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791.
At this institution a new procedure has been developed that involves anastomosing one of the branches of the superficial temporal artery to one of the major trunks of the middle cerebral artery in the Sylvian fissure. This procedure has been performed in 22 cases to date. Clinical indications for this procedure have fallen into four major categories. This new type of anastomosis produces greater bypass flow than conventional cortical middle cerebral artery anastomoses, and may be a better therapeutic alternative in certain clinical situations. The preoperative and postoperative angiographic evaluation of these patients is discussed. The radiologic results in this series of patients are reviewed. 相似文献
792.
Cross JL Boulos S Shepherd KL Craig AJ Lee S Bakker AJ Knuckey NW Meloni BP 《Neuroscience research》2012,73(3):191-198
In this study we have assessed sodium-calcium exchanger (NCX) protein over-expression on cell viability in primary rat cortical neuronal and HEK293 cell cultures when subjected to oxygen-glucose deprivation (OGD). In cortical neuronal cultures, NCX2 and NCX3 over-expression was achieved using adenoviral vectors, and following OGD increased neuronal survival from ≈20% for control vector treated cultures to ≈80% for both NCX isoforms. In addition, we demonstrated that NCX2 and NCX3 over-expression in cortical neuronal cultures enables neurons to maintain intracellular calcium at significantly lower levels than control vector treated cultures when exposed to high (9mM) extracellular calcium challenge. Further assessment of NCX activity during OGD was performed using HEK293 cell lines generated to over-express NCX1, NCX2 or NCX3 isoforms. While it was shown that NCX isoform expression differed considerably in the different HEK293 cell lines, high levels of NCX over-expression was associated with increased resistance to OGD. Taken together, our findings show that high levels of NCX over-expression increases neuronal and HEK293 cell survival following OGD, improves calcium management in neuronal cultures and provides additional support for NCX as a therapeutic target to reduce ischemic brain injury. 相似文献
793.
OBJECTIVE: To determine safe and appropriate alarm limits for the Marquette 8000 pulse oximeter to prevent hyperoxic and hypoxic episodes in neonates. It is necessary to define these limits for each brand of oximeter because of the variance in nonuser adjustable calibration algorithms used in pulse oximeters. METHODOLOGY: Oxygen saturation values obtained from a Marquette 8000 pulse oximeter (SpO2) were compared with simultaneous arterial blood gas PaO2 values obtained from blood gas analysis, for 322 samples in 24 consecutive neonates (median 30 weeks' gestation). RESULTS: In order to prevent 95% of hyperoxic episodes (PaO2 > 90 mmHg), the upper alarm limit was 95% SpO2. Similarly, to prevent 95% of hypoxic episodes (PaO2 < 40 mmHg), the lower alarm limit was 95% SpO2. A sensitivity lower than 95% had to be accepted to develop an alarm range which prevented both hyperoxic and hypoxic episodes. To maintain PaO2 values between 40 and 90 mmHg, an appropriate alarm range of 94-97% SpO2 (90% sensitivity, 28% specificity) was established. CONCLUSIONS: The relative merits of high sensitivity versus high specificity should be considered when determining appropriate alarm limits. Alarm limits which represent a balance between sensitivity and specificity will minimise false alarms and provide a clinically practical range. It would be useful for this type of information to be available for each brand of oximeter, to assist the user in determining appropriate alarm settings. 相似文献
794.
Recurrent abdominal pain and Helicobacter pylori in a community-based sample of London children 总被引:2,自引:0,他引:2
JM O'Donohoe PB Sullivan R Scott T Rogers MJ Brueton D Barltrop 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(8):961-964
Helicobacter pylori is accepted as an important factor in the pathogenesis of peptic ulcer disease. Infection is probably most commonly acquired in early life but there is still limited information on the prevalence or symptomatology of H. pylori infection in childhood. The aim of the present study was to establish the prevalence of H. pylori infection in a large sample of urban school children and to determine its relationship, if any, to a history of recurrent abdominal pain. Using a commercial ELISA significant levels of anti- H , pylori IgG antibody were detected in 107/640 (16.7%) of school children (M, 383; F, 257; mean age 9.15 years, range 4-13). No relationship was demonstrated between H. pylori seropositivity and a personal or family history of recurrent abdominal pain or the nature of the pain. 相似文献
795.
796.
Jean‐Pierre Raynauld Chris Buckland‐Wright Rupert Ward Denis Choquette Boulos Haraoui Johanne Martel‐Pelletier Imad Uthman Visithan Khy Jean‐Luc Tremblay Carole Bertrand Jean‐Pierre Pelletier 《Arthritis \u0026amp; Rheumatology》2003,48(2):370-377