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41.
M F Stewart P Reed C Weinkove K J Moriarty A J Ralston 《Journal of clinical pathology》1993,46(3):280-282
The biochemical features of two patients with phaeochromocytomas illustrate the inadvisability of depending on a single group of analytes for the diagnosis. The first case presented as a surgical emergency with retroperitoneal haemorrhage. Biochemical diagnosis was difficult since total 24 hour urinary free catecholamine excretion was within normal limits in two out of three samples, and only marginally raised in the third with an atypical preponderance of adrenaline. Plasma catecholamine concentrations were also normal. But urinary excretion of the catecholamine metabolites, metadrenaline and 4-hydroxy-3-methoxy mandelic acid (HMMA), was consistently raised. In contrast, the second patient presenting with headache and labile hypertension showed normal metabolite excretion in the face of grossly increased free noradrenaline excretion and raised plasma noradrenaline concentrations. It is therefore recommend that, as well as urinary free catecholamines, one group of their main metabolites, the 3-methoxy amines (normetadrenaline and metadrenaline) or HMMA, should routinely be measured whenever a phaeochromocytoma is suspected. 相似文献
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Guus MJ Bökkerink Maja Joosten Erik Leijte Maud YA Lindeboom Ivo de Blaauw Sanne MBI Botden 《Journal of pediatric surgery》2021,56(3):465-470
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II. 相似文献
44.
María Jesús Fernández Aceñero MD PhD Cristina Díaz del Arco CDdA MD Carme Dinarés CD MD PhD Tania Labiano TL MD Eva Tejerina ET MD PhD Mª José Bernabé MJ B MD Elena Forcen EF MD Melchor Saiz-Pardo MSP MD Pablo Pérez PP MD Maria D. Lozano MDL MD PhD 《Diagnostic cytopathology》2023,51(1):26-35
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples. 相似文献
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Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
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N A Thacker A Jackson D Moriarty E Vokurka 《Journal of magnetic resonance imaging : JMRI》1999,10(4):582-588
This article shows that re-normalizing the interpolation kernel for a constant integral can make a significant improvement in performance of sinc interpolation methods. A comparison was performed between standard and re-normalized sinc kernels of various sizes using data from four commonly used magnetic resonance (MR) imaging sequences. Standard rotations were performed and compared with a "gold standard" data set generated by use of a large (13 x 13 x 13) sinc kernel. Measurements of systematic pixel intensity offset error and variance of generated residuals were used to estimate resultant interpolation error. Theoretical estimates of the consequent savings in computation time were compared with the measured time required for each algorithm and with the automated image registration (AIR) program. The use of a small (5 x 5 x 5) re-normalized kernel produced relative errors comparable to those in the gold standard data set, allowing saving in computation time of up to 30 times in comparison with standard sinc interpolation. This approach brings the implementation of MR volume re-slicing much closer to the demands of a clinical environment. J. Magn. Reson. Imaging 1999;10:582-588. 相似文献
49.
The effect of intravenous tenoxicam on pruritus in patients receiving epidural fentanyl 总被引:4,自引:0,他引:4
In this prospective randomised study, pruritus and pain were evaluated in patients undergoing abdominal surgery during which epidural fentanyl was administered. All patients had an epidural catheter inserted at the time of surgery. Epidural fentanyl 100 micrograms was administered intra-operatively and infused at a concentration of 2 micrograms.ml-1 for 48 h postoperatively. All patients received a standard anaesthetic and, in addition, the study group had a 20 mg bolus of tenoxicam intravenously, intra-operatively. Patients receiving tenoxicam demonstrated significantly lower pruritus and pain scores at 30 min, 2, 4, 8 and 24 h postoperatively as well as reduced pethidine requirements for breakthrough pain in the first 24 h. In conclusion, tenoxicam 20 mg significantly reduces the incidence and severity of postoperative pruritus in patients who received peri-operative epidural fentanyl. In addition, it significantly reduces pain and further analgesic requirements postoperatively. 相似文献
50.
The effect of an applied electric field on macrophage accumulation within the subacute spinal injury
Macrophages are implicated to play a substantive role in the acute inflammatory reaction to CNS insult in the delayed progressive secondary damage to parenchyma, espacially myelin. When placed in an electrical field in vitro, macrophages show directed pseudopodial extensions and migrate towards the positive pole (anode). We have evaluated if ED1 positive macrophage accumulations in rat spinal cord injuries were affected by the applied extracellular voltage, comparing their numbers to a sham treated group. Our hypothesis was that the applied voltage may reduce the concentration of phagocytes in the central injury and thus reduce the level of secondary damage produced by them. The applied voltage gradient did not alter the number or density of macrophage accumulations in the three week lesion, nor is there any difference in the degree of cavitation between control and experimental groups. 相似文献