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91.
The poor prognosis of patients with trisomy 13 has long been accepted and has been ascribed to brain and heart malformations. It has been suggested, however, that the long term survival is better than was previously thought and that cardiac surgery may be justified. This population based study reviews the incidence, antenatal diagnosis, spectrum of survival from congenital heart disease, and mode of death for patients with trisomy 13 in the Northern Health Region from 1985 to 1992. There was an observed prevalence at birth of 0.049/1000 live births and an expected prevalence, allowing for antenatal diagnosis, of 0.077. None of the cardiac lesions found would cause early death. The median survival in this series was four days; the longest survival was 3.5 months. The principal mode of death was apnoea in 14 of 16 children, irrespective of the presence of a cranial abnormality. In the light of these findings, cardiac surgery cannot be justified in patients with trisomy 13. 相似文献
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多肽研究XX:丙型肝炎病毒(HCV)合成多肽的抗原性及线性抗体谱 总被引:1,自引:0,他引:1
依据蛋白质的亲水性、可亲性、柔韧性、抗原性、电荷分布及HPLC滞留系数等六种性质,使用“Goldkey”软件系统给出了HCV-BK各蛋白抗原决定簇预测曲线,共设计、合成15个多肽片段:P1(475~495),P3(449~468),P4(658~663),P5(645~663),P6(484~489),P7(475~489),P15(655~662),P16(230~237),P17(225~237),P18(1220~1240),P19(1694~1735),P24(1230~1240),P25(1482~1493),P26(384~389)和P27(2355~2389)。发现NS1区%和NS4区P19有很强的抗原性。用其检测PT-HC,阳性率分别为60%和63%。 相似文献
95.
The reliability of proton spectroscopic imaging in evaluating fatty infiltration of the liver was investigated in 35 subjects (12 healthy volunteers and 23 patients with fatty livers). With this modified spin-echo technique, fatty liver could be separated from normal liver both visually and quantitatively. On the opposed image, normal liver had an intermediate signal intensity, greater than that of muscle, whereas fatty liver had a lower signal intensity, equal to or less than that of muscle. In normal livers, the lipid signal fraction was less than 10%, while in fatty livers it was greater than 10% and usually exceeded 20%. With this technique, nonuniform fatty infiltration of the liver can be differentiated from hepatic metastases, and the technique may prove useful in the differentiation of some hepatic disorders. 相似文献
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Direct demonstration of transsynaptic degeneration in the human visual system: a comparison of retrograde and anterograde changes 总被引:1,自引:0,他引:1 下载免费PDF全文
RM Beatty AA Sadun LEH Smith JP Vonsattel EP Richardson Jr 《Journal of neurology, neurosurgery, and psychiatry》1982,45(2):143-146
Transneuronal degeneration of retinal ganglion cells was directly demonstrated in a patient who had unilateral removal of the striate cortex forty years prior to necropsy. For comparison, another case is presented showing anterograde transneuronal atrophy forty years after enucleation of one eye. 相似文献
98.
A new technique is described for reversing the direction of the catheter tip during translumbar aortography, without the need for partial withdrawal of the catheter from the aortic lumen. The method ensures optimal delivery of contrast medium at the desired level, while avoiding the risk of retroperitoneal bleeding or dislodgement during catheter manipulation. 相似文献
99.
Five patients with optic neuropathy, four vascular and one demyelinating, are described who each complained of an unusual symptom. Bright flashes of light (phosphenes) occurred in the affected eyes and were evoked by sudden unexpected sounds. Movement of the eye alone did not reproduce the symptom. In all patients the phenomenon was sufficiently prominent to interfere with sleep and was the main complaint of one patient. An anticonvulsant (phenytoin) greatly reduced the frequency and intensity of the phosphene in one patient. 相似文献
100.
Differential CT diagnosis of extruded nucleus pulposus 总被引:1,自引:0,他引:1