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31.
Templeton AW; Johnson JA; Anderson WH; Cook LT; Dwyer SJ d; Preston DF; Lee KR; Rosenthal SJ; Batnitzky S; Levine E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use. 相似文献
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Eberl MM Sunga AY Farrell CD Mahoney MC 《The Journal of the American Board of Family Practice / American Board of Family Practice》2005,18(3):211-217
A family history of certain malignancies, especially breast, ovarian, colorectal, and prostate cancers, can place persons at increased risk of developing these cancers. By constructing a pedigree that includes 3 generations, family physicians can identify patients at increased risk because of family cancer history. Persons at increased cancer risk because of family history warrant a surveillance strategy for early detection. Genetic professionals represent an important resource in assessing genetic risk and possible testing. Persons identified as being at increased risk of various cancers based on their family history should understand the surveillance plan that is recommended and the importance of maintaining a healthy lifestyle and remaining up to date on other cancer screening tests. 相似文献
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BACKGROUND: Laboratory tests are widely used to screen children with planned surgery to detect unknown coagulation defects. This study investigates the predictive value of commonly used coagulation tests (thromboplastin time, partial thromboplastin time and thrombocyte count) compared with a standardized bleeding history. PATIENTS: In 702 patients 500 adenoidectomies and 500 tonsillectomies were done, results of laboratory evaluation and individual bleeding history were evaluated. RESULTS: 9.4 % of all laboratory tests showed abnormal results. 30.5 % of the children awaiting adenoidectomy had a suspicious bleeding history as had 22 % of patients undergoing tonsillectomy. In the clinical course of adenoidectomy no bleeding occurred. After tonsillectomy 15 children (3 %) showed moderate, 12 patients (2.4 %) severe postoperative bleeding. The positive predictive value of coagulation screening reached 6.8 % whereas history alone predicted 9.2 % of observed post tonsillectomy bleeding. CONCLUSIONS: The results of this study demonstrate the lacking effect of laboratory tests to predict postoperative bleeding complications. Taking a careful history of bleeding risks and testing only patients with suspicious history reduces the risk of bleeding more effective. Counseling about bleeding symptoms and postoperative survey of patients are additional measures which may protect the children. 相似文献
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Accumulation of a potent gammadelta T-cell stimulator after deletion of the lytB gene in Escherichia coli 下载免费PDF全文
Eberl M Altincicek B Kollas AK Sanderbrand S Bahr U Reichenberg A Beck E Foster D Wiesner J Hintz M Jomaa H 《Immunology》2002,106(2):200-211
Activation of human Vgamma9/Vdelta2 T cells by many pathogens depends on the presence of small phosphorylated non-peptide compounds derived from the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway of isoprenoid biosynthesis. We here demonstrate that in Escherichia coli mutants deficient in lytB, an essential gene of the MEP pathway, a potent Vgamma9/Vdelta2 T-cell activator accumulates by a factor of approximately 150 compared to wild-type E. coli. The compound responsible for the strong immunogenicity of this E. coli mutant was subsequently characterized and identified as a small pyrophosphorylated metabolite, with a molecular mass of 262 Da, derived from the MEP pathway. Stimulation of human peripheral blood mononuclear cells (PBMC) with extracts prepared from the lytB-deficient E. coli mutant led to upregulation of T-cell activation markers on the surface of Vgamma9/Vdelta2 T cells as well as proliferation and expansion of Vgamma9/Vdelta2 T cells. This response was dependent on costimulatory growth factors, such as interleukin (IL)-2, IL-15 and IL-21. Significant levels of interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) were secreted in the presence of IL-2 and IL-15, but not in the presence of IL-21, demonstrating that proliferating phosphoantigen-reactive Vgamma9/Vdelta2 T cells do not necessarily produce proinflammatory cytokines. 相似文献