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Cha CH Lee FT Gurney JM Markhardt BK Warner TF Kelcz F Mahvi DM 《AJR. American journal of roentgenology》2000,175(3):705-711
OBJECTIVE: The objective of this study was to compare CT and sonography for monitoring radiofrequency (RF) lesions in porcine livers. SUBJECTS AND METHODS: RF lesions (n = 12) were created in three pig livers by applying 13 min of current to a multielectrode RF probe with a target temperature of 95 degrees C. Helical unenhanced CT and corresponding axial sonography were performed before ablation, at 2 min, 8 min, and immediately after ablation. Contrast-enhanced CT was performed after ablation. CT scans and sonograms were evaluated by blinded observers for conspicuity of the RF lesion, edge detection (visibility of liver-lesion interface), and artifacts. Hounsfield units were recorded at every time interval, and radiologic-pathologic correlation for lesion size and configuration was performed. RESULTS: Mean size of RF lesions was 3. 03 +/- 0.9 cm. On CT, RF lesions had consistently lower attenuation values than surrounding liver (22.2 H lower than liver at 8 min, p < 0.0001). Echogenicity was variable with sonography (hypoechoic = 59%, hyperechoic = 25%, isoechoic = 16%). Unenhanced CT significantly improved conspicuity, edge detection of RF lesions, and decreased artifacts compared with sonography (p < 0.05). Contrast-enhanced CT improved RF lesion detection, border discrimination, and artifacts compared with sonography (p < 0.05). Unenhanced CT had the best correlation to pathologic size (r = 0.74), followed by contrast-enhanced CT (r = 0.72) and sonography (r = 0.56). Contrast-enhanced CT best correlated with lesion shape, but slightly overestimated size because of areas of ischemia peripheral to the RF lesion. CONCLUSION: In this animal model, unenhanced CT was an effective way to monitor RF ablation compared with sonography because of increased lesion discrimination, reproducible decreased attenuation during ablation, and improved correlation to pathologic size. 相似文献
33.
In the present study, we performed immunohistochemical studies to investigate the changes of Bcl-2 and Bax in the central nervous system of the transgenic mice expressing a human Cu/Zn SOD mutation. In contrast to the controls, a high density of Bcl-2-IR astrocytes were detected all around the gray matter of the spinal cord of the mutant transgenic mice. Bcl-2-IR astrocytes were also detected in the cerebellum and brainstem of transgenic mice. Specific immunoreactivity for Bax was seen in the spinal cord and brainstem of transgenic mice. Immunostaining for Bax was identified only in neurons and not in glial cells. Our present study demonstrated the distribution of Bcl-2 and Bax in detail using immunohistochemical methods through the central nervous system of the transgenic mice, for the first time. 相似文献
34.
Thermosoftening treatment of the nasotracheal tube before intubation can reduce epistaxis and nasal damage 总被引:6,自引:0,他引:6
Kim YC Lee SH Noh GJ Cho SY Yeom JH Shin WJ Lee DH Ryu JS Park YS Cha KJ Lee SC 《Anesthesia and analgesia》2000,91(3):698-701
We evaluated whether a thermosoftening treatment with warm saline of a nasotracheal preformed tube can improve navigability through the nasal passageways and reduce epistaxis and nasal damage. A total of 150 patients were randomly allocated to three groups: Group I (untreated tube group, n = 50), Group II (35 degrees C treated tube group, n = 50), and Group III (45 degrees C treated tube group, n = 50). In Groups II and III, the tubes were softened at 35 +/- 2 degrees C and 45 +/- 2 degrees C with warm saline, respectively. In Group I the tube was prepared at room temperature (25 +/- 2 degrees C). The incidence of epistaxis and nasal damage in Groups II and III was significantly less than that of Group I (P: < 0.05). Despite the more frequent incidence of smooth passage in Group III, no statistical difference was found among the groups. Logistic regression analysis also confirmed that epistaxis was more likely to be reduced when the tube had been thermosoftened (odds ratio = 1.46, 95% confidence interval = 1.02, 2.11). We conclude that simple thermosoftening treatment of the nasotracheal tube with warm saline helps to reduce epistaxis and nasal damage. IMPLICATIONS: Thermosoftening treatment of a nasotracheal tube with warm saline before intubation can effectively reduce epistaxis and nasal damage. This technique is safe, easy, and suitable for all types of tubes and does not require additional implements. 相似文献
35.
