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131.
Ventilation imaging of the lung: Comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy 总被引:1,自引:0,他引:1
Talissa A. Altes MD Patrice K. Rehm MD Frank Harrell PhD Michael Salerno PhD Thomas M. Daniel MD Eduard E. de Lange MD 《Academic radiology》2004,11(7):729-734
RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation. 相似文献
132.
Isabelle Durieu Evelyne Vericel Daniel Guichardant Hubert Roth Jean-Paul Steghens Jocelyne Drai Raphaele Nove Josserand Eric Fontaine Michel Lagarde Gabriel Bellon 《Journal of cystic fibrosis》2007,6(5):320-326
BACKGROUND: An imbalance in the ratio of arachidonic acid and docosahexaenoic acid (DHA) was found in cystic fibrosis (CF) affected tissues and was suggested to promote inflammation. Several studies have shown that the long chain n-3 fatty acids reduced inflammatory activity while others have highlighted prooxidant activity of DHA at high concentrations. The aim of our study was to evaluate the effects of an intravenous fish-oil emulsion enriched with n-3 FA in patients with CF on plasma and platelet FA composition and peroxidation markers. METHODS: 13 patients with CF received one IV emulsion per week of 2 mL/kg fish-oil n-3 emulsion for 12 weeks. RESULTS: There was a significant increase in 20:5 n-3 and 22:6 n-3 platelet FA composition, no variation in 20:4 n-6, a decrease in n-9. There was no variation in plasma FA composition. Specific urinary markers of lipid peroxidation derived from n-3 and n-6 showed a very high level before infusion compared with usual values in healthy subjects which was not affected by treatment. A significant weight loss and a decrease in reduced glutathione were observed in adult patients. CONCLUSIONS: The intravenous administration of n-3 FA in CF patients induced a significant modification in platelet FA composition but no modification of oxidative markers. However, the weight loss and the decreased level in reduced glutathione observed in adult patients may suggest a potential deleterious activity for some patients. Further studies are necessary to determine the optimal dose and route for long chain FA administration required to reach a potential beneficial effect. 相似文献
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135.
This study of interprofessional work relations in a Canadian mental health team examines how nursing deployed different forms of power in order to alter the mental health division of labour, to gain administrative, organizational and content control over its own work, expand its jurisdictional boundaries by expropriating the work of other professionals, and exclude others from encroaching on its old and newly acquired jurisdictions. This is set against the context of nursing's long-standing professional project to consolidate and expand its professional jurisdiction. Using an ethnographic study of a single interprofessional mental health team in a psychiatric hospital in Canada, the paper attempts to understand the politics and paradoxes involved in realizing nursing's professional project and how the politics of professional autonomy and professional dominance are actually conducted through micro-political struggles. The data demonstrates the effects of the political struggles at the organizational and work process levels, particularly in the forms of collaboration that result. Nurses gained substantial autonomy from medical domination and secured practical dominion over the work of non-medical professionals. New forms of interprofessional collaboration were accomplished through both simultaneous and sequential micro-political struggles with psychiatrists and non-medical professionals, and the formation of political alliances and informal agreements. Nursing solidarity at the elite level and substantial effort by the elite nurses and their committed colleagues to mobilize their less enthused members were fundamental to their success. The nurses deployed political (power) strategies and tactics to organize and reorganize themselves and other professionals on multiple levels (politically, organizationally, ideologically, socially and culturally). This study reveals the complexity and robustness of micro-political dynamics in the constitution of professional and collaborative interprofessional work relations. 相似文献
136.
Conclusion We would like to stress that we do not necessarily consider AC for SPECT MPI to be unfeasible or unworthy of scientific pursuit;
indeed, a great deal of creative scientific effort has been poured into this area of investigation over the past 3 decades,
and much of it has contributed to a better understanding of the physics, as well as the clinical aspects, of our field. However,
the great variety of available AC hardware and software “flavors,” the historical pattern of commercial release of insufficiently
validated AC implementations, and the increasingly clouded health care reimbursement horizon may have created an environment
where the envisioned users of the technology have been desensitized and discouraged from expecting it to ever come to fruition
in a standardized, validated, and costeffective form.
