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51.
The use of computed tomography is often debatable for pediatric patients because of the associated radiation exposure. Using a state-of-the-art 64-slice spiral computed tomography unit, we demonstrate the feasibility of lowering the radiation dose without losing essential diagnostic information in a case of a 2-year-old boy with a rare congenital heart defect. 相似文献
52.
Flatau E Trougouboff P Kaufman N Reichman N Luboshitzky R 《European journal of epidemiology》2000,16(1):43-46
The aim of this study was to determine the prevalence of hypothyroidism and diabetes mellitus (DM) in elderly (aged 65–92 years) kibbutz members in Northern Israel. Method: The medical records of 1096 elderly (642 females and 454 males) residing in 11 kibbutzim were reviewed for data regarding thyroid function tests (TSH and FT4) and fasting blood glucose. Fasting blood glucose levels above 7.8 mmol/l was considered diagnostic for diabetes mellitus. Results: The prevalence of hypothyroidism was 14% (9.7% in males and 18.2% in females) and that of DM was 11.5% (12.1% in males and 11.1% in females). In 74% of the diabetics the diagnosis was made after the age of 60 years. Distribution of treatment modalities in diabetics was as follows: diet only 42%, oral hypoglycemic agents 52% and Insulin 6%. Subclinical hypothyroidism (serum TSH levels above 4.5 mU/L with normal FT4 levels) was detected in 38% of all the hypothyroid subjects. Conclusion: The data suggest that diabetes mellitus and primary hypothyroidism are common disorders in elderly subjects. DM in the elderly can usually be handled with diet and oral hypoglycemic drugs. Since the clinical features of hypothyroidism in the elderly are often atypical, we suggest that elderly subjects should be screened for hypothyroidism. 相似文献
53.
BACKGROUND: Members of the estuarine dinoflagellate genus Pfiesteria are reported to have been responsible for massive fish kills in the southeastern United States. Some reports suggest that exposure to waters having Pfiesteria blooms or occupation-related exposure might result in Pfiesteria-induced dermal irritation and inflammation. Although the toxin has not been isolated and purified, the original data suggested both hydrophilic and hydrophobic toxic components. Some investigators propose that dermonecrotic properties are associated with a hydrophobic fraction. OBJECTIVES: A bioactive C18-bound putative toxin (CPE) extracted from Pfiesteria-laden aquarium water during active fish-killing conditions was examined in the present study to evaluate its potential to produce inflammation and dermal sensitization and to determine whether the inflammation and dermatitis reported in early human exposure studies were allergic or irritant in nature. RESULTS: This fraction was cytotoxic to mouse Neuro-2A cells and primary human epidermal keratinocytes (NHEK) at a concentration of 1 mg/mL. Balb/C mice exposed to 50-200% CPE by skin painting exhibited a 6-10% increase in ear swelling relative to vehicle-treated mice in a primary irritancy assay. There was no increase in lymph node cell proliferation as measured using the local lymph node assay. Exposure to CPE in culture up-regulated interleukin-8 in NHEK, whereas granulocyte macrophage-colony-stimulating factor and tumor necrosis factor alpha were only minimally altered. CONCLUSIONS: This study suggests that CPE is cytotoxic to keratinocytes in culture at high concentrations and that it induces mild, localized irritation but not dermal sensitization. 相似文献
54.
Noura A. Alsufyani Michelle L. Noga Manisha Witmans Paul W. Major 《Oral Radiology》2017,33(3):161-169
Objective
To review recent use of three-dimensional (3D) imaging, specifically cone-beam computed tomography (CBCT), in the analysis of the upper airway for diagnosis or treatment outcomes in patients with sleep-disordered breathing (SDB).Types of studies reviewed
Literature review of relevant medical and dental studies utilizing 3D imaging to assess the upper airway.Results
Imaging of the upper airway provided insight into potential areas of obstruction. Accessibility of CBCT to dentists is reflected in several applications of upper airway diagnosis, treatment planning, and different treatment outcomes, as well as association with craniofacial development. However, multiple deficiencies in image acquisition, 3D reconstruction, and analysis are evident.Practical implications
The role of CBCT in the analysis of the upper airway is growing; however, critical limitations remain. An understanding of these limitations, clarification of misconceptions, and improvements in analysis methods are required to ensure proper use and development of CBCT.55.
