基于活动轮廓模型的序列超声图像的心内壁运动跟踪方法

提出一种对心脏序列超声图像中的心内壁进行运动跟踪的方法,采用活动轮廓模型将前一帧图像中snake的停留位置作为当前帧snake的初始位置,选择适当的能量函数,使能量函数最小snake变形得到当前时刻的心内壁轮廓,实验结果论证了该算法的可行性。     

Changes in Triphasic Mechanical Properties of Proteoglycan-Depleted Articular Cartilage Extracted from Osmotic Swelling Behavior Monitored Using High-Frequency Ultrasound

This study aims to obtain osmosis-induced swelling strains of normal and proteoglycan (PG) depleted articular cartilage using an ultrasound system and to investigate the changes in its mechanical properties due to the PG depletion using a layered triphasic model. The swelling strains of 20 cylindrical cartilage-bone samples collected from different bovine patellae were induced by decreasing the concentration of bath saline and monitored by the ultrasound system. The samples were subsequently digested by a trypsin solution for approximately 20 min to deplete proteoglycans, and the swelling behaviors of the digested samples were measured again. The bi-layered triphasic model proposed in our previous study (Wang et al., J Biomech Eng-Trans ASME 2007; 129: 413-422) was used to predict the layered aggregate modulus Hafrom the data of depth-dependent swelling strain, fixed charge density and water content. It was found that the region near the bone, for the normal specimens, had a significantly higher aggregate modulus (Ha₁= 20.6±18.2 MPa) in comparison with the middle zone and the surface layer (Ha₂= 7.8±14.5 MPa and Ha₃= 3.6±3.2 MPa, respectively) (p < 0.001). The normalized thickness of the deep layer h₁ was 0.68±0.20. After the trypsin digestion, the parametric values decreased to Ha₁ = 13.6±9.6 MPa, Ha₂ = 6.7±11.5 MPa, Ha₃ = 2.7±3.2 MPa, and h₁ = 0.57±0.28. Other models were also used to analyze data and the results were compared. This study showed that high-frequency ultrasound measurement combined with the triphasic modeling was capable of nondestructively quantifying the alterations in the layered mechanical properties of the proteoglycan-depleted articular cartilage.     

US-FNAB 在甲状腺良恶性结节鉴别诊断中的应用价值

目的:探讨超声引导下甲状腺穿刺活检(US-FNAB)对甲状腺良恶性结节的诊断价值。方法:本研究选取了60例已做过甲状腺结节手术的患者,入院后先行常规超声(US)检查后行超声引导下甲状腺穿刺活检(US-FNAB)通过观察并记录良恶性结节诊断结果:,诊断结果:符合率及诊断结果:符合率与结节大小的关系,评价US-FNAB对甲状腺良恶性结节的诊断价值。结果:常规超声诊断出恶性结节4例,良性结节33例;超声引导下细针穿刺活检诊断出恶性结节8例,良性结节40例。US组中,15例误诊,8例漏诊中,诊断符合率为61.7%。US-FNAB组中,4例误诊,漏诊2例,诊断符合率80.0%。经统计学分析,US-FNAB组诊断符合率明显高于US组(P0.05),US组与US-FNAB组在各结节直径的患者分布上相比差异无统计学意义(P0.05)。两组组内各结节直径的患者分布上相比差异也无统计学意义(P0.05)。US-FNAB组中,随着结节直径增大,诊断符合率略有降低。对直径10mm的甲状腺结节诊断率达100%。结论:US-FNBA对甲状腺良恶性结节具有较高的诊断准确性,诊断准确性受结节大小影响较小,对直径较小的甲状腺结节检出率较高。     

Efficient gene transfer into silkworm larval tissues by a combination of sonoporation and lipofection

Sonoporation (ultrasound treatment) provides a new and attractive nonviral way of in vivo gene transfer. To access the applicability of this method to the silkworm, Bombyx mori, we have compared the efficiencies of gene transfer by means of lipofection (using an appropriate agent, PDD111), sonoporation (ditto, FluoroGene), and lipofection followed by sonoporation. By these methods, a luciferase expression plasmid was found to be markedly transferred into the haemocoel of newly ecdysed fifth instar silkworm larvae, and also into other tissues although with lower rates compared with the haemocoel. In terms of luciferase activity, the efficiencies of transgene by lipofection plus sonoporation were approximately 6 (hemocytes), 20 (silk glands), 8 (mid-gut), 38 (fat body), 10 (Malpighian tubules), 33 (ovaries), and 16 (testes) times as high as those by lipofection or sonoporation alone. These results demonstrated that the present method is useful to introduce the exogenous DNA into insect organs in vivo.     

