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61.
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   
62.
With inductively coupled plasma-mass spectrometry (ICP-MS), the 18 trace elements Ba, (Be), (Bi), Cd, Co, Cs, Cu, La, Li, Mn, Mo, Pb, Rb, (Sb), (Sn), Sr, (Tl), and Zn were quantified in the digests of 13 formulas based on cow milk, of two formulas based on soy protein, of two milk powders, from which formulas were prepared, of two samples of Austrian cow milk, and in the water, with which the powders were suspended. Concentrations in parentheses were at or below the method detection limits in the formulas. The accuracy and precision of the analytical procedure tested with milk powder reference materials BCR 063 and BCR 150 were satisfactory. The concentrations of trace elements in the powders vary considerably from batch to batch. The ratios of high to low concentrations ranged from 1.1 to 4.8 and were higher for the essential trace elements Co, Cu, Mn, Mo, Sn, and Zn than for nonessential or toxic elements. The contribution of tap water from the water system of the city of Graz, Austria to the concentrations of trace elements in the formulas ranges from 45% for Pb to 0.2% for Rb and is negligible, for instance, for Cd, Cs, La, Mo, and Sn. Preformulas and follow-up formulas are partly supplemented with the essential trace elements Cu, Mn, and Zn and, therefore, concentrations of these trace elements in the formulas vary considerably. However, supplementation of a formula with a particular element must not necessarily result in higher concentrations compared to non-supplemented formulas. Concentrations of the essential elements were in the following ranges for preformulas, follow-up formulas, soy-based formulas (in microg/kg): Co, 8.3-11.2, 4.5-13, 5.0-5.7; Cu, 330-750, 27-730, 440-530; Mn, 33-580, 40-390, 440-530; Mo, 10-32, 9-39, 44-46; Sn, <0.44-3.8, <0.44-1.0, <0.44-5.8; Zn, 3340-11,380, 4120-7100, 5590-6,840. A preformula supplemented with Mn had a 10 times higher manganese concentration than preformulas without supplementation. Concentrations of all trace elements quantified were lower in cow milk than in formulas and do not meet the dietary requirements of infants.  相似文献   
63.
The treatment of cancer patients with conventional chemotherapy is sometimes associated with severe systemic toxicity and only a minimal survival benefit. Because of this, new less toxic and more efficacious treatments have been sought. 8-Chloro-cAMP (8-Cl-cAMP) is one of a new generation of anticancer drugs that act at the level of signal transduction. In preclinical models, 8-Cl-cAMP modulates protein kinase A (PKA) leading to growth inhibition and increased differentiation of cancer cells. 8-Cl-cAMP was given to 16 patients with advanced cancer as an infusion via an indwelling subclavian venous catheter. We showed that 8-Cl-cAMP had a parathyroid hormone-like effect leading to increased synthesis of renal 1,25-dihydroxyvitamin D [up to 14 times the baseline value, median 3.6 times; P = 0.00001 (Student's paired t test)]. This produced the dose-limiting toxicity of reversible hypercalcemia that could not be controlled by the administration of either pamidronate or dexamethasone. The treatment was otherwise well tolerated, and other cAMP-dependent pathways (cortisol and TSH) were not affected, emphasizing the marked differences between organs in their sensitivity to this cAMP analog. Our results have shown that 8-Cl-cAMP is biologically active, and it is feasible that if the hypercalcemia can be controlled, then this drug may have a role as a single agent, or as a short infusion between cycles of chemotherapy.  相似文献   
64.
The performance of a multi-slit Integrated Micro Packed Bed Reactor-Heat Exchanger (IMPBRHE) for methanol synthesis from synthesis gas over Cu/ZnO/support commercial catalyst was experimentally investigated from a reaction engineering perspective. Through establishment of a systematic comparison strategy, performance comparison with a laboratory scale tubular Fixed-Bed Reactor (FBR) with three different dilution ratios was made to evaluate the IMPBRHE. The productivity, thermal behavior, activity of body materials, pressure drop and residence time distribution (RTD) of the two reactor types were investigated. The IMPBRHE outperformed the undiluted FBR and gave CO conversions comparable to the diluted FBRs. The main difference is ascribed to superior heat exchange properties of the IMPBRHE, which can improve reactor performance for an exothermic reaction such as methanol synthesis. The results reveal advantages of the IMPBRHE for robust scale up.  相似文献   
65.
6月6日,中央全面深化改革领导小组第三次会议召开,会议审议通过了“关于设立知识产权法院的方案》等方案。  相似文献   
66.
B. Kuchta  L. Firlej  P. Pfeifer 《Carbon》2010,48(1):223-231
Theoretical limits of the hydrogen adsorption in carbon nanospaces are modeled using Monte Carlo simulations. A detailed analysis of storage capacity of slit pores has been performed as a function of the pore size, gas pressure (up to 100 bars) and temperature of adsorption (77 and 298 K). The H2-slit wall interaction has been modeled assuming energies of adsorption ranging from 4.5 kJ/mol (pure graphene surface) to 15 kJ/mol (hypothetical chemically modified graphene). The quantum nature of H2 has been incorporated in the calculations using the Feynman-Hibbs approach. It has been shown that in a hypothetical chemically modified porous carbon, with energy of adsorption of 15 kJ/mol or higher and pore size between 0.8 and 1.1 nm, the gravimetric and volumetric storage capacity can achieve targets required for practical applications. The relation between the energy of adsorption and the effective delivery has been discussed.  相似文献   
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In groupware tools, the activation of a function may affect other users who might have conflicting interests. We developed technical mechanisms to support users in resolving them. Contrary to current implementations of groupware tools, these mechanisms strengthen the position of the users who are affected by the activation of said functions. Supporting the visibility of a function's activation, and providing a channel for communication or means to intervene against the function's activation are approaches which constitute a framework to implement these mechanisms. We conclude with showing implementation examples of the framework and their evaluation in the POLITeam project.  相似文献   
70.
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