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1.
Minh Thac Nguyen Ryan Denniston Hien Thi Thu Nguyen Tuan Anh Hoang Hana Ross Anthony D. So 《PloS one》2014,9(1)
Illicit trade carries the potential to magnify existing tobacco-related health care costs through increased availability of untaxed and inexpensive cigarettes. What is known with respect to the magnitude of illicit trade for Vietnam is produced primarily by the industry, and methodologies are typically opaque. Independent assessment of the illicit cigarette trade in Vietnam is vital to tobacco control policy. This paper measures the magnitude of illicit cigarette trade for Vietnam between 1998 and 2010 using two methods, discrepancies between legitimate domestic cigarette sales and domestic tobacco consumption estimated from surveys, and trade discrepancies as recorded by Vietnam and trade partners. The results indicate that Vietnam likely experienced net smuggling in during the period studied. With the inclusion of adjustments for survey respondent under-reporting, inward illicit trade likely occurred in three of the four years for which surveys were available. Discrepancies in trade records indicate that the value of smuggled cigarettes into Vietnam ranges from $100 million to $300 million between 2000 and 2010 and that these cigarettes primarily originate in Singapore, Hong Kong, Macao, Malaysia, and Australia. Notable differences in trends over time exist between the two methods, but by comparison, the industry estimates consistently place the magnitude of illicit trade at the upper bounds of what this study shows. The unavailability of annual, survey-based estimates of consumption may obscure the true, annual trend over time. Second, as surveys changed over time, estimates relying on them may be inconsistent with one another. Finally, these two methods measure different components of illicit trade, specifically consumption of illicit cigarettes regardless of origin and smuggling of cigarettes into a particular market. However, absent a gold standard, comparisons of different approaches to illicit trade measurement serve efforts to refine and improve measurement approaches and estimates. 相似文献
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A L Liozner E N Stepanova N A Volynskaia G K Vorkunova A G Bukrinskaia 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(3):91-96
A test system permitting the detection of influenza virus protein M at a concentration of 0.1-0.5 ng/ml in ELISA has been developed. The use of this system made it possible to detect influenza viruses A and B directly in crude virus-containing material and clinical samples obtained from influenza patients. During the outbreak of influenza in the spring of 1983 ELISA was successfully used for the rapid diagnosis of influenza, and some of its advantages in comparison with the conventional immunofluorescence test were thus demonstrated. To overcome difficulties arising from the low immunogenic potency of protein M, in the process of obtaining diagnostic sera and ascitic fluids the animals were immunized with the conjugate of protein M and polyelectrolite, which ensured considerable activation of humoral immune response. 相似文献
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A mathematical model of autoimmunity is developed. This model is a system of two nonlinear differential equations, which describe the concentration dynamics of tissue cells and agressive lymphocytes. An analysis of the solutions shows that this model reproduces general behaviour of autoimmune diseases. 相似文献
6.
Hana Votavová Vladimír Gut Karel Bláha Jaroslav Šponar 《International journal of biological macromolecules》1982,4(6):341-346
DNA complexes with polypeptides (Lys-Ala-Ala)1)] and (Lys-Ala-Ala)34 have been studied using the methods of thermal melting and circular dichroism. Derivative melting curves of (Lys-Ala-Ala)10 DNA differed substantially from those of (Lys-Ala-Ala)34 prepared either by salt gradient dialysis or by direct mixing. Melting curves of the former complex were unimodal or bimodal with Tm increasing continuously withn input lysin-to-DNA phosphate ratio (r); those of the latter complex consisted of three separate transitions with Tm values almost independent of r. Complete reversibility of binding in the (Lys-Ala-Ala)10-DNA system but a slow redistribution of (Lys-Ala-Ala)34 on DNA at low temperature were found in the redistribution experiments Much faster redistribution from denatured to native DNA occurs at the temperature of melting, contributing to the unusual trimodal melting pattern. Circular dichroism curves are very similar for both complexes and indicate little change of DNA conformation upon polypeptide binding. 相似文献
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S V Prozorovski? F M Kirillova L K Stepanova A L Gorelov G A Levina 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(4):24-26
The antigenic structure of the L-forms of salmonellae (S. typhimurium and S. typhi) in comparison with that of the initial bacterial cultures and revertant cultures was studied with the use of the immunoferritin method. The L-forms of salmonellae were found to retain an insignificant amount of O-antigen, as well as to have K-antigen on the surface of the cytoplasmic membrane, but in a lesser amount than the initial strains. In the cultures reverting from the L-forms of S. typhimurium and S. typhi the quantitative and qualitative characteristics of O- and K-antigens were completely restored. 相似文献
9.
František Šťastný Václav Lisý Hana Tomášová Stanislav Trojan 《Neurochemical research》1985,10(6):819-828
Posthypoxic fluctuations in the levels of two excitatory amino acids, glutamate and aspartate, may be related to changes in mechanisms(s) which are responsible for their reuptake. As gamma-glutamyl transpeptidase (GGT) plays a role in mediating the uptake of glutamate and aspartate into various compartments of the brain, we studied changes in the activity of this enzyme in main regions of the brain in young and adult rats. We found a posthypoxic increase in bound GGT activity in some brain regions of 18-day-old animals after acute exposure, but no changes were observed after prolonged altitude hypoxia, with the exception of a decrease in cortical GGT activity. In contrast, acute hypoxia decreased GGT activity in the cortical capillaries to 59%, but prolonged hypoxic exposure was ineffective. However, the activity of soluble GGT in the cerebrospinal fluid of both groups of rats was several-times elevated in comparison with controls. At the same time, bound GGT activity was increased in the liver after acute or prolonged altitude hypoxia. The soluble GGT activity in plasma was only increased after prolonged exposure. Ninety days after prolonged hypoxic exposure the bound GGT activity was reduced in all brain regions to about 60–70% of controls (significantly higher in females than in males) as long-term developmental sequel from early postnatal hypoxia. 相似文献
10.
L I Stepanova S V Kotelevtsev P G Komarov K N Novikov V M Glazer 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1985,(9):27-32
The content of cytochrome P450 and monooxygenase activity has been studied in the liver of Baikal fishes (Coregonus automnalis, Thymallus articus, Brachymystax lenok and Cottocomphorus greminsky). The administration of 3-methylcholanthrene increases considerably the level of metabolic activity of microsomal fraction and cytochrome P450 content in liver. The data of microsomal fractions of rats and fishes liver electrophoresis have shown that xenobiotic causes the synthesis of similar according to the molecular weight forms of cytochrome P450 in these animals. The induction of microsomal monooxygenase inhibits the lipid peroxidation of microsomal fraction. 相似文献