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91.
92.
Purpose There is growing interest in the human sodium/iodide symporter (NIS) gene both as a molecular imaging reporter gene and as a therapeutic gene. Here, we show the feasibility of radioisotope therapy of neuroendocrine tumors. As a separate application of NIS gene transfer, we image NIS-expressing tumors with pinhole SPECT in living subjects. Methods Biodistribution studies and in vivo therapy experiments were performed in nude mice carrying stably NIS-expressing neuroendocrine tumor xenografts following i.v. injection of 131I and 99mTc pertechnetate. To show the usefulness of NIS as an imaging reporter gene, 99mTc pertechnetate uptake was imaged in vivo using a clinical gamma camera in combination with a custom-made single pinhole collimator, followed by SPECT/small animal MRI data coregistration. Results NIS-expressing neuroendocrine tumors strongly accumulated 131I and 99mTc pertechnetate, as did thyroid, stomach, and salivary gland. The volume of NIS-expressing neuroendocrine tumors decreased significantly after therapeutic administration of 131I or 99mTc pertechnetate, whereas control tumors continued to grow. NIS-mediated uptake of 99mTc pertechnetate could be imaged in vivo at high resolution with a clinical gamma camera equipped with a custom-made single pinhole collimator. High-resolution functional and morphologic information could be combined in a single three-dimensional data set by coregistration of SPECT and small animal MRI data. Lastly, we demonstrated a therapeutic effect of 99mTc pertechnetate on NIS-expressing neuroendocrine tumors in cell culture and, for the first time, in vivo, thought to be due to emitted Auger and conversion electrons. Conclusions NIS-expressing neuroendocrine tumors efficiently concentrate radioisotopes, allowing for in vivo high-resolution small animal SPECT imaging as well as rendering possible successful radioisotope therapy of neuroendocrine tumors.  相似文献   
93.
Archives of Virology - The sequences encoding the haemagglutinin (HA) of twelve H5N1 isolates obtained in 2006 and 2007 from different avian species in backyard holdings and poultry farms in Egypt...  相似文献   
94.
Background:  The development and the quantitative relationship between allergen-specific IgE (S-IgE) responses and total IgE (T-IgE), during childhood and adolescence have not been described and understood in detail. The objective of this study was to describe and compare the longitudinal trends of serum levels of S-IgE and T-IgE during childhood.
Methods:  We analysed data from participants in the MAS birth cohort study at 2, 5, 7 and 10 years of age ( n  = 273) and at 1, 3, 5, 6, 7, 10 and 13 years ( n  = 84). Total-IgE and the overall level of specific-IgE against nine locally relevant airborne and food allergens were determined by FEIA (ImmunoCAP). Allergic rhino-conjunctivitis and asthma were ascertained by questionnaires.
Results:  Longitudinal patterns of T-IgE levels from age 1 to 13 years were highly heterogeneous (declining, flat or increasing with different profiles). From 5 years of age, logarithmic (log10) transformed values of T-IgE and of S-IgE levels tend to follow a parallel trend, so that their relation remained constant throughout school age. A flat trend of T-IgE vs a constantly increasing trend of T-IgE was associated with a low or, respectively, high rate of wheezing at 13 years of age.
Conclusions:  Beginning at the age of 5 years, total serum IgE levels in children from an industrialized country evolved in parallel with overall S-IgE levels. Therefore, variations in T-IgE levels at school age closely reflect variations in overall S-IgE levels. Further studies are required to strengthen the biological and clinical implication of this novel finding.  相似文献   
95.
96.
According to the literature, differences in torsion of 15 degrees and more develop in 20-30% of cases after intramedullary nailing of femoral shaft fractures. A computer-assisted method makes it possible to determine the antetorsion angle during surgery. In this experimental study, the precision of the measurements obtained with the navigation system were checked with a femur model and compared with a CT reference method. The measurements are carried out on a femur model that is equipped with a rotation device in the middle of the shaft. Nine reproducible angles can be set. Two investigators each conduct the measurements of the antetorsion angle ten times. A comparison is drawn between the absolute values of the antetorsion angle measured and the difference values of the adjoining positions.When comparing the absolute values of the navigation and reference systems, the mean deviations of both methods are around 1 degrees (0.35; 1.75) and comparing the differences 0.5 degrees (-0.2; 1.17). The maximum deviation of the absolute values of the CT reference method amounts to 6.4 degrees . Under experimental conditions, measurement of the femoral antetorsion angle proved to be sufficiently precise for clinical specifications in comparison to a CT reference method.  相似文献   
97.
High-arousing emotional stimuli facilitate early visual cortex, thereby acting as strong competitors for processing resources in visual cortex. The present study used an electrophysiological approach for continuously measuring the time course of competition for processing resources in the visual pathway arising from emotionally salient but task-irrelevant input while performing a foreground target detection task. Steady-state visual evoked potentials (SSVEPs) were recorded to rapidly flickering squares superimposed upon neutral and emotionally high-arousing pictures, and variations in SSVEP amplitude over time were calculated. As reflected in SSVEP amplitude and target detection rates, arousing emotional background pictures withdrew processing resources from the detection task compared with neutral ones for several hundred milliseconds after stimulus onset. SSVEP amplitude was found to bear a close temporal relationship with accurate target detection as a function of time after stimulus onset.  相似文献   
98.
