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991.
Multiple peripheral pulmonary artery stenoses were detected in three patients with congenital generalised lipodystrophy. This association, which has not been described before, may be clinically important in patients with lipodystrophy who present with impaired exercise tolerance or heart murmurs. 相似文献
992.
NG Anderson JL Fenwick JE Wells 《Journal of Medical Imaging and Radiation Oncology》2006,50(2):127-131
Our aim was to determine the degree of bias in CT scanogram measurements. We obtained standard lateral and anteroposterior (AP) pelvimetry scanograms of a phantom pelvis after placing ball bearings or aluminium rods to mark bony landmarks. Computed tomography pelvimetry was carried out at the manufacturer‐recommended table height on two commercial CT scanners and at 10‐mm increments up to 50 mm above and below this height. The AP inlet, AP outlet, interspinous distance and transverse diameters were each measured three times for each scanogram. The true measurements were obtained directly from the disassembled phantom. Bias was defined as the difference between the CT measurement and the true measurement. Observer error was negligible. The transverse diameter was overestimated at high table positions and underestimated at low table positions on both scanners (+6 to ?10 mm). After correcting for geometric distortion, up to 6 mm bias was still present. The point at which no bias occurred was different for each scanner and did not correspond to the manufacturers’ recommended table height. The outlet was overestimated on both scanners by up to 5 mm. The true inlet measurement was overestimated by 1.2 mm. The interspinous distance was minimally underestimated on both scanners. The measurements on CT scanogram were underestimated or overestimated in an inconsistent and unpredictable fashion, varying from one type of measurement to another and from CT scanner to CT scanner. This has implications for the accuracy and clinical utility of measurements obtained from a CT scanogram. 相似文献
993.
994.
J L Gerberding 《Journal of thoracic imaging》1991,6(4):12-15
Health care workers may be occupationally exposed to human immunodeficiency virus (HIV). The risk of infection is highest with accidental needlestick and similar percutaneous exposures. Emphasis should be placed on avoiding this type of accident. Strategies to prevent accidents and to manage exposures once they have occurred should be developed in each work environment. It is to be hoped that a combination of better infection control, safer devices and technologies, and postexposure prophylaxis with zidovudine (AZT) or other chemotherapeutic agents will help prevent infection in health care providers caring for HIV-infected patients. 相似文献
995.
Transient osteoporosis of the hip: MR imaging 总被引:12,自引:0,他引:12
Three patients with transient osteoporosis of the hip underwent magnetic resonance (MR) imaging. MR images showed decreased signal intensity of bone marrow in the femur on T1-weighted images and increased signal intensity relative to the intensity of normal bone marrow on T2-weighted images. Joint effusions were seen on MR images of all patients on T2-weighted images. The findings on MR images concurred with histologic findings, such as increased bone turnover and mild inflammatory reaction, in one patient. The clinical symptoms and abnormalities on MR images regressed completely within 6-10 months. Familiarity with the distinct features of transient osteoporosis on MR images may be important in the differential diagnosis of adults with hip pain. 相似文献
996.
Wang Y; Best DE; Hoffman JG; Horii SC; Lehr JL; Lodwick GS; Morse RR; Murphy LL; Nelson OL; Perry J 《Radiology》1988,166(2):529-532
The purposes, implications, and history of development of the American College of Radiology-National Electrical Manufacturers Association (ACR-NEMA) Digital Imaging and Communication Standard and its contents are briefly described, and the minimum requirements of the ACR-NEMA Digital Imaging and Communication Standard are described with a concise introduction of each layer. The usefulness, validity, current status, and future development of the standard are also discussed. 相似文献
997.
目的 :研究月桂氮艹卓 酮及电穿孔技术对萘普生经皮渗透的影响。方法 :应用双室扩散池方法研究促渗剂月桂氮艹卓 酮及电穿孔技术对萘普生在离体大鼠腹部皮肤经皮渗透的影响。结果 :电穿孔 (指数衰减型脉冲 ,脉冲幅度为 380V ,电容器电容为2 2 μF ,脉冲率为 4pulses·min 1,脉冲宽度τ≈ 5 .5ms ,脉冲数 10 0个 )、月桂氮 艹卓 酮预处理皮肤或两者合用均可显著促进萘普生的渗透速率和累积渗透量。两者合用的渗透速率与电穿孔或月桂氮 艹卓 酮预处理的渗透速率无显著差异。结论 :月桂氮 艹卓 酮预处理及电穿孔技术均能明显促进萘普生的经皮渗透 ,两者合用并无协同作用 相似文献
998.
Meningeal carcinomatosis in the VX2 rabbit tumor model: detection with Gd-DTPA-enhanced MR imaging 总被引:4,自引:0,他引:4
Meningeal carcinomatosis developed in 14 of 14 New Zealand White rabbits after infusion of a VX2 tumor cell suspension into the cisterna magna. All died or were killed 7-15 days after inoculation. Within days of the tumor infusion, magnetic resonance (MR) imaging with gadolinium-diethylenetriaminepentaacetic acid (DTPA) at 0.5 or 1.5 T demonstrated enhancement of the cerebrospinal fluid (CSF) secondary to disruption of the blood-CSF barrier by plaquelike lesions along the meninges. Eventually, meningeal enhancement was observed along the base of the brain and cervical spine. Quantitative assessment of the contrast enhancement on T1-weighted images revealed an increase in mean signal intensity of 213% +/- 130%. Contrast enhancement was not observed in four control animals who received an infusion of cell culture medium. These results demonstrate in an animal model that contrast material-enhanced MR imaging can be used to detect meningeal carcinomatosis by revealing breakdown of the blood-CSF barrier. 相似文献
999.
Screening blood donors for gastrointestinal illness: a strategy to eliminate carriers of Yersinia enterocolitica 总被引:3,自引:0,他引:3
BJ Grossman ; P Kollins ; PM Lau ; JL Perreten ; RJ Bowman ; S Malcolm ; WM Palko 《Transfusion》1991,31(6):500-501
Recent reports of fatal transfusion-associated Yersinia enterocolitica sepsis prompted a study of the feasibility of adding a question to the routine donor health history as a method of reducing this risk. In three American Red Cross blood centers, 11,323 donors were asked one of two questions about gastrointestinal symptoms during their health history screenings. Affirmative responses were obtained from 0.6 or 4.0 percent of the donors, depending on how the question was asked. In one center, more than 6 percent of donors gave affirmative answers. The efficacy of asking a relatively simple question about gastrointestinal symptoms as a way of preventing Y. enterocolitica should be evaluated further, because relatively large numbers of donors may respond affirmatively. Other methods of reducing the risk of transfusion-associated Y. enterocolitica infection should be pursued. 相似文献
1000.