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961.
Verbal Working Memory and Atherosclerosis in Patients with Cardiovascular Disease: An fMRI study 总被引:1,自引:0,他引:1
Andreana P. Haley PhD Lawrence H. Sweet PhD John Gunstad PhD Daniel E. Forman MD Athena Poppas MD Robert H. Paul PhD David F. Tate PhD Ronald A. Cohen PhD 《Journal of neuroimaging》2007,17(3):227-233
BACKGROUND AND PURPOSE: Intimal-medial thickening (IMT) of the carotid wall is an accepted peripheral marker of atherosclerosis. It is associated with increased risk for myocardial infarction and stroke, and lower attention-executive-psychomotor functioning. The purpose of this study was to examine the relationship between IMT and brain activity during a verbal working memory (VWM) task in patients with cardiovascular disease (CVD). METHODS: Thirteen CVD patients underwent functional magnetic resonance imaging (fMRI) during a 2-Back VWM task, and B-mode ultrasound of the carotid arteries. IMT was calculated using an automated algorithm based on a validated edge-detection technique. The relationship between IMT and 2-Back-related brain activity was modeled using partial correlations controlling for age and small vessel disease as measured by white matter signal hyperintensities on MRI (WMH). RESULTS: Higher IMT was associated with lower 2-Back-related signal intensity and in the right middle frontal gyrus, independent of age and WMH. CONCLUSIONS: IMT may be one mechanism contributing to brain dysfunction in CVD. The blood oxygenation level-dependent (BOLD) contrast appears to be highly sensitive to peripheral vascular health as measured by IMT. Future studies should examine the sensitivity and specificity of the BOLD response for predicting cognitive decline in CVD. 相似文献
962.
Enhanced hemolysis in pediatric patients requiring extracorporeal membrane oxygenation and continuous renal replacement therapy 总被引:1,自引:0,他引:1
Christopher Betrus Robert Remenapp John Charpie Timothy Kudelka Patrick Brophy William E Smoyer Jen-Jar Lin 《Annals of thoracic and cardiovascular surgery》2007,13(6):378-383
PURPOSE: Hemolysis during extracorporeal membrane oxygenation (ECMO) may be associated with the development of hemoglobinuria (Hb) nephropathy and acute renal failure. For patients requiring ECMO, continuous renal replacement therapy (CRRT) can be simultaneously performed by attaching a hemofilter to the ECMO circuit, thereby shunting part of the ECMO blood flow through the hemofilter. However, the possibility that CRRT may further enhance hemolysis (and the risk of Hb nephropathy) in patients on ECMO has not been previously investigated. METHODS: Medical records of 42 children (1 day-12 years old) who required ECMO (ECMO group, n=25) or ECMO and CRRT (ECMO+CRRT group, n=17) after cardiac surgery were reviewed. RESULTS: Forty-one out of 42 patients had elevated plasma-free hemoglobin (FHb) on the first day of ECMO. For all subjects, peak change (mean+/-SD) in FHb (Peak%C-FHb, 83.6+/-183%) correlated with serum lactic dehydrogenase (150+/-324%, r=0.49, p<0.05) and marginally with ECMO blood flow rate (BFR) (Peak%C-BFR, 36.8+/-51.0%, r=0.29, p=0.06). Compared with the ECMO group, the ECMO+CRRT group had a higher Peak%C-FHb (160+/-259%, p<0.05) and Peak%C-BFR (62+/-64%, p<0.05). Also, there was a significant increase in FHb one day after the initiation of CRRT compared with the level prior to CRRT (73.3+/-49.2 vs. 50.0+/-30.3 mg/dL, respectively, p=0.012). Serum creatinine (but not blood urea nitrogen) was significantly higher in the ECMO+CRRT group compared with the ECMO group. The percent change in serum creatinine during ECMO did not correlate with Peak%C-FHb in the ECMO group. CONCLUSION: Our findings suggest that there is enhanced hemolysis during combined ECMO and CRRT compared with ECMO alone. However, the clinical impact of increased hemolysis on renal function in patients receiving ECMO with or without CRRT remains to be determined. 相似文献
963.
Parish P Sedghizadeh Derek Wong Charles F Shuler Vincent Linz John R Kalmar Carl M Allen 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e30-e34
The calcifying epithelial odontogenic tumor (CEOT), or Pindborg tumor, is a rare and benign odontogenic neoplasm that affects the jaw. The most common manifestation of CEOT is a unifocal or localized lesion of the involved jaw, which may appear clinically as a hard tissue swelling and radiographically as a mixed radiolucent-radiopaque mass. In this article, we present a unique case of CEOT affecting multiple sites in the maxilla and mandible of a 51-year-old white man. Though biopsy samples from all involved sites revealed similar histopathologic features consistent with CEOT, the fact that there was a multifocal presentation is an unusual phenomenon for CEOT and has never been reported. Multifocal odontogenic lesions are not typical but have been observed in conditions associated with known genetic mutations. For example, multiple odontogenic keratocysts are the most common feature of the inherited condition known as nevoid basal cell carcinoma syndrome. This case, however, is the first one to demonstrate that there may be a multifocal variant of CEOT that has not been previously recognized. 相似文献
964.
