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101.
肿胀法外超声吸脂术的组织学研究 总被引:7,自引:1,他引:6
目的 观察外超声能量作用于活体组织后的组织学变化,以探索其作用机制。方法 对3只家猪腹部两侧进行外超声与非超声比较,作用不同时间后在光镜和电镜下观察其皮肤组织全层的变化。结果 在外超声作用18min内,随着作用时间的延长,猪的皮下脂肪组织和生物大分子结构的破坏程度不断加重,脂肪组织中产生的空泡不断增大而皮肤组织及血管无明显变化。结论 外超声吸脂术可通过稳定的空泡效应选择性地使脂肪细胞结构发生不可逆的坏死性改变,这一改变与作用时间成正比。 相似文献
102.
Changes in cardiac output and in superior mesenteric arterial flow were followed with Doppler ultrasound techniques in five young, healthy persons for 2 h after ingestion of medium-sized (4 MJ), fluid meals containing either carbohydrate, protein, fat or water only. Measurements were carried out before meals and at regular post-meal intervals, during which mean arterial blood pressure was also followed. All energy-containing meals caused marked and gradually developing post-prandial increases in cardiac output as well as in superior mesenteric arterial flow. The maximum flow levels were reached in the course of 30–60 min and maintained until the observations ended after 2 h. The intake of water caused no such flow increases. There were considerable interpersonal variations in the size and in the speed of development of the flow increases after the three types of energy-containing meals. The flow-increasing effects of the three meal types were not significantly different, even if the most marked increases (median values about 1 1 min-1 for both cardiac output and superior mesenteric arterial flow) occurred after carbohydrate meals. The marked effects on circulation of the three food components were also revealed in the calculated, integrated amounts of ‘extra’ cardiac output and superior mesenteric arterial flow observed in the course of the 2 h following the meal. Values of more than 100 1 for such ‘extra’ flows were seen after carbohydrate meals. The marked ingestion-released increase in blood flow to the splanchnic organs is apparently partly met by an increase in cardiac output, and partly by some redistribution of flow, which benefits the digestive system. 相似文献
103.
三维超声技术及其在肝癌诊治中的应用 总被引:2,自引:0,他引:2
介绍三维超声成像技术的原理,讨论三维超声在肝癌的诊断性应用及在肝脏手术和介入中的治疗性应用。 相似文献
104.
聚焦超声治疗慢性宫颈炎500例临床分析 总被引:12,自引:0,他引:12
目的 探讨聚焦超声治疗宫颈炎的临床疗效.方法 收治慢性宫颈炎700例,分为聚焦超声治疗组(超生治疗组)500例,微波治疗对照组200例.观察其临床症状、体征及疗效.结果 超声治疗组中、重度宫颈炎的疗效明显高于微波对照组,差异有显著意义(P<0.05);两种方法治疗后,宫颈修复过程中阴道排液、出血等并发症的发生率,超声治疗组明显低于微波对照组,差异有显著意义(P<0.05).结论 聚焦超声治疗宫颈炎疗效确切,副作用及并发症少,是目前治疗宫颈炎的一种有效方法. 相似文献
105.
目的:探讨经腹超声及术中超声在胰腺结石诊断、治疗中的价值。材料和方法:对25例胰腺结石患者行经腹和术中超声检查。经腹超声主要观察胰管扩张程度,胰腺结石大小、位置,是否合并胆囊及胆道结石、胰腺假性囊肿等。术中超声观察是否有结石残留。结果:经腹超声显示25例患者主胰管扩张,胰腺实质增粗、增强。结石位于头部9例,位于全胰腺16例,伴有胆道梗阻征象13例,其中合并胆囊及胆道结石8例,并发胰腺假性囊肿3例,合并胰腺癌2例;术中超声形式显示6例未见残留结石,19例有残留结石,手术取出残留结石24枚。结论:经腹超声诊断主胰腺管结石敏感性较高,术中超声在判断残留结石及鉴别胰小管结石与胰腺实质钙化灶方面具有重要价值。 相似文献
106.
