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排序方式: 共有830条查询结果,搜索用时 15 毫秒
821.
The carpal boss: an overview of radiographic evaluation 总被引:3,自引:0,他引:3
The carpal boss, an unmovable bony protuberance, is located on the dorsum of the wrist at the base of the second and third metacarpals adjacent to the capitate and trapezoid bones. This bony prominence may represent degenerative osteophyte formation and/or the presence of an os styloideum, an accessory ossification center that occurs during embryonic development. When this condition is symptomatic, patients present with complaints of pain and limitation of motion of the affected hand. The symptoms of carpal boss may result from an overlying ganglion or bursitis, an exterior tendon slipping over this bony prominence, or from osteoarthritic changes at this site. Radiographically, the view that best profiles the separate os styloideum is a lateral view utilizing 30 degrees of supination and ulnar deviation of the wrist. Once a diagnosis has been made, treatment can range from the use of nonsteroidal antiinflammatory medication and limited use of the wrist to surgical excision of the anatomic abnormality. 相似文献
822.
PM LOUGHNAN PN McDOUGALL H BALVIN LW DOYLE AL SMITH 《Journal of paediatrics and child health》1996,32(3):268-269
Abstract: The clinical details are reported of two premature infants who developed late onset haemorrhagic disease after receiving their initial doses of vitamin K1 prophylaxis intravenously. Both reported infants had received two doses of intravenous vitamin K1 , 0.1 mg, in the 1st week of life, and a further oral dose, 1.0 mg, at 4 weeks. Bleeding due to vitamin K deficiency occurred on days 74 and 84, respectively. Vitamin K deficiency bleeding is rare in low birthweight infants, probably because it has been routine practice to give such infants intramuscular vitamin K1 . One of the reported infants had cytomegalovirus hepatitis, the other did not have liver disease. These findings could be explained if intramuscular vitamin K1 were to have a longer duration of effect than intravenous vitamin K1 . This may be because intramuscular vitamin K1 acts as a depot preparation. The findings suggest that intravenous vitamin K1 is less effective than intramuscular for long-term prophylaxis against late onset haemorrhagic disease. Intravenous vitamin K1 should not be used for long-term prophylaxis in the prevention of late onset haemorrhagic disease. 相似文献
823.
Computed tomographic (CT) scans and magnetic resonance (MR) images in 103 patients with either a deep-lobe parotid tumor extending into the parapharyngeal space, a minor salivary gland tumor, a neuroma, or a paraganglioma were reviewed. The parotid or extraparotid nature of these masses was established by identifying a fat plane between the mass and the parotid gland. This was more reliably accomplished with MR imaging than with CT. Although dynamic CT allowed identification of the glomus tumors, MR imaging also permitted diagnosis of these lesions. The inherent CT and MR imaging characteristics of most of the neuromas and minor salivary gland tumors were indistinguishable. However, the neuromas tended to displace the internal carotid artery anteriorly, whereas the salivary lesions displaced this vessel posteriorly. This artery was better identified on MR images than on CT scans. Thus, these lesions, which are the four most common primary parapharyngeal space tumors, can be distinguished on MR images by evaluating not only their inherent signal characteristics but also the surrounding fat planes and any displacement of the internal carotid artery. 相似文献
824.
Fabry disease is a genetic disorder caused by the deficiency of α-galactosidase A, resulting in the lysosomal accumulation of glycosphingolipids. Fabry disease may result in cardiac, cerebral and renal complications. Cardiac abnormalities in patients with Fabry disease were first described in the 1960s. In the 1990s a form of Fabry disease confined to the heart was reported; however, this variant is extremely rare and a more appropriate concept is of cardiac predominance of the disease in some patients. Up to 60% of males with classic Fabry disease have cardiac abnormalities, including left ventricular hypertrophy, valvular dysfunction and conduction abnormalities. Recent data suggest that left ventricular mass and systolic function in patients with Fabry disease improve after 12 months of enzyme replacement therapy (ERT); however, many of the patients studied are relatively young and have mild cardiac abnormalities, suggesting that more research into the efficacy of ERT in older patients is necessary.
Conclusion: Cardiac manifestations are common in patients with Fabry disease and are not confined to a 'cardiac variant' of the disease. 相似文献
Conclusion: Cardiac manifestations are common in patients with Fabry disease and are not confined to a 'cardiac variant' of the disease. 相似文献
825.
