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11.
Y Miyamoto M Nakatani M Ida T Ishikawa N Okazawa M Ariizumi F Tsujimoto K Mizunuma Y Fukuda S Tada 《Journal of clinical ultrasound : JCU》1989,17(5):309-318
Ultrasonography was performed in 45 cases of gastric cancer. Specimens from all 45 cases of gastric cancer were subjects to ultrasonographic study by the water immersion method for comparison with histology. In 32 of these 45 cases in vivo ultrasonographic evaluation was performed prospectively. The overall accuracy rates for the diagnosis of the depth of cancerous invasion were almost 80% in both in vitro and in vivo studies. In vivo ultrasonographic findings agreed well with those from the specimen studies. Ultrasonography was considered to be useful in the diagnosis of gastric malignancies. 相似文献
12.
A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described. 相似文献
13.
Ultrasonography in the detection of cervical incompetency 总被引:2,自引:0,他引:2
Mario Podobnik Milan Buli Nikola Smiljanic Josip Bistri
ki 《Journal of clinical ultrasound : JCU》1988,16(6):383-391
In 80 pregnancies with clinical and ultrasonic signs of cervical incompetency, the length of the cervix and the thickness of the anterior wall of a lower uterine segment have been evaluated ultrasonically. We have also measured the width of the endocervical canal and studied the prolapse of fetal membranes (with fetal parts) into the endocervical canal. We evaluated these same parameters in 80 healthy pregnancies. The length of the cervix, the thickness of the anterior wall of a lower uterine segment, and the width of the endocervical canal were followed longitudinally in the patients from the 10th to the 36th gestation week. No statistically significant differences between age groups were found. In four age groups at risk for cervical incompetency, cervical lengths and wall thickness were significantly different (p less than 0.001) from those in comparable controls. Forty-five percent of the patients in the at-risk group, with cervical cerclage, delivered at 37.3 (range: 32 to 41) weeks and 6.25% of pregnancies ended in abortion when the amniotic membrane herniated into the cervical canal, with or without some part of the fetus. 相似文献
14.
Performance of the polymer- and oxide-supported triphase catalysts and effect of ultrasound on their stabilities 总被引:1,自引:0,他引:1
Hsieh-Ting Chung Hung-Shan Weng 《Journal of the Chinese Institute of Chemical Engineers》2008,39(5):449-455
In this study, several trialkylamines were immobilized on chloromethylated polystyrene (CMPS), silica gel, and alumina to prepare triphase catalysts for catalyzing the etherification reaction of allyl bromide (the organic reactant) and sodium phenolate (the aqueous reactant). The reactor was agitated mechanically or with the aid of ultrasonic vibration. Performances of the prepared catalysts were compared, and the effect of imposing ultrasound was investigated based on the activity, selectivity, and stability of the catalyst. Experimental results show that tri-n-propylamine is the best active species when CMPS is used as the support, while tri-n-butylamine is the best when SiO2 and Al2O3 are employed as the supports. The CMPS-supported catalyst is far better than the SiO2- and Al2O3-supported catalysts in activity and selectivity but not in stability. Imposing the ultrasound can effectively increase the reaction rate. Mechanical agitation at a low speed with the imposition of ultrasonic vibration not only results in a conversion slightly higher than the case with a high mechanical agitation speed without ultrasonic vibration, but also gives a constant stability for the CMPS-supported catalyst. 相似文献
15.
Graham P. Gavin Garrett B. McGuinness Finbar Dolan M.S.J. Hashmi 《International Journal of Mechanical Sciences》2007,49(3):298-305
Therapeutic ultrasound angioplasty has been investigated, clinically, by a number of researchers and represents a potentially promising therapy for the treatment of atherosclerotic lesions. To date, there has been no detailed analysis of the effect of mechanical design parameters, such as wire geometry or damping characteristics, on wire waveguide performance. An apparatus capable of delivering therapeutic ultrasound down small diameter nickel–titanium (NiTi) wire waveguides is described. The output peak-to-peak (p–p) displacements at the distal tip of a 1.0 mm diameter waveguide were measured experimentally, by means of an optical microscope and image analysis software. The output was measured for a range of waveguide lengths from 118 to 303 mm. Wire waveguide distal tip displacements as high as 98 μm (p–p) at 23.5 kHz were measured. For the range of lengths tested, the experimental measurements show the critical relationship between the length of the waveguide and the output distal tip displacements. A finite element model that can predict the resonant frequencies and distal tip displacements of various wire waveguide geometries and configurations, including the effect of damping, is presented. This numerical model has been validated against the experimental displacement data obtained. This will be a valuable design tool for ensuring the safety and effectiveness of therapeutic ultrasound angioplasty procedures. 相似文献
16.
Ultrasonographic (US), computed tomographic (CT), and magnetic resonance imaging (MRI) findings of a patient suffering from an amebic abscess of the liver complicated by a bronchohepatic fistula are presented. Subsequent to US, CT provided the specific diagnosis. Multiplanar MRI was valuable to directly visualize the secondary diaphragmatic rupture and the bronchohepatic fistula. 相似文献
17.
18.
Recycling of rubber-based materials is of increasing industrial environmental importance. In order to characterize the effect of ultrasound on polymer networks, nuclear magnetic resonance (NMR) relaxation and pulsed-gradient diffusion measurements were made at 70.5 °C in polyurethane rubber (PUR) and foam after subsequent treatment by intense ultrasound. The proton transverse relaxation decay was analyzed in terms of molecular and segmental mobilities of all motional species, a chemical and physical network as well as diffusing sol. The diffusivity spectrum, measurable in foams, reflected the changing molecular weight distribution of low-molecular weight sol and oligomers. It was observed that the effect of ultrasound was less pronounced in PUR than rubbers like SBR, PDMS and BR owing to its low degree of unsaturation. The investigation on the foams is the first of its kind to be reported. 相似文献
19.
超声波气升式反应器内声压的测定 总被引:2,自引:0,他引:2
测定了在空气—水和空气—羧甲基纤维素水溶液体系中 (羧甲基纤维素含量 :2g/L)超声波气升式反应器声压随轴向位置、表观气速、黏度和超声电功率的变化。测定结果表明 ,小气速下声压在气升式反应器内的轴向分布与离开超声探头的距离有关 ,距离越远 ,声压越小 ;与气速的大小有关 ,气速越大 ,声压越小 ;与液体的黏度有关 ,黏度越大 ,声压越小 ;超声电功率越大 ,声压越大。 相似文献
20.