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91.
Health systems are consistently inequitable, providing more and higher quality services to the well-off, who need them less, than to the poor, who are unable to obtain them. In the absence of a concerted effort to ensure that health systems reach disadvantaged groups more effectively, such inequities are likely to continue. Yet this situation need not be accepted as inevitable, for there are many promising measures that might be pursued: establishment of goals for improved coverage in the poor, rather than in entire populations, and use of those goals to direct planning toward the needs of the disadvantaged; use of one or more of the several techniques that seem to have been effective in at least some of the settings where they have been tried; and empowerment of poor clients to have a more central role in health system design and operation. 相似文献
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Soleimani A Salarifar M Kasaian SE Sadeghian S Nejatian M Abbasi A 《Asian cardiovascular & thoracic annals》2008,16(3):202-207
To evaluate the effects of a cardiac rehabilitation program on heart rate recovery after percutaneous transluminal coronary angioplasty, a historical cohort study was performed on 436 patients of whom 285 were grouped on completion of 5, 10, or 24 training sessions. All 3 groups showed significant improvements in heart rate recovery, peak heart rate during treadmill testing, and end-training heart rate, from baseline to follow-up. Heart rate recovery on follow-up correlated significantly with the number of completed exercise sessions. The number of sessions, baseline ejection fraction, and age were independent predictors of mean post-training heart rate recovery. The cardiac rehabilitation program had a significant effect on peak heart rate and heart rate recovery, regardless of the underlying characteristics of the patients. 相似文献
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Zahedpasha Y Ahmadpour-Kacho M Hajiahmadi M Naderi S Kamali AA 《The Southeast Asian journal of tropical medicine and public health》2008,39(3):557-561
Glucose-6-phosphate dehydrogenase (G6PD) deficiency may cause severe hyperbilirubinemia with bilirubin encephalopathy unless intervention is initiated. The aim of this study was to assess the efficacy of clofibrate in full term G6PD deficient neonates with jaundice. A randomized clinical trial study was performed in two groups of full-term G6PD deficient jaundiced neonates (clofibrate treated group, n = 21; control group, n = 19). Infants in the clofibrate group received a single oral dose of 100 mg/kg clofibrate, whereas control group received nothing. Both groups were treated with phototherapy. Serum total and direct bilirubin levels were measured at the onset of treatments, 16, 24 and 48 hours later. On enrollment, the mean total serum bilirubin (TSB) level in the clofibrate treated group was 18.40 +/- 2.41 and in the control group was 17.49 +/- 1.03 (p = 0.401). At 16, 24 and 48 hours of treatment, the mean TSB in the clofibrate group were 15.2 +/- 1.9, 12.6 +/- 2.4, and 10.1 +/- 2.4 and in the control group were 16.5 +/- 1.2, 13.3 +/- 2.2 and 11.4 +/- 2.4, respectively (p = 0.047). At 48 hours, 7 (33%) cases in the clofibrate group and one (5%) case in the control group were discharged with a TSB < 10 mg/dl (p = 0.031). No side effects were observed on serial examinations during hospitalization, or on the 1st and 7th days after discharge. The results show that clofibrate induces a faster decline in serum total bilirubin level, a shorter duration of phototherapy, and hospitalization with no side effects in full-term G6PD deficient neonates with jaundice. 相似文献
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Comparative assessment of in vitro and in vivo toxicity of azinphos methyl and its commercial formulation
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The toxic effects of Gusathion (GUS), which is a commercial organophosphate (OP) pesticide, and also its active ingredient, azinphos methyl (AzM), are evaluated comparatively with in vitro and in vivo studies. Initially, the 96‐h LC50 values of AzM and GUS were estimated for two different life stages of Xenopus laevis, embryos, and tadpoles. The actual AzM concentrations in exposure media were monitored by high‐performance liquid chromatography. Also, the sub‐lethal effects of these compounds to tadpoles were determined 24 h later at exposure concentrations of 0.1 and 1 mg/L using selected biomarker enzymes such as acetylcholinesterase (AChE), carboxylesterase (CaE), glutathione S‐transferase (GST), glutathione reductase, lactate dehydrogenase, and aspartate aminotrasferase. Differences in AChE inhibition capacities of AzM and GUS were evaluated under in vitro conditions between frogs and fish in the second part of this study. The AChE activities in a pure electrical eel AChE solution and in brain homogenates of adult Cyprinus carpio, Pelophylax ridibundus, and X. laevis were assayed after in vitro exposure to 0.05, 0.5, 5, and 50 mg/L concentrations of AzM and GUS. According to in vivo studies AChE, CaE and GST are important biomarkers of the effect of OP exposure while CaE may be more effective in short‐term, low‐concentration exposures. The results of in vitro studies showed that amphibian brain AChEs were relatively more resistant to OP exposure than fish AChEs. The resistance may be the cause of the lower toxicity/lethality of OP compounds to amphibians than to fish. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1091–1101, 2015. 相似文献
100.
Hormetic effects of noncoplanar PCB exposed to human lung fibroblast cells (HELF) and possible role of oxidative stress
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Muhammad Zaffar Hashmi Kiran Yasmin Khan Jinxing Hu Naveedullah Xiaomei Su Ghulam Abbas Chunna Yu Chaofeng Shen 《Environmental toxicology》2015,30(12):1385-1392
Hormesis, a biphasic dose–response phenomenon, which is characterized by stimulation of an end point at a low‐dose and inhibition at a high‐dose. In the present study we used human lungs fibroblast (HELF) cells as a test model to evaluate the role of oxidative stress (OS) in hormetic effects of non coplanar PCB 101. Results from 3‐(4,5‐dime‐thylthiazol‐2‐yl)‐2,5‐diphenyltetrazo‐lium bromide (MTT) assay indicated that PCB101 at lower concentrations (10?5 to 10?1 μg mL?1) stimulated HELF cell proliferation and inhibited at high concentrations (1, 5, 10, and 20 μg mL?1) in a dose‐ and time‐dependent manner. Reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) (except 48 h) showed a significant increase at higher concentrations of PCB 101 than those at the lower concentrations with the passage of time. Antioxidant enzymes such as glutathione peroxidase (GSH‐Px) exhibited decreasing trends in dose and time dependent manner. Lipid peroxidation assay resulted in a significant increase (P < 0.05) of MDA level in PCB 101‐treated HELF cells compared with controls, suggesting that OS plays a key role in PCB 101‐induced toxicity. Comet assay indicated a significant increase in genotoxicity at higher concentrations of PCB 101 exposure compared to lower concentrations. Overall, we found that HELF cell proliferation was higher at low ROS level and vice versa, which revealed activation of cell signaling‐mediated hormetic mechanisms. The results suggested that PCB 101 has hormetic effects to HELF cells and these were associated with oxidative stress. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1385–1392, 2015. 相似文献