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991.
HMOs, PPOs, and other managed care "middlemen" control the means by which most physicians do business with employers. As physicians face dwindling reimbursements, greater practice restrictions, and increased pressure to sign adversarial middleman contracts, interest in direct contracting has grown. This article introduces direct contracting as an important alternative to commercial managed care agreements; cites the key advantages and process of direct contracting; and offers practical recommendations for helping physician practices successfully negotiate direct physician/employer agreements.  相似文献   
992.
PURPOSE: To determine how glaucoma and glaucoma suspect patients' rating of their vision correlates with Esterman binocular visual field testing and other visual function tests. METHODS: One hundred ninety-one glaucoma patients and 46 glaucoma suspect patients underwent binocular visual field testing and evaluated their vision using the linear rating scale and time-tradeoff utility tests, the National Eye Institute Visual Functional Questionnaire (NEI VFQ-25), and the Short Form 36 (SF-36) quality-of-life instruments. RESULTS: The mean Esterman score was 88.2 +/- 17.4 for the glaucoma subjects and 95.2 + 6.9 for glaucoma suspect subjects (maximum score 100). On a scale from 0 (blind) to 100 (ideal), the mean rating of vision for glaucoma patients and glaucoma suspect patients was 74.8 +/- 17.3 and 78.9 +/- 18.5, respectively. The Esterman test correlated moderately with the overall NEI VFQ-25 score (partial correlation coefficient (PCC) = 0.32, P = 0.001), but only weakly with the linear rating scale (PCC = 0.17, P = 0.02), and the time-tradeoff (PCC = 0.14, P = 0.06). CONCLUSION: Utility values that glaucoma and glaucoma suspect patients assign to their vision do not correlate well with Esterman results. A challenge for the future is the design of clinical tests of vision that better correlate with patient perceptions.  相似文献   
993.
Clinical applications of capsular tension rings in cataract surgery   总被引:1,自引:0,他引:1  
BACKGROUND: Although the open capsular tension ring was designed to manage zonular dialysis during cataract surgery, it also lowers the incidence of capsule contraction, stabilizes the capsular bag, and enhances IOL centration. With appendages, it provides a partial solution for those eyes with colobomata and aniridia. MATERIALS AND TECHNIQUES: Subsequent modifications to the capsular tension ring include the Cionni ring, capsular edge ring, coloboma ring, and aniridia ring. A square-edge design may inhibit posterior capsule opacification, and the aniridia and coloboma rings with appendages create an artificial it is in traumatic or congenital colobomata. RESULTS: Designs, functions, indications, and results of different types of capsular tension rings are reviewed, as well as applications in pediatric cases, and considerations for their routine use in adult cataract surgery. CONCLUSIONS: The potential benefits of capsular edge ring implantation in pediatric cataract surgery cases are explored.  相似文献   
994.
Niuhuang is a commonly used Chinese traditional medicine with immunoregulatory and anti-inflammatory properties. Deoxycholic acid (DCA) is a major active constituent of Niuhuang. The reaction of human leukocytes to chemoattractants is an important part of the host immune response and also plays a crucial role in the development of inflammation. We, therefore, investigated the in vitro effects of DCA on human monocyte and neutrophil responses to classic chemoattractants [fMet-Leu-Phe (fMLP), complement fraction 5a (C5a)], CC chemokine [monocyte chemoattractant protein-1 (MCP-1/CCL2)], and/or CXC chemokines [stromal cell-derived factor-1 (SDF-1alpha/CXCL12), interleukin-8 (IL-8/CXCL8)]. The results showed that DCA significantly inhibited fMLP-induced monocyte and neutrophil chemotaxis and calcium mobilization, and also blocked the binding of [3H]fMLP and anti-formyl peptide receptor (FPR) monoclonal antibodies (mAb) to the cells. The inhibitory effects of DCA on calcium mobilization and anti-FPR-mAb binding to the receptor could be abrogated by washing DCA out of the cell suspension, suggesting that DCA blocked fMLP receptors via a steric hindrance mechanism, not via receptor internalization. DCA had no significant inhibitory effects on MCP-1-, SDF-1alpha-, or C5a-induced monocyte function, or C5a- or IL-8-induced neutrophil function. Taken together, our experimental results suggest that blockade of fMLP receptors may contribute to the anti-inflammatory effects of traditional medicine containing DCA.  相似文献   
995.
Axelrad JC  Howard CV  McLean WG 《Toxicology》2002,173(3):259-268
Organophosphate (OP) pesticides are often used in combination with one another and with the components of formulations. Evidence already exists for interactions in the neurotoxic effects of OPs through interference with metabolism, but there is also potential for interactions related directly to cell damage. The purpose of this work was to investigate this possibility for OPs and the components of one of their common formulations in vitro. NB2a neuroblastoma cells were induced to differentiate in the presence of the OPs diazinon and chlorpyrifos, in combination with a commercial formulation (identified as Commercial Formulation 1) of the compounds and, independently, the components of that formulation. The compounds were tested in pairs in various proportions and the resulting inhibition of neurite outgrowth was measured by light microscopy and quantitative image analysis. Interactions were determined in terms of enhanced or reduced effects of the paired compounds in comparison with the expected additive effects estimated from the effects of each compound on its own. Synergism was detected between combinations of: 10 microM chlorpyrifos and 500 nM pyrethrum; chlorpyrifos and one of the solvents (regular spirit) found in Commercial Formulation 1. All other combinations of OPs and products were additive in their neurotoxicity. The data suggest that exposure to multiple OP-containing pesticide formulations may lead to synergistic neurotoxicity by a direct mechanism at the cellular level.  相似文献   
996.
997.
998.
We report a case of Escherichia coli O157:H7, which was acquired by eating wild White-Tailed deer (Odocoileus virginianus). DNA fingerprint analysis verified venison as the source of infection. This pediatric case emphasizes the need for dissemination of information to hunters regarding the safe handling and processing of venison.  相似文献   
999.
Widespread consumer suspicion about the quality of managed care indicates that marketers still have work to do Research shows that women identify personal relationships with physicians, medical expertise, speed of access, and comprehensiveness of service as important signs of quality when selecting a managed care plan for their families. Based on existing research findings and new focus group data, this article provides guidelines for promoting an association of quality with managed care, particularly among women.  相似文献   
1000.
The diagnosis of pericardial constriction is challenging and elusive. It is a postinflammatory condition that occurs when a thickened, fibrotic, scarred and sometimes calcified pericardium firmly encases the cardiac chambers and restricts filling of the heart, causing venous overload and diminished cardiac output. This review includes the diagnosis and management of this condition.  相似文献   
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