超声胃镜小探头对上消化道黏膜下病变的诊断价值探讨

目的:探讨超声胃镜小探头对上消化道黏膜下病变的诊断价值.方法:使用超声胃镜小探头对我院2010年6月-2011年12月62例经电子胃镜检查的上消化道黏膜下病变患者进行检查,对病变的浸润范围与性质进行分析,结果与术后病理进行对比.结果:良性间质瘤43例,占69.35％,恶性间质瘤6例,占9.68％,异位胰腺5例,占8.06％,囊肿6例,占9.68％,脂肪瘤与静脉曲张各1例,占1.61％.所有结果均经病理检查证实,符合率100％,结果具有代表性(P＜0.05).结论:使用超声胃镜小探头能清楚显示上消化道各层管壁结构,确定上消化道黏膜下病变的性质,提高诊断率,具有极高的临床价值,可作为上消化道黏膜下病变的诊断方法在临床推广应用.     

Robust spectral estimation for speed of sound with phase shift correction applied online in yeast fermentation processes

Ultrasound techniques are well suited to provide real‐time characterization of bioprocesses in non‐invasive, non‐contact, and non‐destructive low‐power consumption measurements. In this paper, a spectral analysis method was proposed to estimate time of flight (TOF) between the propagated echoes, and its corresponding speed of sound (USV). Instantaneous power spectrum distribution was used for accurate detection of echo start times, and phase shift distribution for correcting the involved phase shifts. The method was validated by reference USV for pure water at 9–30.8°C, presenting a maximum error of 0.22%, which is less than that produced by the crosscorrelation method. Sensitivity analyses indicated a precision of 6.4 × 10^?3% over 50 repeated experiments, and 0.11% over two different configurations. The method was competently implemented online in a yeast fermentation process, and the calculated USV was combined with temperature and nine signal features in an artificial neural network. The network was designed by back propagation algorithm to estimate the instantaneous density of the fermentation mixture, producing a maximum error of 0.95%.     

Estrus induction in white rhinoceros (Ceratotherium simum)

The estrous cycle length in the white rhinoceros (Ceratotherium simum) is either 4 or 10 wk. The cause(s) for this variation as well as the poor fertility rate in captivity remains under debate in this species. Most captive adult white rhinoceros undergo long anovulatory periods without luteal activity which are considered a major reason for their low reproductive rate. In this study, the synthetic progestin chlormadinone acetate (CMA) was tested in combination with hCG or the GnRH analogue deslorelin for its efficiency to induce ovulation in fourteen females without luteal activity and in three, regular cycling females. HCG (N = 12), injectable GnRH analogue (N = 8) and GnRH analogue implants (N = 15) were given to induce ovulation after CMA treatment. Treatment success was determined using both transrectal ultrasonography and progesterone metabolite EIA analysis. A preovulatory sized follicle (3.5 ± 0.1 cm) or a corpus luteum (5.1 ± 0.7) was present on the ovary one day after induction in 93.1% of the treatments. Despite this high rate of ovarian response, ovulation rate differed between the study groups. The ovulation rate for hCG, injectable GnRH analogue and GnRH analogue implants was 66.7%, 62.5% and 93.3%, respectively. Ovulation rate in cyclic females treated with GnRH implants was 100% (6/6) compared with 89% (8/9) in females without luteal activity receiving the same treatment. The length of the estrous cycle when induced with hCG was 4 wk (85.7%). The estrous cycle when induced with GnRH analogue was predominantly 10 wk long. Two females without luteal activity treated with GnRH became pregnant. In conclusion, CMA in combination with GnRH analogue implants was highly effective to induce ovulation in white rhinoceroses and thus can contribute to efforts aimed at increasing natural mating and reproductive rates in the captive white rhinoceros population.     

剪切波弹性成像对乳腺原位癌的诊断价值分析

目的:探讨剪切波弹性成像(SWE)对乳腺原位癌的诊断价值。方法:回顾性分析2015年8月-2017年8月于我院病理证实的26个乳腺原位癌病灶和45个乳腺良性病灶,术前均分别行常规超声检查和SWE检查。比较两组病灶的弹性模量值差异,两种检查方法诊断敏感度、特异度、准确度、阳性预测值、阴性预测值,并构建受试者操作特征(ROC)曲线,分析SWE对乳腺原位癌的诊断价值。结果:乳腺原位癌病灶的弹性模量最大值、平均值、最小值和与脂肪组织弹性比值分别为86.6±26.7 kpa、56.6±21.4kpa、31.3±15.7 kpa、6.7±1.8,均明显高于乳腺良性病灶(P0.05)。SWE诊断敏感度、特异度、准确度、阳性预测值、阴性预测值分别为92.31%、88.89%、90.14%、82.76%、95.23%,均显著高于常规超声成像(P0.05)。弹性模量最大值、平均值、最小值及与脂肪组织弹性比值评价乳腺原位癌的ROC曲线下面积分别为0.944、0.876、0.818、0.956。结论:乳腺原位癌病灶的弹性模量值高于良性病灶,SWE对早期发现乳腺原位癌具有重要价值。