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991.
University and Community Hospital Medical Student Emergency Medicine Clerkship Experiences 总被引:2,自引:2,他引:0
Objective : To determine whether there is a significant difference between educational opportunities for fourth-year medical students rotating at a university hospital (UH) compared with several community hospitals (CHs) during a mandatory emergency medicine (EM) clerkship.
Methods : A self-reported clinical tool was completed in real time by each student rotating for 2 weeks at the UH and 2 weeks at 1 of 4 CHs (3 affiliated and 1 unaffiliated). Students are required to document the number of patients seen and the number of procedures performed on each of 20 six-hour shifts. They rated the EM attending clinical teaching by site using a 5-point scale at the end of the clerkship.
Results : Most (95%) of the 87 students in the 7 clerkship blocks of the 1996–97 academic year rotated at the UH and a CH. Most (71%) students rated both the UH and the CH for the quality of teaching by attendings. There was a significant difference in the mean number of patients evaluated/shift (2.2 ± 0.10 vs 2.8 ± 0.10, UH vs CH; p < 0.001) and the mean number of procedures performed/shift (0.36 ± 0.04 vs 0.56 ± 0.05, UH vs CH; p < 0.001). Attending clinical teaching scores were significantly higher (p = 0.03) at the CHs.
Conclusions : The educational opportunities for students in an EM clerkship to evaluate patients and perform procedures were significantly greater at the community hospitals. Inclusion of community hospital settings in a medical student EM clerkship may optimize the clinical experience. 相似文献
Methods : A self-reported clinical tool was completed in real time by each student rotating for 2 weeks at the UH and 2 weeks at 1 of 4 CHs (3 affiliated and 1 unaffiliated). Students are required to document the number of patients seen and the number of procedures performed on each of 20 six-hour shifts. They rated the EM attending clinical teaching by site using a 5-point scale at the end of the clerkship.
Results : Most (95%) of the 87 students in the 7 clerkship blocks of the 1996–97 academic year rotated at the UH and a CH. Most (71%) students rated both the UH and the CH for the quality of teaching by attendings. There was a significant difference in the mean number of patients evaluated/shift (2.2 ± 0.10 vs 2.8 ± 0.10, UH vs CH; p < 0.001) and the mean number of procedures performed/shift (0.36 ± 0.04 vs 0.56 ± 0.05, UH vs CH; p < 0.001). Attending clinical teaching scores were significantly higher (p = 0.03) at the CHs.
Conclusions : The educational opportunities for students in an EM clerkship to evaluate patients and perform procedures were significantly greater at the community hospitals. Inclusion of community hospital settings in a medical student EM clerkship may optimize the clinical experience. 相似文献
992.
Peter Griffiths BA RGN & Jenifer Wilson-Barnett BA MSc PhD RGN FRCN FKCL 《Journal of advanced nursing》1998,27(6):1184-1192
A literature search was conducted to identify 'nursing led in-patient units' where the nurse is the designated leader of the clinical team. The review concentrates on studies which have attempted to measure the impact of nursing-led in-patient units and reviews both the methodology and outcomes. Three major bodies of work were identified. Lydia Hall's evaluation of the Loeb Center for Nursing and Rehabilitation (USA) is reviewed in some detail. This work was the model for 'nursing beds' at the two Oxfordshire Nursing Development Units (UK) in the 1980s. Studies evaluating these centres are reviewed and reports of similar UK units discussed. A third body of work evaluates a nurse-managed critical care environment. Common features include a case mix based on nursing need with nurses having authority to admit and discharge patients. While results are generally favourable, with improved patient independence, fewer readmissions, lower mortality and cost savings reported in some or all of the studies, all studies reviewed demonstrate the difficulties of applying an experimental model to real life clinical services. Methodological limitations render firm conclusions difficult. Techniques adopted from studies in field settings, the so-called 'quasi-experiment', are advocated as a remedy, as is further study of the process of care in investigating this model of care delivery. 相似文献
993.
994.
