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31.
How health care providers are paid affects how medicine is practiced. It is thus important to assess provider payment models not only from the economic perspective but also from the ethical perspective. China recently started to reform the provider payment model in the health care system from fee‐for‐service to case‐based payment. This paper aims to examine this transition from an ethical perspective. We collected empirical studies on the impact of case‐based payment in the Chinese health care system and applied a systematic ethical matrix that integrates clinical ethics and public health ethics to analyze the empirical findings. We identified eleven prominent ethical issues related to case‐based payment. Some ethical problems of case‐based payment in China are comparable to ethical problems of managed care and diagnosis related groups in high‐income countries. However, in this paper we discuss in greater detail four specific ethical issues in the Chinese context: professionalism, the patient‐physician relationship, access to care and patient autonomy. Based on the analysis, we cautiously infer that case‐based payment is currently more ethically acceptable than fee‐for‐service in the context of China, mainly because it seems to lower financial barriers to access care. Nonetheless, it will be difficult to justify the implementation of case‐based payment if no additional measures are taken to monitor and minimize its existing negative ethical implications. 相似文献
32.
Case notes of 1113 consecutive new patients referred to a consultant ophthalmologist at a district general hospital were reviewed to determine the source and efficacy of referrals and the current screening practices of general practitioners and ophthalmic opticians. General practitioners initiated referral in 546 cases (49%) and ophthalmic opticians referral in 439 (39%). Visual loss or visual disturbance was the most important single reason for referral (345 cases; 31%), followed by suspected glaucoma (145 cases; 13%), abnormalities of binocular vision (140; 12.5%), disorders of eyelids or ocular adnexa (127; 11%), and red eye (86; 8%). General practitioners referred many more patients with disorders of the eyelids and adnexa and ophthalmic opticians many more patients with suspected glaucoma. Ophthalmic opticians were far more likely than general practitioners to refer patients with suspected glaucoma correctly. A total of 180 patients (16%) were referred from ocular screening, in 149 cases by ophthalmic opticians and in 10 by general practitioners. Seventy patients had glaucoma or incomplete features of glaucoma, all of them referred by ophthalmic opticians. Of eight diabetic patients referred by ophthalmic opticians, three had asymptomatic disease and in two diabetes was diagnosed as a result of ocular screening. No patient was referred for asymptomatic diabetic retinopathy from screening by general practitioners. Ophthalmic opticians were more likely than general practitioners to diagnose retinopathy requiring photocoagulation. Use of a community based service to screen for glaucoma could save unnecessary consultant outpatient appointments. A similar service could facilitate detection of diabetic retinopathy at a stage when treatment is most effective. 相似文献
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von Boehmer L Keller L Mortezavi A Provenzano M Sais G Hermanns T Sulser T Jungbluth AA Old LJ Kristiansen G van den Broek M Moch H Knuth A Wild PJ 《PloS one》2011,6(7):e21366
The cancer-testis (CT) family of antigens is expressed in a variety of malignant neoplasms. In most cases, no CT antigen is found in normal tissues, except in testis, making them ideal targets for cancer immunotherapy. A comprehensive analysis of CT antigen expression has not yet been reported in prostate cancer. MAGE-C2/CT-10 is a novel CT antigen. The objective of this study was to analyze extent and prognostic significance of MAGE-C2/CT10 protein expression in prostate cancer. 348 prostate carcinomas from consecutive radical prostatectomies, 29 castration-refractory prostate cancer, 46 metastases, and 45 benign hyperplasias were immunohistochemically analyzed for MAGE-C2/CT10 expression using tissue microarrays. Nuclear MAGE-C2/CT10 expression was identified in only 3.3% primary prostate carcinomas. MAGE-C2/CT10 protein expression was significantly more frequent in metastatic (16.3% positivity) and castration-resistant prostate cancer (17% positivity; p<0.001). Nuclear MAGE-C2/CT10 expression was identified as predictor of biochemical recurrence after radical prostatectomy (p = 0.015), which was independent of preoperative PSA, Gleason score, tumor stage, and surgical margin status in multivariate analysis (p<0.05). MAGE-C2/CT10 expression in prostate cancer correlates with the degree of malignancy and indicates a higher risk for biochemical recurrence after radical prostatectomy. Further, the results suggest MAGE-C2/CT10 as a potential target for adjuvant and palliative immunotherapy in patients with prostate cancer. 相似文献
35.
