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41.
Kartagener's syndrome (KS) usually includes mirror-image dextrocardia. The incidence of congenital heart disease in KS is comparable with that in the general population. This paper reports on a case of Kartagener's syndrome associated with dextrocardia, corrected transposition of the great arteries (I,D,D), ventricular septal defect, and valvar pulmonary stenosis in an 8-year-old girl. 相似文献
42.
MP Scolnik MF Palacios SH Acevedo MV Castuma IB Larripa A Palumbo EB Moiraghi AM Sasot AB Huberman 《Canadian Metallurgical Quarterly》1998,31(1-2):231-236
The murine monoclonal antibody A7 (MAb A7) is reactive against most human gastric cancer cell lines. Using a nude mouse peritoneal dissemination model of human gastric cancer, we investigated targeted chemotherapy using a conjugate of neocarzinostatin (NCS) with MAb A7 (A7-NCS). After demonstrating cytotoxicity of the complex against the human gastric cancer cell line MKN45 in vitro, we intraperitoneally injected A7-NCS, NCS or saline into nude mice bearing peritoneally disseminated human gastric cancer. A7-NCS inhibited peritoneal dissemination significantly more effectively than NCS. MAb A7 may prove to be an effective carrier for antineoplastic drugs in patients with peritoneal dissemination of gastric cancer. 相似文献
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RS Hogg AE Weber KJ Craib AH Anis MV O'Shaughnessy MT Schechter JS Montaner 《Canadian Metallurgical Quarterly》1998,12(16):2203-2209
OBJECTIVE: To estimate the potential direct cost of making triple combination antiretroviral therapy widely available to HIV-positive adults and children living in countries throughout the world. METHODS: For each country, antiretroviral costs were obtained by multiplying the annual cost of triple antiretroviral therapy by the estimated number of HIV-positive persons accessing therapy. Per capita antiretroviral costs were computed by dividing the antiretroviral costs by the country's total population. The potential economic burden was calculated by dividing per capita antiretroviral costs by the gross national product (GNP) per capita. All values are expressed in 1997 US dollars. RESULTS: The potential cost of making triple combination antiretroviral therapy available to HIV-positive individuals throughout the world was estimated to be over US$ 65.8 billion. By far the greatest financial burden was on sub-Saharan Africa. The highest per capita drug cost in this region would be incurred in the subregions of Southern Africa (US$ 149) followed by East Africa (US$ 116), Middle Africa (US$ 44), and West Africa (US$ 42). In the Americas, subregional data indicated the highest per capita drug cost would be in the Latin Caribbean (US$ 22), followed by the Caribbean (US$ 17), Andean Area (US$ 7), the Southern Cone (US$ 6), North America (US$ 6), and Central American Isthmus (US$ 5). In Asia and Europe the percentage of the GNP necessary to finance drug therapy was less than 1% in most countries examined. CONCLUSION: Our results demonstrate that the cost of making combination antiretroviral therapy available worldwide would be exceedingly high, especially in countries with limited financial resources. 相似文献
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MV Aguilar FJ Jiménez-Jiménez JA Molina I Meseguer CJ Mateos-Vega MJ González-Mu?oz F de Bustos C Gómez-Escalonilla M Ort-Pareja M Zurdo MC Martínez-Para 《Canadian Metallurgical Quarterly》1998,105(10-12):1245-1251
We compared CSF and serum levels of selenium and chromium, measured by atomic absorption spectrophotometry, in 28 patients with Parkinson's disease (PD) and 43 matched controls. The CSF and serum levels of these trace metals did not differ significantly between PD patients and controls. CSF selenium and chromium levels were not correlated with age, age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale of the Hoehn and Yahr staging in the PD group. Although antiparkinsonian therapy did not influence significantly the CSF levels of selenium, PD patients not treated with levodopa had significantly higher CSF selenium levels than controls (p < 0.01). It is possible that increased CSF selenium levels could indicate an attempt of protection against oxidative stress. The normality of CSF and serum chromium levels suggest that these values are not related with the risk for PD. 相似文献
45.