Schumaclaer HC Meyers PM Higashida RT Derdeyn CP Lavine SD Nesbit GM Sacks D Rasmussen P Wechsler LR 曹亦斌 《中国脑血管病杂志》2010,7(1):49-55
背景和目的颅内动脉粥样硬化可造成众多患者发生缺血性卒中。过去10年间血管内治疗技术已经取得突破性进展,能够开展颅内动脉粥样硬化性狭窄的血管内治疗。采用血管成形术和支架辅助阻管成形术治疗颅内动脉粥样硬化性狭窄的患者例数不断增加。但是鉴于目前血管成形术和支架辅助血管成形术治疗狭窄性和闭塞性颅内动脉粥样硬化仍缺乏普遍认可的临床和放射学评估以及皿管内治疗技术及预后的规范,此文就是提供该方面报告标准、术语和书面定义的共识性建议。报告摘要报告标准是在技术评价委员会、神经介入外科学会、介入放射学会、美国神经外科医师协会和神经外科医师代表大会的脑血管外科分会、美国神经科学会的卒中和介入神经病学分会的联合写作组共同起草完成。对1997年1月-2007年12月间,美国国立图书馆医学文献数据库(PubMed)进行计算机检索,旨在确定已发表的狭窄性颅内动脉粥样硬化的神经介入治疗中,能用作质量评价基准的资料。我们尽可能地确定影响神经介入治疗成功及并发症可能性的危险调节变量。对狭窄性和闭塞性颅内动脉粥样硬化进行麻管内治疗的临床试验设计中,不同临床和技术问题可能影响血管内治疗的疗效,此文章为这些问题提供相关的理论基础。该指南中包括对血管内治疗试验报告标准的建议。虽然制定规范和标准主要是出于研究用途,但是这也将有助于临床实践,还适用于所有相关的出版物。结论总之,报告标准提出的建议将有助于构建有效的研究数据库,同时促进产生科学可靠的研究结果,使相似研究之间或内部能够进行可靠的比较。存某些情况下,为报告和出版的一致性,本文中的定义可能是写作组专家的共识性建议。这些建议将促使不同研究组的结果具有直接可比性。 相似文献
826.
Real-time sonography in suspected acute cholecystitis. Prospective evaluation of primary and secondary signs 总被引:1,自引:0,他引:1
Ralls PW; Colletti PM; Lapin SA; Chandrasoma P; Boswell WD Jr; Ngo C; Radin DR; Halls JM 《Radiology》1985,155(3):767-771
Sonographic findings in 497 patients with suspected acute cholecystitis were analyzed prospectively. Combined use of primary and secondary sonographic signs led to excellent positive and negative predictive values. Positive predictive values for stones combined with either a positive sonographic Murphy sign (92.2%) or with gallbladder wall thickening (95.2%) were excellent for acute cholecystitis. Positive predictive value of these signs for patients requiring cholecystectomy was even higher (99.0%). Negative predictive values for combined use of primary and secondary signs to exclude acute cholecystitis were also excellent (95.0% for no stones and negative sonographic Murphy sign). Real-time sonography alone, using both primary and secondary signs, can be definitive in nearly 80% of patients with suspected acute cholecystitis. These patients require no further imaging evaluation. Sonography should be the screening test of choice in acute cholecystitis because it is cost effective, prospectively highly accurate, quick, and better at characterizing and detecting other abdominal lesions than cholescintigraphy. A proposed algorithm is described. 相似文献
827.
Ralls PW; Henley DS; Colletti PM; Benson R; Raval JK; Radin DR; Boswell WD Jr; Halls JM 《Radiology》1987,165(3):801-804
Hepatic magnetic resonance (MR) imaging was performed in 12 patients with 13 amebic liver abscesses. While no specific image or intensity pattern was noted, most lesions were round or oval with smooth, well-defined margins; had decreased signal intensity compared with that of liver parenchyma on T1-weighted images and increased signal intensity on T2-weighted images; and had prominent, often multiple rims of variable signal intensity. Signal homogeneity within the abscess was present more often on T1- than on T2-weighted images. Diaphragmatic disruption was seen in two cases on coronal MR images. An amebic empyema was differentiable from sympathetic pleural effusions by its hyperintensity on both T1- and T2-weighted images. In patients who also underwent computed tomography (CT) or ultrasonography (US), no lesion was missed with any modality, and except for shape, no consistent features were found among images obtained with the different modalities. The data suggest that CT, US, and MR imaging are comparably effective in the detection of amebic abscess. 相似文献
828.
829.
K Jones M Edelbroek M Horowitz W M Sun J Dent J Roelofs T Muecke L Akkermans 《Gut》1995,37(5):643-648
Recent studies suggest that scintigraphy can be used to evaluate non-invasively antral motility in humans, although scintigraphic techniques have not yet been compared with more conventional measurements of intraluminal pressures by manometry. Simultaneous scintigraphic and manometric measurements of antral motility were performed in nine healthy volunteers. After intubation with a sleeve/sidehole catheter which incorporated five pressure sideholes located at 1.5 cm intervals spanning the antrum, each subject ingested 100 g minced beef labelled with 100 MBq 99mTc-chicken liver and 150 ml water. Between 40-43, 60-63, 80-83, and 100-103 minutes after meal ingestion, radioisotopic data were acquired in two second frames. Time-activity curves showing antral 'contractions' resulting from wall motion were derived by drawing small regions of interest over the antrum to coincide with the position of the antral manometric sideholes. Scintigraphic contraction rates approximated 3/minute, whereas antral pressure waves that occluded the lumen were less frequent (p < 0.01 for all), particularly in the proximal antrum. The amplitude of wall motion, evaluated scintigraphically, and the amplitude of pressure waves were both inversely related to the distance from the pylorus (r > -0.32, p < 0.05) and antral volume r > -0.29 (p < 0.05). There were significant relationships between the amplitude of contractions assessed scintigraphically and the number of lumen-occlusive antral pressure waves in the distal antrum (r -0.48, p < 0.05) but not in the more proximal antral regions. It is concluded that scintigraphy can detect antral wall motion with greater sensitivity than manometry, particularly in the proximal antrum. As manometry gives information on the amplitude as well as the temporal and spatial organisation of those contractions which result in lumen occlusion, the combination of scintigraphic and manometric techniques in the evaluation of antral motility shows considerable promise. 相似文献
830.