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111.
Dual-energy digital subtraction chest radiography: technical considerations   总被引:10,自引:0,他引:10  
In the evaluation of asbestos-related pulmonary and pleural abnormalities, conventional chest radiography has been shown to have a low sensitivity for the detection of lung nodules and subtle interstitial disease. Pleural plaques may simulate pulmonary nodules, and interstitial processes can be masked by adjacent pleural abnormalities. Dual-energy digital subtraction chest radiography may enable investigators to characterize asbestos-related pulmonary and pleural abnormalities with greater accuracy. "Soft-tissue" images, designed to remove pleural calcifications, may allow for better evaluation of the lung parenchyma. "Bone" images, designed to remove soft-tissue structures, may enhance the detection of pleural calcifications. In this pictorial essay we illustrate the methods, technical considerations, and limitations of dual-energy digital subtraction chest radiography performed with global subtraction weighting factors.  相似文献   
112.
Optic nerve head swelling is caused by either ocular or systemic diseases of inflammatory, infective, infiltrative, compressive, or ischemic origin. Uncommonly, an isolated optic nerve head swelling without the above underlying mechanisms might also occur. Two patients presented with unilateral, isolated optic nerve head swelling. A detailed oculoneurological examination and a series of investigations failed to indicate any pathology. No probable cause for optic nerve head swelling in these patients was determined by the authors. the authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or privider of services discussed in this article. The authors also do not discuss the use of off-label products, which include unlabeled, unapproved, or investigative products or devices.  相似文献   
113.
Summary Anthropometric measurements comprising height, weight, sitting height, arm span, horizontal, vertical and circumferential chest dimensions, taken in 255 school boys from a lower middle class urban population were statistically analysed. The data have been tabulated, and the interrelationships between the various measurements examined and discussed. From the Department of Physiology, Kilpauk Medical College, Madras—10.  相似文献   
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Limiting the number of oocytes transferred at gamete intra-Fallopiantransfer (GIFT) has limited the incidence of high-order pregnancybut at the same time compromised the fertility potential ofsome patients. A review of 300 patients who have undergone GIFTusing a flexible approach as to the number of oocytes transferredidentifies the patients at risk of high-order pregnancy as thoseaged under 30 years hi whom more than six oocytes are returnedand whose partner's spermatozoa have high progressive motUity.  相似文献   
116.
Lyle P  Evans R  Jarboe E  Fong D  Behbakht K  Davidson S  Singh M 《Oncology (Williston Park, N.Y.)》2005,19(9):1178, 1183, 1188, 1190, 1195-1178, 1183, 1188, 116 passim
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117.
This article reviews CT and MRI features of malignant cardiac and pericardial tumors, most of which originate from the lung, breast, melanoma, leukemia, or lymphoma through lymphatic, hematogenous, transvenous, and direct pathways. Although echocardiography establishes the diagnosis in most cases, CT and MRI provide additional physical, spatial, and functional information that further aids the evaluation of metastases. For instance, CT provides superior resolution for detecting calcification or fat, while MRI with its direct multiplanar ability more completely characterizes the heart, pericardium, mediastinum, and lungs. MRI also helps elucidate the pathophysiological effects of these tumors on cardiac function through gated cine-loop sequences. Beyond tumor characterization, both modalities can help confirm diagnosis through the addition of contrast, which helps distinguish tumor from myocardium, thrombus, and blood flow artifact. Ultimately, MRI best facilitates surgical planning and posttreatment follow-up in large part because of its unparalleled ability to locate and delimit these tumors.  相似文献   
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HACS1 is a Src homology 3 and sterile alpha motif domain-containing adaptor that is preferentially expressed in normal hematopoietic tissues and malignancies including myeloid leukemia, lymphoma, and myeloma. Microarray data showed HACS1 expression is up-regulated in activated human B cells treated with interleukin (IL)-4, CD40L, and anti-immunoglobulin (Ig)M and clustered with genes involved in signaling, including TNF receptor-associated protein 1, signaling lymphocytic activation molecule, IL-6, and DEC205. Immunoblot analysis demonstrated that HACS1 is up-regulated by IL-4, IL-13, anti-IgM, and anti-CD40 in human peripheral blood B cells. In murine spleen B cells, Hacs1 can also be up-regulated by lipopolysaccharide but not IL-13. Induction of Hacs1 by IL-4 is dependent on Stat6 signaling and can also be impaired by inhibitors of phosphatidylinositol 3-kinase, protein kinase C, and nuclear factor kappaB. HACS1 associates with tyrosine-phosphorylated proteins after B cell activation and binds in vitro to the inhibitory molecule paired Ig-like receptor B. Overexpression of HACS1 in murine spleen B cells resulted in a down-regulation of the activation marker CD23 and enhancement of CD138 expression, IgM secretion, and Xbp-1 expression. Knock down of HACS1 in a human B lymphoma cell line by small interfering ribonucleic acid did not significantly change IL-4-stimulated B cell proliferation. Our study demonstrates that HACS1 is up-regulated by B cell activation signals and is a participant in B cell activation and differentiation.  相似文献   
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