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51.
We report a case of pretibial sinus and abscess after anterior cruciate ligament reconstruction using a polylactic acid tricalcium phosphate bioabsorbable screw for tibial fixation. Mycobacterium fortuitum was identified as the pathogen after specific mycobacterial cultures were obtained from operative specimens. M. fortuitum is a known but rare cause of periprosthetic infection. Diagnosis is often delayed as routine microbiological cultures do not utilise specific culture requirements for mycobacterial growth. There have been several reports in the literature of sterile abscesses associated with bioabsorbable screws. To our knowledge, this is the first case report of a non-tuberculous mycobacterial infection associated with a bioabsorbable implant. This case illustrates that post-operative Mycobacterium infection can occur as a complication of ACL reconstruction with bioabsorbable screw fixation and should be considered in the differential diagnosis of post-operative periprosthetic infection.  相似文献   
52.
We investigated the applicability of single-use MOSFET detectors as quality-assurance devices. Using ten accelerators available at our institution, we performed output measurements in both water and solid phantoms under photon irradiation. The MOSFET detectors performed well within the manufacturer's specifications, with average deviations of 2.1% and 0.7% for the 6 and 18 MV beams, respectively. The strength of the detector's design, including its wireless set-up, factory calibration and direct read-out, makes the system an acceptable independent quality-assurance device for use in verifying machine output within an accuracy of +/-5%. The MOSFET detectors provide a quick check of machine output, which can be efficacious in detecting gross errors in machine calibrations.  相似文献   
53.
To date, there has been little empirical evidence to support the broader use of value-based insurance design, which lowers copayments for services with high value relative to their costs. To address this lack of data, we evaluated the impact of the value-based insurance program of a US corporation, Pitney Bowes. The program eliminated copayments for cholesterol-lowering statins and reduced them for clopidogrel, a blood clot inhibitor. We found that the policy was associated with an immediate 2.8?percent increase in adherence to statins relative to controls, which was maintained for the subsequent year. For clopidogrel, the policy was associated with an immediate stabilizing of the adherence rate and a four-percentage-point difference between intervention and control subjects a year later. Our study thus provides an empirical basis for the use of this approach to improve the quality of health care.  相似文献   
54.
OBJECTIVE: To investigate the magnetic resonance imaging (MRI) features of well-differentiated hepatocellular carcinoma (HCC). METHODS: We reviewed the MRI of 32 patients with 33 pathologically confirmed well-differentiated HCC. The MRI protocol included T2-weighted imaging with and without fat saturation, dual-phase T1-weighted imaging, and gadolinium-enhanced dynamic study. The signal intensity of each lesion was categorized as hyperintense, isointense, and hypointense with reference to the surrounding liver parenchyma. RESULTS: Thirty-one (93.9%) of 33 well-differentiated HCC were demonstrated on the MRI. The remaining 2 were isointense in all magnetic resonance sequences and, therefore, could not be identified. Most of them were hyperintense (n = 15 [45.4%]) or isointense (n = 16 [48.5%]) on T1-weighted imaging, and hyperintense (n = 12 [36.4%]) or isointense (n = 17 [51.5%]) on T2-weighted imaging. On the dynamic study, 17 lesions (51.5%) were enhanced. CONCLUSIONS: MRI may identify most well-differentiated HCC; however, the imaging appearance is diverse. Biopsy should be performed if magnetic resonance study is inconclusive.  相似文献   
55.
Chen RC  Lii JM  Chen WT  Tu HY  Chiang LC 《European radiology》2006,16(6):1346-1350
We investigated the consequence of repeated transcatheter arterial chemoembolization (TACE) for coexisting small hepatic hemangioma in the treatment of patients with hepatocellular carcinomas and describe the imaging features of embolized hemangioma on the follow-up Lipiodol CT and MR. Six of 431 patients with biopsy-confirmed hepatocellular carcinomas, who underwent TACE, also had seven small hepatic cavernous hemangiomas (0.8∼2.3 cm) in the same area of embolization. All six patients underwent repeated TACE All lesions were evaluated with CT and/or MR for the post-treatment follow-up. The outcomes and imaging features of these embolized hemangiomas were reviewed for the change of tumor size, Lipiodol deposition, enhancing pattern as well as embolization complications. Six of the seven hemangiomas did not depict changes in the size or enhancement pattern without being ablated. One hemangioma showed a decrease in size, but still persisted after TACE. All of the hemangiomas showed Lipiodol deposition for 2∼15 months, in which five hemangiomas depicted irregular rim patterns. There is no complication caused by the procedures. The differentiation of small hepatic hemangiomas from viable HCC is important in the post-TACE follow-up to avoid unnecessary repeated embolization.  相似文献   
56.
