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排序方式: 共有1152条查询结果,搜索用时 15 毫秒
1.
《Diagnostic and interventional imaging》2020,101(6):335-345
This article was designed to provide a pediatric cardiac computed tomography angiography (CCTA) expert panel consensus based on opinions of experts of the Société Française d’Imagerie Cardiaque et Vasculaire diagnostique et interventionnelle (SFICV) and of the Filiale de Cardiologie Pédiatrique Congénitale (FCPC). This expert panel consensus includes recommendations for indications, patient preparation, CTA radiation dose reduction techniques, and post-processing techniques. The consensus was based on data from available literature (original papers, reviews and guidelines) and on opinions of a group of specialists with extensive experience in the use of CT imaging in congenital heart disease. In order to reach high potential and avoid pitfalls, CCTA in children with congenital heart disease requires training and experience. Moreover, pediatric cardiac CCTA protocols should be standardized to acquire optimal images in this population with the lowest radiation dose possible to prevent unnecessary radiation exposure. We also provided a suggested structured report and a list of acquisition protocols and technical parameters in relation to specific vendors. 相似文献
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Selecting an appropriate working correlation structure is pertinent to clustered data analysis using generalized estimating equations (GEE) because an inappropriate choice will lead to inefficient parameter estimation. We investigate the well‐known criterion of QIC for selecting a working correlation structure, and have found that performance of the QIC is deteriorated by a term that is theoretically independent of the correlation structures but has to be estimated with an error. This leads us to propose a correlation information criterion (CIC) that substantially improves the QIC performance. Extensive simulation studies indicate that the CIC has remarkable improvement in selecting the correct correlation structures. We also illustrate our findings using a data set from the Madras Longitudinal Schizophrenia Study. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
4.
Patterns of calcifications and cholangiographic findings in hepatobiliary tuberculosis 总被引:3,自引:0,他引:3
Dean D. T. Maglinte M.D. Sol Z. Alvarez Anastacio C. Ng Jose L. Lapeña 《Abdominal imaging》1988,13(1):331-335
The radiologic findings on conventional examinations (plain films and cholangiograms) in a large group of patients with proven hepatobiliary tuberculosis are reviewed. The plain film findings of large chalky and confluent hepatic calcifications or nodal-type calcifications along the course of the common bile duct are suggestive of hepatobiliary tuberculosis. Small, discrete, scattered calcifications may be mimicked by histoplasmosis but can be differentiated from hepatobiliary tuberculosis. Obstructing defects seen on cholangiography are indicative of tuberculosis when adjacent calcifications are present. The patterns of liver calcifications could provide a clue to the diagnosis of hepatobiliary tuberculosis and its differentiation from liver calcifications of various other etiologies. 相似文献
5.
OBJECTIVE: To examine the feasibility of using a behavioral coding system, the Five Minute Speech Sample (FMSS), to estimate the prevalence of relationship difficulties between parents and physicians in a pediatric asthma care setting. METHOD: The FMSS was administered to 20 parents of children with severe, chronic asthma and to the physicians they worked with during a brief day program admission. RESULTS: Rates of relationship difficulties between parents and physicians ranged from 15% to 40%, comparable to those previously identified in patient-therapist relationships in psychiatric populations. CONCLUSIONS: Although further information is needed about validity and reliability, the FMSS appears to provide clinically relevant information about the parent-physician relationship in the context of pediatric chronic illness. 相似文献
6.
Analysis of depressed cell-mediated immunity in asbestos workers 总被引:1,自引:0,他引:1
R D deShazo J Nordberg Y Baser B Bozelka H Weill J Salvaggio 《The Journal of allergy and clinical immunology》1983,71(4):418-424
To explore the mechanisms of asbestos-related perturbations of the immune system, we evaluated the in vitro cell-mediated immunity of five asymptomatic asbestos workers with hypergammaglobulinemia and decreased T-cell numbers. These results were compared with those in 10 matched controls. Analysis of T-lymphocyte populations revealed decreased absolute numbers of OKT4+ (helper/inducer) T cells in the peripheral blood and phytohemagglutinin (PHA)-stimulated mononuclear cell cultures of the workers. When chrysotile asbestos was added to PHA cultures, expansion of OKT4+ cell populations was disproportionately inhibited in workers' cultures. Furthermore, control proliferative responses to PHA became indistinguishable from initial worker responses. These effects were incompletely explained by the cytotoxic effects of asbestos on cultured lymphocytes. We conclude that both in vivo and in vitro exposure of mononuclear cell populations to asbestos may lead to a diminution of helper-inducer T-cell numbers. In asbestos-exposed individuals, this latter lymphocyte subpopulation appears to be especially sensitive to in vitro asbestos exposure. Although the clinical implications of these findings are unclear, we hypothesize that many of the immunologic abnormalities that occur in asbestos workers could be explained by direct asbestos effects on the OKT4+ immunoregulatory population. 相似文献
7.
