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21.
We report on a 12-year old boy suffering from malignant epithelioid hemangioendothelioma of the liver, which is a very rare tumor in childhood. The tumor was detected by ultrasound examination at the age of 10 and appeared at that time as a solitary intrahepatic nodular lesion. During the following 2 years multiple nodular lesions developed in both hepatic lobes. There were neither any suspect anamnestic findings nor abnormal clinical or laboratory data. The tumor showed the typical histomorphological, immunohistochemical, and ultrastructural features of this entity, which is usually seen in older patients. We investigated proliferative activity, apoptotic regulation, and expression of VEGF and VEGF-receptor flk-1 by means of immunohistochemical techniques. According to the known slow growth activity of these tumors we found only a few Ki-67 positive tumor cells. We did not detect any apoptotic cells using TUNEL technique. The positive immunoreaction of the tumor cells with antibodies against VEGF and VEGF-receptor flk-1 may indicate the regulation of tumor growth by angiogenetic factors. We present our findings together with a summary of the most important publications of recent years concerning these tumors. 相似文献
22.
Flemming KD Wijdicks EF St Louis EK Li H 《Journal of neurology, neurosurgery, and psychiatry》1999,66(5):600-605
OBJECTIVE: To study the clinical course and determine predictors of deterioration in patients with lobar haemorrhages). METHODS: A comprehensive review of 61 consecutive patients with lobar haemorrhages was performed. Neurological deterioration was defined as (1) decrease in Glasgow coma sum score by 2 points, (2) new neurological deficit, or (3) clinical signs of brain herniation. A univariate logistic regression was performed and expressed in odds ratios. RESULTS: Sixteen of 61 (26%) patients with lobar haemorrhages deteriorated after admission. In a univariate analysis, only a Glasgow coma score <14 predicted deterioration (75% of deteriorators v 24% who did not deteriorate; p<0.0001). Initial CT characteristics predictive of deterioration included haemorrhage volume >60 ml (63% v 16%, p< 0.0001), shift of the septum pellucidum (75% v 36%, p<0.01), effacement of the contralateral ambient cistern (33% v 0%, p<0.0001), and widening of the contralateral temporal horn (50% v 0%, p<0.0001). Patients presenting and deteriorating within 12 hours of ictus declined due to enlargement of the haemorrhage. Those who deteriorated more than 12 hours after initial neurological symptoms, showed increased mass effect secondary to oedema. CONCLUSION-Patients with lobar haemorrhages presenting immediately after ictus are at risk for deterioration from enlargement of the haemorrhage and predictors of deterioration may be absent. Patients with large volume lobar haemorrhages presenting to the emergency department with decreased level of consciousness and shift on CT are at risk for further deterioration from worsening oedema. These patients require close observation and early aggressive management may be warranted. 相似文献
23.
F J Sasse D C Flemming B Hoff N T Smith I J Rampil 《Canadian Anaesthetists' Society journal》1979,26(5):420-423
A method of converting a Mapleson D (Bain) circuit to closed-circuit operation is presented, utilizing a laboratory air pump and a Waters carbon dioxide absorber canister to recirculate exhaled gas. The elimination of carbon dioxide from the circuit was studied and found to be adequate. The circuit would allow the use of low fresh gas flows for the maintenance of anaesthesia without the danger of carbon dioxide rebreathing. We suggest that such a circuit could provide appropriate conditions of gas humidity and temperature for endotracheal anaesthesia, while realizing the advantage of a circulator in mask anaesthesia is possible. Further design considerations for a "D circle" breathing system for clinical use are discussed. 相似文献
24.
Enchondroma and chondrosarcoma are two of the most commonly encountered primary bone lesions in the typical radiology practice. The purpose of this article is to review the clinical, radiological, and pathological features that distinguish conventional chondrosarcoma from enchondroma. Chondrosarcoma is almost always associated with pain and tends to present in the axial skeleton of middle aged adults. Enchondroma tends to present in young adults in the appendicular skeleton, particularly the hands, and is often an incidental finding. Although both lesions have characteristic radiographic appearances, difficulty separating these two entities most often occurs when a lesion is seen in the long tubular bones. The judicious use of computed tomography, magnetic resonance imaging, and nuclear medicine in conjunction with appropriate clinical data allows the radiologist to establish the correct diagnosis of benign or malignant medullary chondroid lesion in the majority of cases. 相似文献
25.
