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Laura I Sacolick Douglas L Rothman Robin A de Graaf 《Magnetic resonance in medicine》2007,57(3):548-553
Because of their excellent slice profiles and high immunity to RF inhomogeneity, adiabatic full passage (AFP) pulses are ideal for use in spatial localization. The nonlinear, position-dependent phase of a single AFP pulse generated during refocusing of transverse magnetization traditionally is eliminated by using identical pairs of AFP pulses, at the expense of increased RF power deposition and increased echo time (TE). Here it is shown that one can achieve significant phase refocusing by executing single AFP pulses along non-equivalent spatial axes. When used for volume selection in MR spectroscopic imaging (MRSI) the remaining nonlinear phase becomes inconsequential when the phase across a spectroscopic volume is small. Selection of rectangular and octagonal volumes is demonstrated with half the number of AFP pulses used in the traditional approach. It is shown that octagonal volume selection in the human brain provides excellent suppression of extracranial lipids, and thus allows multislice (1)H MRSI at 4 Tesla to be performed within the guidelines for RF power deposition. 相似文献
64.
John C Siegle Laura J Bishop William F Rayburn 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(1):30-34
OBJECTIVE: We compared 2 techniques for performing a partial salpingectomy by using microlaparoscopy and either bipolar coagulation or loop ligation. METHODS: A 3-mm transumbilical laparoscope with secondary midline port sites midway and suprapubically was used to perform a partial salpingectomy in 109 women desiring permanent sterilization. Each patient was randomly assigned to undergo a tubal resection either after Pomeroy ligation (n= 54) or after bipolar coagulation with Kleppinger forceps (n=55). Postoperative pain, as assessed using a 10-point visual analog scale, was the primary comparison endpoint. RESULTS: No technical difficulties with either technique required conversion to a minilaparotomy. The mean time to remove both tubal segments was not different between techniques (7 minutes, 21 seconds; range, 4 minutes, 25 seconds to 15 minutes, 43 seconds). Each segment (mean, 1.6 cm; range, 0.8 to 3.5 cm) was confirmed in the operating room, then histologically. Postoperative pain at 6 hours was scored similarly (median, ligation 4.6, coagulation 4.0 of 10). Outpatient recovery was the same, unless pelvic pain required overnight observation (ligation, 4 patients; coagulation, 2 patients). CONCLUSION: Partial salpingectomy, using microlaparoscopy with either bipolar coagulation or loop ligation, was performed with comparable ease, confirmation of the removed tube, and similar postoperative discomfort. 相似文献
65.
Paolo De Simone Paola Carrai Lidiana Baldoni Stefania Petruccelli Laura Coletti Luca Morelli Franco Filipponi 《Liver transplantation》2005,11(9):1080-1085
We report the results of a retrospective review of the outpatient pretransplantation workup for United Network for Organ Sharing (UNOS) 3 patients adopted at a liver transplantation (LT) center and illustrate the efficiency indicators used for quality evaluation and cost-analysis. A single-center, pre-LT evaluation workup was performed on an outpatient basis at a cost per patient evaluation of 2,770 Euros (). Objective measures were: the number of patients admitted to and excluded from each phase of the algorithm; the rate of patients admitted to pre-LT evaluation out of the total of referred patients (the referral efficiency rate); the rate of waitlisted patients out of those admitted to pre-LT evaluation (the evaluation efficiency rate); the rate of waitlisted patients out of those referred for LT (the process efficiency rate); and the cost per waitlisted patient, as the ratio of the cost per patient evaluation to the evaluation efficiency rate. From January 1, 1996, to October 1, 2004, 1,837 patients were referred for LT on an outpatient basis. Based on preemptive evaluation of the available clinical data, 412 patients (22.4%) were excluded from pre-LT evaluation and 1,425 (77.6%) were admitted to preliminary consultation. Among these, 603 (42.3%) were excluded from and 822 (57.7%) were admitted to pre-LT evaluation with a referral efficiency rate of 44.7% (822 of 1,837). Out of the patients evaluated for LT, 484 were waitlisted with a cost-utility and evaluation efficiency rate of 58.8% each (484 of 822). Of the 1,837 patients originally addressed for LT 484 were waitlisted, yielding a process efficiency rate of 26.3% (484 of 1,837) and a cost per waitlisted patient of 4,710.8. In conclusion, the 3 indicators allowed monitoring of the efficiency of the pre-LT evaluation algorithm. The current process efficiency rate at our center is low (26.3%), but avoiding early referrals we might increase it to 31.6%, with a 12% net saving on costs per waitlisted patient (from 4,710.8 to 4,165.4). 相似文献
66.