Modification of near active site residues in organophosphorus hydrolase reduces metal stoichiometry and alters substrate specificity 总被引:1,自引:0,他引:1
Organophosphorus hydrolase (OPH, EC 8.1.3.1) is a dimeric, bacterial enzyme that detoxifies many organophosphorus neurotoxins by hydrolyzing a variety of phosphonate bonds. The histidinyl residues at amino acid positions 254 and 257 are located near the bimetallic active site present in each monomer. It has been proposed that these residues influence catalysis by interacting with active site residues and the substrate in the binding pocket. We replaced the histidine at position 254 with arginine (H254R) and the one at position 257 with leucine (H257L) independently to form the single-site-modified enzymes. The double modification was also constructed to incorporate both changes (H254R/H257L). Although native OPH has two metals at each active site (four per dimer), all three of these altered enzymes possessed only two metals per dimer while retaining considerable enzymatic activity for the preferred phosphotriester (P-O bond) substrate, paraoxon (5-100% kcat). The three altered enzymes achieved a 2-30-fold increase in substrate specificity (kcat/Km) for demeton S (P-S bond), an analogue for the chemical warfare agent VX. In contrast, the substrate specificity for diisopropyl fluorophosphonate (P-F bond) was substantially decreased for each of these enzymes. In addition, H257L and H254R/H257L showed an 11- and 18-fold increase, respectively, in specificity for NPPMP, the analogue for the chemical warfare agent soman. These results demonstrate the ability to significantly enhance the specificity of OPH for various substrates by site-specific modifications, and it is suggested that changes in metal requirements may affect these improved catalytic characteristics by enhancing structural flexibility and improving access of larger substrates to the active site, while simultaneously decreasing the catalytic efficiency for smaller substrates. 相似文献
36.
HIV-1 candidate vaccines expressing an artificial polyprotein comprising Gag, Pol and Nef (GPN) and a secreted envelope protein (Env) were shown in recent Phase I/II clinical trials to induce high levels of polyfunctional T cell responses; however, Env-specific responses clearly exceeded those against Gag. Here, we assess the impact of the GPN immunogen design and variations in the formulation and vaccination regimen of a combined GPN/Env DNA vaccine on the T cell responses against the various HIV proteins. Subtle modifications were introduced into the GPN gene to increase Gag expression, modify the expression ratio of Gag to PolNef and support budding of virus-like particles. I.m. administration of the various DNA constructs into BALB/c mice resulted in an up to 10-fold increase in Gag- and Pol-specific IFNγ(+) CD8(+) T cells compared to GPN. Co-administering Env with Gag or GPN derivatives largely abrogated Gag-specific responses. Alterations in the molar ratio of the DNA vaccines and spatially or temporally separated administration induced more balanced T cell responses. Whereas forced co-expression of Gag and Env from one plasmid induced predominantly Env-specific T cells responses, deletion of the only H-2(d) T cell epitope in Env allowed increased levels of Gag-specific T cells, suggesting competition at an epitope level. Our data demonstrate that the biochemical properties of an artificial polyprotein clearly influence the levels of antigen-specific T cells, and variations in formulation and schedule can overcome competition for the induction of these responses. These results are guiding the design of ongoing pre-clinical and clinical trials. 相似文献
37.
