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71.

Background

Medical care is obviously an important public service to ensure the health of a nation; however, medical resources are not always used appropriately. ‘Convenience-store consultations’ and inappropriate ambulance transportation represent instances of such improper use by contemporary Japanese citizens in recent years. This article illustrates two examples of misuse and discusses potential countermeasures by considering factors contributing to these behaviours.

Main body

From both public and medical perspectives, these patient behaviours are problematic, causing potential harm to others, negative consequences to such patients themselves, exhaustion of healthcare staff, and breakdown of emergency medical services. Although citizens need to recognize the public nature and scarcity of medical care, the more immediate need may be to identify and to remove personal and social causes inducing such misuse. In addition, healthcare professionals should become more trustworthy. To combat these issues, one-sided penalties such as accusations or sanctions for patients who misuse the system cannot be justified in principle. If measures taken to prevent misuse are ineffective, imposing surcharges or restricting consultations may be considered official policy, but these are not acceptable for several reasons.

Conclusion

For now, we conclude that we must rely on the spontaneous motivation of patients who engage in ‘convenience-store consultations’ and ambulance transportation instead of taking a taxi.
  相似文献   
72.
AIM:To present our initial experience with computed tomography guided radiofrequency ablation(RFA) of osteoid osteoma(OO) in our institution.METHODS:RFA was performed on eight patients(5 males and 3 females) with clinically and radiologically diagnosed OO(femoral neck,n = 4;femoral diaphysis,n = 2;tibial diaphysis,n = 1;fibular diaphysis,n = 1).Ablation was performed using an electrode with a 10-mm exposed tip for a total of 4-6 min at a targeted temperature of 90 degrees Celsius.No cooling system was used.The intervention was accepted as technically successful if the tip of the electrode could be placed within the center of the nidus.We defined clinical success as a disappearance within 2 wk after treatment of symptoms that had manifested at presentation.RESULTS:All procedures were technically successful.No major or immediate complications were observed.Clinical success was achieved in six of eight patients in the first procedure.A second procedure was performed for two patients who had recurrent or continued pain,and one of these cases was successfully treated.The overall rate of success was 87.5%(7/8).No complication was observed.CONCLUSION:Our preliminary results indicate a favorable success rate and no complications and are compatible with the previous reports of RFA of OO.  相似文献   
73.
BACKGROUND: The klotho gene, originally identified by insertional mutagenesis in mice, suppresses multiple aging phenotypes, including atherosclerosis. We tested the hypothesis that the G-395A polymorphism of the klotho gene is associated with increased risk for 2 types of ischemic heart disease in Japanese. METHODS: The study population consisted of 197 patients with coronary heart disease (CAD) who had >75% luminal diameter narrowing, 77 patients with vasospastic angina (VSA) without significant fixed coronary artery disease, and 331 healthy control subjects. RESULTS: The frequency of the A allele carriers of the klotho gene was significantly higher in the CAD group than in the control group (29.9% vs. 19.0%). The unadjusted odds ratio for CAD in the A allele carriers compared with the control group was 1.82 (p=0.004) and a traditional risk-adjusted logistic regression model revealed that the A allele was an independent predictor of CAD (odds ratio, 1.76; p=0.03). In contrast, the frequency of the A allele carriers was not significantly different in the VSA group (23.4%; adjusted odds ratio, 1.18. CONCLUSIONS: The -395A polymorphism of the human klotho gene may be a genetic risk factor for IHD and not for VSA.  相似文献   
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RNA interference (RNAi) offers a novel therapeutic strategy based on the highly specific and efficient silencing of a target gene. Since it relies on small interfering RNAs (siRNAs), a major issue is the delivery of therapeutically active siRNAs into the target tissue/target cells in vivo. For safety reasons, strategies based on vector delivery may be of only limited clinical use. The more desirable approach is to directly apply active siRNAs in vivo. Here, we report the effectiveness of in vivo siRNA delivery into skeletal muscles of normal or diseased mice through nanoparticle formation of chemically unmodified siRNAs with atelocollagen (ATCOL). ATCOL-mediated local application of siRNA targeting myostatin, a negative regulator of skeletal muscle growth, in mouse skeletal muscles or intravenously, caused a marked increase in the muscle mass within a few weeks after application. These results imply that ATCOL-mediated application of siRNAs is a powerful tool for future therapeutic use for diseases including muscular atrophy.  相似文献   
76.

Purpose:

To develop and evaluate a quantitative parameter for staging hepatic fibrosis by contrast enhancement signal intensity and morphological measurements from gadoxetic acid (Gd‐EOB‐DTPA)‐enhanced MR imaging.

Materials and Methods:

MR images were obtained in 93 patients; 75 patients had histopathologically proven hepatic fibrosis and 18 patients who had healthy livers were evaluated. The liver‐to‐muscle signal intensity ratio (SIpost = SIliver/SImuscle), contrast enhancement index (CEI = SIpost/SIpre), and liver‐to‐spleen volumetric ratio (VR = Vliver/Vspleen) were evaluated for staging hepatic fibrosis.

Results:

VR was most strongly correlated with fibrosis stage (7.21; r = ?0.83; P < 0.001). Sensitivity, specificity, and area under the ROC curve demonstrated by linear regression formula generated by VR and CEI in predicting fibrous scores were 100%, 73%, and 0.91, respectively, for the detection of hepatic fibrosis F1 or greater (≥ F1),100%, 87%, and 0.96 for ≥ F2, 74%, 98%, and 0.93 for ≥ F3 and 91%, 100%, and 0.97 for F4.

Conclusion:

The liver‐to‐spleen volumetric ratio and contrast enhancement index were reliable biomarkers for the staging of hepatic fibrosis on Gd‐EOB‐DTPA‐enhanced MR imaging. J. Magn. Reson. Imaging 2012;36:1148–1153. © 2012 Wiley Periodicals, Inc.
  相似文献   
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79.
The most serious problem in current gene therapy is discrepancies between experimental data and actual clinical outcomes, which may be due to insufficient analyses and/or inappropriate animal models. We have explored suicide gene therapy by using various clinically relevant animal models and doubt the clinical use of maximal suicide gene expression, which has been generally recommended. To explore this subject further, we studied what expression level of suicide gene and what promoter led to the maximal clinical benefit in the case of hepatic metastatic cancer in mice. Therapeutic and adverse side effects of 4 adenoviral vectors that express herpes simplex virus thymidine kinase (HSV-tk) under different promoters were scrupulously investigated in 2 mouse models of hepatic metastasis of gastric cancer that possess clinical characteristics. Surprisingly, increases in HSV-tk expression beyond a certain point, achieved by the Rous sarcoma virus long terminal repeat promoter, not only enhanced the adverse side effects of lethal hepatotoxicity and ganciclovir-independent cytotoxicity but also failed to further increase therapeutic potential. Moreover, the carcinoembryonic antigen (CEA) tumor-specific promoter, the therapeutic potential of which had been underestimated, was much more useful-even in the case of low CEA-producing cancer-than had been previously reported. In conclusion, the optimal therapeutic expression level of a suicide gene is a novel concept and a crucial factor for successful cancer gene therapy. The present results, which contradict those of previous studies, alert researchers about possible problems with ongoing and future clinical trials that lack this concept.  相似文献   
80.
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