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排序方式: 共有861条查询结果,搜索用时 16 毫秒
41.
Katerina Aligizaki Panagiota Katikou Georgios Nikolaidis Alexandra Panou 《Toxicon》2008,51(3):418-427
In order to investigate the toxicity of Ostreopsis species present in Greek coastal waters, cultures of Ostreopsis sp. and Ostreopsis ovata, mixed Ostreopsis field populations and shellfish collected from coastal waters of North Aegean Sea during late summer and autumn periods of 2004, 2005 and 2006 were examined by both mouse bioassay (MBA) and hemolysis neutralization assay (HNA). MBA testing was based on two different extraction protocols, while HNA also included the use of ouabain, a known palytoxin (PLT) antagonist. Results indicated the presence of a compound in both Ostreopsis cells and shellfish tissues, which was strongly toxic to mice. This compound exhibited characteristic symptomatology in mice (death, numbness, waddling gait and blindness) to that of PLT, as well as delayed hemolytic activity, which was neutralized by ouabain. HNA indicated that Ostreopsis cells contained a PLT-like compound (putative PLT, p-PLT) at concentrations ranging between 0.4 and 0.9 pg/cell, whereas concentration in shellfish tissues was estimated to range from about 33.3 to 97.0 microg p-PLT/kg tissue. To our knowledge, this is the first report of p-PLT contamination of shellfish by natural Ostreopsis species populations in European coastal waters and possibly globally, and also the first evidence on Ostreopsis cells' toxicity in the Eastern Mediterranean Sea. 相似文献
42.
M Stronati MG Revello RM Cerbo M Furione G Rondini G Gerna 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(3):340-341
43.
KP Morris JR Skinner C Wren S Hunter MG Coulthard 《Archives of disease in childhood》1993,68(5):637-643
Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities. 相似文献
44.
Economopoulos T Dimopoulos MA Foudoulakis A Nikolaidis C Tsatalas C Pectacides D Rontogianni D Papageorgiou E Fountzilas G 《Leukemia research》2000,24(12):1652-998
Non-African Burkitt's lymphoma is a rare disease among adults without AIDS. Among 1352 Greek adult patients with non-Hodgkin's lymphoma, 24 cases (1.8%) were classified as Burkitt's (BL) or Burkitt-like (BLL) lymphoma. Eleven cases fulfilled the criteria of BL and 13 of BLL. No statistical differences were found in the general characteristics of the two groups at the time of diagnosis. Extranodal involvement was a common finding in both groups and bulky disease (>10 cm) was observed in almost one half of the patients. The majority of the patients were treated with intensive, although different, protocols. After induction treatment, complete remission (CR) was achieved in 14 patients (60.8%). CR was reached in all cases with stage I–II, while in stage IV the CR rate was 30.4%. The median overall survival was 27 months. The median survival for BL was 13 months compared to 27 months in the BLL group (P=0.34). The data of the present retrospective analysis, indicated that there were not significant clinical differences between BL and BLL variants. Since BLL is still a non-reproducible category in the REAL classification, all BL variants must be treated uniformly with intensive protocols. 相似文献
45.
46.
Noncontrast helical CT for ureteral stones 总被引:1,自引:0,他引:1
Illya C. Boridy Paul Nikolaidis Akira Kawashima Carl M. Sandler Stanford M. Goldman 《World journal of urology》1998,16(1):18-21
Noncontrast helical computed tomography (CT) has recently been found to be superior to excretory urography (IVU) in the evaluation
of patients with suspected ureterolithiasis. Noncontrast helical CT does not require the use of intravenous contrast material
with its associated cost and risk of adverse reactions and can be completed within 5 min, in most cases. Noncontrast CT often
detects extraurinary pathology responsible for the patient's symptoms. CT is also more sensitive than IVU in detecting the
calculus, regardless of its size, location, and chemical composition. However, confidently differentiating ureteral calculi
from phleboliths along the course of the ureter may, at times, be difficult. The “tissue-rim” sign, a rim of soft tissue attenuation
around the suspicious calcification, is helpful in making this distinction. Noncontrast CT does not provide physiological
information about renal function and the degree of obstruction. A pilot study has suggested a proportional relationship between
the extent of perinephric edema and the degree of obstruction. The cost of the examination and the radiation dose delivered
to the patient may be higher with CT. Despite these limitations, noncontrast helical CT has quickly become the imaging study
of choice in evaluating patients with acute flank pain. 相似文献
47.
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury. 相似文献
48.
Computed tomography of the pancreas 总被引:2,自引:0,他引:2
49.
Background
Chronic lymphocytic leukemia (CLL) is a monoclonal disorder, characterized by a progressive proliferation of functionally incompetent B lymphocytes. There is increased evidence of association between CLL and skin cancers, including the uncommon Merkel cell carcinoma (MCC). 相似文献50.
Nikolaidis P vanSonnenberg E Haddad ZK Chen YH Zou KH Tuncali K Silverman SG 《Academic radiology》2005,12(11):1475-1482
RATIONALE AND OBJECTIVES: To determine and analyze the patterns of practice of nonvascular interventional procedures in academic centers in the United States. MATERIALS AND METHODS: A survey was administered via e-mail to the chief residents of 112 academic radiology departments in the United States. Recipients of the survey were asked to identify which sections within their respective radiology departments performed each of 43 types of nonvascular interventional procedures. An additional entry for performance of procedures by non-radiologists was provided. A total of 66 (59%) recipients responded. The statistical method used was the analysis of contingency tables. RESULTS: Percutaneous abdominal biopsies are performed mainly by abdominal and body imaging sections (43/66, 65%), followed by vascular/interventional sections (21/66, 32%). Percutaneous abdominal drainages are performed mostly by abdominal, body imaging, and computed tomography sections (40/66, 61%), followed by vascular/interventional sections. Fluoroscopically guided procedures were performed most commonly by vascular/interventional sections, including percutaneous gastrostomy (40/66, 61%), percutaneous nephrostomy (42/66, 64%), and biliary interventions such as percutaneous transhepatic cholangiography (47/66, 71%). Breast and musculoskeletal procedures are performed by their respective sections most frequently. Non-radiologists perform a significant portion of certain types of procedures: paracenteses, thoracenteses, biliary interventions (particularly stone extractions), enterostomies (particularly percutaneous jejunostomies and cecostomies), and certain biopsies (kidney and prostate). CONCLUSIONS: Academic US radiology sections perform nonvascular interventional radiology procedures in a complex and nonuniform manner. The vascular/interventional sections and organ system and modality (especially CT) sections perform the bulk of the procedures included in the survey. Breast imaging sections predominate in procedures in their disciplines. A substantial number and amount of interventional radiology procedures are performed by non-radiologists. 相似文献