Dagan R Givon-Lavi N Zamir O Sikuler-Cohen M Guy L Janco J Yagupsky P Fraser D 《The Journal of infectious diseases》2002,185(7):927-936
A double-blind, randomized study involving 264 toddlers attending day care centers was conducted to document the effect of a 9-valent pneumococcal conjugate vaccine on the carriage rate of pneumococci. Of 3750 cultures done on nasopharyngeal samples obtained from subjects during a 2-year follow-up period after vaccination, 65% were positive for Streptococcus pneumoniae. In all age windows, the rate of carriage of vaccine-type pneumococci was lower among subjects who received the pneumococcal vaccine than among control subjects, because the acquisition rate was lower in the former group. The effect was most pronounced among subjects aged < or =36 months. The sample size enabled us to study protection against carriage of S. pneumoniae serotypes 6B, 9V, 14, 19F, and 23F; significant protection against all serotypes except 19F was seen in the pneumococcal-vaccine group. The rate of carriage of serotype 6A (not included in the vaccine) was also reduced significantly, but the rate of carriage of serotype 19A (not included in the vaccine) was not. The rate of carriage of non-vaccine-type pneumococci (excluding serotype 6A) was higher in the pneumococcal-vaccine group than in the control group. 相似文献
56.
Otto-Knapp R Conrad F Hösch S Metzenauer P Maus J Noga O Petzold U Kunkel G 《Pulmonary pharmacology & therapeutics》2008,21(1):47-53
BACKGROUND & OBJECTIVE: Because of environmental concerns CFC-containing pressurised metered dose inhalers (pMDI) had to be replaced by dry powder inhalers (DPI). The Novolizer, a novel DPI has previously been shown to be as effective as the Turbuhaler in delivering budesonide. The objective of this study was to show non-inferiority of inhaled formoterol therapy delivered through the Novolizer compared to formoterol delivered through the Aerolizer in patients suffering from moderate to severe asthma. METHODS: In this double-blind, double-dummy, multicentre study 392 patients were randomised and received a dose of 12 microg formoterol twice daily for 4 weeks either through the Aerolizer or the Novolizer. FEV1 after 4 weeks of treatment was the primary variable. Secondary variables were FVC, PEF, consumption of short-acting; 2 adrenoceptor agonists, asthma symptoms, tolerability and safety. RESULTS: After 4 weeks of treatment, the mean trough FEV1 (95% CI) was 2.34 L (2.24-2.45) for the Novolizer and 2.31 L (2.21-2.41) for the Aerolizer. Non-inferiority was proven (p<0.0001, pre-defined; of 0.25 L). All secondary variables (incl. PEF) confirmed these findings. Treatment with both devices was safe and well tolerated. CONCLUSION: Inhalation of 12 microg formoterol twice daily via Novolizer was shown to be equally therapeutically effective compared to the inhalation via Aerolizer in the treatment of moderate to severe persistent asthma. Treatment via both inhalers was safe and well tolerated. 相似文献
57.
Tomasz Skrzekut Grzegorz Boczkal Adam Zwoliski Piotr Noga Lucyna Jaworska Pawe Paka Marcin Podsiado 《Materials》2021,14(13)
Zr-2.5Cu and Zr-10Cu powder mixtures were consolidated in the extrusion process and using the spark plasma sintering technique. In these studies, material tests were carried out in the fields of phase composition, microstructure, hardness and tensile strength for Zr-Cu materials at room temperature (RT) and 400 °C. Fractography analysis of materials at room temperature and 400 °C was carried out. The research took into account the anisotropy of the materials obtained in the extrusion process. For the nonequilibrium SPS process, ZrCu2 and Cu10Zr7 intermetallic compounds formed in the material at sintering temperature. Extruded materials were composed mainly of α-Zr and ZrCu2. The presence of intermetallic compounds affected the reduction in the strength properties of the tested materials. The highest strength value of 205 MPa was obtained for the extruded Zr-2.5Cu, for which the samples were cut in the direction of extrusion. For materials with 10 wt.% copper, more participation of the intermetallic phase was formed, which lowered the mechanical properties of the obtained materials. In addition to brittle intermetallic phases, the materials were characterized by residual porosity, which also reduced the strength properties. 相似文献
58.
