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31.
C. Marcelin J. Leiner S. Nasri F. Petitpierre Y. Le Bras M. Yacoub N. Grenier J.C. Bernhard F. Cornelis 《Diagnostic and interventional imaging》2018,99(1):3-8
Purpose
To compare diameters of in vivo microwave ablation (MWA) performed in swine kidneys with ex vivo diameters, and to correlate with ablation work (AW), a new metric reflecting total energy delivered.Material and methods
Eighteen in vivo MWA were performed in 6 swine kidneys successively using one or two antennas (MicroThermX®). Ablation consisted in delivering power (45–120 W) for 5–15 minutes. Ex vivo diameters were provided by the vendors and obtained on bovine liver tissue. AW was defined as the sum of (power)*(time)*(number of antennas) for all phases of an ablation (in kJoules). Kidneys were removed laparoscopically immediately after ablation. After sacrifice, ablations zones were evaluated macroscopically, and maximum diameters of the zones were recorded. Wilcoxon sum rank test and Pearson's correlation were used for comparisons.Results
For a single antenna (n = 12), the in vivo diameters ranged from 12 to 35 mm, and 15–49 mm for 2 antennas (n = 6). The in vivo diameters remained shorter than ex vivo diameters by 8.6% ± 30.1 on 1 antenna and 11.7% ± 26.5 on 2 antennas (P = 0.31 and 0.44, respectively). AW ranged from 13.5 to 108 kJ. Diameters increased linearly with AW both with 1 and 2 antennas, but only moderate correlations were observed (r = 0.43 [95% confidence interval: ?0.19; 0.81], P = 0.16; and 0.57 [?0.44; 0.95], P = 0.24, respectively).Conclusion
Although diameters after in vivo renal MWA increased linearly with AW, the moderate correlation and wide standard deviations observed may justify a careful imaging monitoring during treatment delivery and settings adaptation, if needed, for optimal ablation. 相似文献32.
采用免疫型肝硬化大鼠建立慢加急性肝衰竭模型方法的研究 总被引:2,自引:0,他引:2
目的对人血清白蛋白免疫诱导型肝硬化大鼠给予不同急性打击,探索建立与人慢加急性肝衰竭组织病理表现相似、实用性、重复性好的实验模型、方法用人血清向蛋白免疫诱导建立肝硬化大鼠模型,至肝纤维化达4级时随机分组,组一(n=6)给予1.2g/kg的D.氨基半乳糖腹腔注射;组二(n=6)给予30mg/kg脂多糖尾静脉注射;组i(n=6)给予D-氨基半乳糖400mg/kg+脂多糖100trg/kg同时腹腔注射;组四(n:4)继续给人血清白蛋白静脉注射,计算每组动物自然生存时间及死亡率、观察各脏器组织病理变化。结果组一5只大鼠给药后39~52h之内死亡,肝组织病理显示肝硬化基础上发生弥漫大小泡脂肪变性,仅见小片坏死灶;组二大鼠均存活良好,给药后3天后处死肝组织未见坏死性病变。组三5只大鼠在13~19h内死亡,肝脏病理表现为再生结节大块或亚大块坏死,肝细胞凋广明硅,增生的纤维间隔完整保留。结论对人血自蛋白免疫诱导型肝硬化大鼠给予D-氨基半乳糖/脂多糖联合急性攻击可建立慢加急性肝衰竭模型,而单独给大剂量D-氨基半乳糖或脂多糖不能使肝硬化大鼠发生肝脏大块或亚大块坏死。 相似文献
33.
目的研究适用于中医医案文献自动分词的方案。方法使用层叠隐马模型作为分词模型,建立相关中医领域词典及测试语料库,对语料库中古代医案文献和现代医案文献各300篇进行分词及评测。结果在未使用中医领域词典时,两类医案文献分词准确率均为75%左右;使用中医领域词典后,古代医案文献的分词准确率达到90.73%,现代医案文献的分词准确率达到95.66%。在未使用中医领域词典时,词性标注准确率古代医案文献为56.74%,现代医案文献为64.81%;使用中医领域词典后,现代医案文献为91.45%,明显高于古代医案文献的78.47%。结论现有分词方案初步解决了中医医案文献的分词问题,对现代医案文献的词性标注也基本正确,但古代医案文献的词性标注影响因素较多,还需进一步研究。 相似文献
34.
