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41.
Background contextAlthough the high cost of spine surgery is generally recognized, there is little information on the extent to which payments vary across hospitals.PurposeTo examine the variation in episode payments for spine surgery in the national Medicare population. We also sought to determine the root causes for observed variations in payment at high cost hospitals.Study designAll patients in the national fee for service Medicare population undergoing surgery for three conditions (spinal stenosis, spondylolisthesis, and lumbar disc herniation) between 2005 and 2007 were included.Patient sampleIncluded 185,954 episodes of spine surgery performed between 2005 and 2007.Outcome measuresPayments per episode of spine surgery.MethodsAll patients in the national fee for service Medicare population undergoing surgery for three conditions (spinal stenosis, spondylolisthesis, and lumbar disc herniation) between 2005 and 2007 were identified (n=185,954 episodes of spine surgery). Hospitals were ranked on least to most expensive and grouped into quintiles. Results were risk- and price-adjusted using the empirical Bayes method. We then assessed the contributions of index hospitalization, physician services, readmissions, and postacute care to the overall variations in payment.ResultsEpisode payments for hospitals in the highest quintile were more than twice as high as those made to hospitals in the lowest quintile ($34,171 vs. $15,997). After risk- and price-adjustment, total episode payments to hospitals in the highest quintile remained $9,210 (47%) higher. Procedure choice, including the use of fusion, was a major determinant of the total episode payment. After adjusting for procedure choice, however, hospitals in the highest quintile continued to be 28% more expensive than those in the lowest. Differences in the use of postacute care accounted for most of this residual variation in payments across hospitals. Hospital episode payments varied to a similar degree after subgroup analyses for disc herniation, spinal stenosis, and spondylolisthesis. Hospitals expensive for one condition were also found to be expensive for services provided for other spinal diagnoses.ConclusionsMedicare payments for episodes of spine surgery vary widely across hospitals. As they respond to the new financial incentives inherent in health care reform, high cost hospitals should focus on the use of spinal fusion and postacute care.  相似文献   
42.
Protein-tyrosine kinase p72syk in Fc gamma RI receptor signaling   总被引:2,自引:1,他引:2  
Durden  DL; Liu  YB 《Blood》1994,84(7):2102-2108
In this report we show that gamma-interferon (IFN) induces the expression of the nonreceptor protein tyrosine kinase, p72syk, and that cross-linking the Fc gamma RI receptor in IFN-differentiated U937 cells (U937IF cells) results in the activation of syk kinase. We show that syk is tyrosine phosphorylated (12-fold increase) after Fc gamma RI cross-linking. In vitro kinase assays demonstrate that the specific kinase activity of syk increased eightfold after Fc gamma RI cross- linking. The activation of signal transduction through the Fc gamma RI receptor, as measured by the respiratory burst, is associated with the tyrosine phosphorylation and catalytic activation of the syk kinase. We show that syk coprecipitates with the gamma subunit of the Fc gamma RI, Fc gamma RI gamma. The data suggest that p72syk is involved in signal transduction through the Fc gamma RI receptor, involving the Fc gamma RI gamma subunit.  相似文献   
43.

Background

This paper presents results from a public engagement effort in Nebraska, USA, which measured public opinions about governmental involvement in encouraging the use of electronic health records (EHRs).

Objective

We examine the role of trust in government in contributing to public support for government involvement in the development of EHR technologies. We hypothesize that trust in government will lead to support for federal and state governmental encouragement of the use of EHRs among doctors and insurance companies. Further, because individual experiences with health‐care professionals will reduce perceptions of risk, we expect that support for governmental involvement will be tempered by greater personal experience with the health‐care industry.

Design and Results

Examining a small survey of individuals on the issue, we find general support for both of our hypotheses. The findings suggest that trust in government does have a positive relationship with support for government involvement in the policy domain, but that the frequency of personal experiences with health‐care providers reduces the extent to which the public supports governmental involvement in the development of EHR technology.

