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11.
Medicaid spending is an increasing burden on already stressed state budgets. The states find themselves trapped between these growing costs and mounting pressure to ensure access of the underserved to health care services. States are hopeful that managed care is the answer to meeting the seemingly diametric needs of reducing costs while increasing access. However, evidence of performance measured in cost, access, and quality, and financial viability is inconclusive. Nevertheless, there have been some successes and, clearly, Medicaid managed care has potential. The unanswered question is the extent to which states can meet the diverse challenges of both Medicaid and managed care and tap that potential.  相似文献   
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The lung function response to inhalation of an extract of green coffee was studied in ten healthy subjects who were prescreened for airway hyperresponsiveness to an aerosol of green coffee extract. The effects of this provocation were evaluated at rest and following moderate exercise as well as with and without pretreatment with 80 mg of disodium cromoglycate (DSCG). There was a statistically significant decrement in lung function over time (P less than .001) following coffee provocation both at rest and following exercise. No significant protection against this response was observed with DSCG pretreatment. While the majority of these "healthy" coffee reactors exhibited baseline nonspecific airway hyperresponsiveness to methacholine (PC20 FEV1 less than 25 mg/mL in 7/10), there was no correlation in these ten subjects between baseline responsiveness to methacholine and the degree of lung function decrement following coffee (P greater than .05). Also, no correlation was observed between skin prick and lung function response to coffee extract. We conclude that inhalation of green coffee extract causes significant bronchoconstriction in selected healthy volunteers and that this response is not prevented by pretreatment with DSCG.  相似文献   
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Excessive activity of NADPH oxidase (Nox) is considered to be of importance for the progress of diabetic nephropathy. The aim of the study was to elucidate the effect of melatonin, known for its nephroprotective properties, on Nox activity under diabetic conditions. The experiments were performed on three groups of animals: (i) untreated lean (?/+) Zucker diabetic fatty (ZDF) rats; (ii) untreated obese diabetic (fa/fa) ZDF rats; and (iii) ZDF fa/fa rats treated with melatonin (20 mg/L) in drinking water. Urinary albumin excretion was measured weekly. After 4 wk of the treatment, the following parameters were determined in kidney cortex: Nox activity, expression of subunits of the enzyme, their phosphorylation and subcellular distribution. Histological studies were also performed. Compared to ?/+ controls, ZDF fa/fa rats exhibited increased renal Nox activity, augmented expression of Nox4 and p47phox subunits, elevated level of p47phox phosphorylation, and enlarged phospho‐p47phox and p67phox content in membrane. Melatonin administration to ZDF fa/fa rats resulted in the improvement of renal functions, as manifested by considerable attenuation of albuminuria and some amelioration of structural abnormalities. The treatment turned out to nearly normalize Nox activity, which was accompanied by considerably lowered expression and diminished membrane distribution of regulatory subunits, that is, phospho‐p47phox and p67phox. Thus, it is concluded that: (i) melatonin beneficial action against diabetic nephropathy involves attenuation of the excessive activity of Nox; and (ii) the mechanism of melatonin inhibitory effect on Nox is based on the mitigation of expression and membrane translocation of its regulatory subunits.  相似文献   
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PurposeOur purpose was to assess the effect of a combined intervention – simulation-based training supported by neurofeedback sessions – on radiation technologists’ (RTs’) workload, situation awareness, and performance during routine quality assurance and treatment delivery tasks.Methods and MaterialsAs part of a prospective institutional review board approved study, 32 RTs previously randomized to receive versus not receive simulation-based training focused on patient safety were again randomized to receive versus not receive a 3-week neurofeedback intervention (8 sessions of alpha-theta protocol) focused on stress reduction as well as conscious precision, strong focus, and ability to solve arising problems. Perceived workload was quantified using the NASA Task Load Index. Situation awareness was quantified using the situation awareness rating technique. Performance score was calculated using procedural compliance with time-out components and error detection.ResultsRTs randomized to simulation-based training followed by neurofeedback sessions demonstrated no significant changes in perceived workload or situation awareness scores, but did have better performance compared with other study groups (P < .01).ConclusionsThis finding is encouraging and provides basis for using neurofeedback as means to possibly augment performance improvements gained during simulation-based training.  相似文献   
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Recently, minimally invasive surgery (MIS) robotics enters the phase of autonomous operation. However, because of the high variability of the environment, conducting a fully autonomous surgery is still extremely difficult. This paper presents a share control system, the objective of which is to suggest the optimum path of tool guidance through the use of force on the master manipulator (hereinafter as master), meaning the surgeon's hand. Owing to this type of control, the surgeon has full control over the position of the tool the entire time and is supported by the system to better and faster guide the tool during surgery. The force should be felt by the surgeon but, simultaneously, must not hinder or impact the surgical process. Furthermore, the share control system presented in the paper can be turned on or off at any moment during surgery.  相似文献   
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BACKGROUND/AIMS: To analyze, by means of immunocytochemistry, the cases of fibrolamellar variant of hepatocellular carcinoma (FLC), diagnosed in our Department. METHODOLOGY: The material comprised 4 FLC cases of tumors resected surgically. Besides the routine morphological assessment, we used a panel of immunohistochemical stainings including: hepatocellular cytokeratin, CK7, CK19, Ki67, PCNA, chromogranin A, synaptophysin, NSE, insulin, calcitonin, parathormon, CD34, EBV (LMP), Bcl2, cyclin D1. RESULTS: In 3 out of 4 cases, we observed co-expression of CK7 with hepatocellular CK. In addition, there was positive staining with some endocrine markers in the majority of patients. In one case, we found strong cyclin D1 immunoreactivity which correlated with EBV (LMP) immunoreactivity, in the same patient. The score of PCNA positivity varied between 15 and 90%. In all cases Ki67 was negative. CONCLUSIONS: The incidence of FLC, among all hepatocellular carcinomas diagnosed in our Department was 5.1%. In accordance with other reports, all our FLC cases were young patients without underlying liver disease. We were unable to find a correlation between FLC cellular immunophenotype, and histological and clinical markers of malignancy. In addition, it appears that PCNA is a better marker of cell-proliferation in FLC than Ki67. The significance of EBV infection in FLC requires further study.  相似文献   
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A case of a 51 year old patient with a history of myocardial infarction (MI) and recurrent ventricular tachycardia (VT) is presented. Three months after MI the patient underwent coronary angioplasty and one year later received prophylactic implantable cardioverter-defibrillator (ICD) due to complex ventricular arrhythmias, detected on Holter ECG monitoring, and depressed left ventricular ejection fraction. Later on the patient started to experience palpitations and ICD shocks during physical activity (cycling). Interrogation of the ICD memory showed appropriate shocks due to slow (160 betas/min) VT. The device was reprogrammed and new antitachycardia pacing (ATP) algorithms were enabled, however, it occurred proarrhythmic due to the ATP-induced acceleration of VT rate. Finally, in April 2005 he received 37 appropriate ICD shocks during a few hours. The patient was selected for RF ablation and underwent successful procedure with the use of the electro-anatomical CARTO mapping system.  相似文献   
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