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101.
Manuel Garcia Ruiz Alvin Garcia Chaves Carlos Ruiz Iba?ez Jorge Mario Gutierrez Mazo Juan Carlos Ramirez Giraldo Alejandro Pelaez Echavarria Edison Valencia Diaz Gustavo Pelaez Restrepo Edwin Nelson Montoya Munera Bernardo Garcia Loaiza Sebastian Gomez Gonzalez 《Journal of digital imaging》2011,24(2):271-283
This paper presents the mantisGRID project, an interinstitutional initiative from Colombian medical and academic centers aiming to provide medical grid services for Colombia and Latin America. The mantisGRID is a GRID platform, based on open source grid infrastructure that provides the necessary services to access and exchange medical images and associated information following digital imaging and communications in medicine (DICOM) and health level 7 standards. The paper focuses first on the data abstraction architecture, which is achieved via Open Grid Services Architecture Data Access and Integration (OGSA-DAI) services and supported by the Globus Toolkit. The grid currently uses a 30-Mb bandwidth of the Colombian High Technology Academic Network, RENATA, connected to Internet 2. It also includes a discussion on the relational database created to handle the DICOM objects that were represented using Extensible Markup Language Schema documents, as well as other features implemented such as data security, user authentication, and patient confidentiality. Grid performance was tested using the three current operative nodes and the results demonstrated comparable query times between the mantisGRID (OGSA-DAI) and Distributed mySQL databases, especially for a large number of records. 相似文献
102.
103.
van Engen Catherine E Ofman Rob Dijkstra Inge ME Schackmann Martin J Wanders Ronald JA Kemp Stephan 《Tijdschrift voor kindergeneeskunde》2013,81(1):10-10
Tijdschrift voor Kindergeneeskunde - 相似文献
104.
Suk Yun Kang MD PhD Toshiaki Wasaka PhD Ejaz A. Shamim MD Sungyoung Auh PhD Yoshino Ueki MD PhD Grisel J. Lopez MD Tetsuo Kida PhD Seung‐Hyun Jin PhD Nguyet Dang ME Mark Hallett MD 《Movement disorders》2010,25(13):2148-2155
The sequence effect (SE) in Parkinson's disease (PD) is progressive slowing of sequential movements. It is a feature of bradykinesia, but is separate from a general slowness without deterioration over time. It is commonly seen in PD, but its physiology is unclear. We measured general slowness and the SE separately with a computer‐based, modified Purdue pegboard in 11 patients with advanced PD. We conducted a placebo‐controlled, four‐way crossover study to learn whether levodopa and repetitive transcranial magnetic stimulation (rTMS) could improve general slowness or the SE. We also examined the correlation between the SE and clinical fatigue. Levodopa alone and rTMS alone improved general slowness, but rTMS showed no additive effect on levodopa. Levodopa alone, rTMS alone, and their combination did not alleviate the SE. There was no correlation between the SE and fatigue. This study suggests that dopaminergic dysfunction and abnormal motor cortex excitability are not the relevant mechanisms for the SE. Additionally, the SE is not a component of clinical fatigue. Further work is needed to establish the physiology and clinical relevance of the SE. © 2010 Movement Disorder Society. 相似文献
105.
106.
ME Penny 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(S383):114-120
It has been suggested that proliferation of enterobacteriaceae and/or anaerobes in the duodenum of some children with acute diarrhoea determines whether the episode becomes persistent. A review of published studies and the comparison of cultures of duodenal aspirates from Peruvian children with acute and persistent diarrhoea and diarrhoea-free children did not support this hypothesis. Although many children had enterobacteriaceae and/or anaerobes cultured there was no correlation with clinical and nutritional outcome. Age, nutritional status, the environment and the aetiology of the episode were determinants of the duodenal microflora independent of diarrhoea. Culture of the duodenal aspirates did not increase the yield of enteropathogens which were isolated more frequently from stools than from the duodenum. Despite the presence of a single strain or serotype of enterobacteriaceae suggesting that these bacteria were colonizing the duodenum, we were unable to demonstrate any adherence mechanisms in the majority of them. Two often bacteria with no other evidence of virulence caused diarrhoea in the RITARD rabbit model. 相似文献
107.
