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71.
Ultrasound-guided in utero injections into the brain of murine embryos has been shown to facilitate gene delivery. We investigated whether these methods would allow gene transfer into ocular structures. Gene transfer using retroviral vectors or electroporation was found to be quite effective. We determined the window of time, as well as compared several strains of mice, that yield a high degree of survival and successful gene transfer. Several retroviral constructs were tested for expression and coexpresssion of two genes in retinal cell types. In addition, a retroviral vector was engineered to give cone photoreceptor-enriched expression, and a retroviral vector was demonstrated to provide RNAi-mediated loss-of-function. These methods enable access to early ocular structures and provide a more rapid method of assessment of gene and promoter function than possible using genetically engineered mice. 相似文献
72.
Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease. 相似文献
73.
Robin M. Winter Martin D'A. Crawfurd Hylton B. Meire Nan Mitchell 《Clinical genetics》1980,18(6):462-474
Cranial sclerosis with osteopathia striata was diagnosed in four members of a family in three generations. The expression of the gene varied from mild cranial enlargement to cranial abnormality associated with severe Pierre-Robin triad. The disorder was diagnosed prenatally in the most severely affected member of the family from the finding of an increased biparietal diameter of the fetal head on ultrasound examination. 相似文献
74.
Improvement in Doppler ultrasound human foetal heart rate records by signal correlation 总被引:1,自引:0,他引:1
D. L. Tuck 《Medical & biological engineering & computing》1982,20(3):357-360
An improved method for the determination of foetal heart rate from Doppler ultrasound signals is described and evaluated.
It determines the most probable pulse interval from the recurrence times of multiple echoes generated by each cardiac pulse.
The method, when optimised, is shown to offer an improvement over current systems, especially in reduced signal loss. 相似文献
75.
The objectives were (1) to determine the effect of the erythrocyte aggregation level (wide range of aggregation) and shear rate (which also affects aggregation) on the ultrasound backscattered power, and (2) to evaluate the reproducibility of the ultrasound method. Experiments were performed under steady flow (100–1250 ml/min) in a 12.7 mm diameter vertical tube. Doppler ultrasound at 10 MHz was used to measure simultaneously the velocity and the backscattered power across the tube. For each radial position, the shear rate was computed from the derivative of the velocity profile. The backscattered power decayed exponentially as a function of the shear rate, and for a given shear rate, the power increased monotonically with the level of aggregation measured by laser reflectometry. Using blood samples simulating hypo-, normal, and hyperaggregating erythrocytes, the power of the ultrasound signal varied respectively by –7.8, –13.2, and –16.1 dB as a function of the shear rate (from 0.4 to 50 s–1). The reproducibility of the backscattered power was 5.5 dB, which is less than the variations observed as a function of the shear rate. In conclusion, ultrasound backscattering is sensitive to the level of erythrocyte aggregation. At a first glance, ultrasound seems less accurate when compared to laser reflectometry but it is suggested that this is because ultrasound backscattering may be sensitive to structural aggregate changes that are not detected by the laser method. © 2000 Biomedical Engineering Society.
PAC00: 8718-h, 8719Tt, 8750Kk 相似文献
76.
Bovicelli L Ghi T Pilu G Farina A Savelli L Simonazzi G Calzolari E Ferlini A Santini D Valeri B 《Human reproduction (Oxford, England)》2004,19(5):1231-1234
A complete mole coexisting with dichorionic twins was diagnosed by the combined use of sonography and chorionic villus sampling at 10 weeks gestation. The pregnancy resulted in the death of one fetus at 31 weeks from presumed feto-maternal haemorrhage, while the other fetus survived in good condition. A summary of the available literature, combined with this report, reveals a total of seven pregnancies with twins and a coexistent complete mole. Only two out of 14 fetuses survived. Maternal complications included one case of pre-eclampsia and one persistent trophoblastic tumour. Accurate diagnosis of complete mole is possible by genetic analysis of chorionic villi obtained with standard transabdominal sampling. Twins with a coexistent complete mole will usually undergo miscarriage. However, fetal survival is possible and the maternal risks seem limited. A concomitance between gestational trophoblastic disease and the occurrence of feto-maternal haemorrhage is observed. 相似文献
77.