1. The long-acting beta2-adrenoceptor agonist, salmeterol (10(-9)-10(-5) M), inhibited the IgE-mediated release of histamine from human lung mast cells (HLMC) in a dose-dependent fashion. Additional beta-adrenoceptor agonists were studied and the rank order of potency for the inhibition of histamine release from HLMC was isoprenaline > salmeterol > salbutamol. Approximate EC50 values for the inhibition of histamine release were 10 nM for isoprenaline and 100 nM for salbutamol. An EC50 value for salmeterol could not be calculated because maximal responses to salmeterol were not observed over the concentration range employed. 2. Both salmeterol and isoprenaline inhibited the generation of sulphopeptidoleukotrienes (sLT) more potently and more efficaciously than the release of histamine from immunologically-activated HLMC. Salmeterol (EC50 < 0.1 nM) was more potent than isoprenaline (EC50 0.4 nM) at attenuating sLT generation. 3. The beta-adrenoceptor antagonist, propranolol (1 microM), and the selective beta2-adrenoceptor antagonist, ICI 118,551 (0.1 microM), both caused rightward shifts in the dose-response curve for the inhibition of histamine release by isoprenaline. The antagonism of salmeterol effects by propranolol and ICI 118,551 was more complex. At lower concentrations (< 1 microM) of salmeterol, both antagonists shifted the dose-reponse curve to salmeterol rightward. At a higher concentration (10 microM) of salmeterol, neither ICI 118,551 nor propranolol was an effective antagonist of the salmeterol-mediated inhibition of histamine release. 4. Prolonged exposure (4 h) of HLMC to isoprenaline (1 microM) caused an approximately 50% reduction in the effectiveness of a second exposure to isoprenaline (10 microM) at inhibiting the release of histamine. whereas this pretreatment did not affect the salmeterol (10 microM) inhibition of histamine release. 5. Isoprenaline (10(-9)-10(-5) M) caused a dose-dependent increase in total cell cyclicAMP levels in purified HLMC which paralleled the inhibition of histamine release. Salmeterol (10(-9)-10(-5) M) was considerably less potent than isoprenaline at increasing HLMC cyclicAMP levels. 6. In summary, these data indicate that salmeterol is an effective inhibitor of the stimulated release of mediators from HLMC. The present data also suggest that salmeterol may act to inhibit mediator release from HLMC by beta-adrenoceptor-dependent and independent mechanisms. 相似文献
46.
MJ O'Neill JA Lewis HM Noble S Holland C Mansat JE Farthing G Foster D Noble SJ Lane PJ Sidebottom SM Lynn MV Hayes CJ Dix 《Canadian Metallurgical Quarterly》1998,61(11):1328-1331
Methanolic extracts prepared from the leaves of Lantana camara have been found to inhibit human thrombin. An assay, in which thrombin activity is measured as a function of clot formation from fibrinogen, was used to guide the fractionation and purification of five principal active constituents (1-5), which were all characterized as 5,5-trans-fused cyclic lactone-containing euphane triterpenes. 相似文献
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SO Schoenberg MV Knopp M Bock F Kallinowski A Just M Essig H Hawighorst I Zuna L Schad JR Allenberg G van Kaick 《Canadian Metallurgical Quarterly》1997,37(8):651-662
PURPOSE: To evaluate the use of high-temporal resolution cine MR phase-contrast flow measurements for assessment of flow dynamics in renal artery stenosis (RAS). MATERIAL AND METHODS: In a dog model, cine MR flow measurements were validated by comparing the MR flow data to an invasive transit-time ultrasound reference technique for different degrees of RAS. Cardiac-gated MR flow curves were recorded in 56 renal arteries of 28 patients with a temporal resolution of at least 32 ms. In all cases RAS was confirmed by digital subtraction angiography (DSA). Abnormalities of flow dynamics were assessed in the calculated flow curves using the MR parameters mean flow, maximum velocity, and time to systolic maximum. RESULTS: By means of the MR blood flow parameters high-grade stenoses (> 50%, n = 23) were detected with sensitivity of 100% and specificity of 94% with reference to DSA. The overall differentiation between stenoses (n = 37) and non-stenosed vessels (n = 19) revealed a sensitivity of 87% and a specificity of 100%. CONCLUSION: Analysis of cardiac-gated MR flow curves provides a non-invasive method to assess the hemodynamic significance of RAS and thus allows a functional evaluation in relation to the morphologic characteristics of the stenosis. 相似文献