Combination therapy of an orthotopic renal cell carcinoma model using intratumoral vector-mediated costimulation and systemic interleukin-2. 总被引:2,自引:0,他引:2
Chie Kudo-Saito Elizabeth K Wansley M Eilene Gruys Robert Wiltrout Jeffrey Schlom James W Hodge 《Clinical cancer research》2007,13(6):1936-1946
PURPOSE: Interleukin (IL)-2 therapy is currently used for therapy of renal cell carcinoma (RCC). However, it is only effective in approximately 10% to 15% of patients, showing a need for additional therapies. We have previously described a replication-defective fowlpox vector encoding three costimulatory molecules (B7-1, ICAM-1, and LFA-3), designated rF-TRICOM. Here, we show that intratumoral administration of rF-TRICOM in an orthotopic RCC model effectively enhances tumor immunogenicity and reduces tumor burden in mice and the combination of rF-TRICOM and IL-2 is more effective than either therapy alone. EXPERIMENTAL DESIGN: RCC cells were implanted under the capsule of the kidney, and mice were given rF-TRICOM intratumorally 14 days later. We compared the effect of rF-TRICOM, rF-granulocyte macrophage colony-stimulating factor (GM-CSF), and two doses of IL-2 and combinations of the above on antitumor efficacy and survival. Host CD4(+) and CD8(+) T-cell responses were also evaluated. RESULTS: The results show that (a) systemic IL-2 therapy was moderately effective in the reduction of tumor burden in an orthotopic RCC model; (b) a single intratumoral injection of rF-TRICOM and rF-GM-CSF significantly reduced tumor burden; (c) the addition of systemic IL-2 to intratumoral rF-TRICOM/rF-GM-CSF administration resulted in further reduction of tumor burden, decrease in the incidence of metastasis, and extended survival in tumor-bearing mice above that seen with either treatment alone; and (d) CD8(+) T cells played a critical role in the antitumor effect seen with rF-TRICOM/rF-GM-CSF + IL-2 therapy. Finally, the addition of systemic recombinant IL-15 or intratumoral vector-delivered IL-15 to intratumoral rF-TRICOM/rF-GM-CSF administration resulted in substantially more tumor-free mice than either therapy alone. CONCLUSIONS: These studies show that intratumoral administration of rF-TRICOM admixed with rF-GM-CSF is effective at reducing tumor burden in mice and the addition of IL-2 further contributes to this effect. These studies thus form the rationale for combination immunotherapy clinical trials in patients with RCC. 相似文献
995.
Autologous seeding of vascular grafts has been in use since 1972; however, the fate of seeded cells has never been determined. While short-term retention has been determined by radioactively labeling cells, long-term studies of seeded cells have not been possible due to the lack of an appropriate marker system. We have developed a long-term marker system for endothelial cells by transfecting the cells with bacterial genes that can be detected by fluorescentally-labeled antibodies to these markers. Two bacterial genes, neo and cat both carried by a pSV2 plasmid construct were used to co-transfect cells. Transfects were selected by growth in the presence of G418. Transfected clones were expanded into monolayers that stained positive for cat by fluorescence, and retained the normal cobblestone morphology and factor VIII staining of endothelial cells. By stably transfecting cells with bacterial genes these cells can now be used to seed vascular grafts and follow the long-term fate of seeded cells. 相似文献
996.
Angus M. McLean Elizabeth Babcock-Atkinson Kathleen Rein Donald A. Ruggirello Mario A. Gonzalez Patrick K. Noonan 《Pharmaceutical research》1987,4(4):327-331
Gallopamil is a calcium-channel antagonist with reported activity in experimental animals three to five times higher than that of verapamil. An automated high-performance liquid chromatographic (HPLC) method with fluorescence detection is described for the simultaneous determination of gallopamil and its metabolite norgallopamil in plasma. Gallopamil was well resolved from norgallopamil and other metabolites, allowing simultaneous quantitation of both drugs. The detection limit for both gallopamil and norgallopamil was 0.9 ng/ml. This method has been successfully used for the determination of gallopamil and norgallopamil following the administration of 25-, 37.5-, and 50-mg oral doses of drug. 相似文献
997.
John D Morris Elizabeth T Golub Shruti H Mehta Lisa P Jacobson Stephen J Gange 《AIDS research and therapy》2007,4(1):12-8
Background
Sustained use of antiretroviral therapy has been consistently shown to be one of the primary predictors of long-term effectiveness. Switching and discontinuation reflect patient and provider decisions that may limit future treatment options. In this study, we utilize data reported at semi-annual study visits from three prospective cohort studies, the AIDS Link to IntraVenous Exposure (ALIVE), the Women's Interagency HIV Study (WIHS), and the Multicenter AIDS Cohort Study (MACS), to investigate determinants of HAART modification with a particular focus on reported injection drug use (IDU). 相似文献998.
999.
Convergence of Genetic, Nutritional and Inflammatory Factors in Gastrointestinal Cancers 总被引:2,自引:0,他引:2
Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15–20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating an-giogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention. 相似文献
1000.
A. M. Diehl MD M. A. Chacon PhD J. J. Potter MS D Rolfes MD D. F. Cruess MD E Mezey MD 《Alcoholism, clinical and experimental research》1987,11(4):385-391
It has been suggested that pyridoxine deficiency may potentiate ethanol-induced liver injury. Our purpose was to clarify the effect of pyridoxine deficiency on ethanol-associated liver injury by comparing liver histology, serum liver enzymes, and the viability of cultured hepatocytes from pyridoxine-deficient and pyridoxine-sufficient rats that had been chronically fed ethanol-enriched diets. Our data fail to substantiate that pyridoxine-deficient animals are more susceptible to the hepatotoxic effects of ethanol than pair-fed pyridoxine-sufficient controls. Furthermore, the addition of pyridoxine to hepatocyte cultures fails to prevent in vitro cytotoxicity of added ethanol. Pyridoxine deficiency may augment ethanol-induced enhancement of hepatic urea synthesis. These data suggest that pyridoxine deficiency may contribute to the abnormal plasma amino acid profiles and nitrogen balance of chronic alcoholics, but that it does not potentiate ethanol-induced liver injury. 相似文献