The aim of this study was to evaluate corneal innervation in soft contact lens wearers using the Tomey Confoscan confocal microscope (40x/0.75 objective lens). Three distinct age- and sex-matched subject groups were involved, including extended soft (hydrogel and silicone-hydrogel) contact lens wearers, overnight soft (hydrogel) contact lens wearers, and non contact lens wearers. A number of variables were objectively measured, subjectively evaluated, or graded in order to investigate the distribution and morphology of corneal nerves. For most of the evaluated parameters, no statistically significant differences were found. However, qualitative observations showed noticeable differences in corneal nerve appearance among the different subject groups; the degree of corneal oedema was suggested as the main causative factor. In conclusion, neither the short-term (overnight wear) nor the long-term (12-month extended wear) soft contact lens wear appeared to affect the morphology and/or distribution of corneal nerves as viewed with confocal microscopy. 相似文献
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Anna Gliszczyńska-Swig?o Hester van der Woude Laura de Haan Bozena Tyrakowska Jac M M J G Aarts Ivonne M C M Rietjens 《Toxicology in vitro》2003,17(4):423-431
The effects of quercetin on viability and proliferation of Chinese Hamster Ovary (CHO) cells and CHO cells overexpressing human quinone reductase (CHO+NQO1) were studied to investigate the involvement of the pro-oxidant quinone chemistry of quercetin. The toxicity of menadione was significantly reduced in CHO+NQO1 cells compared to wild-type CHO cells, validating the NQO1-overexpression in the CHO+NQO1 transfectant. Quercetin inhibited the proliferation of wild-type CHO and CHO+NQO1 cells to a similar extent without affecting cell viability, indicating that NQO1 enrichment of CHO cells did not provide increased protection. On the other hand, inhibition of NQO1 in both types of cells by dicoumarol significantly potentiated the inhibitory effect of quercetin on cell proliferation, revealing the role of NQO1 in cellular protection against quercetin. Altogether, these results can be explained by the hypothesis that both wild-type CHO and CHO+NQO1 cells contain sufficient NQO1 activity for optimal protection against the pro-oxidant effect of quercetin on cell proliferation. The results also point at a cellular NQO1 threshold for optimal protection against quercetin. This NQO1 threshold seems to be in the range of NQO1 activities already present in various tissues. 相似文献
70.
Bonnie L. Westra R.N. Ph.D. Laura Cullen R.N. M.A. Donna Brody R.N. M.S.N. Patricia Jump R.N. M.S. Letitia Geanon R.N. M.S. Ellen Milad R.N. M.S. 《Public health nursing (Boston, Mass.)》1995,12(6):393-399
Abstract Client (patient) satisfaction has been studied extensively in the health care sector, yet those receiving home health care services have been the focus of few studies. The purpose of this study was to test the reliability and validity of the Home Care Client Satisfaction Instrument (HCCSI). A total of 400 clients, randomly selected from 20 randomly chosen home care agencies in one state, completed the HCCSI and demographic form. Most respondents were older adults with multiple health problems and their families or informal support systems. Since data were skewed, item analysis was used. The revised instrument (HCCSI-R) is unidimensional and includes 12 items rated on a 5-point Likert scale measuring specific aspects of care. In addition, there are three global measures of satisfaction rated on a 10-point scale. All items except one had significant item-total correlations greater than .59. The total score correlates with likeliness to recommend the agency to others (.37, p = .0001), showing some evidence for criterion-related validity. 相似文献