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101.
A 14-month-old girl presented with a 4-d history of fever and generalized exanthema. Four characteristic symptoms of incomplete Kawasaki disease (KD) were present on admission (fever, rash, non-purulent conjunctival injection, oropharyngeal changes) and then followed by oedema of the hands and feet and mild plantar desquamation. The typical laboratory features of KD, such as elevated erythrocyte sedimentation rate, leukocytosis, thrombocytosis, and positive C-reactive protein were also seen. Ultrasound examination of the mediastinum revealed the presence of a lymph node, 30 mm in diameter, below the tracheal carina. Thoracic CT scan confirmed the mediastinal lymph node. The patient was treated with aspirin and intravenous γ -globulin. Ultrasound study of the mediastinum, which was carried out 6 weeks after hospital discharge, showed that the lymph node had disappeared. This case illustrates that lymph nodes other than cervical lymphadenopathy should be sought when the diagnosis of classical or atypical KD is suspected.  相似文献   
102.
We studied nine cases of retrobulbar neuritis with confirmed multiple sclerosis and six cases of optic atrophy from other causes. Pattern and focal electroretinograms (macular ERGs) were recorded with high (400 cd/m2) and low (40 cd/m2) intensity stimuli. Contrast sensitivity was also measured with a simple printed test.Luminance was not markedly important. High spatial frequency contrast sensitivity was significantly correlated with pattern ERG amplitude. Pattern and focal ERG amplitude ratio was usually reduced, but the effect was not correlated with contrast sensitivity or large enough to be useful clinically.In optic atrophy the pattern ERG (PERG) was clearly more severely reduced than the focal ERG (FERG). In retrobulbar neuritis both ERGs were equally and more severely reduced even though the visual losses were less. In unilateral cases the PERG increased then decreased after the initial attack, as previously described (Arden et al., 1982). The results suggest that retinal layers beyond the ganglion cells may be affected in retrobulbar neuritis, but proximally generated, pattern-specific ERG components are selectively lost in optic atrophy.  相似文献   
103.
论公费医疗大额死亡病例的资源消耗与医学目的   总被引:4,自引:2,他引:2  
从北京市公费医疗大额消耗的92例死亡病例的费用结构及住院城数的统计,提示由住院日地长,贵重卫生资源的盲目过量投入等而致。这与中国国情不符。因此,医学目的概念应更新,以及应如何正确对待死亡病例的医疗服务值得进行讨论。  相似文献   
104.
105.
牟鑫 《医疗设备信息》2003,18(11):34-35
近年来,超声定量检查技术在临床的应用为心血管疾病患者的心功能评估提供了量化的依据,本文介绍了超声诊断仪的使用部分最新定量检查技术。  相似文献   
106.
A tiered testing strategy has been developed to evaluate the potential for new ingredients, tobacco processes, and technological developments to alter the biological activity that results from burning tobacco. A series of studies was initially conducted with cigarettes containing 3% high fructose corn syrup (HFCS) as an alternate tobacco casing material to corn syrup/invert sugar, including determination of selected mainstream cigarette smoke (MS) constituent yields, Ames assay, sister chromatid exchange (SCE) assay in Chinese hamster ovary (CHO) cells, a 30-week dermal tumor-promotion evaluation of cigarette smoke condensate (CSC) in SENCAR mice, and a 13-week subchronic inhalation study of MS in Sprague-Dawley rats. A second series of studies was conducted with cigarettes containing 3%, 4% and 5% HFCS including MS chemistry, Ames assay, SCE assay in CHO cells, and a neutral red cytotoxicity assays. Collectively, mainstream smoke chemistry, genotoxicity, dermal tumor-promotion, and inhalation toxicity studies demonstrated no differences between cigarettes with 3% HFCS and cigarettes with 3% corn syrup/invert sugar. Also, mainstream smoke chemistry and genotoxicity of cigarettes with 4% and 5% HFCS were not different from cigarettes with 3% HFCS. In conclusion, the addition of up to 5% HFCS to cigarette does not alter the mainstream smoke chemistry or biological activity of mainstream smoke or mainstream smoke condensate as compared to cigarettes with 3% corn syrup/invert sugar with regard to the parameters investigated and presented.  相似文献   
107.