Burch PA Richardson RL Cha SS Sargent DJ Pitot HC Kaur JS Camoriano JK 《The Journal of urology》2000,164(5):1538-1542
PURPOSE: We examined the role of paclitaxel and cisplatin as first line therapy for metastatic urothelial cancer. MATERIALS AND METHODS: A total of 34 patients were enrolled in this study, and all were eligible for treatment and assessable for response. Patients received 135 mg./m.2 paclitaxel intravenously for 3 hours followed by 70 mg./m.2 cisplatin for 2 hours every 3 weeks to a maximum of 6 cycles. RESULTS: Of the patients 70% experienced a major response to treatment, which was partial/regression in 38% and complete in 32%. Toxicity was manageable with no episodes of grade 4 leukopenia or thrombocytopenia. Nonhematological toxicities included primarily nausea, anorexia and neuropathy, which rarely were severe. CONCLUSIONS: This regimen of paclitaxel and cisplatin is effective, safe and convenient to administer in an outpatient setting for advanced urothelial cancer. 相似文献
36.
Matsuo H Tsukada S Nakata T Chairoungdua A Kim DK Cha SH Inatomi J Yorifuji H Fukuda J Endou H Kanai Y 《Neuroreport》2000,11(16):3507-3511
Amino acid transport system L has been proposed to be one of the major nutrient transport systems at the blood-brain barrier. Using immunohistochemical analyses, a system L transporter LAT1 was shown to be expressed in the brain capillary endothelial cells in rats. Because LAT1 was coexpressed with 4F2 heavy chain which brings LAT1 to the plasma membrane, LAT1 is proposed to be functional in the plasma membrane of brain capillary endothelial cells. Both LAT1 and 4F2hc immunoreactivities were detected in a double line appearance surrounding endothelial cell nuclei, suggesting both proteins are present in the luminal and abluminal membranes. LAT1 is, thus, a blood-brain barrier system L transporter responsible for the permeation of aromatic or branched-chain amino acids and amino acid-related drugs such as L-DOPA. 相似文献
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39.
观察利用微信干预增加青光眼患者体力活动的效果。方法:前瞻性随机对照研究。选择2018年 6-12月于温州医科大学附属眼视光医院门诊确诊的青光眼患者102例作为研究对象。利用Excel生成的随机数随机分为对照组和干预组。对照组患者仅在门诊入组时进行运动宣教,并告知其可增加每天的运动步数;干预组患者入组时进行运动宣教,告知其可增加每天的运动步数的同时,加入微信群进行运动提醒干预。所有患者均需利用运动监测仪器完成基线1周和随访1个月的体力活动监测。采用卡方检验、独立样本t检验、Mann-Whitney U检验、配对t检验及Wilcoxon符号秩检验进行数据分析。结果:排除30例基线运动量较大(步数>12 000步/d)、依从性不好及其他原因失访的患者,最终纳入72例(对照组42例,干预组30例)。干预组患者干预后的步数(t=4.94,P<0.001),运动消耗的卡路里(Z=-2.87,P=0.004),代谢当量(Z=-3.30,P=0.001),中等强度体力活动时间(Z=-2.89, P=0.004),高强度体力活动时间(t=2.57,P=0.016)及中高强度体力活动时间(Z=-3.01,P=0.003)均较基线增加;轻度体力活动时间(t=-2.14,P=0.041)和久坐静止不动次数较干预前减少(t=-2.76, P=0.022)。对照组随访的步数也较基线增加(t=3.29,P<0.001),轻度体力活动时间较基线减少(t=-2.57,P=0.014)。另外,干预组的高强度体力活动时间增加量(随访-基线)(Z=-3.04,P=0.002)和超高强度体力活动时间增加量(Z=-2.06,P=0.040)明显高于对照组,差异均有统计学意义。结论:微信干预可以增加青光眼患者的每天运动步数和中高强度体力活动时间,减少患者的轻度体力活动时间和久坐静止次数。 相似文献
40.
Y.W. Kim N.K. Kim B.S. Min H. Kim J. Pyo M.J. Kim S.H. Cha 《European journal of surgical oncology》2008