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91.
92.

Purpose  

An angiographic evaluation combined with 99mTc-macroaggregated albumin (Tc-MAA) scanning should precede the treatment of any selected candidates for radioembolization (RE) of the liver. If the tumours in one liver lobe have not been targeted in the test angiogram, it should be repeated. However, in a few cases treatment of one liver lobe or at least some segments is safe and feasible and performing a repeated test angiogram with Tc-MAA (Re-MAA) in a separate session leads to more radiation exposure and could be time consuming. Our aim was to evaluate the feasibility of concurrent RE of a part of the liver and therapy planning for another region by simultaneous injection of the Tc-MAA and 90Y-microspheres in two different locations in the therapy session. Tc-MAA and bremsstrahlung (BS) single photon emission computed tomography (SPECT)/CT were performed separately in an effort to distinguish between the distributions of these two different radiopharmaceuticals.  相似文献   
93.

Purpose  

While influx of chemoembolic agents into the hepatic falciform artery (HFA) from the hepatic artery can cause supraumbilical skin rash, epigastric pain and even skin necrosis, the significance of a patent HFA in patients undergoing radioembolization is not completely clear. Furthermore, the presence of tracer in the anterior abdominal wall seen in 99mTc-macroaggregated albumin (99mTc-MAA) images, which is generally performed prior to radioembolization, has been described as a sign of a patent HFA. The aim of this retrospective study was to evaluate the incidence and consequences of 99mTc-MAA accumulation in the anterior abdominal wall, indicating a patent HFA, in patients undergoing radioembolization of liver tumours.  相似文献   
94.
The E-selectin mediates the interaction of activated endothelial cells with leukocytes and plays a fundamental role in the pathogenesis of asthma. It has been suggested that an S/R (Serine128Arginine) polymorphism of E-selectin alters ligand binding function. Our purpose in this study was to determine whether this Serine128Arginine polymorphism influences the risk of asthma and also to analyze the possible correlation of disease severity in Iranian patients with polymorphism of E-selection. We studied human E-selectin gene polymorphism in 172 asthmatic patients and 173 healthy volunteers by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). To determine the severity of the asthma's situation, a questionnaire was prepared requesting the following information: age, sex, clinical signs and symptoms and past medical history. After the participants filled in the questionnaire, all active or ex-smoker patients were excluded. A trained observer assessed airway reversibility, peak flowmetry and spirometry in asthmatic patients. We found increased serum levels of soluble E-selectin (sE-selectin) in asthmatic patients compared with healthy subjects (P<0. 0001). Frequencies of the SS, SR, and RR genotypes were found as 66.3%, 31.4%, and 2.3% in the patients and 91.9%, 8.1%, and 0.0% in control subjects, respectively. The 128Arg allele was more prevalent in patients than controls (OR 5.78; 95% CI, 3.07-10.86, P<0.0001). However, in this study the polymorphism was not associated with circulating sE-selectin levels. We found a direct correlation between the level of sE-selectin and the severity of asthma (P=0.001). On the other hand, there was a close relation between 128Arginine carriage and disease severity (P<0.0001). These results suggest that the Ser128Arg polymorphism of the E-selectin gene is a genetic factor that may be associated with the severity of asthma.  相似文献   
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97.
This article presents a new methodology for investigation of the organization of the overall and hemispheric brain network of patients with attention-deficit hyperactivity disorder (ADHD) using theoretical analysis of a weighted graph with the goal of discovering how the brain topology is affected in such patients. The synchronization measure used is the nonlinear fuzzy synchronization likelihood (FSL) developed by the authors recently. Recent evidence indicates a normal neocortex has a small-world (SW) network with a balance between local structure and global structure characteristics. Such a network results in optimal balance between segregation and integration which is essential for high synchronizabilty and fast information transmission in a complex network. The SW network is characterized by the coexistence of dense clustering of connections (C) and short path lengths (L) among the network units. The results of investigation of C show the local structure of functional left-hemisphere brain networks of ADHD diverges from that of non-ADHD which is recognizable in the delta electroencephalograph (EEG) sub-band. Also, the results of investigation for L show the global structure of functional left-hemisphere brain networks of ADHD diverges from that of non-ADHD which is observable in the delta EEG sub-band. It is concluded that the changes in left-hemisphere brain's structure of ADHD from that of the non-ADHD are so much that L and C can distinguish the ADHD brain from the non-ADHD brain in the delta EEG sub-band.  相似文献   
98.
Functionalization of polysulfones by using “Click” chemistry is described for the example of a small fluorescent analyte propargylpyrene. First, PSUs were converted to azido‐functionalized polymers by successive chloromethylation and azidation. Propargylpyrene was prepared independently as a fluorescent click component. Finally, the azido‐functionalized PSUs were coupled with propargylpyrene with high efficiency by copper‐catalyzed azide/alkyne click reactions. The final polymers and intermediates at various stages were characterized by 1H NMR, FT‐IR, GPC, UV‐Vis, and fluorescence spectroscopy techniques.

  相似文献   

99.
100.
Oxidative stress mediated by reactive oxygen species is known to contribute to the inflammatory process of bronchial asthma. Reactive oxygen species are released into the bronchial tree by activated inflammatory cells. In this study, we aimed to determine the effect of vitamin C administration on leukocyte vitamin C level as well as severity of asthma. In this double blind clinical trial study we evaluated 60 patients with chronic stable asthma. The patients were divided into two groups (A and B) including 30 patients in each group. Patients in these groups were matched according to their age, weight, height, gender, BMI and drug consumption. In addition to standard asthma treatment (according to stepwise therapy in 4th step of bronchial asthma) in which the patients were controlled appropriately, group A received 1000 mg vitamin C daily and group B received placebo. At the baseline and after one month treatment, non-fasting blood samples were drawn for laboratory evaluations. Asthmatic patient's clinical condition was evaluated through standard pulmonary function test (PFT). The mean (±SD) leukocyte vitamin C level in group A at the baseline and after one month treatment with 1000 mg/day vitamin C, were 0.0903 (±0.0787) μg/108 leukocytes and 0.1400 (±0.0953) μg/108 leukocytes respectively (P<0.05). The mean (±SD) leukocyte vitamin C level in group B at the baseline and after one month administration of placebo, were 0.0867 (±0.0629) μg/108 leukocytes and 0.0805(±0.0736) μg/108 leukocytes respectively. The leukocyte vitamin C level in group A was higher than those of group B after one month treatment with vitamin C and placebo and the difference was statistically significant (P<0.05). Comparing PFT (FEV1, FVC and FEV1/FVC) in group B during the study period showed a significant increase in FEV1 (P<0.05), while the other two parameters remained unchanged. In group A, who received 1000 mg/day vitamin C, none of the spirometry parameters changed after one month treatment, indicating no effect of vitamin C treatment in the spirometry parameters.  相似文献   
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