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BACKGROUND: Cardiac magnetic resonance (MR) images are often reviewed by non-cardiologists who are not trained in the interpretation of regional left ventricular (LV) function. We hypothesized that the use of still-frame parametric MR images of wall motion could aid in the assessment of regional LV function. METHODS: Dynamic, electrocardiogram-gated, steady-state free precession (FIESTA) short-axis images were obtained in 6 to 10 slices in 18 consecutive patients. Each loop was used to automatically generate a still-frame image, in which each pixel is assigned a value equal to the amplitude of cyclic variation in local intensity, resulting in higher intensity in pixels that change between blood and tissue during the cardiac cycle. The dynamic images were reviewed by an expert cardiologist who provided gold standard grades for regional wall motion and by four radiologists. Then the radiologists reviewed and graded the same MR images in combination with parametric images. Grades assigned to each segment in the two sessions were compared with the gold standard. RESULTS: According to expert interpretation, 6 patients had normal wall motion, and 12 had wall motion abnormalities. Parametric images showed a bright band in the area spanned by endocardial motion, with reduced brightness and thickness in areas of hypokinesis. The agreement between the radiologists' grades and the gold standard significantly improved by adding parametric images (from 77% to 81%), which also resulted in reduced interobserver variability (from 52% to 33%). CONCLUSIONS: Still-frame parametric images aid in the assessment of regional wall motion by non-cardiologists who are required to interpret cardiac images.  相似文献   
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Purpose Studies on musculoskeletal manifestations (MSM) of childhood acute lymphoblastic leukemia (ALL) have yielded variable findings with regard to their clinical impact. We investigated the significance for differential diagnosis, treatment and outcome of musculoskeletal complaints as presenting symptoms of ALL, and their correlation with leukemia immunophenotypes, for which data is lacking. Methods Data on 783 children in the national study for childhood ALL between 1984 and 2003 were reviewed retrospectively. Statistical analysis examined possible relationships between MSM at the time of diagnosis and demographic and clinical data, biological features of leukemia (peripheral blood counts, immunophenotype and main cytogenetic aberration), response to initial prednisone treatment, and outcome. Results Of 765 children with data on orthopaedic complaints, 240 presented with MSM (31.4%). Among these children, B cell precursor (BCP) was much more common (209/576, 36.3%) than T cell ALL (25/176, 14.2%). Patients with MSM had lower white blood cell counts (WBC) (median of 9 vs. 20 × 109/L, P < 0.001) and percentage of blast cells in the peripheral blood at diagnosis compared to those without (median of 27 vs. 53%, P < 0.001). Hepatomegaly and splenomegaly were less common in MSM group (67 vs. 53% <3 cm, P < 0.001, and 63 vs. 50% <3 cm, P < 0.001, respectively). Poor response to initial treatment with prednisone was recorded in 7.1% of patients with MSM versus 11.5% of those without (P = 0.086). The analysis revealed no independent effect of MSM on event-free survival (EFS), after correcting for differences in EFS related to immunophenotype or initial WBC. Conclusions MSM occur mostly in children with BCP ALL who present with less involvement of extramedullary organs, low peripheral blood blasts and white blood cells counts. These findings highlight the importance of including ALL in the differential diagnosis of MSM even in the presence of an apparently normal peripheral blood count. Our study also suggests that MSM are caused by leukemic cells with enhanced biological propensity to remain relatively confined within the intramedullary bone-marrow space.  相似文献   
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Computed tomographic (CT) renal planimetry was used to study individual renal function in 32 adult patients with urologic disease. CT results were well-correlated to reference methods (r = 0.88, P < 0.001), which were radionuclide studies (N = 9) or separate creatinine clearance (N = 23). The difference between planimetric data and reference methods did not exceed 14% in any case and was less than 10% in 26 cases.  相似文献   
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This article is a review of the current commercial MR contrast media (gadolinium chelates) and of the products that are not yet on the market and are under trial in man (super-magnetic iron oxides, manganese compounds) or only in animals (ferric chelate, liposomes containing gadolinium compounds, gadolinium chelate/human serum albumin compounds, hepatic asialoglycoprotein receptors).  相似文献   
