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21.
A single scan technique for estimating acid output.   总被引:2,自引:0,他引:2  
A single scan technique using 99mTc has been developed for the measurement of gastric acid output. After an overnight fast, pentagastrin (6 microgram/kg S.C.) was given 15 min before 99mTc (1 mCi i.v.), and a scan of the abdomen was performed 15 min later using a double-headed scanner. Accumulation of isotope within the stomach was then calculated from the scan and expressed as a percentage of the injected dose. Pentagastrin-stimulated intragastric activity correlated with acid output measured conventionally on a separate occasion (r = 0.87, P less than 0.0001). The test is rapidly performed with minimal inconvenience and discomfort to the patient, and the dose of irradiation used is small. The advantages of the method compared with intubation and gastric aspiration are discussed.  相似文献   
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Glioblastoma muhiforme (GBM) is a highly invasive brain tumour that is unvaryingly fatal in humans clesplte even aggres- sive therapeutic approaches such as surgical resection followed by chemotherapy and radiotherapy. Unconventional treatment options such as gene therapy provide an intriguing option for curbing glioma related deaths. To date, gene therapy has yielded encouraging results in preclinical animal models as well as promising safety profiles in phase I clinical trials, but has failed to demonstrate significant therapeutic efficacy in phase III clinical trials. The most widely studied antiglioma gene therapy strategies are suicide gene therapy, genetic immuno- therapy and oncolytic virotherapy, and we have attributed the challenging transition of these modalities into the clinic to four major road- blocks : ( 1 ) anatomical features of the central nervous system, (2) the host immune system, (3) heterogeneity and invasiveness of GBM and (4) limitations in current GBM animal models. In this review, we discuss possible ways to jump these hurdles and develop new gene therapies that may be used alone or in synergy with other modalities to provide a powerful treatment option for patients with GBM.  相似文献   
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Renal transplantation in recipients with an ileal conduit is uncommon and occasionally controversial as it has been associated with high morbidity and mortality rates. We report on 17 patients with an ileal conduit who received a deceased donor renal transplant at our institution between January 1986 and December 2012. We retrospectively reviewed their allograft and surgical outcome. There were four mortalities at five, five, 39, and 66 months post‐transplant. Sixteen of 17 grafts functioned immediately; one patient had primary non‐function secondary to vascular thrombosis. Thirteen of 17 (76.5%) grafts were functioning at a mean follow‐up period of 105 months. The mean serum creatinine at follow‐up was 111 μM (±38.62). Five patients had seven episodes of urosepsis requiring hospital admission, and five patients received treatment for renal stone disease. We conclude that given improvements in immunosuppression, surgical technique, infection treatment, and selection criteria, we believe that renal transplantation in the patient with an ileal conduit yields excellent graft survival, although there is a high morbidity rate in this cohort of patients in the long term.  相似文献   
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The recent growth in online technology has led to a rapid increase in the sharing of health related information globally. Health and social care professionals are now using a wide range of virtual communities of practice (VCoPs) for learning, support, continuing professional education, knowledge management and information sharing. In this article, we report the findings from a review of the literature that explored the use of VCoPs by health and social care professionals to determine their potential for interprofessional education and collaboration. We employed integrated review methods to search and identify relevant VCoP articles. We undertook searches of PubMed and Google Scholar from 2000, which after screening, resulted in the inclusion of 19 articles. A thematic analysis generated the following key issues related to the use of VCoPs: ‘definitions and approaches’, ‘technological infrastructure’, ‘reported benefits’, ‘participation issues’, ‘trust and privacy and ‘technical ability’. Based on the findings from this review, there is some evidence that VCoPs can offer an informal method of professional and interprofessional development for clinicians, and can decrease social and professional isolation. However, for VCoPs to be successful, issues of privacy, trust, encouragement and technology need to be addressed.  相似文献   
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Inflammation in the lung can lead to increased expression of inducible nitric oxide synthase (iNOS) and enhanced NO production. It has been postulated that the resultant highly reactive NO metabolites may have an important role in host defence, although they might also contribute to tissue damage. However, in a number of inflammatory lung diseases, including bronchiectasis, iNOS expression is increased but no elevation of airway NO can be detected. A potential explanation for this finding is that NO is rapidly scavenged by reaction with superoxide radicals, forming peroxynitrite, which is preferentially metabolized via nitration and nitrosation reactions. To test this hypothesis, anaesthetized, specific pathogen-free rats were inoculated with Pseudomonas aeruginosa incorporated into agar beads (chronically infected group) or sterile agar beads (control group). Ten to 15 days later, the lungs were isolated and fixed. Pseudomonas organisms were isolated from the lungs of the chronically infected group. These lungs showed extensive inflammatory cell infiltration and tissue damage, which were not observed in control lungs. Expression of iNOS was increased in the chronically infected group when compared with the control group. However, the mean number of cells staining for nitrotyrosine in the chronically infected group was not significantly different from that in the controls, nor was there an excess of nitrotyrosine, nitrate, nitrite or nitrosothiol concentrations in the infected lungs. Thus, no evidence was found of increased NO metabolites in chronically infected lungs, including products of the peroxynitrite pathway. These findings suggest that chronic infection does not cause increased iNOS activity in the lung, despite increased expression of iNOS.  相似文献   
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