Lang H Thyen A Nadalin S Frerker M Moreno L Flemming P Martin M Oldhafer KJ Raab R 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》2000,32(1):1-10
Isolated hyperthermic perfusion of the liver was performed for 45 min in 27 pigs via hepatic artery and portal vein at mean inflow temperatures between 40.7 and 41.2 degrees C. In two study groups B and C (n = 9 pigs each) 50 microg recombinant human tumor necrosis factor-alpha (rhTNFalpha) per kg body weight were added to the perfusate, whereas in a control group A liver perfusion was done without rhTNFalpha. Before reperfusion the livers were washed out with Ringer's solution in all groups followed by a protein solution in group C. At 30 and 60 min after reperfusion the maximum systemic rhTNFalpha concentrations were significantly higher in group B with 68 and 61 ng/ml compared to 14.5 and 14.9 ng/ml in group C (p < 0. 05). Mean systemic porcine TNFalpha concentration was significantly higher in group B (217 pg/ml) compared to group C (50 pg/ml) 30 min after reperfusion (p = 0.012). Survival was 7/9 in group A and C and only 2/9 in group B with 6/7 pigs dying due to severe cardiopulmonary failure within 12 h after operation. In surviving pigs of group A and C only mild and transient hepatotoxicity was registered. The presented study underlines the feasibility of high dose rhTNFalpha application in an isolated hyperthermic liver perfusion system. Washout of the liver with a protein solution before reperfusion reduces systemic TNFalpha levels as well as associated lethal cardiocirculatory and hepatotoxic side effects. 相似文献
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28.
Our aim was to identify determinants of utilization of dental services among 20- to 34-year-old Danes as outlined in a conceptual framework. Our sample consisted of a sample of 464 individuals who had been interviewed by 10 experienced interviewers from The Danish National Institute of Social Research. Our questionnaire comprised a battery of questions based on our conceptual model. The analysis was done in a hierarchical manner using a framework with three steps: Predisposing factors → Enabling factors → Need factors → Utilization. Associations were evaluated with multivariate logistic regression analysis and expressed as odds ratios. The following factors were significantly associated with irregular use of dental services: age, sex, exercise habits, cost of dental treatment, dental anxiety, and perceived condition of teeth. Our findings suggest that a strategy aiming to increase young people's dental attendance should focus on the transition period—that is, when the youngsters leave the public dental health care system and have to make use of the private system. The strategy should also take into account that young men are more likely to become non-users. A concerted effort could be dedicated to the non-negligible group of individuals with dental anxiety and dental phobia. 相似文献
29.
Eric A.J. Bleeker Wim H. de Jong Robert E. Geertsma Monique Groenewold Evelyn H.W. Heugens Marjorie Koers-Jacquemijns Dik van de Meent Jan R. Popma Anton G. Rietveld Susan W.P. Wijnhoven Flemming R. Cassee Agnes G. Oomen 《Regulatory toxicology and pharmacology : RTP》2013,65(1):119-125
In recent years, an increasing number of applications and products containing or using nanomaterials have become available. This has raised concerns that some of these materials may introduce new risks for humans or the environment. A clear definition to discriminate nanomaterials from other materials is prerequisite to include provisions for nanomaterials in legislation. In October 2011 the European Commission published the ‘Recommendation on the definition of a nanomaterial’, primarily intended to provide unambiguous criteria to identify materials for which special regulatory provisions might apply, but also to promote consistency on the interpretation of the term ‘nanomaterial’. In this paper, the current status of various regulatory frameworks of the European Union with regard to nanomaterials is described, and major issues relevant for regulation of nanomaterials are discussed. This will contribute to better understanding the implications of the choices policy makers have to make in further regulation of nanomaterials. Potential issues that need to be addressed and areas of research in which science can contribute are indicated. These issues include awareness on situations in which nano-related risks may occur for materials that fall outside the definition, guidance and further development of measurement techniques, and dealing with changes during the life cycle. 相似文献
30.
Birgitte Mayland Havelund Flemming Brandt Sørensen John Pløen Jan Lindebjerg Karen‐Lise Garm Spindler Anders Jakobsen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(2):127-138
The aim of this study was to describe the dynamics of HIF‐1α, GLUT‐1, Bcl‐2 and Ki‐67 during chemoradiotherapy (CRT) of rectal cancer, and to investigate the fluctuation of these biomarkers in relation to pathological response to CRT. The study included 86 patients with rectal adenocarcinoma receiving preoperative CRT (>50.4 Gy and Uracil/Tegafur). Immunohistological expressions of HIF‐1α, GLUT‐1, Bcl‐2 and Ki‐67 were investigated in biopsies taken before treatment, after 2, 4 and 6 weeks of CRT and in specimens from the operation. Decreasing expressions of HIF‐1α, Bcl‐2 and Ki‐67 were observed during CRT, whereas GLUT‐1 overall was unchanged. No significant changes of the markers were observed in the interval between CRT and surgery. A significant association was observed between the presence of residual carcinoma after 6 weeks of treatment and pathological response to CRT, but no association was seen between the fluctuations of any of the markers and response to CRT. This unique material containing specimens before, after and during CRT for rectal cancer demonstrated biological dynamics in HIF‐1α, Bcl‐2 and Ki‐67, but not GLUT‐1, expression during CRT, and a significant association was seen between the presence of residual carcinoma after 6 weeks of treatment and pathological response to CRT. 相似文献