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排序方式: 共有5355条查询结果,搜索用时 265 毫秒
81.
目的:探讨剪切波弹性成像(shear wave elastography,SWE)与细针穿刺洗脱液甲状腺球蛋白(fine-needle aspiration washout thyroglobulin,FNA-Tg)对甲状腺乳头状癌侧颈部淋巴结转移的诊断价值。方法:回顾性分析159例经病理证实为甲状腺乳头状癌(papillary thyroid carcinoma,PTC)的患者资料,对颈部211枚可疑淋巴结进行常规超声、SWE参数平均值(Emean)、FNA-Tg检查,以术后病理结果为金标准,比较各检测方法的诊断效能。结果:(1)SWE Emean转移组[(50.96±27.66) kPa]高于非转移组[(32.20±17.34) kPa],差异有统计学意义(t=8.761,P<0.01)。受试者工作特征(receiver operating characteristic,ROC)曲线分析表明,SWE Emean最佳诊断阈值为40.42 kPa时对PTC颈部淋巴结转移预测价值较高,曲线下面积(area under... 相似文献
82.
目的:评估团块状灰度变化能否减轻子宫良性疾病聚焦超声消融术中的远场不良反应。方法:开展单中心回顾性临床观察研究,纳入重庆医科大学附属第二医院行聚焦超声消融术的40例子宫良性疾病。比较团块状灰度变化出现前后,在相同能量水平(最小不可耐受能量)下,术中即刻骶尾部或臀部疼痛、放射痛、会阴部痛、肛门胀痛的发生率及不良反应程度。结果:在相同能量水平(最小不可耐受能量)下,团块状灰度变化出现后术中即刻骶尾部或臀部疼痛、放射痛、会阴部痛、肛门胀痛的发生率及不良反应程度明显低于团块状灰度变化出现前(P<0.05)。结论:团块状灰度变化能减轻子宫良性疾病聚焦超声消融术中的远场不良反应。 相似文献
83.
腹腔镜超声刀在妇科恶性肿瘤淋巴结切除术中的应用 总被引:7,自引:0,他引:7
目的:探讨在妇科恶性肿瘤腹腔镜淋巴结切除术中使用超声刀切割,止血的效果。方法:应用超声刀进行妇科恶性肿瘤腔镜盆腔及腹主动脉周围淋巴结切除术共13例,其中子宫颈癌10例,子宫内膜癌3例,手术步骤包括经阴道腹腔镜辅助广泛全子宫切除,盆腔及腹主动脉周围淋巴结切除和卵巢动静脉高位结扎,并与同期应用电刀切割和止血的相同术式进行比较。结果:使用超声刀较电刀切割和止血术中出血量明显减少(P<0.05),手术时间显著缩短(P<0.05),无术中及术后并发症。结论:腹腔镜下应用超声刀切割和止血具有手术时间短,止血效果更佳,对周围组织无损伤且并发症少等优点。 相似文献
84.
蝶窦囊肿诊治47例分析 总被引:5,自引:1,他引:4
目的:提高对蝶窦囊肿的认识,以利于其诊断和治疗,方法:回顾性分析蝶窦囊肿47例,总结其发病趋势、临床表现,影像学特征及治疗效果。结果:蝶窦囊肿最主要的临床症状为头痛,约占64%;其次为眼部症状,再次为鼻部症状。蝶窦囊肿最易易及视神经,影响者视力,早期手术有利于神经力的恢复。鼻内窥镜下蝶窦囊肿摘除了术有损伤小,出血少,痛苦轻,手术时间短、安全,术后恢复快等优点。结论:CT、MRI和鼻内窥镜的应用,提 相似文献
85.
McCallion Orla N. M. Taylor Kevin M. G. Thomas Marian Taylor Anthony J. 《Pharmaceutical research》1995,12(11):1682-1688
Purpose. Empirical formulae relate the mean size of primary droplets from jet and ultrasonic nebulizers to a fluid's physicochemical properties. Although the size selective filtering effects of baffling and evaporation may modify the secondary aerosol produced, this research sought to evaluate whether viscosity and surface tension of nebulized fluids influenced the aerosol's size and output characteristics.