It has been reported as recently as 2005 that the “entire base of SPECT cameras has only 5% of systems with attenuation correction.”8
Perhaps the reports of AC’s demise are exaggerated, but it certainly seems as if the people have spoken and, after readying
themselves for the wolf one too many times, have come to the conclusion that “the future (of AC) ain’t what it used to be”
. . .at least not yet. 相似文献
137.
Minilaparoscopy-assisted natural orifice surgery. 总被引:5,自引:0,他引:5
Daniel A Tsin Liliana T Colombero Johann Lambeck Panagiotis Manolas 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(1):24-29
BACKGROUND AND OBJECTIVES: New technology has allowed us to perform major abdominal and pelvic surgeries with increasingly smaller instruments. The ultimate goal is surgery with no visible scars. Until current technical limitations are overcome, minilaparoscopy-assisted natural orifice surgery (MANOS) provides a solution. The aim of this study was to examine our clinical and experimental experience with MANOS. METHOD: Minilaparoscopic abdominal instruments were used together with a large vaginal port, which was used for insufflation, visual purposes, introduction of operative instruments, and specimen extraction. Minilaparoscopy-assisted intraperitoneal transgastric appendectomy was done in simulators (Lap trainer with SimuVision, Simulab Corp., Seattle, WA). RESULTS: Since 1998, we have used this technique in 100 cases including ovarian cystectomies, oophorectomies, salpingo-oophorectomies, myomectomies, appendectomies, and cholecystectomies. Some oophorectomies were performed after vaginal hysterectomy in cases where vaginal extraction was not possible. In this case series, we had only one complication, a case of postoperative fever after an ovarian cystectomy, which was diagnosed as drug-related fever. Our limited simulator experience showed that MANOS is a feasible technique for performing transgastric appendectomies. CONCLUSION: It may take several years for natural orifice surgery to become standard care. Meanwhile, MANOS could encourage and expedite this process. 相似文献
138.
139.
Nuray
. Kanbur Eudice Goldberg Leora Pinhas Robert M. Hamilton Robin Clegg Debra K. Katzman 《The International journal of eating disorders》2009,42(6):575-578
Anorexia nervosa (AN) can cause both functional and structural cardiac complications, including a variety of different conduction abnormalities. This is the first case report of symptomatic diurnal second‐degree atrioventricular (AV) block (Mobitz Type I) in an adolescent with AN. We present a 12‐year‐old girl with AN, restrictor sub‐type who reported cardiac symptoms during weight gain, at the time of the initial diagnosis of AV block. Second‐degree AV block (Mobitz Type I) is discussed as a possible complication of the AN, as well as being an intrinsic conduction system disease. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2009 相似文献
140.
Gastrojejunostomy stricture after Roux-en-Y gastric bypass occurs in 3 to 27% of morbidly obese patients in the USA. We questioned
whether preoperative patient characteristics, including demographic attributes and comorbid disease, might be significant
factors in the etiology of stricture. In this study from November 2001 to February 2006 (51 months), at a high-volume bariatric
center, of the 1,351 patients who underwent laparoscopic gastric bypass, 92 developed stricture (6.8%). All but two were treated
successfully by endoscopic dilation. All patients stopped nonsteroidal anti-inflammatory medications 2 weeks prior to surgery
and did not restart them. The operative procedure included the use of a 21-mm transoral circular stapler to create the gastrojejunostomy;
the Roux limb was brought retrogastric, retrocolic. In an effort to reduce our center’s stricture rate, late in the study,
U-clips used at the gastrojejunostomy were replaced by absorbable sutures, and postoperative H2 antagonists were added to the treatment protocol. The change to absorbable polyglactin suture proved to be significant, resulting
in a lower stricture rate. The addition of H2 antagonists showed no significant effect. Following the retrospective review of the prospective database, univariate and
multivariate logistic regression analyses identified factors associated with the development of stricture. Gastroesophageal
reflux disease and age were each shown to be statistically significant independent predictors of stricture following laparoscopic
gastric bypass.
Presented at the 2006 Annual Meeting of the Society for Surgery of the Alimentary Tract, May 20–24, Los Angeles, CA (poster
presentation). 相似文献