Chronic abdominal pain is a common gastrointestinal symptom experienced by patients. We have previously shown that IBS patients with visceral hypersensitivity also have evidence of thermal hypersensitivity of the hand and foot that is reversed by rectal lidocaine jelly. We have also recently developed an animal model of chronic visceral and somatic hypersensitivity in rats treated with intracolonic trinitrobenzene sulfonic acid (TNBS). The objective of the current study was to determine the effects of intracolonic lidocaine on visceral/somatic hypersensitivity in TNBS-treated rats. A total of 20 hypersensitive rats received either 20mg intracolonic lidocaine (n=10) or saline jelly (n=10). In comparison to saline jelly, intracolonic lidocaine jelly reduced responses to nociceptive visceral/somatic stimuli in hypersensitive rats. The effects were present within 5-30 min after administration of lidocaine and lasted for 6h. Lidocaine had no effects on recovered rats or control rats that had originally been treated with intracolonic saline instead of TNBS. Local anesthetic blockade of peripheral impulse input from the colon reduces both visceral and somatic hypersensitivity in TNBS-treated rats, similar to results in IBS patients. The results provide further evidence that visceral and secondary somatic hypersensitivity in a subset of TNBS-treated rats reflect central sensitization mechanisms maintained by tonic impulse input from the colon. This study evaluates the reversal of visceral/somatic hypersensitivity in a subset of TNBS-treated rats with intracolonic lidocaine. This animal model may be used in the future to study the mechanisms of local anesthetic agents applied to the gut to reduce visceral pain. 相似文献
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The number of animals used in research has increased with the advancement of research and development in medical technology. Every year, millions of experimental animals are used all over the world. The pain, distress and death experienced by the animals during scientific experiments have been a debating issue for a long time. Besides the major concern of ethics, there are few more disadvantages of animal experimentation like requirement of skilled manpower, time consuming protocols and high cost. Various alternatives to animal testing were proposed to overcome the drawbacks associated with animal experiments and avoid the unethical procedures. A strategy of 3 Rs (i.e. reduction, refinement and replacement) is being applied for laboratory use of animals. Different methods and alternative organisms are applied to implement this strategy. These methods provide an alternative means for the drug and chemical testing, up to some levels. A brief account of these alternatives and advantages associated is discussed in this review with examples. An integrated application of these approaches would give an insight into minimum use of animals in scientific experiments. 相似文献
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Wan-Yin Shi Jian-Ping Gu Lei Yan Xu He 《Minimally invasive therapy & allied technologies》2016,25(2):99-106
Objective: Endoleaks constitute the main concern regarding the use of covered stents in the treatment of intracranial aneurysms. We investigated immediate/late endoleaks after stent-graft placement for the treatment of experimentally created carotid fusiform aneurysm (FA) in a canine model. Material and methods: Eighteen carotid FAs in nine dogs receiving covered stents were followed. Their procedural and angiographic data were collected immediately and six months after stenting. Univariate analysis and multivariate logistic regression analysis were performed to determine the factors predictive of immediate/late endoleaks. Receiver operating characteristic curve analysis was performed to determine the best cutoff values of the independent factors. Results: All carotid FAs were successfully treated with Willis covered stents and received a six-month follow-up. The rate of immediate and late endoleaks after stenting was 38.89% and 16.67%, respectively. Anchoring length was identified as independent predictor of immediate endoleaks (P?=0.037) and its best cutoff value was 3.06mm (95% confidence interval: 2.39-3.72). No parameters were identified to be independent predictors of late endoleaks. Conclusions: Treating carotid FAs with Willis covered stents is technically feasible. Most endoleaks heal spontaneously and significantly correlate with anchoring length. 相似文献