.

Electronic supplementary material

The online version of this article (doi:10.1007/s13224-014-0618-0) contains supplementary material, which is available to authorized users.  相似文献   
107.
Severe GN involves local neutrophil extracellular trap (NET) formation. We hypothesized a local cytotoxic effect of NET-related histone release in necrotizing GN. In vitro, histones from calf thymus or histones released by neutrophils undergoing NETosis killed glomerular endothelial cells, podocytes, and parietal epithelial cells in a dose-dependent manner. Histone-neutralizing agents such as antihistone IgG, activated protein C, or heparin prevented this effect. Histone toxicity on glomeruli ex vivo was Toll-like receptor 2/4 dependent, and lack of TLR2/4 attenuated histone-induced renal thrombotic microangiopathy and glomerular necrosis in mice. Anti–glomerular basement membrane GN involved NET formation and vascular necrosis, whereas blocking NET formation by peptidylarginine inhibition or preemptive anti-histone IgG injection significantly reduced all aspects of GN (i.e., vascular necrosis, podocyte loss, albuminuria, cytokine induction, recruitment or activation of glomerular leukocytes, and glomerular crescent formation). To evaluate histones as a therapeutic target, mice with established GN were treated with three different histone-neutralizing agents. Anti-histone IgG, recombinant activated protein C, and heparin were equally effective in abrogating severe GN, whereas combination therapy had no additive effects. Together, these results indicate that NET-related histone release during GN elicits cytotoxic and immunostimulatory effects. Furthermore, neutralizing extracellular histones is still therapeutic when initiated in established GN.  相似文献   
108.

Background

Myocardial relaxation is impaired in almost all cases with left ventricular diastolic dysfunction (LVDD) and is a strong predictor of cardiovascular and all-cause mortality.

Objectives

This study investigated the feasibility of signal-processed surface electrocardiography (spECG) as a diagnostic tool for predicting the presence of abnormal cardiac muscle relaxation.

Methods

A total of 188 outpatients referred for coronary computed tomography (CT) angiography underwent an echocardiogram for assessment of LVDD. The use of 12-lead spECG for predicting myocardial relaxation abnormalities as identified using tissue Doppler echocardiography was validated with machine-learning approaches.

Results

A total of 188 subjects underwent diagnostic testing, with 133 (70%) showing abnormal myocardial relaxation on tissue Doppler imaging. A 12-lead spECG showed an area under the curve of 91% (95% confidence interval: 86% to 95%) for prediction of abnormal myocardial mechanical relaxation with a sensitivity and specificity of 80% and 84%, respectively. The spECG demonstrated more accurate diagnostic performance in individuals age ≥60 years as well as those with obesity or hypertension, compared with their respective counterparts. Prediction of low early diastolic relaxation velocity (e′) also correctly identified concomitant significant underlying coronary artery disease in 23 of 28 cases (82%). Furthermore, a superior integrated discrimination and net reclassification improvement was observed for spECG over clinical features and traditional ECG.

Conclusions

The spECG provides a robust prediction of abnormal myocardial relaxation. These data suggest a potential role for spECG as a novel screening strategy for identifying patients at risk for LVDD who would benefit undergoing echocardiographic evaluations.  相似文献   
109.
110.

Purpose of the Study:

It is difficult to achieve a reliable bond between the titanium and veneering porcelain. The aim of this study was to evaluate the bond strength between titanium ceramic crowns.

Materials and Methods:

The surfaces of titanium copings were divided in two groups. Group A sandblasted with 250 um (n = 10) and Group B without sandblasting (n = 10). Low-fusing porcelain was bonded over copings. A universal testing machine was used to determine the fracture load (N) of the crowns. All data were compared using Student''s t-test.

Results:

There was a significant difference in fracture toughness between two groups (P = 0.05). The mean value of fracture strength for Group A was 721.66 N and for Group B was 396.39 N.

Conclusions:

Sandblasting improves the bond strength between titanium, and ceramic, mechanical bonding plays a crucial role in the bonding between titanium and ceramic.Key Words: Bonding, fracture load, sandblasting, titanium  相似文献   
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