《中华耳科学杂志(英文版)》2022,17(4):232-238
ObjectiveTo determine the circadian influence on sound sensitivity produced by temporal hearing deprivation in healthy normal human subjects.DesignParticipants underwent bilateral earplugging before completion of anthropometry, the author's developed questionnaire, the Hamilton Anxiety and Depression Inventory, pure tone audiometry (PTA), stapedial reflex thresholds (SRT), distortion products otoacoustic emissions input/output (DPOAE-I/O), and uncomfortable loudness levels (ULLs). Afterward, the participants were randomly divided into group A, starting at 8:00 a.m. and finishing at 8:00 p.m., and group B, starting at 4:00 p.m. and ending at 4:00 a.m. Serum cortisol levels and audiological test results were obtained at the beginning and end of the session and 24-h free urinary cortisol levels were measured.Study sampleThirty healthy volunteers.ResultsPTA was 2.68 and 3.33 dB HL in groups A and B, respectively, with no statistical difference between them. ULLs were significantly lower in group A compared to group B, with an average of 8.1 dB SPL in group A and 3.3 dB SPL in group B (p < 0.0001). A SRT shift was observed in group A, with no difference in group B, and a night shift in DPOAE-I/O in group B.ConclusionsReduced loudness tolerance is demonstrated during daytime hearing deprivation in contrast to nighttime; this may be due to increased central gain in the awake cortex. 相似文献
8.
Summary Background. Microsurgical selective adenomectomy is the best established method available for the treatment of Cushing's disease. However,
this surgical method warrants still more efforts to improve the results in minute microadenomas. In this paper the authors
evaluate a method of intraoperative cytological investigations during transsphenoidal surgery.
Method. Between January 1997 and September 1999, transsphenoidal surgery was performed in 75 patients with the diagnosis of Cushing's
disease. Fifty-one cases of proven microadenomas were reviewed.
Findings. Of 51 cases, 33 tumors were 3 mm or less in diameter, here after called minute adenomas. In 49 of 51 (96.1%) microadenomas,
adenoma tissue was identified by intraoperative cytological techniques. Postoperatively, only 35 of 51 ACTH-secreting microadenomas
(68.6%) were confirmed by immunostaining methods. This lower percentage was most probably due to the small amount of tissue
obtained. Therefore, in 14 cases (including 12 minute adenomas) the presence of the adenoma was only proven by cytological
preparation and clinical outcome. The sensitivity of cytological preparations in cases of confirmed Cushing's disease was
100%.
Interpretation. The method described here was particularly well suited for the intraoperative discrimination and documentation of minute
adenomas. Cytological preparation appears to be effective in improving the adenoma finding rate and the surgical outcome in
cases of Cushing's disease. 相似文献
9.
目的探讨6分钟步行试验(6MWT)对老年慢性心力衰竭(CHF)患者心功能的评价及其临床应用价值。方法54例CHF患者随机分为常规治疗组(n=29)和卡维地洛组(n=25),治疗前后进行步行试验及心功能分级的评定,监测白细胞介素6(IL-6)、去甲肾上腺素(NE)、心指数(CI)和左室射血分数(LVEF)。结果心功能Ⅳ级患者较Ⅲ级患者、Ⅳ级患者较Ⅱ级患者步行距离均明显下降(P〈0.01),而Ⅲ级与Ⅱ级患者之间步行距离的差异无显著性意义(P〉0.05);卡维地洛组6分钟步行距离治疗前后差异有显著性意义(P〈0.01),而治疗组差异无显著性意义(P〉0.05),并且步行距离与IL-6、NE呈显著负相关(P〈0.05),与LVEF和CI呈正相关(P〈0.05)。结论6MWT操作简单、易行、安全,结果可靠,可作为心衰患者心功能评估的方法,尤其适用于老年患者。 相似文献
10.