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31.
Objectives To investigate the magnitude and characteristics of the economic burden resulting from acute pesticide poisoning (APP) in South Korea. Methods The total costs of APP from a societal perspective were estimated by summing the direct medical and non‐medical costs together with the indirect costs. Direct medical costs for patients assigned a disease code of pesticide poisoning were extracted from the Korean National Health Insurance Reimbursement Data. Direct non‐medical costs were estimated using the average transportation and caregiving costs from the Korea Health Panel Survey. Indirect costs, incurred by pre‐mature deaths and work loss, were obtained using 2009 Life Tables for Korea and other relevant literature. Results In 2009, a total of 11 453 patients were treated for APP and 1311 died, corresponding to an incidence of 23.1 per 100 000 population and a mortality rate of 2.6 per 100 000 population in South Korea. The total costs of APP were estimated at approximately US$ 150 million, 0.3% of the costs of total diseases. Costs due to pre‐mature mortality accounted for 90.6% of the total costs, whereas the contribution of direct medical costs was relatively small. Conclusion Costs from APP demonstrate a unique characteristic of a large proportion of the indirect costs originating from pre‐mature mortality. This finding suggests policy implications for restrictions on lethal pesticides and safe storage to reduce fatality and cost due to APP.  相似文献   
32.
Background: Concept maps can assist learning by integrating new information with existing cognitive structure to facilitate meaningful understanding. The benefits of testable concept maps to illustrate cause-and-effect sequences in the pathogenesis of disease have not yet been determined. Purpose: A controlled trial was employed to evaluate the learning benefits of testable pathogenesis maps. Methods: Consecutive cohorts of junior medical students allocated to control and study groups participated in case-based pathology practical classes. Online testable pathogenesis maps were integrated into classes for the study group. An online quiz and questionnaire were used to evaluate outcomes. Results: The study group scored significantly higher on the quiz ( p= .014), including significantly better performance in topics covered by pathogenesis maps ( p= .049). The study group's questionnaire responses regarding pathogenesis maps were overwhelmingly positive. Conclusions: Testable pathogenesis maps significantly improved medical students’ understanding of the pathogenesis of disease. Wider use of such maps should be explored.  相似文献   
33.
We have shown previously that electrical stimulation of the motor cortex reduces spontaneous painlike behaviors in animals with spinal cord injury (SCI). Because SCI pain behaviors are associated with abnormal inhibition in the inhibitory nucleus zona incerta (ZI) and because inactivation of the ZI blocks motor cortex stimulation (MCS) effects, we hypothesized that the antinociceptive effects of MCS are due to enhanced inhibitory inputs from ZI to the posterior thalamus (Po)—an area heavily implicated in nociceptive processing. To test this hypothesis, we used a rodent model of SCI pain and performed in vivo extracellular electrophysiological recordings in single well-isolated neurons in anesthetized rats. We recorded spontaneous activity in ZI and Po from 48 rats before, during, and after MCS (50 μA, 50 Hz; 300-ms pulses). We found that MCS enhanced spontaneous activity in 35% of ZI neurons and suppressed spontaneous activity in 58% of Po neurons. The majority of MCS-enhanced ZI neurons (81%) were located in the ventrorateral subdivision of ZI—the area containing Po-projecting ZI neurons. In addition, we found that inactivation of ZI using muscimol (GABAA receptor agonist) blocked the effects of MCS in 73% of Po neurons. Although we cannot eliminate the possibility that muscimol spread to areas adjacent to ZI, these findings support our hypothesis and suggest that MCS produces antinociception by activating the incertothalamic pathway.PerspectiveThis article describes a novel brain circuit that can be manipulated, in rats, to produce antinociception. These results have the potential to significantly impact the standard of care currently in place for the treatment of patients with intractable pain.  相似文献   
34.
金属硫蛋白和肿瘤增殖抗原在肾癌组织中的表达及意义   总被引:4,自引:0,他引:4  
目的 探讨金属硫蛋白 (MT)和肿瘤增殖抗原 (Ki 67)在肾癌组织中的表达及意义。 方法 应用免疫组化SABC法检测 5 9例肾癌患者组织标本及 19例正常肾组织标本中MT及Ki 67蛋白表达 ,流式细胞术检测DNA含量及S期比例。 结果 MT在肾癌及正常肾组织中的阳性表达率分别为 5 2 .5 %和 78.9% (P <0 .0 5 ) ;G1表达率高于G2 、G3(P <0 .0 1) ,Ⅰ、Ⅱ期高于Ⅲ、Ⅳ期 (P <0 .0 5 ) ,有无淋巴结转移之间差别有显著性意义 (P <0 .0 1) ,不同直径肿瘤之间差别无显著性意义 (P>0 .0 5 )。MT( )及MT( - )患者术后 5年生存率分别为 5 8.1%和 2 8.6% (P <0 .0 5 )。肾癌组织Ki 67指数高于正常肾组织 (P <0 .0 1) ,且与病理分级、临床分期相关 ;Ki 67指数较高者 ,MT表达率较低 ,MT表达率及Ki 67指数分别与S期比例显著相关。 结论 MT及Ki 67蛋白可能参与肾癌的发生、进展及转移过程 ,可作为肾癌细胞增殖及预后估计的参考指标。  相似文献   
35.
