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91.
Despite the increased attention that problem-based learning has received as an appropriate pedagogical technique for educating adults for professional practice, reports that evaluate the process are rare and usually relate to professions other than nursing. A study was undertaken in order to discover the graduates' own perceptions of a problem-based learning programme and its effectiveness in preparing them for the reality of their chosen profession. Twelve practising graduate nurses who had completed the programme were interviewed according to the ethnographic method. Three categories were identified from the data: 'and all of a sudden...', which describes the transition from PBL student to staff nurse; 'not an unthinking assistant', where the characteristics that the PBL graduates believe make them different from traditionally trained nurses are described; and 'the buck stops here', which describes the sense of personal responsibility that the graduates experience in terms of their learning and actions.  相似文献   
92.
Considerable basic research, mostly in the past 20 years, has elicited greatly increased knowledge concerning the structure and function of cell adhesion molecules. Scores of individual adhesion molecules have been identified and categorized as to major structural features, ligands recognized, and pattern of expression. Recent attention has been focused on the interaction of cell adhesion molecules with intracellular components, and the role of cell adhesion molecules in mediating cell signal transduction. Ongoing efforts to develop specific pharmacological agonists and antagonists for adhesion molecules holds great promise in clinical medicine. Abciximab (Reopro), a monoclonal antibody inhibitor of the platelet integrin alpha IIb beta 3, is currently approved and available to improve vessel patency in patients undergoing angioplasty. Similar approaches to develop adhesion-based therapies to block angiogenesis, tumor progression, and/or metastasis are under development and hold promise for patients with cancer.  相似文献   
93.
Non-steroidal anti-inflammatory drugs inhibit constitutive (COX-1) and induced cyclooxygenase (COX-2), blocking prostaglandin production. We have compared the effects on nociceptive reflexes of meloxicam, which is COX-2 selective, with indomethacin, which is non-selective, using an in vitro spinal cord preparation. Cords were taken from naive rats, and from rats with carrageenan-induced hyperalgesia of one hindpaw. Reflex thresholds were lower in carrageenan preparations. Superfusion with meloxicam (10-100 microM) dose-dependently inhibited baseline reflexes and wind-up in normal and carrageenan preparations, whereas indomethacin (100-300 microM) had no effect. Thus meloxicam inhibits spinal reflexes, whereas indomethacin does not, despite its high affinity for both COX isoforms. We conclude that meloxicam has spinal antinociceptive actions which cannot be explained by the current concept of COX inhibition.  相似文献   
94.
An isocratic high-performance liquid chromatographic method with ultraviolet detection was utilized for the investigation of the pharmacokinetics of naringenin and its glucuronide conjugate in rat plasma and brain tissue. Plasma and brain tissue were deproteinized by acetonitrile, then centrifuged for sample clean-up. The drugs were separated by a reversed-phase C18 column with a mobile phase consisting of acetonitrile-orthophosphoric acid solution (pH 2.5-2.8) (36:64, v/v). The detection limits of naringenin in rat plasma and brain tissue were 50 ng/ml and 0.4 microg/g, respectively. The glucuronide conjugate of naringenin was evaluated by the deconjugated enzyme beta-glucuronidase. The naringenin conjugation ratios in rat plasma and brain tissue were 0.86 and 0.22, respectively, 10 min after naringenin (20 mg/kg, i.v.) administration. The mean naringenin conjugation ratio in plasma was approximately four fold that in brain tissue.  相似文献   
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In order to study the functional development of a thymus in an experimental model, small pieces of adult rat thymic tissue were cultured for 9 days and implanted under the kidney capsule of littermates. The tissues were examined with a panel of antibodies raised against thymic and neural factors and neural crest cells at intervals from 5 to 13 days. At 5 days post-implantation, there were groups of L1+ cells within the implants that reacted with antibodies raised against neural and neural crest cell markers. L1+ cells were highly mitotic, rounded cells measuring 8.7 +/- 0.6 micrometer in diameter. Double immunostaining with different combinations of antibodies showed that 94% of the L1+ cells were also TH+, and many were HNK-1/NCAM+, PGP 9.5+, NGF+, chromogranin A+, VIP+, S100+, CGRP+, GAD+, and A2B5+. A few were also pan-cytokeratin+. These results indicate that these cells are derived from neural crest derived cells and belong to the neuroepithelial line of development. The L1+ cells were most numerous before nerves appeared (about Day 9) and reduced in number and extent as the thymus differentiated. The neural crest cells occasionally had long cytoplasmic extensions, but it was not possible to decide if they formed the nerves that appeared in the implants. Adult thymuses also contained a population of L1+ and HNK-1/NCAM+ cells, mainly in the subcapsular cortex, the septa, and the medulla. These cells could be a source of neural crest cells able to repopulate the implant. The adult thymus may always contain a reservoir of cells potentially capable of producing neuropeptides and transmitter factors required for thymic growth and regeneration.  相似文献   
98.
BACKGROUND: Although neuromuscular blocking agents do not cross the blood-brain barrier, they may penetrate the central nervous system under particular circumstances and eventually cause neurotoxic consequences. METHODS: The effects of neuromuscular blocking agents on excitatory and inhibitory transmission in area CA1 of rat hippocampal slices were investigated using extracellular and intracellular recording techniques. RESULTS: Application of atracurium in the perfusion medium resulted in a dose-dependent enhancement of excitatory synaptic responses averaging 48.7 +/- 4.3% at a concentration of 10 nM. This effect was correlated with an increase in the size of the presynaptic fiber volley. Laudanosine, but not pancuronium bromide or vecuronium bromide, produced similar changes. In addition, atracurium and laudanosine blocked inhibitory transmission and reduced intracellularly recorded gamma-aminobutyric acidA receptor-mediated potentials. These effects were observed only at concentrations >1 microM and were not reproduced by pancuronium bromide and vecuronium bromide. CONCLUSIONS: Atracurium and its metabolite, laudanosine, contrary to pancuronium bromide and vecuronium bromide, produce two distinct effects on hippocampal slices. They enhance excitatory transmission and neuronal excitability and they block inhibitory gamma-aminobutyric acidA-mediated synaptic responses.  相似文献   
99.
The nutritional status of 75 maintenance hemodialysis (MHD) patients was evaluated according to the dietary intake analysis, anthropometric measurements, biochemical and immunological parameters in this study. Furthermore, some possible factors which would affect nutritional status of hemodialysis patients were discussed. The results showed that hemodialysis patients demonstrated a high incidence of malnutrition. The low intake of protein and calorie, metabolic acidosis and inadequate dialysis would worsen the malnutrition while erythropoietin treatment improve the nutritional status of hemodialysis patients. Based on these results, suggestions were proposed for the improvement of nutritional status of MHD.  相似文献   
100.
FC Wei  HC Chen  CC Chuang  SH Chen 《Canadian Metallurgical Quarterly》1994,93(2):345-51; discussion 352-7
Microsurgical toe transfer is an established method for reconstruction of missing thumbs. However, there is little agreement on which of the various techniques represents the ideal transfer. Basically, selection of technique requires balancing the patient's functional needs, appearance of the reconstructed thumb, and donor-site cosmesis. Based on our experience with 103 toe-to-thumb transfers performed over the past 9 years, this paper attempts to provide guidelines for appropriate selection among the four most commonly employed toe transfer techniques (e.g., second toe, total great toe, great toe wrap-around, trimmed great toe) so that optimal results and patient's acceptance can both be achieved.  相似文献   
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