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81.
Statutory reimbursement agencies as well as private insurers throughout member states of the Organization for Economic Cooperation and Development (OECD) reimburse the cost of medicines on the basis of criteria that include robust clinical evidence, budget impact analysis, and incremental cost effectiveness. The Centers for Medicare and Medicaid Services (CMS) in the US are no exception to this rule and are, in principle, seeking to maximize benefit for their Medicare enrollees, whilst ensuring reasonable drug outlays for the small number of drugs that they reimburse. This paper provides a retrospective analysis of the way two functionally equivalent drugs are treated for reimbursement purposes by the CMS; the period under consideration was 2001–3. The two drugs, epoetin-α and darbepoetin-α, are used for the treatment of anemia in renal failure and in patients receiving chemotherapy. By reviewing the publicly available pharmacological and clinical data of epoetin-α and darbepoetin-α, the paper confirms the two drugs’ functional equivalence, despite their structural differences. The implications of dose conversion ratios and costs to Medicare are subsequently explored. It is argued that the issue of dose equivalence between epoetin-α and darbepoetin-α has significant implications for patients, practitioners, and payors. A payor’s perspective is adopted in this respect, whereby clinical evidence and pricing data are used simultaneously. Based on the clinical evidence, a dose conversion ratio for epoetin-α:darbepoetin-α is established, which achieves a comparable clinical effect for the two drugs and this is set to be <254IU:1μg. The incremental costs to Medicare are calculated subsequently. The Average Wholesale Price and the Outpatient Prospective Payment System rule that Medicare uses to reimburse providers are used and suggest that treatment of cancer patients with chemotherapy-related anemia with epoetin-α would save Medicare an estimated $US600 million each year. Patients would also benefit significantly in terms of lower co-payments for epoetin-α. The evidence is supportive of the decision made by the CMS to reimburse the two drugs at the rate reflecting the achievement of comparable clinical effects and therefore reducing the pass-through payments for darbepoetin-α to zero for the 2002–3 fiscal year.  相似文献   
82.
Pneumocephalus is a very rare complication of video-assisted thoracoscopic surgery (VATS). A 66-year-old man developed pneumocephalus secondary to thoracoscopic excision of a neurogenic tumor in the posterior mediastinum. Pneumocephalus was diagnosed by brain computed tomography. Neurosurgical intervention was performed after conservative therapy had failed. The patient's condition had resolved without any neurologic sequelae 2 years later. When a patient has a relatively large amount of chest tube drainage and neurologic symptoms after VATS, the possibility of pneumocephalus due to cerebrospinal fluid leakage must be considered.  相似文献   
83.
本文应用核磁共振法(NMR)测定了几种混合体系的 HLB 值与混合体系中各组分的 HLB 值。实验结果表明,混合体系中各组分在核磁共振图谱中的积分曲线高度也具有加和性。混合体系的 HLB 值是体系中各组分 HLB 值的加权平均值。因此,对混合体系的 HLB 值可以应用 NMR 法直接测定,也可应用 NMR 法测定各组分的 HLB值,通过计算求得,计算值与实测值完全一致。  相似文献   
84.
室间隔夹层瘤的超声诊断(附4例报告)   总被引:1,自引:0,他引:1  
目的 总结室间隔夹层瘤的超声心动图诊断及临床应用价值。方法1985~2005年超声诊断罕见的室间隔夹层瘤4例。超声主要取左室长轴、四腔心、五腔心、大动脉短轴及非标准切面,观察主动脉窦的形态及结构:如扩张窦瘤的大小、窦壁厚度、窦瘤破口的部位、窦瘤破口与室间隔之间的关系,主动脉窦瘤与室间隔夹层瘤之间交通口的大小,测量形成室间隔夹层瘤的大小及夹层瘤左、右室面的厚度,结合彩色多普勒观察心动周期夹层瘤与主动脉窦瘤血流动态变化,频谱多普勒测量窦瘤与室间隔夹层瘤之间的血流速度。结果4例室间隔夹层瘤均为主动脉右窦破人室间隔基底段,且均行手术治疗证实超声诊断。结论超声心动图对室间隔夹层瘤可直接做出诊断,超声诊断价值在于早发现、早诊断、及早治疗,并可为外科选择手术方式提供重要的有价值的依据。  相似文献   
85.
