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Background

In order to increase price competition, government regulations focus on controlling drug costs. Drug costs after patent expiry are an area of particular interest because the substitution of branded medication with generics represents an opportunity for lowering drug costs. However, drug costs may not decrease after patent expiry, because of a lack of price competition and different national pricing systems.

Aim

The aim of this study was to investigate the trends in the use of generics after patent expiry for enalapril, fluoxetine and ranitidine and the subsequent changes, if any, in the costs of these medications.

Methods

A drug-utilisation study was performed using data from a large sample of Dutch pharmacies. Both volumes (measured as defined daily doses [DDD] per 1000 population) as well as drug costs (calculated per DDD) prior to and after patent expiry were calculated. Costs per DDD were compared using trend-line analysis. In addition, the relative market shares of the different trade channels (branded, parallel imported and generic) were compared before and after patent expiry.

Results

The costs per DDD decreased for all three drugs and, as expected, these costs decrease more rapidly after patent expiry. Significant differences in the trend lines were found for enalapril and fluoxetine.

Conclusions

Despite relatively high reimbursement prices for generics in the Netherlands, this example from the Dutch pharmaceutical market demonstrates the benefit of generic substitution for containing pharmaceutical costs, which contrasts with concerns raised by the Dutch government.  相似文献   
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BACKGROUND: Proton pump inhibitors have a prominent role in the management of acid-related diseases. Controlling expenses on proton pump inhibitors would yield great economic benefits for Dutch health care. AIM: To investigate whether clinical differences in proton pump inhibitors exist. METHODS: We searched Medline, EMBASE and the Cochrane Library. We identified papers in English, German, French or Dutch in which two or more proton pump inhibitors were compared under the same clinical conditions in gastro-oesophageal reflux disease, peptic ulcer disease or Helicobacter pylori eradication. The pooled relative risks were calculated using the Mantel-Haenszel method. RESULTS: Two significant differences were found in the proton pump inhibitors compared. In gastro-oesophageal reflux disease, esomeprazole 40 mg was superior to omeprazole 20 mg (relative risk, 1.18; 95% confidence interval, 1.14-1.23). In peptic ulcer disease, pantoprazole 40 mg was superior to omeprazole 20 mg (relative risk, 1.07; 95% confidence interval, 1.02-1.13). In Helicobacter pylori eradication, no significant differences were found. CONCLUSIONS: Both significant differences found were in favour of the highest dose of proton pump inhibitor on a milligram basis. This indicates that the difference may be dose dependent and not proton pump inhibitor specific. Therefore, when prescribing proton pump inhibitors, arguments other than clinical efficacy, such as those related to pharmaco-economics, may be considered.  相似文献   
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目的对吴茱萸Evodia rutaecarpa(Juss.)Benth.的1H-NMR指纹图谱进行解析。方法应用硅胶柱色谱法分离吴茱萸的SCEA和SCEB化学成分,鉴定其结构,并对SCEA和SCEB进行1H-NMR研究,从而实现吴茱萸的1H-NMR指纹图谱的解析。结果吴茱萸SCEA的1H-NMR指纹图谱,主要显示evodiamine、rutaecarpine、dehydroevodiamine 3个化合物的特征共振信号,吴茱萸SCEB的1H-NMR指纹图谱,主要显示dehydroevodiamine的特征共振信号。不同来源的样品其1H-NMR指纹图谱有很好的重现性和特征性。结论吴茱萸的1H-NMR指纹图谱可用于其基源鉴定。  相似文献   
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目的通过训练大鼠急进高原模型从心肌组织形态和酶谱改变,研究训练对心肌损伤的防护。方法于海拔1520m实地环境设实验组(EG)采用中药抗疲I号加入常规饲料中喂养,对照组(CG)常规饲料喂养,EG、CG各40只游泳训练4周后,各选35只3h急进海拔3850m实地静息1.5h,从中各选10只作为静息对照采集标本,EG、CG各20只游泳至力竭后1h、24h采集标本;测定比较各组心肌酶谱指标等,镜下观察比较各组心肌形态变化。结果EG血中心肌酶谱指标1h、24h指标均优于CG1h、24h结果;心肌组织学结构从纵断面看,EG心肌结构清晰,肌丝细密,横纹清楚,核周无空隙;横断面心肌纤维群间隙小,毛细血管平均为10~12个/HPF;CG心肌纤维界限不清晰,肌丝分散,横纹不清楚,横断面心肌纤维群间隙增宽,毛细血管平均为3~5个/HPF,毛细血管腔扩张,红细胞堆积,提示有水肿。结论急进高海拔地区运动后可使心肌纤维缺氧水肿,血中心肌酶谱增高,同时会使心肌营养不良而发生结构改变,对心肌的供氧能力好坏必然决定运动能力强弱,过度训练、改变运动集训环境或强体力劳动均可引起心肌供血能力下降,本研究是通过抗疲I号加入食品干预训练大鼠的,有利于改善心肌营养与供氧状况,并能降低心肌纤维水肿发生。  相似文献   
109.
BACKGROUND: Despite constant improvements in caring for critically ill neonates and infants with congenital cardiac disease, sepsis, bone marrow and solid organ transplantation, acute renal failure (ARF) is an important problem in these children. ARF, severe fluid overload and inborn errors of metabolism are some of the indications for acute dialysis in infants and children. METHODS: The authors had retrospectively evaluated the medical records of Pediatric Intensive Care Unit, Ankara University School of Medicine, Ankara, Turkey patients who had required acute renal replacement therapy between the dates of January 2002 to February 2005. RESULTS: Medical records of 332 patients were reviewed. Acute renal replacement therapy was performed in 21 patients (6.3%; mean age, 9.6 +/- 7.4 years). Dialysis modalities were peritoneal dialysis in 15 patients (71.4%; mean age, 3.9 +/- 5.6 years) and hemodialysis in six patients (28.6%; mean age, 12.1 +/- 3.2 years). A total of 90% of patients had severe systemic disease leading to ARF. A total of 95% of patients had multiple organ dysfunction syndrome. The most common cause of ARF was refractory shock. At the beginning of renal replacement therapy, 10 patients were anuric, nine patients had volume overload, seven patients had decompensated metabolic acidosis and nine patients had hypotension. The average dialysis period was 4.7 +/- 6.4 days. Mortality rate was 66.7%. Eight patients recovered from ARF and chronic renal failure had developed in one patient. CONCLUSION: In the Pediatric Intensive Care Unit, ARF is frequently seen together with multiple organ dysfunction syndrome and the mortality rate is high. Both peritoneal dialysis and hemodialysis are important renal replacement treatment modalities in patients with ARF. The age and hemodynamic status of the patients are important when choosing treatment modality; generally peritoneal dialysis is preferred in infants and toddler, while hemodialysis is preferred in older children.  相似文献   
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Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy.  相似文献   
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