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81.
肿瘤热消融技术是在现代影像学基础上诞生、发展的新技术。实时监测与术后即刻评估消融范围是保证治疗安全、取得良好疗效的关键。超声弹性成像作为一种新的超声组织定征技术,在肿瘤热疗监测方面正受到越来越多的关注。本文介绍了弹性成像在离体实验、动物实验、临床实验肿瘤热疗无创监测中的应用研究,概述了国内外研究现状,并讨论了弹性成像技术在肿瘤无创监测中的未来研究方向。  相似文献   
82.
Increasing consumption of chicken results in generation of large amounts of wastes that need to be disposed of properly. Chicken feathers constitute about 5–10% of the weight of the chicken and thus they comprise a significant portion of the poultry wastes. Disposal of waste chicken feathers is problematic in that they do not readily degrade after landfilling, there is increasing shortage of landfill space, and they are contaminated with microbial biomass that makes them hazardous waste. Feathers contain ~91% keratin protein and thus, potentially, feathers can be beneficiated into high-value compounds or products comprised of keratin proteins or keratin fibres. Thus, valorisation of feathers could be a viable option for sustainable disposal of the waste. Characterisation of physicochemical properties of the chicken feather is an essential step to identifying possible avenues for valorisation of this waste biomass. While chemical, physical and morphological properties of chicken feathers and related potential valorisation routes have described by the authors, identification of their mechanical, thermal and electrical properties have not been reported and this information is necessary to have a complete and comprehensive characterisation of waste chicken feathers. Hence, in this research, the mechanical, thermal and electrical properties of feathers were determined and evaluated to ascertain suitability of the feathers for production of high-value materials. The feathers and fractions thereof were characterised by TGA/DSC, Instron (material and structural testing), Dynamic Mechanical Analyser, and a two-probe measurement of resistivity instrument. Under heated conditions, the TGA of chicken feathers confirmed the occurrence of three zones of weight loss. The TGA/DSC results revealed a glass transition temperature around 67 °C and a melting temperature ~230 °C in the crystalline phase. The tenacity of chicken feather barbs at maximum load was ~16.93 cN/tex. The results from electrical properties indicated that chicken feather fractions have low conductivity. Overall, the results indicate that chicken feathers have potential to be used in a variety of applications such as electrical insulator materials, yarn production for use in textiles, nonwoven fabric production, filler for winter clothing, geotextile and construction materials.  相似文献   
83.
Neuropathic pain is caused by injury of the peripheral or central nervous system. The neurological examination of the sensory system in neuropathic pain patients guides the anatomical localization of the injury. Among the sensory modalities to be tested, priority should be given to those subserved by small peripheral sensory fibers or by the spinothalamic tract that most commonly are abnormal in neuropathic pain patients. Testing of cold and warm perception was traditionally carried out in the clinic using tubes filled with water at different temperatures, a cumbersome method that has limited the routine examination of these sensory modalities. The Lindblom roller offers a practical and effective method of readily testing temperature perception and is among the best available clinical tools for delineating the anatomical boundaries of a sensory abnormality. Routinely use of the Lindblom roller shall be standard bedside clinical assessment of neuropathic pain patients. To exemplify this statement we describe two patients affected by complex and fluctuating painful sensory abnormalities caused by an extradural mass compressing the spinal cord. The level of the injury was readily localized with a roller kept at room temperature.  相似文献   
84.
目的通过对甲状腺乳头状癌(PTC)热消融后复发再手术病例进行分析,探讨热消融是否能用于可手术的PTC患者。 方法回顾性分析2015年5月至2019年8月间青岛大学附属烟台毓璜顶医院甲状腺外科热消融治疗后再手术的23例患者资料。所有患者在外院行热消融治疗前均行甲状腺细针穿刺(FNA),20例穿刺病理为PTC,3例不除外PTC可能。15例行甲状腺癌根治术,1例行侧颈部淋巴结改良根治术,7例患者因存在复发结节压迫症状,行甲状腺腺叶切除术。 结果再手术后石蜡病理示,56.52%(13/23)见癌细胞,43.47%(10/23)未查见癌细胞,30.43%(7/23)见中央区淋巴结转移。2例消融对侧发现新发甲状腺结节,术后石蜡病理证实为PTC。 结论热消融治疗PTC无法彻底处理原发灶,达不到根治效果。对于可行手术治疗的PTC患者,不建议热消融治疗。  相似文献   
85.