Tomasz Skrzekut Andrzej Piotrowicz Piotr Noga Maciej Wdrychowicz Adam W. Bydaek 《Materials》2022,15(11)
Recovery of zinc and manganese from scrapped alkaline batteries were carried out in the following way: leaching in H2SO4 and selective precipitation of zinc and manganese by alkalization/neutralization. As a result of non-selective leaching, 95.6–99.7% Zn was leached and 83.7–99.3% Mn was leached. A critical technological parameter is the liquid/solid treatment (l/s) ratio, which should be at least 20 mL∙g−1. Selective leaching, which allows the leaching of zinc only, takes place with a leaching yield of 84.8–98.5% Zn, with minimal manganese co-leaching, 0.7–12.3%. The optimal H2SO4 concentration is 0.25 mol∙L−1. Precipitation of zinc and manganese from the solution after non-selective leaching, with the use of NaOH at pH = 13, and then with H2SO4 to pH = 9, turned out to be ineffective: the manganese concentrate contained 19.9 wt.% Zn and zinc concentrate, and 21.46 wt.% Mn. Better selectivity results were obtained if zinc was precipitated from the solution after selective leaching: at pH = 6.5, 90% of Zn precipitated, and only 2% manganese. Moreover, the obtained concentrate contained over 90% of ZnO. The precipitation of zinc with sodium phosphate and sodium carbonate is non-selective, despite its relatively high efficiency: up to 93.70% of Zn and 4.48–93.18% of Mn and up to 95.22% of Zn and 19.55–99.71% Mn, respectively for Na3PO4 and Na2CO3. Recovered zinc and manganese compounds could have commercial values with suitable refining processes. 相似文献
59.
Using standard immunohistochemical and histochemical techniques, we have examined the neurochemical characteristics of a subpopulation of locomotor-related neurons as labeled by the activity-dependent marker c-fos. Results were compared to those obtained from a small sample of intracellulariy labeled locomotor-related neurons. In the paralyzed, decerebrate cat, fictive locomotion was evoked by electrical stimulation of the mesencephalic locomotor region. Most c-fos-immunoreactive neurons were distributed in medial lamina VI and VII and in lamina VIII and X. Double labeling of c-fos with various cytochemical markers revealed that about one-third of the c-fos-immunoreactive neurons were choline acetyltransferase immtmoroactive, about one-third were glutamate immunoreactive, and about one-third were aspartate immunoreactive. In addition, approximately 15% of the c-fos-labeled neurons contained NADPH-diaphorase reaction product, while almost 40% appeared to receive close contacts from calcitonin generelated peptide-immunoreactive fibers and boutons. Choline acetyfransferase- or aspartate immunoreactivity was observed in some intracellulariy, labeled neurons. These findings have implications regarding the putative neurotransmitters utilized by subpopulations of locomotor-related neurons in the cat spinal cord. 相似文献
60.
B. Skoog B. R. Noga 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1995,105(1):39-47
The effects of dopamine and its agonists on transmission from muscle afferents to spinal neurones were investigated in the cat and guinea-pig spinal cord, by measuring the drug effects on the amplitude of monosynaptic field potentials evoked by electrical stimulation of group I and group II muscle afferents. Local iontophoretic application of dopamine, the dopamine D1/D5 agonist SKF-38393 and the D2/D3/D4 agonist quinpirole all depressed the group II field potentials evoked at the base of the dorsal horn. Group II field potentials in the intermediate zone were depressed by dopamine to a similar degree as the dorsal horn field potentials, whereas the dopamine agonists were without effect upon them. The intermediate zone field potentials evoked by group I muscle afferents were not depressed by any of the drugs. The dopamine-evoked depression of the group II-evoked field potentials in the dorsal horn in the guinea-pig spinal cord was reduced by the simultaneous application of haloperidol. The results demonstrate that dopamine receptors mediate the depression of transmission from group II muscle afferents to interneurones in the dorsal horn, but not to neurones in the intermediate zone of the spinal cord. 相似文献