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101.
The Physicians' Working Group for Single-Payer National Health Insurance*

JAMA. 2003;290:798-805.

The United States spends more than twice as much on health care as the average of other developed nations, all of which boast universal coverage. Yet more than 41 million Americans have no health insurance. Many more are underinsured. Confronted by the rising costs and capabilities of modern medicine, other nations have chosen national health insurance (NHI). The United States alone treats health care as a commodity distributed according to the ability to pay, rather than as a social service to be distributed according to medical need. In this market-driven system, insurers and providers compete not so much by increasing quality or lowering costs, but by avoiding unprofitable patients and shifting costs back to patients or to other payers. This creates the paradox of a health care system based on avoiding the sick. It generates huge administrative costs that, along with profits, divert resources from clinical care to the demands of business. In addition, burgeoning satellite businesses, such as consulting firms and marketing companies, consume an increasing fraction of the health care dollar. We endorse a fundamental change in US health care—the creation of an NHI program. Such a program, which in essence would be an expanded and improved version of traditional Medicare, would cover every American for all necessary medical care. An NHI program would save at least $200 billion annually (more than enough to cover all of the uninsured) by eliminating the high overhead and profits of the private, investor-owned insurance industry and reducing spending for marketing and other satellite services. Physicians and hospitals would be freed from the concomitant burdens and expenses of paperwork created by having to deal with multiple insurers with different rules, often designed to avoid payment. National health insurance would make it possible to set and enforce overall spending limits for the health care system, slowing cost growth over the long run. An NHI program is the only affordable option for universal, comprehensive coverage.

