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1.
The dispersion into water of nanocapsules bearing a highly hydrophobic fluorinated internal lining yielded encapsulated air nanobubbles. These bubbles, like their micrometer‐sized counterparts (microbubbles), effectively reflected ultrasound. More importantly, the nanobubbles survived under ultrasonication 100‐times longer than a commercial microbubble sample that is currently in clinical use. We justify this unprecedented stability theoretically. These nanobubbles, owing to their small size and potential ability to permeate the capillary networks of tissues, may expand the applications of microbubbles in diagnostic ultrasonography and find new applications in ultrasound‐regulated drug delivery.  相似文献   
2.
目的探讨超声内镜对于应用ESD治疗上消化道隆起性病变的疗效及安全性。方法20例上消化道黏膜局限性隆起病变,先行超声内镜检查,再采用ESD进行治疗,比较术前超声内镜诊断与内镜治疗术后病理结果的一致性,记录手术耗时、整块切除率、并发症发生率及局部残留复发率。结果食管病变6例,其中早癌及高级别上皮内瘤变各1例,平滑肌瘤4例;胃内病变14例,其中胃早癌及高级别上皮内瘤变各3例,异位胰腺1例,间质瘤7例。术前EUS诊断与术后病理结果的一致性为100%。手术时间16~100(32.8±15.7)min;整块切除率85%,出血率为20%,穿孔率10%,术后随访1~12个月,无残留与复发。结论超声内镜对消化道黏膜隆起性病变诊断准确率高,超声内镜辅助下ESD治疗上消化道隆起性病变安全有效。  相似文献   
3.
A new class of multifunctional nanoparticles that combine properties of polymeric drug carriers, ultrasound imaging contrast agents, and enhancers of ultrasound-mediated drug delivery has been developed. At room temperature, the developed systems comprise perfluorocarbon nanodroplets stabilized by the walls made of biodegradable block copolymers. Upon heating to physiological temperatures, the nanodroplets convert into nano/microbubbles. The phase state of the systems and bubble size may be controlled by the copolymer/perfluorocarbon volume ratio. Upon intravenous injections, a long-lasting, strong and selective ultrasound contrast is observed in the tumor volume indicating nanobubble extravasation through the defective tumor microvasculature, suggesting their coalescence into larger, highly echogenic microbubbles in the tumor tissue. Under the action of tumor-directed ultrasound, microbubbles cavitate and collapse resulting in a release of the encapsulated drug and dramatically enhanced intracellular drug uptake by the tumor cells. This effect is tumor-selective; no accumulation of echogenic microbubbles is observed in other organs. Effective chemotherapy of the MDA MB231 breast cancer tumors has been achieved using this technique.  相似文献   
4.
Ultrasonography is a convenient and widely used technique to look into the longitudinal muscle motion as it is radiation-free and real-time. The motion of localized parts of the muscle, disclosed by ultrasonography, spatially reflects contraction activities of the corresponding muscles. However, little attention was paid to the estimation of longitudinal muscle motion, especially towards estimation of dense deformation field at different depths under the skin. Yet fewer studies on the visualization of such muscle motion or further clinical applications were reported in the literature. A primal–dual algorithm was used to estimate the motion of gastrocnemius muscle (GM) in longitudinal direction in this study. To provide insights into the rules of longitudinal muscle motion, we proposed a novel framework including motion estimation, visualization and quantitative analysis to interpret synchronous activities of collaborating muscles with spatial details. The proposed methods were evaluated on ultrasound image sequences, captured at a rate of 25 frames per second from eight healthy subjects. In order to estimate and visualize the GM motion in longitudinal direction, each subject was asked to perform isometric plantar flexion twice. Preliminary results show that the proposed visualization methods provide both spatial and temporal details and they are helpful to study muscle contractions. One of the proposed quantitative measures was also tested on a patient with unilateral limb dysfunction caused by cerebral infarction. The measure revealed distinct patterns between the normal and the dysfunctional lower limb. The proposed framework and its associated quantitative measures could potentially be used to complement electromyography (EMG) and torque signals in functional assessment of skeletal muscles.  相似文献   
5.
本文探讨了桥本氏甲状腺炎合并甲状腺乳头状微小癌患者的超声特点与临床参数的相关性。选择2010年1月~2018年12月我院收治的桥本氏甲状腺炎合并甲状腺乳头状微小癌患者75例作为研究组,单纯桥本甲状腺炎患者696例作为对照组,分析了两组患者的临床病理特征、二维超声图像特征及内部血流图像特征。结果显示,两组平均年龄、肿块直径、病灶数量、甲状腺结构、形态、晕圈比较无统计学差异(P>0.05);研究组的性别构成、病灶钙化情况、内部回声情况、内部血流情况与对照组有统计学差异(P<0.05)。多因素Logistic回归分析显示,女性、微钙化、边缘回声不清晰、内部极低回声、内部无血流是桥本氏甲状腺炎合并甲状腺乳头状微小癌的危险因素(P<0.05)。说明超声能够对桥本氏甲状腺炎合并甲状腺乳头状微小癌进行有效诊断。  相似文献   
6.