BACKGROUND: It was discovered that Skin Cap (Cheminova Internacional S.A., Madrid, Spain), an over-the-counter psoriasis therapy with zinc pyrithione, contained clobetasol propionate and it was withdrawn from the market by the US Food and Drug Administration review. Some suggested that there might be a synergistic effect of zinc pyrithione with clobetasol propionate. OBJECTIVE: We sought to evaluate the efficacy of clobetasol propionate 0.05% foam with and without the coadministration of a topical 0.25% zinc pyrithione spray in treating psoriasis involving sites other than the scalp. METHODS: We conducted a randomized, double-blind, right/left study of patients with mild to moderate, generally symmetric, plaque-type psoriasis. Patients were assigned to treatment with clobetasol propionate foam on all psoriatic lesions and then randomly assigned to use zinc pyrithione spray to either the right or left side of their body (vehicle spray to be applied to the opposite side). There was a 2-week treatment phase (visits at baseline, week 1, and week 2) and a follow-up phase (visit at week 4), and all treatments were administered twice daily for 2 weeks. The primary outcome measure was the change from baseline to week 2 in the composite score of the signs of psoriasis (erythema, scaling, plaque thickness) for symmetric target lesions. RESULTS: A total of 25 patients were enrolled; 24 completed the trial and 1 was lost to follow up. Of those who completed the study, 63% (15 of 24) were men, and the mean age (+/-SD) was 50 years (+/-12.2). After 2 weeks of therapy, the average decline in the composite score was 3.5 (+/-1.8) for monotherapy (clobetasol propionate foam and vehicle) and, similarly, 3.3 (+/-1.8) for clobetasol propionate foam plus zinc pyrithione spray (P =.5). DISCUSSION: Zinc pyrithione spray does not appear to enhance the efficacy of clobetasol propionate foam after 2 weeks of therapy.  相似文献   
99.
BACKGROUND: Due to the growing use of artificial respiration in amyotrophic lateral sclerosis (ALS), physicians are increasingly confronted with patients seeking discontinuation of therapy. Yet there are few systematic investigations of the withdrawal of ventilation therapy. PATIENTS AND METHODS: In a retrospective investigation of nine German ALS patients, clinical data were recorded from the discontinuation of noninvasive ventilation (n=4) and mechanical ventilation (n=5). RESULTS: In cases of residual spontaneous breathing, intensified symptom control of dyspnea and anxiety was possible with intravenous morphine sulfate at a low dose rate (10 mg/h) but high cumulative dose (185-380 mg). The terminal phase after removing the mask was protracted (22:10 h to 28:00 h). In cases of minimal or absent spontaneous breathing the disconnection was realized in deep sedation, which required a moderate total dose of morphine sulfate (120 mg) but a high dosage rate (up to 300 mg/h). The terminal phase in deep sedation was short (15-80 min). CONCLUSION: The elective termination of ventilation requires differentiated pharmacologic palliative care. More controlled studies are required in order to establish evidence-based guidelines for the termination of ventilation.  相似文献   
100.
Perfluorinated hydrocarbons have been manufactured for over 40 yr and have numerous applications in industry. This group of compounds has recently generated much interest, as some of these compounds such as perfluorooctane sulfonate (PFOS) and perfluoroctanic acid (PFOA) are persistent in the environment and detectable in blood samples of both wildlife and humans. Studies show that these perfluorinated compounds induce peroxisomal proliferation, induce hepatomegaly, alter steroidogenesis, and decrease body weight, accompanied by a wasting syndrome; however, effects on immune function have not been addressed at length. This study examined sulfluramid, a perfluorinated pesticide that is currently available in the marketplace and is a representative member of this class of chemicals. Adult female B6C3F1 mice were exposed via gavage to either an oil carrier control or sulfluramid for 14 d (1, 3, 10, or 30 mg/kg/d) or 28 d (0.3, 1, 3, or 10 mg/kg/d). Although responses were normal in natural killer cell activity and lymphocyte proliferation, dose-responsive suppression was noted in the plaque forming cell (PFC) response at exposure levels as low as 3 mg/kg/d in the 14-d exposure and 0.3 mg/kg/d for 28 d. Dose-responsive increases in liver mass were observed following treatment with 1, 3, 10, or 30 mg/kg/d for 14 d and 0.3, 1, 3, or 10 mg/kg/d for 28 d. A significant reduction in body weight was observed at the highest dose level in each study. Novel findings in this study indicate that sulfluramid suppresses immunoglobulin (Ig) M production. Additional immunotoxicity studies are required to understand potential mechanisms of suppression and determine potential health risks associated with exposure to perfluorinated hydrocarbons.  相似文献   
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