Background: The slitlamp can be used to estimate the anterior chamber depth (ACD). The length of a slit object is increased until the corneal and iris/lens images appear to just touch. Multiplying the just‐touching‐slit‐length (JTSL) by a conversion factor gives an estimate of the ACD as measured by ultrasonography. The purpose of this study was to determine if central corneal thickness (CCT) affects the accuracy of this technique. Methods: The ACD of 50 subjects was measured by A‐scan ultrasonography and estimated by the slitlamp technique. CCT was measured by ultrasonic pachometry. The refractive error was determined subjectively. Results: The average ultrasonographic ACD for all subjects was 3.32 ± 0.65 mm. The average JTSL was 2.46 ± 0.38 mm. The conversion ratio between the ultrasonographic ACD and the average JTSL was 1.35. The predicted ACD using the regression equation of JTSL on the ultrasound anterior chamber depth (USACD) was 3.32 ± 0.54 mm. The corresponding value using the regression equation of JTSL and CCT on USACD was exactly the same, that is, 3.32 ± 0.54 mm. Conclusion: Incorporation of CCT into a regression equation does not improve the accuracy of the Smith technique. 相似文献
107.
Margaret A. Paggiosi Aubrey Blumsohn Reinhard Barkmann Richard Eastell 《Journal of clinical densitometry》2005,8(4):436-444
It is unclear whether longitudinal change in phantom measurements bears any relation to the long-term in vivo instrument performance of quantitative ultrasound devices. Longitudinal quantitative ultrasound phantom data were obtained by measuring the manufacturer-provided phantom at ambient temperature and two different sets of Leeds phantoms at either ambient temperature or following a phantom temperature-control protocol. Measurements were performed using the Achilles Plus bone densitometer. Changes in longitudinal phantom data were compared to in vivo quantitative ultrasound data obtained from seven healthy, young volunteers. A cosinor model with linear trend and Hotelling's T2-test were used to quantify seasonal rhythms and long-term drift in quantitative ultrasound variables. Temperature effects and marked seasonal rhythms on quantitative ultrasound phantom measurements were evident but were far less apparent in vivo. Longitudinal precision of quantitative ultrasound variables was poorer for the manufacturer-provided phantom than for phantoms that were subjected to a temperature-control protocol or for healthy volunteers. This study has shown that longitudinal precision and longitudinal change differs between in vivo and phantom data. Longitudinal quantitative ultrasound measurements for monitoring change in skeletal status cannot, as yet, be properly controlled. 相似文献
108.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献
109.
A prototype electronic radial scan ultrasound endoscope has been developed by Olympus (Tokyo, Japan) for endoscopic ultrasound (EUS) study. The ultrasound view‐angle of this model is 360° vertical to the scope. Though the diameter of the scanner and the shaft of the scope is bigger than those of the present mechanical radial scan model, clinical manipulation of the new scope is the same as that of the present model. Image quality of the ultrasound picture demonstrated by the electronic radial model was as clear as those provided by the mechanical radial scan model. Ultrasound penetration was better and satisfactory because of less echoic reduction compared to the mechanical radial model. The newly developed electronic radial model can be evaluated as an ultrasound endoscope for the next generation. The advantage of this system is to facilitate the clinical use of color Doppler function and tissue harmonic imaging, and this system can be operated by the same monitor unit as a convex model of ultrasound endoscope. 相似文献
110.
In a prospective study we compared duplex-ultrasound characteristics of symptomatic internal carotid artery (ICA) stenoses with cranial computerized tomographic (CCT) findings in 82 patients suffering from completed or transient middle cerebral artery symptoms. The aim was to assess the pathogenic role of ICA plaque morphology and the potential embolic risk of ICA plaques. The degree of carotid stenosis was estimated by spectral analysis of the pulsed Doppler signal. The CCT findings were classified as being either normal, lacunar lesions, hemodynamically induced low-perfusion infarctions, or territorial embolic infarctions. According to their ultrasonic features we characterized the ICA plaque surface as smooth or irregular and their structure as homogeneous or heterogeneous. Plaques with an irregular surface and heterogeneous echogenicity dominated significantly in CCT-territorial infarctions (p < 0.01), whereas hemodynamically induced low-perfusion infarctions showed no relationship with any plaque characteristic. High degree ICA stenoses (> 50>%) dominated in both territorial infarctions and low-perfusion infarctions, as compared to ipsilateral normal CCT or lacunes (p < 0.05). Normal CCT and lacunar infarctions were associated with homogeneous and smooth plaques (both p < 0.05). We conclude that > 50% ICA stenoses can cause both hemodynamically induced low-perfusion infarctions as well as thromboembolic territorial infarctions, whereas ulcerated and heterogeneous plaques constitute a high risk factor for arterio-arterial embolic stroke. Furthermore, carotid ultrasound may help to estimate the clinical significance of carotid lesions. 相似文献