目的:探讨透明晶体超声乳化吸出并植入后房型折叠人工晶体矫正高度近视的安全性和有效性.方法:对32例(50眼)均采用表麻下经透明角膜切口行透明晶体超声乳化吸出并植入后房型折叠人工晶体.眼轴长平均29.64mm.比较手术前后最佳矫正视力(BCVA),散光度及角膜内皮计数,随访观察手术并发症情况.并对术前BCVA低于0.3的37只患眼应用扫描激光检眼镜(SLO)的微视力软件,检查微视力,评估术后潜在视力.周边视网膜格子样变性7只眼,均行氩激光周边变性区光凝.结果:术后随访平均24月.BCVA由术前0.20±0.19,术后提高到0.61±0.24,其中≥0.5的由术前4只眼(8%)增加到34只眼(68%)。手术前后平均散光度比较,经t检验无显著性差异(P>0.1).手术后无1例发生视网膜脱离,有5只眼发生后发障,均行YAG激光治疗.角膜内皮计数术后平均损失207个/mm2±96个/mm2.且SLO作为术后潜在视力预测手段拥有很高的准确度(94.6%).结论:透明晶体超声乳化摘除加后房型折叠人工晶体植入矫正高度近视是少数屈光矫正有效方法之一,可获得较好的术后BCVA.但是熟练掌握超声乳化手术操作及采取术前积极的预防性治疗是开展此项技术的根本和关键,且需进行长期的临床随访.  相似文献   
108.
One prerequisite for standard clinical use of intravascular ultrasound imaging is rapid evaluation of the data. The main quantities to be extracted from the data are the size and the shape of the lumen. Until now, no accurate, robust and reproducible method to obtain the lumen boundaries from intravascular ultrasound images has been described. In this study, 21 different (semi-)automated binary-segmentation methods for determining the lumen are compared with manual segmentation to find an alternative for the laborious and subjective procedure of manual editing. After a preprocessing step in which the catheter area is filled with lumen-like grey values, all approaches consist of two steps: (i) smoothing the images with different filtering methods and (ii) extracting the lumen by an object definition method. The combination of different filtering methods and object definition methods results in a total of 21 methods and 80 experiments. The results are compared with a reference image, obtained from manual editing, by use of four different quality parameters—two based on squared distances and two based on Mahalanobis distances. The evaluation has been carried out on 15 images, of which seven are obtained before balloon dilation and eight after balloon dilation. While for the post-dilation images no definite conclusions can be drawn, an automated contour model applied to images smoothed with a large kernel appears to be a good alternative to manual contouring. For pre-dilation images a fully automated active contour model, initialized by thresholding, preceded by filtering with a small-scale median filter is the best alternative for manual delineation. The results of this method are even better than manual segmentation, i.e. they are consistently closer to the reference image than the average distance of all individual manual segmentations.  相似文献   
109.
Two-step endoscopic resection of gastric leiomyomas   总被引:2,自引:0,他引:2  
Summary Our two-step technique for endoscopic treatment of gastric leiomyomas is illustrated. From January 1979 to June 1991, nine symptomatic patients with sessile leiomyomas of the stomach were treated at the Endoscopy Division of Istituto Nazionale Tumori, Milan.The diagnosis was achieved by means of endoscopic observation of the lesion and, when possible, by ultrasound endoscopy.This new technique consists of first removing superficial portion of the tumor by electrosurgical snare. Second, a cleavage plane is found within the proper muscle layer; the tumor is enucleated as much as possible by tightening the snare around it and creating a pseudo-stalk. No major complication occurred nor were any recurrences observed at 21.8 months in the 7/9 patients treated by endoscopy alone. Endoscopic therapy was performed on an outpatient basis and only large lesions required short hospitalization.  相似文献   
110.
Ultrasonic transmission imaging has already demonstrated potential for evaluating structures in the hand. In this study, a cadaver hand was imaged using a transmission scanner with improved imaging capability. The hand was then frozen and serially sectioned and comparisons were made between the sectional anatomy and the corresponding image. Bone (in silhouette), muscle, cartilage, and tendon were visualized with high resolution.  相似文献   
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