36.
BACKGROUND: Epoxyeicosatrienoic acids (EETs) are endothelium-derived hyperpolarizing factors that contribute renal protective actions. The aim of this study was to identify the association between genetic variations in soluble epoxide hydrolase (EPHX2, EET-metabolizing enzyme) and kidney allograft dysfunction. MATERIALS AND METHODS: Data from 204 kidney transplant donor-recipient pairs were examined for polymorphisms of exon 8 (R287Q, rs751141 G/A) and 3' untranslated region (3' UTR, rs1042032 A/G) of the EPHX2 gene and correlated with clinical data. RESULTS: The mean duration of follow-up for recipients was 58 +/- 45.3 months who were 39 +/- 11.8 years old at the time of operation and displayed estimated glomerular filtration rate (eGFR) of 68 +/- 16.5 mL/min/1.73 m2 at 1 month after transplantation. AA, AG, and GG genotype frequencies in 3' UTR were 28%, 55%, and 16%, respectively. Twenty-one recipients experienced allograft dysfunction with eGFR <30 mL/min/1.73 m2; 10 had AA genotype of rs1042032 polymorphism (chi-square test; A/A vs A/G+G/G; P = .04). Recipients without rs1042032 polymorphism variant allele showed a significant risk for allograft dysfunction (A/A vs A/G+G/G; P = .04; odds ratio, 2.65; 95% confidence interval [CI], 1.03-6.81). Multivariate analysis of the characteristics of patients using a Cox proportional hazard model showed that the AA genotype of rs1042032 polymorphism was predictive of allograft dysfunction (Hazard Ratio = 3.26; P = .04; 95% CI, 1.08-9.59). CONCLUSION: The present study suggested that the presence of the rs1042032 variant allele in EPHX2 was associated with a protective role for allograft function.  相似文献   
37.
Only 5% to 10% of metastatic and primary liver tumors are amenable to surgical resection. Hepatic cryoablation has increased the number of patients who are suitable for curative treatment. The aim of this study was to evaluate survival and intrahepatic recurrence in patients treated with cryoablation and resection. From June 1994 to July 1999, thirty-eight surgically unresectable patients underwent a total of 42 cryoablative procedures for 65 malignant hepatic lesions. Twenty patients underwent cryoablation alone, and 18 patients were treated with a combination of resection and cryoablation, with a minimum of 18 months’ follow-up. The 38 patients had the following malignancies: primary hepatocellular carcinoma (n = 8) and metastases from colorectal cancer (n = 21), neuroendocrine tumors (n = 3), ovarian cancer (n = 3), leiomyosarcoma (n = 1), testicular cancer (n = 1), and endometrial cancer (n = 1). Patients were evaluated preoperatively with spiral CT scans and intraoperatively with ultrasound examinations for lesion location and cryoprobe guidance. Local recurrence was detected by CT. Major complications included bleeding in three patients and acute renal failure, transient liver insufficiency, and postoperative pneumonia in one patient each. Two patients (5%) died during the early postoperative interval; mean hospital stay was 7.1 days. Median follow-up was 28 months (range 18 to 51 months). Overall survival according to Kaplan-Meier analysis was 82%, 65%, and 54% at 12, 24, and 48 months, respectively. Forty-eight-month survival was not significantly different between those patients undergoing cryoablation alone (64%) and those treated with a combination of resection and cryoablation (42 %). Diseasefree survival at 45 months was 36% for patients undergoing cryoablation plus resection compared to 25% for those undergoing cryoablation alone. Local recurrences were detected at five cryosurgical sites, for a rate of 12% overall (5 of 42), 11% (2 of 18) for patients in the cryoablation plus resection group, and 12% (3 of 24) for those in the cryoablation alone group. For patients with colorectal metastases, survival was 70% at 30 months compared to 33% for hepatocellular cancer and 66% for other types of tumors. Patients with tumors larger than 5 cm or numbering more than three did not have significantly decreased survival. Cryoablation of hepatic tumors is a safe and effective treatment for some patients not amenable to resection. The combination of cryoablation and resection results in survival comparable to that achieved with cryoablation alone. Presented at the Forty-First Annual Meeting of The Society for Surgery of the Alimentary Tract, San Diego, Calif., May 21–24, 2000.  相似文献   
38.
