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121.
Charles W. Mayo Morris Fishbein Sylvia Covet Russell L. Cecil 《Postgraduate medicine》2013,125(4):378-392
Some important but little-emphasized nutritional aspects of gastrointestinal physiology are discussed. Experimental studies which form the basis for present understanding of fluid and electrolyte problems are reviewed briefly. Other topics include harmful and beneficial effects of gastrointestinal bacteria, protein-losing enteropathies, and nutritional problems associated with gastrointestinal resection. 相似文献
122.
Michael Chorny Ilia Fishbein Benjamin B. Yellen Ivan S. Alferiev Marina Bakay Srinivas Ganta Richard Adamo Mansoor Amiji Gary Friedman Robert J. Levy 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(18):8346-8351
The use of stents for vascular disease has resulted in a paradigm shift with significant improvement in therapeutic outcomes. Polymer-coated drug-eluting stents (DES) have also significantly reduced the incidence of reobstruction post stenting, a disorder termed in-stent restenosis. However, the current DESs lack the capacity for adjustment of the drug dose and release kinetics to the disease status of the treated vessel. We hypothesized that these limitations can be addressed by a strategy combining magnetic targeting via a uniform field-induced magnetization effect and a biocompatible magnetic nanoparticle (MNP) formulation designed for efficient entrapment and delivery of paclitaxel (PTX). Magnetic treatment of cultured arterial smooth muscle cells with PTX-loaded MNPs caused significant cell growth inhibition, which was not observed under nonmagnetic conditions. In agreement with the results of mathematical modeling, significantly higher localization rates of locally delivered MNPs to stented arteries were achieved with uniform-field–controlled targeting compared to nonmagnetic controls in the rat carotid stenting model. The arterial tissue levels of stent-targeted MNPs remained 4- to 10-fold higher in magnetically treated animals vs. control over 5 days post delivery. The enhanced retention of MNPs at target sites due to the uniform field-induced magnetization effect resulted in a significant inhibition of in-stent restenosis with a relatively low dose of MNP-encapsulated PTX (7.5 μg PTX/stent). Thus, this study demonstrates the feasibility of site-specific drug delivery to implanted magnetizable stents by uniform field-controlled targeting of MNPs with efficacy for in-stent restenosis. 相似文献
123.
William Cassidy Dale M. Marioneaux Aubrey F. Windham Susan Manning Daniel Fishbein Ronald L. Horswell 《The American journal of emergency medicine》2009
Factors correlating with successful administration of flu vaccine in an emergency department (ED) were examined. Patients 18 years and older were screened for indications for flu immunization. Vaccine was offered to those with indications. Of 3425 patients screened, 1311 had indications, 705 of 1311 agreed to immunization, and 513 of 705 were immunized. Factors related to immunization agreement were comorbidity, interviewer, and being 50 to 64 years old with prior immunization. Immunization factors were month, comorbidity, and not being pregnant. Factors associated with suboptimal acceptance and receipt should be addressed in future efforts. 相似文献
124.
Amber L. Hartman Denver M. Lough Dinesh K. Barupal Oliver Fiehn Thomas Fishbein Michael Zasloff Jonathan A. Eisen 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(40):17187-17192
Small bowel transplants provide an exceptional opportunity for long-term study of the microbial ecology of the human small bowel. The ileostomy created at time of transplant for ongoing monitoring of the allograft provides access to samples of ileal effluent and mucosal biopsies. In this study, we used qPCR to assay the bacterial population of the small bowel lumen of 17 small bowel transplant patients over time. Surprisingly, the posttransplant microbial community was found to be dominated by Lactobacilli and Enterobacteria, both typically facultative anaerobes. This represents an inversion of the normal community that is dominated instead by the strictly anaerobic Bacteroides and Clostridia. We found this inverted community also in patients with ileostomies who did not receive a transplant, suggesting that the ileostomy itself is the primary ecological determinant shaping the microbiota. After surgical closure of the ileostomy, the community reverted to the normal structure. Therefore, we hypothesized that the ileostomy allows oxygen into the otherwise anaerobic distal ileum, thus driving the transition from one microbial community structure to another. Supporting this hypothesis, metabolomic profiling of both communities demonstrated an enrichment for metabolites associated with aerobic respiration in samples from patients with open ileostomies. Viewed from an ecological perspective, the two communities constitute alternative stable states of the human ileum. That the small bowel appears to function normally despite these dramatic shifts suggests that its ecological resilience is greater than previously realized. 相似文献
125.
