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991.
Developing case situations for ethics education in nursing   总被引:1,自引:0,他引:1  
Developing cases for the clinical teaching of ethics can be extremely time-consuming. Often, the cases that are developed either represent unrealistic situations or mere technical puzzles rather than genuine ethical problems. This article describes how faculty at the University of Minnesota modified a simple, quick and inexpensive think tank technique, the Crawford Slip Method, for use with nursing educators to generate an extensive list of ethical issues within each clinical specialty. Selecting from these lists, faculty in each specialty developed one realistic nursing case situation to illustrate selected ethical issues. Faculty were asked to use the Alverno College criteria for designing a moral dilemma when writing their cases. Suggestions for adapting the cases for multiple uses are presented.  相似文献   
992.
1. The metabolism of N,N-dimethyl-N'-(2-pyridyl)-N'-(2-thienylmethyl)-1,2- ethanediamine(methapyrilene, I) by liver microsomes from rat, guinea pig, and rabbit has been examined. 2. Methapyrilene-N-oxide, (III), normethapyrilene, (II), 2-thiophene methanol, (VI), 2-thiophene carboxylic acid, (VII), N-(2-pyridyl)-N',N'-dimethylethylenediamine, (IX), and methapyrilene amide, (XIV) were found in all species. 3. N-(2-Thienylmethyl)-2-amino pyridine, (VIII), 2-aminopyridine, (X), and (5-hydroxypridyl)-methapyrilene, (XII), were detected in rat and rabbit only. 4. N-Hydroxynormethapyrilene, (XXI), was tentatively identified by mass spectral fragmentation patterns only in rabbit liver microsomes incubations; however, it was found in 9000 g supernatant fraction incubations of rabbit, rat and guinea pig. 5. The formation of IX and XII was quantitatively more important in the rat than in either rabbit or guinea pig.  相似文献   
993.
994.
A diagnostic approach to assess liver metastases from colorectal carcinoma was prospectively evaluated in 30 patients with and without metastases on the basis of findings at conventional computed tomography (CT). With the technique, termed continuous CT angiography (CCTA), CT data were continuously sampled for 24 seconds at the same section level after initiation of a 3-second injection of 10-20 mL of contrast medium in the common hepatic artery. The procedure was repeated for each contiguous section level of the liver. Findings at preoperative ultrasound (US), conventional CT, and CCTA were compared with those at intraoperative US and surgical exploration as the standard of reference. Forty-four liver metastases were identified in 16 patients, and 14 patients had no metastases. CCTA had a sensitivity of 98% (43 lesions identified) and higher accuracy (81% [54 of 67 diagnoses]) than US and conventional CT. The data indicate that CCTA can supplement information obtained with conventional imaging techniques in patients who must undergo hepatic surgery because of metastases from colorectal carcinoma.  相似文献   
995.
996.
Induction of lyme arthritis in LSH hamsters.   总被引:24,自引:11,他引:13       下载免费PDF全文
In studies of experimental Lyme disease, a major obstacle has been the unavailability of a suitable animal model. We found that irradiated LSH/Ss Lak hamsters developed arthritis after injection of Borrelia burgdorferi in the hind paws. When nonirradiated hamsters were injected in the hind paws with B. burgdorferi, acute transient synovitis was present. A diffuse neutrophilic infiltrate involved the synovia and periarticular structures. The inflammation was associated with edema, hyperemia, and granulation tissue. Numerous spirochetes were seen in the synovial and subsynovial tissues. The histopathologic changes were enhanced in irradiated hamsters. The onset and duration of the induced swelling were dependent on the dose of radiation and the inoculum of spirochetes. Inoculation of irradiated hamsters with Formalin-killed spirochetes or medium in which B. burgdorferi had grown for 7 days failed to induce swelling. This animal model should prove useful for studies of the immune response to B. burgdorferi and the pathogenesis of Lyme arthritis.  相似文献   
997.
Summary: Purpose: Reducing the extracellular magnesium or calcium or increasing the extracellular potassium induces different patterns of epileptiform activity in the hippocampus and the entorhinal cortex. Although in the low Ca2+ and K+ models, seizure-like events (SLEs) develop in area CA1 of the hippocampus, only short recurrent discharges develop in the low Mg2+ model. In contrast, in low Mg2+, SLEs and late recurrent discharges (LRDs) are observed in the entorhinal cortex. Methods: We compared the effects of valproate (VPA) and its major metabolite, trans-2-en-VPA (TVPA), on all these different model activities using extracellular field potential measurements. We also investigated the equilibration time course of VPA in the slice by using VPA-sensitive microelectrodes. Results: Both drugs reversibly blocked most forms of epileptiform activity. The only exception was the LRDs in the entorhinal cortex. In paired experiments, TVPA appeared to be more effective than VPA bath applied with the same concentration to the same slice. With our measurements of the VPA concentrations in slices, we showed that the concentrations used were close to therapeutic drug levels. Conclusions: If TVPA stands the toxicological tests, it might be a useful alternative in the treatment of seizures.  相似文献   
998.
We studied the brace effect on the spinal profile in idiopathic scoliosis, using a MR procedure visualising the complete scoliotic spine in any vertical plane, while rotating it 180° on the longitudinal axis of the patient. Thirty-eight female patients (mean age, 14.5 years) were included in the study. Inclusion criteria were an idiopathic scoliosis, a Cobb angle greater than 20°, age of 10–17 years and bracing with a Chêneau brace. The brace effect was studied in 38 thoracic curves. The MR examinations were carried out in direct sequences, with and without brace. A reconstruction algorithm allows visualising the whole spine in vertical projections, with rotational steps of 2°, from –90° to 90°, referred to as MR animation. In various vertical MR projections, the changes of the curves were evaluated by measuring the Cobb angle. Additionally, a translation angle of the apical vertebra was determined, representing the lateral deviation of the apical vertebra from a defined midline. Testing the reproducibility of the Cobb angles, the standard deviation of the intra-individual differences was 1.7° and of the inter-individual differences, 2.1°. For the translation angles, the standard deviation of the intra-individual differences was 0.8° and of the inter-individual differences, 0.9°. With brace the mean Cobb angle of the thoracic curves was significantly reduced in the various vertical MR projections. The mean translation angle was also reduced. MR analysis showed that the brace effect is a translation process, straightening the profile of the scoliotic spine in all vertical planes. MR animation allows visualising the brace effect on the spine in scoliosis based on a 3D data set, without additional radiation exposure. It showed the straightening effect of the brace leading to a flattening of the sagittal spinal profile.  相似文献   
999.
1000.
Summary Monoclonal antibodies with differing specificity were prepared against the Josiah strain of the Lassa virus. All monoclonal antibodies were characterized by subclass determination and the immunofluorescence test against Lassa, LCM (WE & Arm strain), Junin, Machupo, and other arenavirus antigens. In radioimmune precipitation tests using purified Lassa virus antigen all monoclonal antibodies precipitated a single band of 60 kd, specific for the viral nucleoprotein (p 60). Three domains (A, B, C) were identified on the surface of the Lassa virus nucleoprotein using an ELISA-inhibition test. All domains carried different Lassa virus specific epitopes. In addition, the A-domain carried a group specific epitope present within the arenavirus family as a whole as shown by cross-reaction in immunofluorescence tests. The B-domain only carries Lassa virus specific epitopes, whereas the C-domain has a type specific and a subgroup specific (Lassa, LCM) epitope.  相似文献   
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