For patients who are suffering from neurogenic lower urinary tract dysfunction, intermittent urinary catheterization is an efficient way to empty the bladder.1 However, the method may result in various complications. Herein we present a rare complication of extraperitoneal abscess owing to intermittent urinary catheterization in a 62-year-old male who had cervical spine injury and was treated with intermittent urethral catheterization for neurogenic lower urinary tract dysfunction. Treatment and a literature review are also described.  相似文献   
39.
目的:观察柚皮素(naringenin,NAR)对H2O2诱导的SH-SY5Y细胞氧化应激损伤的影响,并探索其机制。方法:通过CCK-8检测细胞存活率,筛选出H2O2的半数致死浓度,用该浓度H2O2同时加入20、40、80 μmol/L柚皮素处理SH-SY5Y细胞4 h,通过CCK-8检测细胞存活率,选择适宜柚皮素浓度。按所选H2O2和柚皮素浓度进行后续实验。将实验分为3组。control组:细胞不进行任何干预处理;H2O2组:只加入600 μmol/L H2O2;H2O2+NAR组:同时加入600 μmol/L H2O2与40 μmol/L柚皮素。4 h后,通过ANNEXIN V-FITC/PI凋亡检测试剂盒检测细胞凋亡率,DCFH-DA荧光探针检测细胞内活性氧(reactive oxy-gen species,ROS),Western blot检测哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)、核糖体蛋白S6激酶(p70 ribosomal S6 kinase,p70S6K),以及各自磷酸化形式蛋白[p-mTOR(Ser2448)、p-p70S6K(Thr389)],用胰岛素受体底物-1(insulin receptor substrate 1,IRS1)及其丝氨酸636+639位点磷酸化[p-IRS1(Ser636+Ser639)]蛋白的表达来观察胰岛素抵抗(insulin re-sistance,IR)。结果:H2O2降低SH-SY5Y细胞的存活率,呈剂量依赖性,600 μmol/L浓度为半数致死剂量。柚皮素明显降低了H2O2诱导的SH-SY5Y细胞死亡,最适剂量为40 μmol/L。与control组比,H2O2明显增加了细胞凋亡率、胞内ROS的产生,降低了p-mTOR(Ser2448)、p-p70S6K(Thr389)的表达,增加了p-IRS1(Ser636+Ser639)蛋白的表达(P<0.05);加入柚皮素后,相对于H2O2组,上述作用明显减弱(P<0.05)。结论:在体外氧化应激模型中,柚皮素能明显降低细胞内ROS的积累,提高细胞的存活率。其机制可能与激活mTOR/p70S6K信号通路、改善IR有关。  相似文献   
40.
Law M  Cha S  Knopp EA  Johnson G  Arnett J  Litt AW 《Radiology》2002,222(3):715-721
PURPOSE: To determine whether perfusion-weighted and proton spectroscopic MR imaging can be used to differentiate high-grade primary gliomas and solitary metastases on the basis of differences in vascularity and metabolite levels in the peritumoral region. MATERIALS AND METHODS: Fifty-one patients with a solitary brain tumor (33 gliomas, 18 metastases) underwent conventional, contrast material--enhanced perfusion-weighted, and proton spectroscopic MR imaging before surgical resection or stereotactic biopsy. Of the 33 patients with gliomas, 22 underwent perfusion-weighted MR imaging; nine, spectroscopic MR imaging; and two underwent both. Of the 18 patients with metastases, 12 underwent perfusion-weighted MR imaging, and six, spectroscopic MR imaging. The peritumoral region was defined as the area in the white matter immediately adjacent to the enhancing (hyperintense on T2-weighted images, but not enhancing on postcontrast T1-weighted images) portion of the tumor. Relative cerebral blood volumes in these regions were calculated from perfusion-weighted MR data. Spectra from the enhancing tumor, the peritumoral region, and normal brain were obtained from the two-dimensional spectroscopic MR acquisition. The Student t test was used to determine if there was a statistically significant difference in relative cerebral blood volume and metabolic ratios between high-grade gliomas and metastases. RESULTS: The measured relative cerebral blood volumes in the peritumoral region in high-grade gliomas and metastases were 1.31 +/- 0.97 (mean +/- SD) and 0.39 +/- 0.19, respectively. The difference was statistically significant (P <.001). Spectroscopic imaging demonstrated elevated choline levels (choline-to-creatine ratio was 2.28 +/- 1.24) in the peritumoral region of gliomas but not in metastases (choline-to-creatine ratio was 0.76 +/- 0.23). The difference was statistically significant (P =.001). CONCLUSION: Although conventional MR imaging characteristics of solitary metastases and primary high-grade gliomas may sometimes be similar, perfusion-weighted and spectroscopic MR imaging enable distinction between the two.  相似文献   
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