目的:探讨经阴道彩色多普勒超声对子宫腺肌瘤的诊断价值。方法:选取许昌中医院2020年1月至2022年1月期间收治的80例子宫腺肌瘤患者为研究对象,对上述患者实施经阴道彩色多普勒超声诊断,获得对应的诊断结果,随后将该结果和术后病理分析结果进行比较,最终得出诊断效果。结果:本研究80例子宫腺肌瘤患者中,经阴道彩色多普勒超声检出75例,漏诊或误诊5例,诊断准确率为93.75%;经阴道彩色多普勒检查诊断为子宫腺肌瘤的75例患者中,按照发病部位划分,有10例(13.33%)子宫腺肌瘤出现在子宫前壁区域,65例(86.67%)出现在子宫后壁部位;按照病情特点划分,有63例(84.00%)为单发子宫腺肌瘤,12例(16.00%)为子宫腺肌瘤合并子宫肌瘤。此外,75例患者中有3例患者并发卵巢内膜异位症。75例患者的子宫动脉血流阻力指数为0.75±0.05、搏动指数为1.37±0.04、舒张期峰值速度为(5.83±0.14)cm·s-1、收缩期峰值速度为(71.74±0.25)cm·s-1。结论:经阴道彩色多普勒超声可通过超声特征、血流分布、多普勒频谱特点,准... 相似文献
78.
目的探讨复发性剖宫产瘢痕部位妊娠(RCSP)发生的相关因素及处理。方法选取2015年1月至2021年1月于川北医学院附属医院妇产科确诊的463例CSP并行聚焦超声消融(FUAS)或子宫动脉介入栓塞(UAE)联合宫腔镜手术治疗患者,随访其再妊娠情况,失访72例,成功随访391例,117例再次妊娠,24例为RCSP。回顾性分析RCSP患者的临床资料和处理方式。结果391例CSP患者,122例行FUAS联合宫腔镜手术,34例再次妊娠,5.9%(2/34)为RCSP;269例行UAE联合宫腔镜手术,83例再次妊娠,26.5%(22/83)为RCSP。UAE组RCSP发生率高于FUAS组,差异有统计学意义(P<0.05)。24例RCSP患者,22例行FUAS联合宫腔镜手术,2例行UAE联合宫腔镜手术,均一次性治疗成功。RCSP患者中,79.2%(19/24)剖宫产≥2次,87.5%(21/24)人工流产≥2次,70.8%(17/24)子宫下段瘢痕厚度≤3 mm。结论既往多次剖宫产史、多次人工流产史、子宫下段瘢痕厚度偏薄及CSP初次治疗方式可能与CSP复发相关。FUAS联合宫腔镜手术是CSP及RSCP的适宜治疗方式。 相似文献
79.
目的 探讨二维超声对原发性肾病综合征预后的判断价值。方法 根据临床检查结果将 12 0例原发性肾病综合征患者分为 3组 ,并与二维超声检查结果进行相关性分析。结果 完全缓解组的肾脏超声检查结果与对照组比较无显著性差异 (P >0 .0 5 ) ,部分缓解组的肾脏超声检查结果与对照组比较有显著性差异 (P <0 .0 5 ) ,无效组的肾脏超声检查结果与对照组比较有非常显著性差异 (P <0 .0 1)。结论 二维超声检查原发性肾病综合征患者的肾脏无异常时预后良好 ,而肾脏缩小越明显 ,肾皮质回声越强 ,则预后越差。 相似文献
80.
介绍“超声信息管理系统”中的数据整合研究。医院数学化仪器和计算机信息系统的使用积累了大量的数据,本文针对“高血压进程与心脏形态变化的关系”这一主题,重组计算机内的积累病例数据,在建立数据仓库和实现数据挖掘方面做了一些尝试。 相似文献