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81.
Daoyan Wei Henry Q. Xiong James L. Abbruzzese Keping Xie 《Journal of gastrointestinal cancer》2003,33(1):43-60
Pancreatic cancer is a lethal disease characterized by early metastasis, local invasion, and resistance to conventional therapies. To understand its etiology and eventually make prevention of it possible and effective, appropriate carcinogenesis models will certainly help us understand the effects of environmental and genetic elements on pancreatic carcinogenesis. The development of new treatment strategies to control cancer metastasis is of immediate urgency. Fulfillment of this task relies on our knowledge of the cellular and molecular biology of pancreatic cancer metastasis and the availability of biologically and clinically relevant model systems. Many of the existing pancreatic cancer carcinogenesis and metastasis animal models are described in this review. The advantages and disadvantages of each model and their clinical implications are discussed, and special attention is focused on experimental therapeutic strategies targeting pancreatic cancer metastasis. 相似文献
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Turboprop: improved PROPELLER imaging. 总被引:1,自引:0,他引:1
A variant of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI, called turboprop, is introduced. This method employs an oscillating readout gradient during each spin echo of the echo train to collect more lines of data per echo train, which reduces the minimum scan time, motion-related artifact, and specific absorption rate (SAR) while increasing sampling efficiency. It can be applied to conventional fast spin-echo (FSE) imaging; however, this article emphasizes its application in diffusion-weighted imaging (DWI). The method is described and compared with conventional PROPELLER imaging, and clinical images collected with this PROPELLER variant are shown. 相似文献
85.
Mary Ann Richardson Helen M Chao Laura L Read James D Clelland Raymond F Suckow 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(2):195-197
Phenylketonuria (PKU), an inborn error of phenylalanine metabolism, has been shown to be a risk factor for tardive dyskinesia (TD). In male psychiatric patients there was a significant relationship between TD and measures of plasma phenylalanine following ingestion of a standardized phenylalanine dose that was indicative of higher brain availability of phenylalanine in patients with TD. In addition, a medical food formulation consisting of branched chain amino acids, which compete with phenylalanine for transport across the blood-brain barrier, has been demonstrated to be an efficacious treatment for TD. Cumulatively these findings suggested that TD was related to phenylalanine metabolism and thus that sequence variants in the gene for phenylalanine hydroxylase (PAH), the rate-limiting enzyme in the catabolism of phenylalanine, could be associated with TD susceptibility. Genetic screening of PAH in a group of 123 psychiatric patients revealed ten sequence polymorphisms and two mutations, but none appeared to be a significant risk factor for TD. 相似文献
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Christine E. East Fung Yee Chan Shaun P. Brennecke James F. King Paul B. Colditz 《分娩》2006,33(2):101-109
Abstract: Background: Fetal pulse oximetry improves the assessment of fetal well‐being during labor. The objective of this study was to evaluate women's satisfaction with their experience with this additional technology. Methods: We surveyed women participating in the FOREMOST trial, a randomized controlled trial comparing the addition of fetal pulse oximetry (FPO) to conventional cardiotocograph (CTG) monitoring (intervention group), versus CTG‐only (control group), in the presence of nonreassuring fetal status during labor. Our survey evaluated 3 aspects of women's experience: labor, fetal monitoring, and participation in the research. The survey was administered within a few days of giving birth and repeated 3 months later. Results: No differences were found between the intervention and control groups for women's evaluations of their labor, fetal monitoring, research, or overall experiences when surveyed on both occasions. Within each study group, a small but statistically significant decline occurred in women's scores for their experience of labor and overall experience from the initial survey close to the time of giving birth, to 3 months later. The magnitude of differences in responses over time was similar for the both groups. Women were more satisfied after a spontaneous or assisted vaginal birth than after cesarean section. Length of time the research midwife was present had a significant positive effect on women's ratings of their experience several days after giving birth (p = 0.006), but no effect at 3 months. Conclusions: The addition of fetal pulse oximetry for the assessment of fetal well‐being during labor did not affect childbearing women's perceptions of fetal monitoring or their labor. Women evaluated their experience in the research process positively overall. Small changes occurred in women's perception of their satisfaction over time. (BIRTH 33:2 June 2006) 相似文献
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Mohammad K. Jamal M.D. Eric J. DeMaria M.D. Jason M. Johnson D.O. Brennan J. Carmody M.D. Luke G. Wolfe M.S. John M. Kellum M.D. Jill G. Meador R.N. 《Surgery for obesity and related diseases》2006,2(2):417-127
BACKGROUND: Preoperative dietary counseling (PDC) before bariatric surgery is mandated by a growing number of insurance payers. Their claim is that PDC improves outcomes and postoperative compliance. We compared outcomes of GBP patients undergoing a mandatory 13 weeks of PDC (n = 72) to a contemporaneous group of patients with no such requirement (no-PDC; n = 252) who underwent operation between January 2000 and December 2002. METHODS: The PDC and no-PDC groups were characterized by similar male:female ratios (1:4 vs 1:4.6), mean age (42 years), mean body weight (324 lb vs 309 lb), and mean body mass index (BMI) (52 kg/m2 vs 50 kg/m2). The PDC group had a higher incidence of obstructive sleep apnea compared with the no-PDC group (41% vs 28%; P < .04) but otherwise the two groups had similar incidences of obesity-related comorbidities. The presurgery dropout rate was 50% higher in the PDC group than in the no-PDC group (28% vs 19%; P < .05). RESULTS: At 1 year follow-up, the no-PDC patients had a statistically greater percentage excess weight loss (67% vs 60%; P < .0001), lower BMI (32 vs 35; P < .015), and lower body weight (197 vs 218; P < .01). Resolution of major comorbidities, complication rates, 30-day postoperative mortality, and postoperative compliance with follow-up were similar in the two groups. CONCLUSIONS: The data demonstrate that insurance-mandated PDC is an obstacle to patient access for surgical treatment of severe obesity and has no impact on weight loss outcome or postsurgical compliance. PDC should be abandoned by the insurance industry. 相似文献
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