Demirkan A van Duijn CM Ugocsai P Isaacs A Pramstaller PP Liebisch G Wilson JF Johansson Å Rudan I Aulchenko YS Kirichenko AV Janssens AC Jansen RC Gnewuch C Domingues FS Pattaro C Wild SH Jonasson I Polasek O Zorkoltseva IV Hofman A Karssen LC Struchalin M Floyd J Igl W Biloglav Z Broer L Pfeufer A Pichler I Campbell S Zaboli G Kolcic I Rivadeneira F Huffman J Hastie ND Uitterlinden A Franke L Franklin CS Vitart V;DIAGRAM Consortium Nelson CP Preuss M;CARDIoGRAM Consortium Bis JC O'Donnell CJ 《PLoS genetics》2012,8(2):e1002490
Phospho- and sphingolipids are crucial cellular and intracellular compounds. These lipids are required for active transport, a number of enzymatic processes, membrane formation, and cell signalling. Disruption of their metabolism leads to several diseases, with diverse neurological, psychiatric, and metabolic consequences. A large number of phospholipid and sphingolipid species can be detected and measured in human plasma. We conducted a meta-analysis of five European family-based genome-wide association studies (N = 4034) on plasma levels of 24 sphingomyelins (SPM), 9 ceramides (CER), 57 phosphatidylcholines (PC), 20 lysophosphatidylcholines (LPC), 27 phosphatidylethanolamines (PE), and 16 PE-based plasmalogens (PLPE), as well as their proportions in each major class. This effort yielded 25 genome-wide significant loci for phospholipids (smallest P-value = 9.88×10−204) and 10 loci for sphingolipids (smallest P-value = 3.10×10−57). After a correction for multiple comparisons (P-value<2.2×10−9), we observed four novel loci significantly associated with phospholipids (PAQR9, AGPAT1, PKD2L1, PDXDC1) and two with sphingolipids (PLD2 and APOE) explaining up to 3.1% of the variance. Further analysis of the top findings with respect to within class molar proportions uncovered three additional loci for phospholipids (PNLIPRP2, PCDH20, and ABDH3) suggesting their involvement in either fatty acid elongation/saturation processes or fatty acid specific turnover mechanisms. Among those, 14 loci (KCNH7, AGPAT1, PNLIPRP2, SYT9, FADS1-2-3, DLG2, APOA1, ELOVL2, CDK17, LIPC, PDXDC1, PLD2, LASS4, and APOE) mapped into the glycerophospholipid and 12 loci (ILKAP, ITGA9, AGPAT1, FADS1-2-3, APOA1, PCDH20, LIPC, PDXDC1, SGPP1, APOE, LASS4, and PLD2) to the sphingolipid pathways. In large meta-analyses, associations between FADS1-2-3 and carotid intima media thickness, AGPAT1 and type 2 diabetes, and APOA1 and coronary artery disease were observed. In conclusion, our study identified nine novel phospho- and sphingolipid loci, substantially increasing our knowledge of the genetic basis for these traits. 相似文献
38.
We report on a new population of gorillas discovered in November 2002 in the Ebo Forest, Littoral Province, Cameroon. We observed A group of q7 gorillas directly for 83 min, and they were in auditory range for 155 min. Further evidence of gorilla presence included 8 nest groups totaling 38 nests, distinctive feeding signs accompanied by footprints, and a gorilla cranium collected from the nearby village of Iboti. This newly discovered gorilla population is geographically intermediate between the 2 extant populations of western gorillas: Gorilla gorilla gorilla, the most populous gorilla subspecies living in Gabon, Equatorial Guinea, Congo-Brazzaville, Central African Republic and Cameroon to the south of the Sanaga River, and G. g. diehli or the Cross River gorilla, a small population of ca. 250 individuals on the Cameroon-Nigeria border. It is not possible to assign the new gorilla population to either subspecies on the basis of measurements of the single male cranium. Genetic analyses of freshly shed hairs, collected from gorilla nests, may help to resolve the taxonomic status of the Ebo gorillas. 相似文献
39.
40.
Dissimilar plasmids isolated from Pseudomonas diminuta MG and a Flavobacterium sp. (ATCC 27551) contain identical opd genes 总被引:2,自引:0,他引:2
L L Harper C S McDaniel C E Miller J R Wild 《Applied and environmental microbiology》1988,54(10):2586-2589
The opd (organophosphate-degrading) gene derived from a 43-kilobase-pair plasmid (pSM55) of a Flavobacterium sp. (ATCC 27551) has a sequence identical to that of the plasmid-borne gene of Pseudomonas diminuta. Hybridization studies with DNA fragments obtained by restriction endonuclease digestion of plasmid DNAs demonstrated that the identical opd sequences were encoded on dissimilar plasmids from the two sources. 相似文献