IntroductionThis study evaluated trends in demographics and outcomes of cutaneous burns over a forty-year period at a Canadian burn centre.MethodsRetrospective review was performed of all consecutive adult burn admissions to the Vancouver General Hospital (VGH) between 1976 and 2015. Comparison was made to the 2016 American Burn Association – National Burn Repository.ResultsThere were 4105 admissions during study period. Both overall admissions and admissions per 100,000 BC residents declined (p < 0.0001). Males represented three quarters of admissions. There was a decrease in large burns (p < 0.05). Flame burns were most commonly associated with larger TBSA, ICU stays, and mortality.Mortality decreased from 11.3% to 2.8% (p < 0.05). Factors found to affect mortality included: increased length of stay, age and burn size, male gender, and number of complications. Baux50 and rBaux50 increased, from 102.8 to 116.7 and 112.2 to 125.3 respectively (p < 0.05, respectively).ConclusionsThis study represents the largest report on burn epidemiology in Canada. The incidence of burns has decreased significantly over the last forty years. Mortality has improved over this time frame, as evident by increases in Baux50 and rBaux50 scores. Further data is largely in concurrence with that of the National Burn Repository’s amalgamation of US centres.  相似文献   
86.
AimThe objective of this study was to examine the thiol–disulfide profile tests in patients suffering from burn injuries.MethodsThis case–control study comprised 48 patients with thermal burn injuries and 61 healthy individuals. Thiol–disulfide tests were conducted in both groups, and also, the changes of thiol–disulfide parameters were analyzed at zero time and on days 3, 7, 15, and 30 of the admission in patients with burn injuries.ResultsThe patients had significantly decreased native and total thiol levels and native thiol/total thiol ratios, and significantly increased disulfide/native thiol and disulfide/total thiol ratios compared to control individuals (p < 0.001 for all). The variations of native thiol levels, total thiol levels, and disulfide/native thiol ratios were significantly different over time in patients with burn injuries (p < 0.001, p < 0.001, p < 0.05, respectively). There were strong associations with the clinical parameters and thiol–disulfide profile tests (p < 0.05 for all).ConclusionThere was a metabolic disturbance of the thiol–disulfide system among patients with burn injuries. The courses of thiol–disulfide variables in time overlapped with the burn mechanism. Strong associations provide that thiol–disulfide homeostasis might be a notable key for evaluating the severity of burns and predicting the survival.  相似文献   
87.
BackgroundHemodynamic aberrations after severe burns are treated with aggressive intravenous (IV) fluid resuscitation however, oral resuscitation has been proposed in resource poor scenarios. Previously we have shown that animals receiving oral fluid following burns were able to recover kidney function. However, immune function such as circulating and splenic immune cell populations after oral or intravenous fluid administration was not examined. Herein, we perform a follow up analysis of splenic tissue and plasma from the previous animal study to examine the splenic response following these resuscitation strategies after burn injury.MethodsEighteen anesthetized Yorkshire swine receiving 40%TBSA contact burns were randomized to receive either: (1) no fluids (Fluid Restricted; negative control), (2) 70 mL/kg/d Oral Rehydration Salt solution (Oral), or (3) 2 mL/kg/%TBSA/d of lactated Ringer’s solution IV. Blood was drawn for blood cell analysis, and CT scans were performed before and 48 h post-burn, at which point spleens were harvested for histological, Western blot, and RT-PCR analyses.ResultsSplenic artery diameter decreased by −0.97 ± 0.14 mm in fluid-restricted animals, while IV led to an increase of 0.68 ± 0.30 mm. No significant differences were detected in white and red pulp. IV fluids reduced the population of splenic monocytes (CD163; P = 0.001) and neutrophils (MPO protein; P = 0.13), as well as cytokines IL-8 (P = 0.003), IFN-γ (P = 0.11) and TNFα (P = 0.05). Additionally, withholding IV fluids consistently decreased the expression of FoxP3, CCR6, and IL17β in spleen, suggesting a shift in T-cell phenotype with IV resuscitation.ConclusionsThe route of fluid administration has a minor influence on the changes in circulating and splenic leukocytes post-burn in the acute phase. Further research is needed to help guide resuscitation approaches using immunologic markers of splenic function following burns.  相似文献   
88.

