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1.
Digital radiography is an appropriate method for both bedside and in-department chest radiographs. Its major advantage in bedside chest radiography is its control of the displayed optical density of these radiographs. With dynamic range control processing, it improves the visibility of tubes and lines superimposed on the mediastinal tissues. When used for in-department chest radiography, it may offer slight advantages in the evaluation of disease in the mediastinum, but in general is equivalent to film-screen chest radiography. The main reasons for using digital chest radiography for in-department chest radiographs relate mainly to its use as a data entry point method of projection radiography for high-quality teleradiology or for its use in a picture archiving and communication system. Apart from these advantages, there is no reason to change from conventional to digital chest radiographs. Digital radiographs are, with certain systems, printed at smaller than life size. Because of this, there is a necessary period of learning as radiologists adjust to the new image size. The most important change in radiologists' work pattern appears to be the need to sit closer to the film. Findings of disease are smaller, but, with experience, just as easy to see. 相似文献
2.
Image processing is a critical part of obtaining high-quality digital radiographs. Fortunately, the user of these systems does not need to understand image processing in detail, because the manufacturers provide good starting values. Because radiologists may have different preferences in image appearance, it is helpful to know that many aspects of image appearance can be changed by image processing, and a new preferred setting can be loaded into the computer and saved so that it can become the new standard processing method.Image processing allows one to change the overall optical density of an image and to change its contrast. Spatial frequency processing allows an image to be sharpened, improving its appearance. It also allows noise to be blurred so that it is less visible. Care is necessary to avoid the introduction of artifacts or the hiding of mediastinal tubes. 相似文献
3.
4.
Matthew Freedman MD Dot Steller Hamid Jafroudi Seong Ki Mun 《Journal of digital imaging》1995,8(2):67-74
Quality control (QC) of storage phosphor devices is important in assuring that the image information entered into an Image management and communication (IMAC) system is sufficient for diagnosis. QC of storage phosphor digital radiography systems is complex because of the self-corrective nature of the image-processing software used in these machines. Currently, one must produce hard copy to perform adequate QC. Inspection of images with reject analysis and inspection of cassettes and imaging plates has helped us in our QC program. For those QC tests using control limits, the appropriate settings for these limits are unknown. Starting approximations are given. Recommended tests are described. 相似文献
5.
Rat strain differences in the early stage of porcine-serum-induced hepatic fibrosis. 总被引:1,自引:0,他引:1
Yasuko Baba Koji Uetsuka Hiroyuki Nakayama Kunio Dot 《Experimental and toxicologic pathology》2004,55(5):325-330
Rat strain differences in the early development of porcine serum (PS)-induced hepatic fibrosis were histologically and immunohistochemically examined using Brown Norway (BN), Sprague Dawley (SD) and Wistar rats. They were injected i.p. with 0.5 ml sterile PS twice a week for 4 and 8 weeks. In addition, rats treated with physiological saline in the same way served as controls. At 4 weeks, hepatic fibrosis accompanying fibrous septa mainly composed of type III collagens developed in BN and SD rats but not in Wistar rats. In addition, the numbers of eosinophils, CD3-positive cells and ED-1-positive cells significantly increased in BN and SD rats, that of CD45RA-positive cells in BN rats, and that of alpha-smooth muscle actin (SMA)-positive cells in SD rats, respectively. Such differences in the number of inflammatory cells may be related with the absence of hepatic fibrosis in Wistar rats at 4 weeks. At 8 weeks, hepatic fibrosis with formation of many small-sized pseudolobules was observed in all strains at almost similar degree, and the numbers of infiltrating cells increased in all strains of rats with some exception. In addition, the main location of inflammatory cells was different, suggesting a different role of each inflammatory cell in the process of hepatic fibrosis. 相似文献
6.
Goncalves Fernanda A. de Jesus Jessica Santos Cordeiro Lilian Piraciaba Maria Clara T. de Araujo Luiza K. R. P. Steller Wagner Martins Carolina Dalboni Maria Aparecida Pereira Benedito J. Silva Bruno C. Moysés Rosa Maria A. Abensur Hugo Elias Rosilene M. 《International urology and nephrology》2020,52(2):393-398
International Urology and Nephrology - Hypokalemia is a well-described electrolyte disturbance in patients on peritoneal dialysis (PD). Hyperkalemia, however, is still overlooked, although it also... 相似文献
7.
Korobelnik Jean-François Daien Vincent Faure Céline Tadayoni Ramin Giocanti-Auregan Audrey Dot Corinne Kodjikian Laurent Massin Pascale 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(3):521-528
Graefe's Archive for Clinical and Experimental Ophthalmology - To report the effectiveness of intravitreal aflibercept (IVT-AFL) treatment for diabetic macular edema (DME) in French clinical... 相似文献
8.
K. M. Govaert C. S. van Kessel E. J. A. Steller B. L. Emmink I. Q. Molenaar O. Kranenburg R. van Hillegersberg I. H. M. Borel Rinkes 《Journal of gastrointestinal surgery》2014,18(5):952-960
Aim
To assess the impact of first recurrence location on survival following surgery of colorectal liver metastases.Methods
A total of 265 consecutive patients with colorectal liver metastases undergoing liver surgery (2000–2011) were categorized according to first site of tumor recurrence. Time to recurrence (TTR) and overall survival (OS) were determined. Uni- and multivariate analysis were performed to identify factors associated with TTR and OS.Results
Median TTR was 1.16 years following liver resection, and 0.56 years following radiofrequency ablation (RFA). Intrahepatic recurrence following liver resection resulted in a significantly shorter median TTR compared to extrahepatic recurrence. Intrapulmonary recurrence was associated with superior survival compared to other recurrence locations. Such patterns were not observed in the RFA-treated group. Multivariate analysis identified the type of surgical treatment and extra-hepatic first-site recurrence (other than lung) as independent predictors for OS. Pre-operative chemotherapy and simultaneous intrahepatic and extrahepatic recurrence were independent predictors for both TTR and OS.Conclusions
Patients with intrahepatic recurrence following liver resection have a significantly shorter TTR and OS when compared to patients developing extrahepatic recurrence. Pulmonary recurrence following resection is associated with longer survival. Simultaneous intra- and extrahepatic recurrence is an independent prognostic factor for TTR and OS. 相似文献9.
Ewout S. Veltman Michel P.J. van den Bekerom Job N. Doornberg Diederik O. Verbeek Stefan Rammelt Ernst Ph. Steller Tim Schepers 《Injury》2014
This study determined inter- and intra-observer reliability for measurement of the angles of Böhler and Gissane, for the decision between surgical or conservative management and for the three mostly used classification systems for calcaneal fractures with the use of 2D-CT imaging versus 2D- and 3D-CT imaging. 相似文献
10.
Digital radiography (DR) is replacing screen-film (SF) radiography for musculoskeletal examinations in our institution. After an iterative process of image quality improvement, our DR images are now preferred to SF images, and we have detailed our current optimized settings for the Fuji 9000 (Fuji Medical Systems, Tokyo, Japan). DR offers the advantages of improved contrast resolution, adjustable image contrast, the ability to reprocess the image, and the ease of transferring the image to an image management and communication system (IMAC). 相似文献