Paul R. SierzenskiJoel M. Schofer MD LCDR MC USN Michael J. BaumanJason T. Nomura MD RDMS 《The Journal of emergency medicine》2011
Background: Emergency physicians commonly perform Focused Assessment with Sonography for Trauma (FAST) examinations to evaluate for free intraperitoneal fluid. Many ultrasound findings can be misinterpreted as free fluid, resulting in false-positive FAST examinations. Objectives: To describe a previously unreported ultrasound finding that can be misinterpreted as free intraperitoneal fluid. Case Report: A 32-year-old man was stabbed in the left upper abdomen. A FAST examination was performed and a right perinephric fat pad was interpreted as showing free fluid in Morison's pouch. After transfer to a trauma center, a repeat FAST examination revealed no signs of intraperitoneal free fluid. Wound exploration showed no signs of penetration into the peritoneal cavity. Conclusions: When performing a FAST examination, a wedge-shaped hypoechoic area in Morison's pouch that is bounded on both sides by echogenic lines (the “FAST Double-Line Sign”) is likely to represent perinephric fat and may result in a false-positive FAST examination. 相似文献
126.
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128.
MC Chau SF Leung KM Kam KY Cheung WH Kwan KH Yu KW Chiu TC Chan 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):480-484
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process. 相似文献
129.
Summers W. Taylor CPT MC U.S.A. Danny R. Barnhill LTC MC U.S.A. Thomas W. Burke MAJ MC U.S.A. W.Kenneth Linville CPT MC U.S.A. Irene Yevich MAJ MC U.S.A. 《Gynecologic oncology》1989,33(3):376-378
The folic acid antagonist, methotrexate, has many applications in the treatment of neoplastic disease. While methotrexate produces several well-recognized toxic effects, cutaneous reactions are rare. A patient who developed classical erythema multiforme while receiving low-dose methotrexate as treatment of nonmetastatic gestational trophoblastic neoplasia is presented. Erythema multiforme has been associated with a variety of pharmacologic agents. It typically presents as a pruritic papular dermatitis of the extensor surfaces of the extremities and may require multiple skin biopsies to establish the diagnosis. Spontaneous reversal usually occurs with discontinuation of therapy. Patients developing erythema multiforme related to antineoplastic agents should be switched to an alternate regimen. 相似文献
130.
F Hatton MH Bouvier-Colle A Barois MC Imbert A Leroyer S Bouvier E Jougla 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(12):1366-1371
An enquiry into sudden infant death syndrome (SIDS) in 1987 furnished us with detailed epidemiological data for 281 cases that underwent a thorough post-mortem examination. This analysis uses these data to evaluate the role the autopsy plays in explaining sudden death. The cases were classified into three diagnostic groups: explained causes of death (group 1), unexplained deaths with anomalies (group 2), and no anomaly (group 3). These 281 cases show the three essential features that characterize SIDS: over-representation of males, increased deaths during the second and third months of life, and increased deaths during winter. The autopsy examination revealed that many of these deaths had a medical explanation. Almost half were assigned to group 1. At the time of autopsy, no precise pathology could be diagnosed for 147 deaths; of these, 140 showed histological anomalies. There were only seven sudden deaths for which no abnormal sign was evident at the autopsy. These results are compared with those of similar studies and discussed in connection with three factors: the initial selection of cases, the nature and degree of the investigations, and the possible interpretations of the symptoms uncovered. 相似文献