Background

In low- and middle-income countries burn injuries remain responsible for a large burden of death and disability. Given an annual worldwide incidence of almost 11 million new individuals affected per year, major burn injuries have a higher annual incidence than HIV and tuberculosis combined.

Methods

A survey instrument was adapted for use as an international assessment tool and then used to measure the availability of personnel, materials, equipment, medicines, and facility resources in nine Rwandan hospitals, including three referral centers.

Results

Forty-four percent of surveyed hospitals had a dedicated acute-care burn ward, while two-thirds had intensive care options. Relevant wound-care supplies were widely available, but gaps in the availability of critical pieces of equipment such as monitors, ventilators, infusion pumps, electrocautery, and dermatomes were discovered in many of the surveyed institutions, including referral hospitals. Early excision and grafting were not performed in any of the hospitals and there were no physicians with specialty training in burn care.

Conclusions

Whereas all surveyed hospitals were theoretically equipped to handle the initial resuscitation of burn patients, none of the hospitals were capable of delivering comprehensive care due to gaps in equipment, personnel, protocols, and training. Accordingly, steps to improve capacity to care for those with thermal injury should include training of physicians specialized in critical care and trauma surgery, as well as plastic and reconstructive surgery. Consideration should be given to creation of national referral centers specializing in burn care.  相似文献   
89.
目的:探讨脊髓神经元凋亡在鞘内注射血小板活化因子(PAF)诱发大鼠痛敏中的作用。方法鞘内置管成功的雄性 Sprague-Dawley 大鼠60只,随机分为2组:对照组,30只,鞘内注射人工脑脊液(arti-ficial cerebral spinal fluid,ACSF)10μl;PAF 组,30只,鞘内注射 PAF 10μg,溶解于10μl 人工脑脊液;分别于鞘内给药前1 d、给药后1、3、5、7、14 d 分别测定机械痛阈(PWMT)和热痛阈(PWTL)。取 L4-6脊髓,采用TUNEL 法观察脊髓神经元凋亡。结果鞘内注射血小板活化因子(PAF)可诱发出大鼠机械性触诱发痛和热痛觉过敏。PAF 组术后1 d 脊髓中开始有少量凋亡神经元出现,凋亡指数于术后3 d 开始迅速增加,术后5 d 达峰值,与对照组比较,有显著性差异(P 〈0.01)。结论鞘内注射 PAF 诱发大鼠触觉异常痛敏和热痛敏,脊髓神经元凋亡可能参与了鞘内注射 PAF 大鼠痛敏的形成。  相似文献   
90.

Background

The aim of the present study was to develop a rat model of colonic microperforation secondary to thermal injury for future studies to assess new treatments.

Methods

Twenty-four male Sprague–Dawley rats were used in this study. Hot biopsy forceps were used for all treatments. All lesions were created in proximal left colon using the soft coagulation setting. The power setting tested was 40 W, and the durations of monopolar soft coagulation application evaluated were 2, 3, and 4 s.

Results

In the acute phase, 48 h after thermal injury, durations of cautery of 2 and 3 s resulted in transmural necrosis, whereas with 4 s microperforation was obtained. In the late phase, 7 d after the damage, only duration of cautery of 4 s showed deep cautery effects, with signs of peritonitis.

Conclusions

We determined optimal power settings and duration of therapy in a rat model for producing electrocautery that involves transmural necrosis with microperforation.  相似文献   
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