Discussion and Conclusion

This inquiry contributes to our understanding of public attitudes towards government involvement in EHRs in the United States specifically and contributes to social science examining links between trust in government and support for governmental activity in the emerging policy domain regarding electronic health records systems.  相似文献   
44.
“Myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” is a recently described tumor entity of the central nervous system with a predilection for origin in the septum pellucidum and a defining dinucleotide mutation at codon 385 of the PDGFRA oncogene replacing lysine with either leucine or isoleucine (p.K385L/I). Clinical outcomes and optimal treatment for this new tumor entity have yet to be defined. Here, we report a comprehensive clinical, radiologic, and histopathologic assessment of eight cases. In addition to its stereotypic location in the septum pellucidum, we identify that this tumor can also occur in the corpus callosum and periventricular white matter of the lateral ventricle. Tumors centered in the septum pellucidum uniformly were associated with obstructive hydrocephalus, whereas tumors centered in the corpus callosum and periventricular white matter did not demonstrate hydrocephalus. While multiple patients were found to have ventricular dissemination or local recurrence/progression, all patients in this series remain alive at last clinical follow‐up despite only biopsy or subtotal resection without adjuvant therapy in most cases. Our study further supports “myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” as a distinct CNS tumor entity and expands the spectrum of clinicopathologic and radiologic features of this neoplasm.  相似文献   
45.
Molecular Imaging and Biology - Peripheral arterial disease (PAD) is an atherosclerotic occlusive disease of the non-coronary vessels that is characterized by lower extremity tissue ischemia,...  相似文献   
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48.
目的:观察经介入途径移植自体骨髓单个核细胞在股骨头坏死治疗中的应用,并评价其疗效。方法:选择2004-07/2005-11在解放军四六三院细胞治疗中心住院的,具有完整随访资料的股骨头坏死确诊患者共54例91髋。纳入确诊股骨头坏死,有关节疼痛、功能障碍等症状患者,性别、年龄不限;排除有严重心力衰竭、严重肾功能异常等不能耐受手术者。符合纳入标准54例,男45例,女9例,12~68岁。按ARCO分期Ⅱ期42髋,Ⅲ期47髋,Ⅳ期2髋。实验对象对治疗的相关内容知情同意并签知情同意。干预措施:抽取患者髂后上嵴骨髓进行单个核细胞悬液的制备。在DSA监视下将采集的单个核细胞混悬液经股动脉行Seldinger法穿刺,穿刺成功后,置入4F动脉鞘,经动脉鞘置入Cobra导管,将导管超选择至闭孔动脉及旋股内外侧动脉,平均注入单个核细胞悬液。术后定期随访症状变化情况,1年后复查X射线或CT,随访疼痛、关节活动度等情况。实验评估:①疼痛指数:无疼痛症状为3分,Harris髋关节评分疼痛分级A级;时有隐痛2分,Harris髋关节评分疼痛B级;轻度疼痛为1分,Harris髋关节评分疼痛C级;中度疼痛为0分,Harris髋关节评分疼痛D级。②功能指数:髋关节屈、伸、展、收、旋转度评分达Harris髋关节活动范围评分4~5分为3分;3~4分为2分;2~3分为1分;小于2分为0分。③X射线平片指数:股骨头形态无变化,应力骨小梁清晰,坏死区明显缩小为3分;坏死区略缩小为2分;治疗前后无明显变化为1分;坏死区扩大为0分。④血管指数:治疗后旋股内、外侧动脉及其分支增粗、增多,延长1cm以上者3分;1~0.5cm者2分;小于0.5cm者1分,无变化者0分。结果:54例患者均完成疼痛症状、关节功能及影像学随访1年。①术后12个月复查疼痛消失9髋,缓解61髋,无缓解21髋,缓解率为76.9%。②关节功能缓解33髋,无缓解58髋,缓解率为36.3%。③1年后X射线平片或CT、MRI示股骨头区可见不同程度的股骨头坏死区骨质密度改变,坏死区有吸收、缩小,股骨头形态变圆滑规整,改善28髋,无缓解或加重63髋,缓解率为30.1%。④12例24髋完成术后12个月复查股骨头供血动脉数字减影血管造影,好转18髋,好转率为72.2%。结论:经介入途径移植自体骨髓单个核细胞治疗股骨头坏死损伤小,可缓解临床相关症状。  相似文献   
49.

Background

Approximately 20 % of patients diagnosed with colorectal cancer will have distant metastases at first presentation (stage IV disease). The effect of removing the primary tumor on survival for patients with stage IV disease with unresectable metastases remains unclear. To address this a meta-analysis of all studies comparing primary tumor resection with chemotherapy alone in cases of stage IV colorectal cancer with unresectable metastases was performed.

Methods

A comprehensive search for published studies examining the effect of primary tumor resection in the setting of colorectal cancer with unresectable metastases was performed. Each study was reviewed and data extracted. Random-effects methods were used to combine data.

Results

There were 21 studies including a total of 44,226 patients that met the inclusion criteria. Resection of the primary tumor in patients with unresectable metastases compared with chemotherapy alone was associated with a lower mortality risk (OR 0.28; 95 % CI 0.165–0.474; P < 0.001), translating into a difference in mean survival of 6.4 months in favor of resection (95 % CI 5.025–7.858, P < 0.001). Patients who underwent resection of the primary tumor were more likely to have liver metastasis only (OR 1.551; 95 % CI 1.247–1.929; P < 0.001), were less likely to have ≥2 metastasis (OR 0.653; 95 % CI 0.508–0.839; P = 0.001), and were less likely to have rectal cancer (OR 0.495; 95 % CI 0.390–0.629; P < 0.001). There was significant cross-study heterogeneity.

Conclusions

Resection of the primary tumor may confer a survival advantage in stage IV colorectal cancer with unresectable metastases but significant selection bias exists in current studies. Randomized controlled trials are essential to validate these findings.  相似文献   
50.
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