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51.
目的为了提高对异位妊娠的诊断技术。方法选择在我院经手术病理证实的异位妊娠249例住院患者行2DB超和CDFI的声像图特征进行分析。结果2D超声声像图特征在249例异位妊娠中内膜增厚223例,厚度为4—8mm/2;宫内假环状孕囊28例,大小为4.12mm;宫外探及孕囊178例,大小为8-48mm;盆腔混合性包块28例,大小为40.80mm:伴有黄体囊肿的123例,存活宫外孕3例,可显示原始心管搏动;CDFI声像图特征为宫外孕急性破裂的患者显示肿块及周围组织的彩色血流信号增多,动脉频谱血流速度增快,RI降低。结论超声检查对妇产科急诊有显著性作用,可直接指导临床明确诊断,选定治疗方案。  相似文献   
52.
Pulsed ultrasonic Doppler velocimetry (20 MHz) (PUDVM) has evolved considerably in the last 10 years. Engineering development has resulted in a computer-controlled vessel-scanning instrument whose backscattered frequency shift spectra are analyzed using fast Fourier transforms (FFT). Benchtop and theoretic studies indicate accurate (error less than 5%) velocity and volumetric flow rate measurements in vessels with a lumen diameter as small as 1.2 mm. Clinical application of the PUDVM has provided transcutaneous measurements of blood flow variables in normal human digital arteries. Experimental application to arteries 1.0-1.5 mm has provided information on the hemodynamic effects of topical vasodilators, standard microarteriorrhaphy, variations in microvascular technique, interpositional grafts, and early wound repair. With improving computer capabilities and technical modifications, the PUDVM will be an increasingly important tool in clinical and experimental microsurgery.  相似文献   
53.
A case of solitary extramedullary plasmacytoma of the testis is presented demonstrating the appearances on ultrasound. The clinical implications of this diagnosis are discussed.  相似文献   
54.
超声引导下注射皮质类固醇治疗狭窄性腱鞘炎   总被引:1,自引:0,他引:1  
目的 探讨超声引导下注射皮质类固醇治疗狭窄性腱鞘炎的方法及效果。方法 38例狭窄性腱鞘炎患者,按药物注射方法的不同随机分成2组。治疗组(21例)在10-MHz超声引导下向腱鞘内腱周间隙内穿刺注射醋酸强的松龙0.6 ml,对照组(17例)采用闭合穿刺法注射等量药物。注射前及随访时(注射后3周)测定疼痛强度视觉类比评分(Visual analogue score,VAS)。结果 随访时疼痛消失率治疗组为81%、对照组为53%,VAS下降值治疗组为[(6.8±1.9)x±s,下同]对照组为(5.1±3.0)。结论超声引导下将针尖穿刺于腱鞘内腱周间隙的操作简单、准确并可实时观察药物的分布,是治疗狭窄性腱鞘炎的较好方法。  相似文献   
55.
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   
56.
Osteoprotegerin (OPG), a secreted member of the tumor necrosis factor receptor family, is a potent inhibitor of osteoclast activation and differentiation. In animal models OPG prevents bone loss, and in humans bone resorption can be reduced by injections of OPG. OPG may also play a role in cardiovascular disease since mice lacking the OPG gene display arterial calcification. In a screening effort of the OPG gene, we recently discovered a single nucleotide polymorphism in the promoter region of OPG (T950C), and reported an association with vascular morphology and function in 59 healthy individuals. Due to the pronounced effect of OPG on bone turnover, the present study was conducted to investigate whether OPG polymorphisms are also associated with bone mineral density or with fracture. The relationship between single nucleotide polymorphisms in the promoter region of OPG (T950C) and the first intron (C1217T), and bone mineral density, measured by DXA in the hip or spine or ultrasound of the heel, was investigated in the Malmö OPRA-study of 1044 women, all 75 years old. The possible relation to fracture incidence was also analyzed. Among the 858 and 864 individuals respectively, genotyped, no significant associations between the investigated single nucleotide polymorphisms and bone mineral density measurements (T950C P = 0.50–0.64, C1217T P = 0.51–1.00), quantitative ultrasound measurements of the calcaneus, or fractures (T950C P = 0.61–0.66, C1217T P = 0.14–0.33) were found. Thus, our results show that polymorphisms in the OPG gene, one of which has previously been found to be associated with cardiovascular morphology and function, are not associated with bone mineral density in elderly Swedish women.  相似文献   
57.
A number of studies have shown that ultrasound has an advantage over physical examination in the diagnosis of acute appendicitis. Most of these studies were conducted by experts in the field of ultrasonography. In this study the influence of experience on the results of the sonography of actue appendicitis were evaluated. All 203 patients admitted to our unit between December 1990 and December 1992 were examined physically and sonographically by a team of surgeons consisting of one experienced sonographer and six inexperienced surgical trainees. Laparotomy was performed in 136 patients (46%). Appendicitis was demonstrated histologically in 119 cases (39.4%). Initial clinical findings were positive in 87 (28.8%). Sonography was positive in 119 patients (39.4%). The 163 patients not operated on demonstrated other pathology on ultrasound in 60 cases (19.9%). The rate of negative laparotomies amounted to 7.2% in our study. Sensitivity and specificity for the sonographic diagnosis were 92% and 95%, respectively. They were only 81% and 80% for physical examination. Overall accuracy was 92% for sonography. Sensitivity and specificity for the inexperienced surgeons were 87% and 93%, respectively, while the experienced surgeon reached values of 97% and 98%, respectively. The results of both groups are comparable with values in the literature, suggesting that ultrasound evaluation of appendicitis is not a diagnostic tool limited to a few experienced sonographers.  相似文献   
58.
Ultrasonography in the detection of cervical incompetency   总被引:2,自引:0,他引:2  
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   
59.
The enhancement of fluorescence emission from the tryptophan residue of glucagon, the quenching of that emission with acrylamide and with 5-doxyl and 16-doxyl stearic acid, circular dichroism spectra, the release of 6-carboxytluorescein, and polarized infrared attenuated total reflection (IR-ATR) spectra were used to study the interaction of glucagon with intact lipid vesicles and flat bilayers. Dimyristoylphosphatidylcholine bound the peptide only below the main transition temperature, thus confirming earlier results of Epand et al. (1977). However, the peptide is also bound by vesicles of unsaturated lipids above their transition temperature, suggesting an influence of lipid area on the binding process. Circular dichroism showed that binding to such vesicles also increases the helix content of glucagon. The IR-ATR study and a comparison with dynorphin-A-(I-13)-tridecapeptide revealed profound differences in orientation of the two peptides. The dichroic ratios and the derived order parameters indicated an isotropic orientation of the helical segments of glucagon, but did not exclude a principal orientation of the molecules lying flat on the nienibrane surface. In contrast, the axis of the dynorphin helix is clearly oriented normal to the interface. The two peptides also differ in their rates of 6-carboxyfluorescein release, suggesting a deeper penetration of the primary amphiphilic helix of dynorphin A-(I-13) than of the secondary amphiphilic helix of glucagon.  相似文献   
60.
目的:探讨B超对异位妊娠的诊断价值。方法:对2004年1月~2009年1月的86例异位妊娠患者,采用超声诊断仪进行检查、分析。结果:超声检查的86例异位妊娠患者,诊断符合84例,确诊率为97.6%,误诊2例,误诊率为2.4%。结论:超声检查有着无创性、可重复性等不可比拟的优越性,为异位妊娠患者的诊断及治疗提供了可靠的依据。  相似文献   
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