本文通过高频超声检查分析了肩袖病变与肱二头肌长头肌腱(long head of the biceps brachii tendon,LHBT)病变的临床特点及相关性.文中对32例肩关节镜手术患者的术前肩关节超声检查结果与肩关节镜手术结果进行了 一致性检验.按照不同肩袖病变类型对患者进行分组,对组间LHBT病变类型的差异...  相似文献   
7.
本文对药物流产后宫内残留物的腹部超声检测及其对清宫术时机的指导作用进行了探讨。研究对象为2017年4月~2018年10月我院妇科收治的164例药物流产后宫内组织残留患者,所有患者均行经腹彩色多普勒超声检查,观察宫腔内异常回声团和宫内血流信号及频谱,并记录患者治疗情况和病理结果。依据患者保守治疗成功或转归清宫术分为成功组和转归组,采用多因素Logistic回归方程分析对保守治疗失败转归清宫术有影响的因素。结果显示,164例患者中,79例(48.17%)患者超声检查显示存在滋养血流,其中47例(59.49%)患者采取了清宫术治疗,其余32例(40.51%)患者保守治疗失败转归清宫术治疗;85例(51.83%)患者超声检查显示无滋养血流,其中73例(85.88%)采取保守治疗成功,其余12例(14.12%)患者保守治疗失败转归清宫术;成功组(n=73)和转归组(n=44)患者在就诊时阴道出血时间、阴道出血持续时间、流产次数、宫内残留物大小、滋养血流信号检出率等方面的比较,差异均具有统计学意义(P<0.05);多因素Logistic回归方程分析结果显示,就诊时阴道出血时间、残留物大小、流产次数、超声检查存在滋养血流均为保守治疗转归清宫术的独立影响因素(P<0.05)。本文结果证实,腹部超声检测显示宫腔内异常回声团块存在滋养血流信号,可作为药物流产不全患者行清宫术治疗的手术指征,有利于改善患者预后。  相似文献   
8.
目的探讨彩色多普勒能量图(CDE)、彩色多普勒超声(CDUS)检查评估活动期强直性脊柱炎(AS)患者骶髂关节炎的应用价值。方法对36例活动期AS患者的72个骶髂关节进行MRI检查,筛选出存在活动性炎症的63个骶髂关节(病例组)及25例健康志愿者的50个骶髂关节(对照组)作超声检测,对比血流显示率、血流丰富程度(半定量分级)及血流阻力指数(RI),并对治疗后病情缓解的31例AS患者的54个骶髂关节行CDE、CDUS检查,对比活动组及病情缓解组的血流显示率、血流丰富程度及血流RI。结果病例组骶髂关节内部或周边血流显示率(90.5%)较对照组(52.0%)高,两组间差异有统计学意义(P=0.000);病例组以2~3级多血流为主,而对照组以0~1级少血流为主,病例组与对照组间骶髂关节血流丰富程度的差异有统计学意义(P=0.000);病例组平均动脉血流RI为0.57±0.07,较对照组的0.78±0.11低,两组间差异有统计学意义(P=0.000)。活动组的平均动脉RI 0.57±0.08较病情缓解组0.69±0.09低,两组间差异有统计学意义(P=0.000);而活动组与病情缓解组的骶髂关节内部或周边血流显示率及血流丰富程度差异均无统计学意义(P=0.086、0.052)。结论彩色超声可显示骶髂关节异常血流信号,尤其是低阻血流信号为诊断AS患者骶髂关节炎并评估其活动性提供了重要的参考依据。  相似文献   
9.
选取2011年6月~2017年6月于我院就诊的经病理学检查明确确诊为肝血管平滑肌脂肪瘤(HAML)的43例患者,通过对纳入患者的49个HAML病灶的超声造影(CEUS)及增强CT(CECT)的影像学表现及术前诊断结果进行分析,探讨CEUS联合CECT在诊断不典型HAML中的临床价值。结果显示,HAML在女性中的发病率显著高于男性(P<0.001),且HAML多为单发病灶(P<0.001)。术前经CECT准确诊断HAML者有34.69%,经CEUS准确诊断HAML者有57.14%,二者联合准确诊断HAML者有77.55%,联合诊断的准确性显著高于单独应用CECT或CEUS(P<0.05)。HAML在CECT和CEUS上的表现具有一定的特征性,二者联合应用可以提高HAML诊断正确率。  相似文献   
10.
The subject matter of this paper concerns advanced techniques of imaging used in diagnosis and minimally invasive procedures applied in non-operable cases of the digestive tract tumour therapy. The role of optical techniques in current medical imaging is significant. Optical properties of transilluminated or illuminated tissues and organs depend on strong light absorption and scattering. Numerous issues related to the result interpretation still remain unsolved. Effectiveness and precision can be especially improved when some combined methods of imaging are used. Videoendoscopy imaging, X-ray imaging, and endoscopic ultrasound imaging are three complementary methods applied during the interventions described in this work. All interventions have concerned with the upper part of the digestive tract. Especially, interdisciplinary issues of combined medical imaging are presented using some examples of a modern approach to imaging of esophagus and biliary stenting. The selected examples of effects obtained during interventions assisted by combined imaging of the operation site are presented. The operator can have great control over the appearance of desirable effects as well as undesirable complications in order to work comfortably and safe.  相似文献   
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