  相似文献   

102.
103.
Blood Group-Active Surface Molecules of the Human Red Blood Cell   总被引:8,自引:0,他引:8  
The surface of the human red blood cell is dominated by a small number of abundant blood group active proteins. The major proteins are the anion transport protein (band 3) which has AB(H) activity, and Glycophorin A which has MN activity. Band 3 and Glycophorin A are of equal abundance in the normal red cell membrane (approximately 10(6) copies of each) and the two proteins may associate together as a complex. The glucose transporter (band 4.5) had AB(H) activity and there are about 5 x 10(5) copies/red cell. Several polypeptides associate together to form the Rh complex. The major components of this complex (abundance 1-2 x 10(5) copies/red cell) are polypeptides of Mr 30,000, polypeptides of Mr 45,000-100,000 and Glycophorin B. The antigens of the Rh blood group system appear to be associated with the polypeptides of Mr 30,000 and those of Mr 45,000-100,000 (the latter also express AB(H) activity). Glycophorin B expresses the blood group 'N' antigen and the Ss antigens. Glycophorins C and D carry the Gerbich antigens and, together, these polypeptides comprise approximately 10(5) copies/red cell. The complete protein sequence of all the above-mentioned proteins is known, except for the Mr 30,000 and Mr 45,000-100,000 polypeptides of the Rh complex for which only partial sequences are available, and Glycophorin D, the sequence of which can be inferred from that of Glycophorin C. Several of the minor blood group active proteins at the red cell surface (abundance less than 1.2 x 10(4)/red cell) have been the subject of recent studies. The polypeptide expressing Cromer-related blood group antigens has been identified as decay-accelerating factor and that carrying the Ina/Inb antigens as CD44. The protein sequence of both of these proteins has been deduced form nucleotide sequencing. The polypeptides expressing Kell antigens, Lutheran antigens, Fy antigens, and LW antigens have also been identified and partially characterised.  相似文献   
104.
The in-vitro activity of ten antimicrobial agents was evaluated for 28 clinical isolates of Bacteroides ureolyticus, an obligate anaerobe associated with non-gonococcal urethritis. The isolates were characterized by plasmid DNA profile and PAGE protein pattern. All isolates were inhibited at concentrations equal to or lower than the recommended breakpoint concentration for ampicillin (16 mg/l), metronidazole (16 mg/l) and erythromycin (4 mg/l). Twenty-seven isolates were inhibited by less than or equal to 2 mg/l of ciprofloxacin, pefloxacin and ofloxacin. Four isolates were tetracycline-resistant requiring 2-64 mg/l of tetracycline, minocycline or doxycycline for inhibition. In two tetracycline-resistant isolates tetM was demonstrated by dot-blot and Southern hybridizations. These two isolates did not contain a plasmid and had a PAGE protein pattern type III. These data confirm the spread of the tetM determinant in various bacteria of the genital tract.  相似文献   
105.
A small proteoglycan that contains only a single dermatan sulfate chain is the main proteoglycan synthesized by skin fibroblasts. Fibroblasts from a patient with progeroidal appearance and symptoms of the Ehlers-Danlos syndrome have a reduced ability of converting the core protein of this proteoglycan into a mature glycosaminoglycan chain-bearing species. This abnormality is the consequence of a deficiency in galactosyltransferase I (xylosylprotein 4-beta-galactosyltransferase; EC 2.4.1.133), which catalyzes the second glycosyl transfer reaction in the assembly of the dermatan sulfate chain. The glycosaminoglycan-free core protein secreted by the patient's fibroblasts bears an unsubstituted xylose residue. The mutant enzyme is abnormally thermolabile. Preincubation of fibroblasts at 41 degrees C leads to a further reduction in the production of mature proteoglycan and affects the capacity for glycosaminoglycan synthesis on p-nitrophenyl beta-D-xyloside more strongly in the mutant than in control cells.  相似文献   
106.
Monoclonal antibodies against glycophorins and other glycoproteins   总被引:1,自引:0,他引:1  
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107.
Consider a single agent capable of diagnosing cancer, treating it simultaneously and monitoring response to treatment. Particles of this agent would seek cancer cells accurately and destroy them without harming normal surrounding cells. Science fiction or reality? Nanotechnology and nanomedicine are rapidly growing fields that encompass the creation of materials and devices at atomic, molecular and supramolecular level, for potential clinical use. Advances in nanotechnology are bringing us closer to the development of dual and multi-functional nanoparticles that are challenging the traditional distinction between diagnostic and treatment agents. Examples include contrast agents capable of delivering targeted drugs to specific epithelial receptors. This opens the way for targeted chemotherapy which could minimise systemic side-effects, avoid damage to benign tissues and also reduce the therapeutic treatment dose of a drug required. Most of the current research is still at the pre-clinical stage, with very few instances of bench to bedside research. In order to encourage more translational research, a fundamental change is required to consider the current clinical challenges and then look at ways in which nanotechnology can address these.  相似文献   
108.
109.
Cone snails are carnivorous marine gastropods that have evolved potent venoms to capture their prey. These venoms comprise a rich and diverse cocktail of peptide toxins, or conopeptides, whose high diversity has arisen from an efficient hypermutation mechanism, combined with a high frequency of post-translational modifications. Conopeptides bind with high specificity to distinct membrane receptors, ion channels, and transporters of the central and muscular nervous system. As well as serving their natural function in prey capture, conopeptides have been utilized as versatile tools in neuroscience and have proven valuable as drug leads that target the nervous system in humans. This paper examines current knowledge on conopeptide sequences based on an analysis of gene and peptide sequences in ConoServer (http://www.conoserver.org), a specialized database of conopeptide sequences and three-dimensional structures. We describe updates to the content and organization of ConoServer and discuss correlations between gene superfamilies, cysteine frameworks, pharmacological families targeted by conopeptides, and the phylogeny, habitat, and diet of cone snails. The study identifies gaps in current knowledge of conopeptides and points to potential directions for future research.  相似文献   
110.
The combined activity of fosfomycin with rifampin, pefloxacin and imipenem was investigated, by the checkerboard method performed in liquid medium, against 50 clinical isolates of staphylococci (25 Staphylococcus aureus and 25 coagulase-negative staphylococci). The combination of fosfomycin plus rifampin had an additive bacteriostatic effect and an antagonistic bactericidal effect. Fosfomycin combined with pefloxacin was found to be additive or moderately synergistic. Fosfomycin in combination with imipenem was generally highly synergistic, especially against meticillin-resistant strains; however the bactericidal effect was occasionally antagonistic.  相似文献   
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