Methods. Fluid systems of different surface tension and viscosity (glycerol and propylene glycol solutions [10–50% (v/v)] and a range of silicone fluids [200/0.65 cs– l00cs]) were nebulized in three jet and two ultrasonic nebulizers. Secondary aerosol characteristics were measured with a Malvern 2600C laser diffraction sizer and the nebulization times, residual volumes and percentage outputs were determined.
Results. While the droplet size appeared to be inversely proportional to viscosity for jet nebulizers, it was directly proportional to viscosity for ultrasonic nebulizers. Although fluid systems with lower surface tensions generally produced slightly smaller MMDs, the relationship between surface tension and droplet size was complex. The more viscous fluids required longer nebulization times and were associated with increased residual amounts (lower outputs). The ultrasonic nebulizers did not effectively, and were on occasion unable to, nebulize the more viscous fluids.
Conclusions. It follows that there are cut-off values for viscosity and/or surface tension above or below which ultrasonic devices fail to operate. Moreover, jet nebulizers generated an aerosol with an optimum respirable output from median-viscosity fluids. 相似文献
86.
87.
陈玉明 《南京中医药大学学报》1999,15(1):56-57
本文对83例患者盆腔囊性肿块超声诊断结果与手术及病理检查进行对比,提高了超声诊断的准确性。同时结合中医辨证分型拟找寻出中医分型与超声诊断的内在联系,以提高中医诊疗水平 相似文献
88.
Implementation of percutaneous dilation tracheotomy – value of preincisional ultrasonic examination?
BACKGROUND: In this observational study we have evaluated the implementation of percutaneous dilation tracheotomy (PDT), using the forceps dilation technique (Portex) in a multidisciplinary ICU. METHODS: We included a preincisional ultrasonic evaluation of the neck in order to visualise the isthmus glandula thyroidea and major vessels. The observational period comprised one year. PDT was performed in 28 patients. RESULTS: Implementation of PDT was uneventful. Duration of insertion was 10 min (4-40 min). Total time of tracheostomy was 8 days (1-65 days). In nine cases, the proximal end of the isthmus was overlying the space between the 1st and 2nd tracheal ring, which was considered the optimal insertion site. This resulted in seven cases of insertion between the cricoidea and the 1st tracheal ring and in two cases in a more distal insertion. Nineteen tracheotomies were performed in the interstice between the 1st and 2nd tracheal ring. In nine patients, major vessels were overlying the trachea. In none of the patients did this information result in an altered insertion site. Two cases of minor bleeding were observed; both stopped upon compression. In two patients the primary tube size (8.0) was too big and a smaller tube had to be inserted. In one patient the tube was maladapted to the stoma and had to be interchanged with an ordinary tracheostomial tube on the 5th day of tracheostomy. CONCLUSION: Based on the experience gathered in this study and information from the literature, we have abandoned the routine use of ultrasonic examination of the neck prior to PDT. In order to achieve and maintain routine, we suggest that the procedure is performed by a restricted number of doctors. 相似文献
89.
P. Hazarika D. R. Nayak K. Pujary L. Rao 《Indian journal of otolaryngology and head and neck surgery》2003,55(1):34-38
Sckhwannoma is a benign tumor arising from the Schwann cells of nerve sheath.Through they arise more commonly in the head
and neck than other regions, a through search in the liturature including medline revealed only about 47 reported cases of
schwannoma in the paranasal sinuses of which the maxillary sinus involvement is more common. We report three cases of schwannoma
arising from unusual sites in the paranasal sinuses with different modes of presttation each requiring a specific approach
for surgical excision Transnasal endoscopic approach in combination with vonventional approaches is of immense value in the
surgical management of these benign lessions of the paranasal sinuses. 相似文献
90.
超声法提取绞股蓝总皂甙的工艺研究 总被引:32,自引:2,他引:32
本实验证明,超声法可以提高绞股蓝总皂甙的提取率,最佳提取工艺为超声高频提取3次,每次80min,得率为1.226%。 相似文献