Scintigraphic imaging with (123)I-metaiodobenzylguanidine ((123)I-MIBG) has demonstrated extensive losses of cardiac sympathetic neurons in idiopathic Parkinson's disease (IPD). In contrast, normal cardiac innervation has been observed in (123)I-MIBG studies of multiple-system atrophy (MSA) and progressive supranuclear palsy (PSP). Consequently, it has been hypothesized that cardiac denervation can be used to differentiate IPD from MSA and PSP. We sought to test this hypothesis by mapping the distribution of cardiac sympathetic neurons in patients with IPD, MSA, and PSP by using PET and (11)C-meta-hydroxyephedrine ((11)C-HED). Also, the relationship between cardiac denervation and nigrostriatal denervation was investigated by measuring striatal presynaptic monoaminergic nerve density with PET and (11)C-dihydrotetrabenazine ((11)C-DTBZ). METHODS: (11)C-HED and (11)C-DTBZ scans were obtained for patients with IPD (n = 9), MSA (n = 10), and PSP (n = 8) and for age-matched control subjects (n = 10). Global and regional measurements of (11)C-HED retention were obtained to assess the extent of cardiac sympathetic denervation. (11)C-DTBZ binding was measured in the caudate nucleus, anterior putamen, and posterior putamen. RESULTS: As expected, extensive cardiac denervation was observed in several of the patients with IPD. However, substantial cardiac denervation was also seen in some patients with MSA and PSP. (11)C-DTBZ studies demonstrated striatal denervation in all patients with IPD and in most patients with MSA and PSP. No correlation was found between cardiac (11)C-HED retention and striatal (11)C-DTBZ binding. CONCLUSION: Cardiac sympathetic denervation was found to occur not only in IPD but also in other movement disorders, such as MSA and PSP. This finding implies that scintigraphic detection of cardiac sympathetic denervation cannot be used independently to discriminate IPD from other movement disorders, such as MSA and PSP. Cardiac sympathetic denervation was not correlated with striatal denervation, suggesting that the pathophysiologic processes underlying cardiac denervation and striatal denervation occur independently in patients with parkinsonian syndromes. These findings provide novel information about central and peripheral denervation in patients with neurodegenerative disorders.  相似文献   
86.
87.
Delta hepatitis virus infection in China   总被引:1,自引:0,他引:1  
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China.  相似文献   
88.
89.
内镜下热极治疗消化道疾病93例临床分析   总被引:1,自引:0,他引:1  
目的:观察内镜-热极治疗胃肠息肉、慢性隆起糜烂性胃炎、非静脉曲张性上消化道出血的临床效果。方法:经内镜热极治疗胃肠息肉(47例)、慢性隆起糜烂性胃炎(12例)、非静脉曲张性上消化道出血(34例)共93例患者。根据疾病种类选择不同的温度、时间进行内镜-热极治疗。结果:47例86颗胃肠息肉和12例隆起糜烂性胃炎45颗病灶经治疗后均从局部消失。热极治疗34例上消化道出血病例,有效率为94.1%。全部病例无穿孔及其他严重并发症发生。结论:热极治疗胃肠息肉、隆起糜烂性胃炎和非静脉曲张性上消化道出血效果肯定,安全可靠。  相似文献   
90.
Abstract We report a case of SMV injury in a critically ill patient. The patient was a 19-year-old woman involved in a motor vehicle collision. Her injuries included grade II splenic and renal lacerations, devascularized and lacerated right and transverse colon, a transected transverse mesocolon, a massive shear injury of her abdominal wall, and two partial SMV transections. At initial damage control laparotomy, the SMV was ligated, the devascularized bowel resected and a temporary abdominal closure applied. At re-operation, a mesocaval shunt using saphenous vein was employed. The shunt failed and the patient required a saphenous vein jump graft. Although visceral vascular injuries are rare, ligation of the SMV in a damage control situation is acceptable. This case study is the first to discuss appropriate treatment when interruption to a patient's collateral visceral venous drainage limits the surgeon’s ability to ligate. In these situations, bypass shunts may be successful.  相似文献   
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