Treasure T Valencia O Sherlaw-Johnson C Gallivan S 《Health care management science》2002,5(4):243-248
The need for effective surgical performance measurement has gained an increasingly high profile in recent years, particularly since events at Bristol Royal Infirmary, where apparent poor performance has prompted the UK Department of Health to instigate a major Public Inquiry. This paper describes issues that concern the measuring and monitoring of surgical performance, and methods that have been devised for judging a good surgeon from the less competent. The authors are a collaborative team composed of specialists in Cardiothoracic surgery and Operational Research analysts with experience of monitoring performance in cardiac surgery. This paper describes concrete examples from that knowledge base. 相似文献
108.
Impact of oral L-glutamine on glutathione, glutamine, and glutamate blood levels in volunteers 总被引:4,自引:0,他引:4
OBJECTIVE: We investigated the effect of glutamine supplementation on plasma glutamine (Gln), glutamate (Glu), and whole-blood glutathione (GSH) concentrations in human volunteers. METHODS: Subjects first adapted to a standard diet with known intakes of protein, total GSH, cysteine, methionine, and total Glu (Glu values include Glu and Gln) for 3 d. Plasma Gln, Glu, and whole-blood GSH levels were then measured at 4-h intervals over 24 h. Supplemental oral Gln (0.3 g x kg(-1) x d(-1)) was ingested for 10 d and then 24-h plasma levels of Gln, Glu, and whole-blood GSH were measured. RESULTS: The plasma concentrations of Glu (116%; P = 0.006) and Gln (20%; P = 0.046) were significantly higher, whereas concentrations of GSH were significantly lower (37%; P = 0.00091) after oral Gln supplementation. CONCLUSION: Oral Gln increases Glu and Gln levels in plasma of healthy subjects but does not increase GSH red cell (whole-blood) levels. Thus, GSH biosynthesis and preservation of GHS stores in red blood cells may involve rate-limiting substrates other than Gln. 相似文献
109.
Fibrinogen and the amount of leukoaraiosis in patients with symptomatic small-vessel disease 总被引:1,自引:0,他引:1
Martí-Fàbregas J Valencia C Pujol J García-Sánchez C Martí-Vilalta JL 《European neurology》2002,48(4):185-190
We investigated whether there is a direct correlation between plasma fibrinogen levels and the amount of leukoaraiosis (LA) in patients with symptomatic small-vessel disease. The study included 28 patients: 12 with a first-ever lacunar infarction (LI) and 16 with Binswanger's disease (BD). The mean age was 71 years (SD 8.6), and 21 were men. For each patient, we recorded demographic data, vascular risk factors and the results of blood chemistry analysis including fibrinogen (g/l), hematocrit (decimal fraction) and total serum proteins (g/l). A cerebral MR scan was performed in each patient and an LA score was obtained by an investigator blind to clinical data, using a semiquantified scale in six areas of each cerebral hemisphere (0-4 points in each area, total scoring range 0-48 points). RESULTS: The mean (SD) for the LA score was 18.9 (10.7) and for plasma fibrinogen 3.97 (1.1). Pearson's and Spearman's correlation coefficients between fibrinogen and LA score were 0.43 (p = 0.02) and 0.49 (p = 0.007), respectively. Multiple-regression analysis between groups (LI or BD) and fibrinogen versus LA score showed the strongest association for the BD group (p = 0.014) and a direct relation with fibrinogen (p = 0.018). No statistically significant association was found between LA score and age, sex, any vascular risk factor, hematocrit or total serum protein. CONCLUSION: There is a significant correlation between plasma fibrinogen levels and the amount of LA in patients with symptomatic cerebral small-vessel disease. This result suggests that fibrinogen may be involved in the pathophysiology of LA in these patients. 相似文献
110.
Eduardo Vásquez Gutiérrez Carlos Alberto Calderón Elvir José Manuel Ruano Aguilar José Antonio Gutiérrez Ureña Juan Carlos Duarte Valencia Carlos Alejandro Leal y Leal 《Clinical & translational oncology》2002,4(9):501-505
Undifferentiated embryonal hepatic sarcoma is the third most frequent malignant hepatic neoplasm in children. We describe two cases of school age who presented with dyspnea, weight loss, epigastric pain and a large palpable mass in the right hepatic lobe in the absence of tumor markers. An ultrasound showed a solid mass and the computed tomography, mixed well limited cystic images. Surgical treatment was a right hemihepatectomy and the use of chemotherapy. An undifferentiated embryonal hepatic sarcoma is a diagnostic possibility in school age children presenting with large hepatic mass and negative tumor markers. The initial treatment is a complete tumor resection and chemotherapy in order to increase survival. 相似文献