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61.
Decreased inhibition by gravidin of arachidonate release from transformed compared to nontransformed cells. 下载免费PDF全文
1. Gravidin (a phospholipase A2 inhibitor) reduced the release of arachidonic acid from human lymphocytes by 51% at 10(-8) M. 2. Under normal culture conditions, nanomolar gravidin caused a significant reduction in the release of free arachidonic acid from human lymphocytes or nontransformed fibroblasts but in transformed cells, nanomolar gravidin was ineffective. 3. Inhibition of arachidonate release appeared to be related to rate of growth as inhibitory effects of gravidin on Jurkat cells and HL-29 cells could be observed if the cells were cultured under conditions where DNA synthesis was low. 4. The reported disparate effects of lipocortin on cell phospholipase A2 activity may be reconciled if DNA synthesis is investigated. 相似文献
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63.
Jos F M de Jonghe Kees J Kalisvaart Marty Dijkstra Huib van Dis Ralph Vreeswijk Martin G Kat Piet Eikelenboom Tjeerd van der Ploeg Willem A van Gool 《The American journal of geriatric psychiatry》2007,15(2):112-121
OBJECTIVES: The authors investigated prodromal delirium symptoms in elderly patients undergoing hip surgery. METHODS: This was a prospective cohort study in the setting of a large medical school-affiliated general hospital in Alkmaar, The Netherlands. Participants were patients undergoing hip surgery aged 70 and older at risk for delirium. Before surgery, patients were randomized to low-dose prophylactic haloperidol treatment or placebo. Daily assessments were based on patient interviews with the Mini-Mental State Examination and Digit Span test. The Delirium Rating Scale-Revised (DRS-R-98) was used to measure early symptoms during the prodromal phase before the onset of delirium. RESULTS: Data of 66 patients with delirium were compared with those of 35 at-risk patients who did not develop delirium: 14 of 66 patients (21%) had delirium on the day of surgery or early the day after, 32 of 66 (48%) on the second day, 14 of 66 on the third, and six of 66 (9%) on the fourth. The average DRS-R-98 total scores on day -4 to day -1 before delirium were 1.9 for the comparison group patients and 5.0, 4.3, 5.8, and 10.7 for patients with postoperative delirium. Multivariate analysis showed that the early symptoms memory impairments, incoherence, disorientation, and underlying somatic illness predict delirium. CONCLUSIONS: Most elderly patients undergoing hip surgery with postoperative delirium already have early symptoms in the prodromal phase of delirium. These findings are potentially useful for screening purposes and for optimizing prevention strategies targeted at reducing the incidence of postoperative delirium. 相似文献
64.
Jeremy L Emken Elspeth M Mcdougall Ralph V Clayman 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2004,8(2):195-199
Laparoscopic surgery is gaining popularity among the surgical community. While its prevalence expands, the need for reliable training and assessment tools is becoming increasingly important. Laparoscopic skills are not an innate behavior, nor can they be easily mimicked, and can only be acquired through hands-on training. A consensus exists among physicians that establishment and evaluation of technical skill in surgical training programs are inadequate and in need of improvement. A validated, reliable bench model that could train and assess could be standardized and provide numerous benefits including determination of which medical students should consider a career in surgery, valuable feedback to residents, a tracking mechanism of resident performance, a possible certification and recertification tool, and to allow for interinstitutional comparison. To this end, several potentially successful bench models testing dexterity, hand-eye coordination, and depth perception have been developed. A few models have been proven to be both valid and reliable indicators of technical skill. Although the future remains uncertain, enough groundwork has been laid to begin incorporating technical skill training and assessment into surgical training programs. 相似文献
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66.