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A 61-yr-old man with Burkitt's lymphoma who presented with 6 months of diarrhea was found, at ileoscopy, to have inflammation of the mucosal narrow lumen, deep linear ulcerations, and a "cobblestone" appearance of the terminal ileum. Endoscopic biopsies were diagnostic of Burkitt's lymphoma, and no laparotomy was necessary. Presentation with diarrhea and the age of the patient were unusual, and the endoscopic features and diagnosis of the disease in the terminal ileum made by ileoscopy have not been previously reported.  相似文献   
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PROBLEM: To examine the relationship between the concentration of uterine fluid human decidua-associated protein (hDP) 200, identified as a monoclonal rheumatoid factor, and different phases of the menstrual cycle. METHODS: Sequential measurements of hDP 200 concentration in uterine fluid were performed in 11 normal ovulatory women, aged 22–36 years. The samples were collected in early proliferative phase, late proliferative phase, periovulatory period, early secretory phase, and late secretory phase. RESULTS: Consistent fluctuations of hDP 200 levels in uterine fluid were found throughout the menstrual cycle. High levels were found during early proliferative phase and periovulatory period related to significantly lower levels during late proliferative and early luteal phases. CONCLUSION: There is menstrual phase dependent variation in the uterine fluid levels of hDP 200.  相似文献   
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Shiga toxin (Stx)-producing Escherichia coli (STEC) is a major cause of sporadic cases of disease as well as serious outbreaks worldwide. The spectrum of illnesses includes mild nonbloody diarrhea, hemorrhagic colitis, and hemolytic-uremic syndrome. STEC produces one or more Stxs, which are subdivided into two major classes, Stx1 and Stx2. The ingestion of contaminated food or water, person-to-person spread, and contact with animals are the major transmission modes. The infective dose of STEC may be less than 100 organisms. Effective prevention of infection is dependent on rapid detection of the causative bacterial pathogen. In the present study, we examined 295 stool specimens for the presence of Stx-producing E. coli by three different methods: an Stx enzyme-linked immunosorbent assay, a conventional PCR assay, and a LightCycler PCR (LC-PCR) assay protocol recently developed by our laboratory at the Institute of Medical Microbiology at Hannover Medical School. Our intent was to compare these three methods and to examine the utility of the STEC LC-PCR protocol in a clinical laboratory. The addition of a control DNA to each sample to clearly discriminate inhibited specimens from negative ones enhanced the accuracy of the LC-PCR protocol. From our results, it can be concluded that LC-PCR is a very useful tool for the rapid and safe detection of STEC in clinical samples.  相似文献   
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BackgroundSelf-management is critical to optimizing the health of individuals with a chronic condition or disability and is, therefore, a central concept in individual and family-centered healthcare delivery. The purpose of this review is to report the state of the science of self-management for individuals with spina bifida (SB) from a lifespan perspective.ObjectiveThis review will summarize the (a) development and use of self-management skills and behaviors across the life span, (b) factors related to self-management behaviors, (c) development of generic or condition-specific measures of self-management used with a spina bifida population, and (d) development and/or outcomes of interventions to improve self-management in SB.MethodsThe search strategy was limited to primary research articles published between 2003 and 2019 and followed PRISMA guidelines. The databases searched included: PubMed, CINAHL, PsycINFO, Web of Science, Cochrane, and Google Scholar. Studies that addressed self-management concepts in individuals throughout the life span and published in English were included.ResultsThe search yielded 108 citations and 56 articles met inclusion/exclusion criteria. A systematic narrative synthesis was reported. The level of evidence identified was primarily Level III articles of good quality. Multiple demographic, environmental, condition and process factors were related to self-management behaviors. SB self-management instruments and intervention development and testing studies were identified.ConclusionsThis review provides a synthesis of the state of the science of self-management including factors related to self-management behaviors, preliminary evidence of instruments for use in SB, factors important to consider in the development and testing of future interventions, and gaps in the literature.  相似文献   
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