目的:研究低氧对大鼠炎症反应和肠铁吸收相关蛋白的影响,阐明低氧影响机体铁状态的调节机制。方法:24只雄性Wistar大鼠随机分为安静对照组(C组)、大强度运动组(E组)和运动后低氧恢复组(HE组)。E组和HE组进行递增负荷跑台运动,坡度0,速度30 m/min,6 d/周,前2周1次/天,后2周2次/天,共4周。训练第1次为1 min,每次递增2 min。HE组每天运动后在13.6%O2的低氧舱中休息,8 h/d。检测各组血清铁,ELISA法检测血清铁调素(hepcidin)和白介素6(IL-6),Western Blot法检测十二指肠铁转运蛋白:血红素转运体1(Heme transport protein1,HCP1)、二价金属离子转运蛋白1(divalent metal transporter 1,DMT1)和膜铁转运蛋白1(Ferroportin 1,FPN1)表达。结果:(1)HE组血清铁和Hb显著高于C组和E组(P<0.01,P<0.05),血清hepcidin、IL-6、白细胞数显著低于E组(P<0.05);而E组血清铁和Hb显著低于C组(P<0.05,P<0.01)。(2)HE组HCP1、DMT1、FPN1均显着高于C组和E组(P<0.01,P<0.05)。结论:适度低氧降低运动机体炎症反应,减少肝分泌hepcidin,促进肠铁吸收,改善机体铁状态,预防运动性铁缺乏。  相似文献   
57.
Numerous root canals filling materials are available in the field of dentistry, based on various formulas that contain a variety of different and partly mutagenic components, such as epoxy resin sealers, Ca(OH)2-based materials, and zinc oxide-eugenol cements. AH Plus root canal sealer will not release formaldehyde according to the manufacturer, although AH26 does. The purpose of this study was to analyze the leakage of lactate dehydrogenase (LDH) from rat hepatocytes after treatment with AH26 and AH Plus root canal sealers in vitro. Hepatocytes from male Sprague-Dawley rats were used to test the cytotoxicity of AH26 and AH Plus. The root canal sealers were mixed and then dissolved in the dimethyl sulfoxide to final concentrations of 0.01%, 0.04%, and 0.1% (wt/vol), with a dimethyl sulfoxide concentration of < 0.05%. Dosage-dependent and time-dependent lactate dehydrogenase leakage values were measured and tested by one-way ANOVA. The results showed that both AH26 and AH Plus are toxic to rat hepatocytes. At a low concentration, AH26 had a higher toxicity than AH Plus to rat hepatocytes.  相似文献   
58.
Radiotherapy has been integrated into the multimodal treatment of hepatocellular carcinoma (HCC), especially of localized hepatic tumor(s) refractory to conventional treatment. However, tumor control remains unsatisfactory mainly because of insufficient dose, and sublethally irradiated tumor may associate with metastasis. Our aim was to assess the effect of combining a molecularly targeted Aurora kinase inhibitor, VE‐465, with radiotherapy in in vitro and in vivo models of human HCC. Human HCC cell lines (Huh7 and PLC‐5) were used to evaluate the in vitro synergism of combining VE‐465 with irradiation. Flow cytometry analyzed the cell cycle changes, while western blot investigated the protein expressions after the combined treatment. Severe combined immunodeficient (SCID) mice bearing ectopic and orthotopic HCC xenografts were treated with VE‐465 and/or radiotherapy for the in vivo response. VE‐465 significantly enhanced radiation‐induced death in HCC cells by a mechanism involving the enhanced inhibition of histone H3 phosphorylation and interruption of cell cycle change. In SCID, mice bearing ectopic HCC xenografts, pretreatment with VE‐465 (20 mg/kg/day × 9 days) significantly enhanced the tumor‐suppressive effect of radiotherapy (5 Gy/day × 5 days) by 54.0%. A similar combinatorial effect of VE‐465 and radiotherapy was observed in an orthotopic model of Huh7 tumor growth by 17.2%. In the orthotopic Huh7 xenografts, VE‐465 significantly enhanced radiation‐induced tumor growth suppression by a mechanism involving the increased apoptosis. VE‐465 is a potent inhibitor of Aurora kinase with therapeutic value as a radiosensitizer of HCC.  相似文献   
59.
Andrographolide (1), an active constituent of Andrographis paniculata, decreased tumor necrosis factor-α (TNF-α)-induced intercellular adhesion molecule-1 (ICAM-1) expression and adhesion of HL-60 cells onto human umbilical vein endothelial cells (HUVEC), which are associated with inflammatory diseases. Moreover, 1 abolished TNF-α-induced Akt phosphorylation. Transfection of an activated Akt1 cDNA vector increased Akt phosphorylation and ICAM-1 expression like TNF-α. In addition, 1 and LY294002 blocked TNF-α-induced IκB-α degradation and nuclear p65 protein accumulation, as well as the DNA-binding activity of NF-κB. Compound 1 exhibits anti-inflammatory properties through the inhibition of TNF-α-induced ICAM-1 expression. The anti-inflammatory activity of 1 may be associated with the inhibition of the PI3K/Akt pathway and downstream target NF-κB activation in HUVEC cells.  相似文献   
60.
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