Jeffrey A Morgan Ranjit John Yookyung Park Linda J Addonizio Mehmet C Oz Niloo M Edwards Jan M Quaegebeur Ralph S Mosca 《The Journal of heart and lung transplantation》2005,24(1):58-62
BACKGROUND: Many cardiac transplant programs have liberalized donor eligibility criteria in an attempt to maximize donor supply and to accommodate increasing demand. Although many studies have evaluated the potential adverse effects of prolonged donor ischemic time (DIT) in adults undergoing cardiac transplantation, relatively few have focused specifically on pediatric recipients that include a substantial number of patients and long-term follow-up. The focus of this study was to examine the effect of extended DIT on mortality after pediatric heart transplantation. METHODS: We conducted a retrospective review of our pediatric cardiac transplant experience in the past 11 years, comparing patients who received allografts and had ischemic times >240 minutes with those who had ischemic times <240 minutes. RESULTS: A total of 129 pediatric patients (<19 years) underwent orthotopic heart transplantation, of whom 78 (60.5%) had DIT <240 minutes and 51 (39.5%) had DIT >240 minutes. We found no statistically significant difference in age, sex, race, height, weight, or donor age between the groups (p = not significant). Post-transplant survival at 1, 5, and 10 years was similar for both groups: 91.2%, 88.0%, and 85.2%, respectively, for patients with DIT <240 minutes vs 89.6%, 87.2%, and 79.8%, respectively, for patients with DIT >240 minutes (p = 0.433). Additionally, using Cox proportional hazard models, extended DIT >240 minutes was not a statistically significant independent predictor of post-transplant mortality (odds ratio, 0.655; 95% confidence interval, 0.518-0.972; p = 0.684; standard error = 0.468). CONCLUSION: Procurement of hearts from distant locations with associated extended DIT is justified in the setting of increased demand and a fixed donor population. 相似文献
67.
Susanna L. Matsen Charles J. Yeo Ralph H. Hruban Michael A. Choti 《Journal of gastrointestinal surgery》2005,9(2):270-279
Humoral hypercalcemia of malignancy is widely associated with tumor production of parathyroid hormone related protein (PTH-rP).
This peptide functions in endocrine, autocrine and paracrine mechanisms in a manner similar to PTH; increasing renal uptake
of calcium, decreasing retention of phosphorous, and stimulating adenylate cyclase and phospholipase C. Although PTH-rP production
has been well documented in neoplasms of the exocrine pancreas, we present here two cases of endocrine pancreatic neoplasms
elaborating PTH-rP. We then review the literature of previous cases and delve into the pathophysiology of this peptide. 相似文献
68.
69.
Ralph Madeb Dragan Golijanin Joy Knopf Craig Nicholson Stuart Cramer Frederick Tonetti Kelly Piccone John R. Valvo Louis Eichel 《Journal of robotic surgery》2007,1(2):145-149
Several recent studies have suggested that thought leaders in radical prostatectomy have decreased their own positive margin
rates by switching from open to robot-assisted radical prostatectomy. Theoretically, this improvement is largely attributed
to enhanced visualization of the deep pelvis and precision of dissection afforded by the instrumentation. To date, it has
not been determined if this phenomenon exists amongst non-fellowship-trained urologists in private practice. Herein, we describe
the positive margin rates of two non-fellowship-trained private-practice urologists who converted from open radical retropubic
prostatectomy to robot-assisted radical prostatectomy. The margin positivity data from two non-fellowship-trained private-practice
urologists (surgeon 1 and surgeon 2) were reviewed retrospectively. The last 50 cases of open radical retropubic prostatectomy
from each surgeon were compared with the first 50 robotic prostatectomy cases of surgeons 1 and 2, respectively. A positive
surgical margin was defined as tumor present at the inked margin of the prostate. There was a significant decrease in the
overall and pT2 positive margin rates for both surgeons. The overall positive margin rate and pT2 positive margin rate for
surgeon 1 dropped from 44 to 20% and from 37 to 5.7%, respectively, after changing from open to robotic prostatectomy. For
surgeon 2, the overall positive margin rate changed from 26 to 18% and the pT2 positive margin rate changed from 27.5 to 7%
after converting. Changing from open to robotic-assisted radical prostatectomy may improve the ability of urologists to obtain
negative surgical margins. With proper training this phenomenon does seem to apply to non-fellowship-trained urologists in
private practice and can be realized within the first 50 cases performed. 相似文献
70.
Eva-Maria Brick Heike Rudolph Jens Arnold Ralph G Luthardt 《Computerized medical imaging and graphics》2004,28(3):159-165
The three-dimensional (3D) evaluation and comparison of free-form-surfaces is a complex problem [Dent. Mater. 8 (1992) 49; J. Dent. Res. 76 (1997) 1799; Dent. Mater. 16 (2000) 145; J. Prosthet. Dent. 70 (1993) 457; Dent. Mater. 19 (2003) 19]. However, it is essential in order to analyze the sinter shrinkage of dental ceramic-restorations where isotropic and linear shrinkage is desired for accurate fit on the prepared teeth. In this article, we examine the 3D sinter shrinkage in general and for nine copings from alumina in particular. Using various scaled CAD-models in an iteration scheme, each model was compared to the filtered point cloud of the coping, determining the surface-cloud difference. The magnitude of deviations from linear sinter shrinkage was investigated. Furthermore, a new fabrication process for ceramic-restorations is introduced. 相似文献