965.
966.
967.
Although only recently introduced, chemically-modified hyaluronic acid dermal fillers have gained widespread acceptance as “redefining” dermal fillers in the fields of dermatology and cosmetic facial surgery. Although hyaluronic acid-based dermal fillers have a low overall incidence of long term side effects, occasional adverse outcomes, ranging from chronic lymphoplasmacytic inflammatory reactions to classic foreign body-type granulomatous reactions have been documented. These long-term adverse events are reviewed. 相似文献
968.
Jennifer Tucker Ammon John Nyland Haw Chong Chang Robert Burden David N. M. Caborn 《Knee surgery, sports traumatology, arthroscopy》2007,15(11):1375-1381
This in vitro biomechanical study used cadaveric specimens to compare the rotator cuff repair fixation provided by BioCorkscrew
and Bioknotless RC suture anchors. Three cm wide by 1-cm long full-thickness supraspinatus defects were repaired using either
two BioCorkscrew suture anchors with combined vertical and horizontal mattress sutures (n = 7) or three Bioknotless RC suture anchors with simple sutures (n = 7). Therefore, the BioCorkscrew suture anchor group had two sutures per anchor (four total sutures), while the Bioknotless
RC suture anchor group had one suture per anchor (three total sutures). Two-phase cyclic (5–100 N, 1,000 cycles and 5–180 N,
2,000 cycles) and load to failure tests (31 mm/s) were performed. Non-parametric statistics were used to compare group differences
(P < 0.05). All of the BioCorkscrew group specimens (seven of seven) completed the two phase cyclic test regimen without failure
or gapping ≥ 5 mm, compared to only three of seven of the Bioknotless RC group (Fisher’s Exact test = 0.03). Groups did not
differ for repair site gapping during the 5–100 N cyclic test phase (Fisher’s Exact test = 0.77), however more of the Bioknotless
RC group displayed gapping ≥ 5 mm during the 5–180 N cyclic test phase than the BioCorkscrew group (P = 0.02). The BioCorkscrew group also displayed greater yield load during load to failure testing (492.2 ± 204 N vs. 296.4 ± 155 N,
P = 0.03). In this in vitro biomechanical study, the BioCorkscrew group with combined vertical and horizontal mattress sutures
displayed greater cyclic test survival, less repair site gapping, and superior yield load compared to the Bioknotless RC group
with simple sutures. These results in human cadaveric rotator cuff-humerus specimens suggest better immediate post-operative
repair site strength and a reduced need for post-operative restrictions. Clinical studies are needed to determine how these
rotator cuff repair modes withstand the forces of early rehabilitation and activities of daily living that potentially influence
patient outcomes. 相似文献
969.
Arto J. Turunen José A. Fernández Leena Lindgren Kaija T. Salmela Lauri E. Kyllönen Heikki Mäkisalo John H. Griffin Sanna M. Siitonen Jari Petäjä Eero J. Pesonen 《American journal of transplantation》2005,5(9):2204-2212
We studied the role of endogenous activated protein C (APC), the major physiological anti-coagulant with concomitant anti-inflammatory properties, on ischemia/reperfusion (I/R) in 45 patients participating in a larger trial comparing three immunosuppressive protocols in cadaveric renal transplantation: perioperative anti-thymocyte globulin (ATG, Fresenius AG, Bad Homburg, Germany), perioperative basiliximab and conventional triple therapy. Blood samples for assessing plasma APC, protein C, and lactoferrin concentrations, neutrophil CD11b and L-selectin expressions and blood leukocyte differential counts were obtained preoperatively and before reperfusion from central venous cannula, complemented with simultaneous samples from iliac artery and graft vein for calculation of transrenal differences (Delta) of study parameters at 1 and 5 min after reperfusion. Unlike basiliximab or conventional therapy groups, ATG infusion induced a substantial increase in plasma APC concentration (119 [88-144]% before infusion vs. 232 [85-1246]% after infusion, p<0.001), resulting in renal graft sequestration of APC at 1 min after reperfusion (Delta=-72 [-567 to 12]%, p<0.001). Graft APC consumption was associated with transrenal reduction of neutrophil activation markers (L-selectin r=0.7, p=0.01; lactoferrin r=-0.6, p=0.02; CD11b r=-0.8, p=0.001), and with both warm (r=0.6, p=0.01) and cold ischemia time (r=0.6, p=0.02) and donor age (r=0.6, p=0.01). These findings suggest that APC has an anti-inflammatory role in I/R injury in clinical renal transplantation. 相似文献
970.
The techniques for revascularization in the neurocranium, skull base, and neck continue to evolve at an exciting pace. In this body of literature, however, techniques for harvesting radial artery and saphenous vein grafts are mainly reported using traditional open techniques. Minimally invasive procedures are fast becoming an alternative to open techniques in many fields and have the potential to become the standard of care. The cardiovascular literature is replete with reports of endoscopically harvested vascular grafts. This article reviews both methods, since the current state of the art involves knowledge of open and endoscopic harvesting techniques. 相似文献