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排序方式: 共有917条查询结果,搜索用时 15 毫秒
1.
Michelle Linda Ferderbar Thomas E. Doyle Reza Samavi David Koff 《Journal l'Association canadienne des radiologistes》2019,70(2):119-124
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization. 相似文献
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This study examined the expression and perception of facial emotion in patients with unilateral cerebrovascular pathology. Subjects were 12 right brain-damaged (RBD), 15 left brain-damaged (LBD) aphasic, and 16 normal control (NC) right-handed males. Expressions were elicited during posed and spontaneous conditions. Both positive and negative emotions were studied. RBDs were significantly impaired, relative to LBDs and NCs, in expressing and perceiving facial emotion. There were no group differences as a function of condition, but there were differences as a function of emotional valence. Qualitative performance differences also were observed. There was no evidence that the ability to produce a particular emotion was related to the ability to identify the same emotion. Overall, these findings support the notion that the right cerebral hemisphere is dominant for expressing and perceiving facial emotion. 相似文献
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S. J. Carbognin N. M. Solomon F. E. Yeo S. J. Swanson E. M. Bohen J. M. Koff S. G. Sabnis K. C. Abbott 《American journal of transplantation》2006,6(7):1746-1751
Interferon alpha (IFN-alpha) can be effective therapy for patients with chronic kidney disease who have chronic hepatitis C (HCV). However, acute allograft rejection has been reported in association with IFN-alpha following kidney transplantation, and therefore IFN therapy is recommended prior to, rather than after, kidney transplantation whenever feasible. The special case of repeat allograft recipients who contract HCV after the first transplantation presents special difficulties. This report features the case of a repeat allograft recipient who presented with neutropenic fevers after 5 months of pegylated IFN-alpha therapy, initiated 6 months following the functional loss of his third graft and the reinitiation of hemodialysis (HD). Physical exam, radiographic and laboratory findings led to allograft nephrectomy. The pathologic findings supported a diagnosis of acute-on-chronic rejection. This represents a rare case of IFN-alpha induced rejection following allograft failure and return to HD in a repeat allograft recipient. It also calls attention to the need for a high index of suspicion for the development of allograft rejection, which may require allograft nephrectomy even after allograft 'failure'. 相似文献
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Summary The content of these papers has been heavily weighted towards reconstructions performed utilizing segments of stomach. This was not done to place a value judgment on this type of reconstruction, rather it helps establish an awareness of: (1) potentially serious metabolic and gastrointestinal complications not previously reported in children and (2) particularly frequent symptomatic disturbances collectively included in the hematuria-dysuria syndrome. Recognition of problems specifically associated with a certain type of intestinal segment, as well as complications generally accompanying any form of intestinal reconstruction, will hopefully provide pediatric urologists and nephrologists with a better understanding of the issues that must be addressed in using these newer surgical techniques and focus attention on the specific indications and contraindications for incorporating intestinal segments into the urinary tract. Although long-term follow-up information still remains sparse, it appears that regular surveillance programs are required and both pediatric nephrologists and urologists need to be part of these programs. 相似文献
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AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice. 相似文献