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61.
This is the first of two papers which address aspects of the findings of a large scale study commissioned by the English National Board which set out to examine the impact of Project 2000 on perceptions of the philosophy and practice of nursing. The findings presented here suggest that there have been fundamental shifts in perceptions of the nature and discipline of nursing. Students and diplomates of the course perceive themselves as knowledgeable doers, with their practice well grounded in theory and research. They value the interpersonal skills teaching and place the patient firmly at the centre of care delivery, viewing the patient holistically and being prepared to be fierce patient advocates where necessary. It is difficult to determine the extent to which these shifts can be attributed to the Project 2000 course, although the Project 2000 approach to education appears to be an important factor.  相似文献   
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OBJECTIVE: To test the hypothesis that inhibition of protein kinase (PK) activity or proteolysis inhibits ovulation. DESIGN: Rats were injected intrabursally with protein kinase (H9 or staurosporin) or proteinase (alpha 2-macroglobulin) inhibitors and oocyte release was evaluated. SETTING: Clinical Research Laboratory, Center for Reproductive Medicine, University of Kentucky Medical Center. PARTICIPANTS: Immature rats stimulated with pregnant mare serum gonadotropin. INTERVENTIONS: Staurosporin (1 or 10 microM), H9 (1 mM), alpha 2-macroglobulin (835 microIU of activity); or vehicle was injected into the right ovarian bursa. The left ovarian bursa remained intact. Animals immediately received human chorionic gonadotropin (hCG). MAIN OUTCOME MEASURES: Analysis of oocyte release and ovarian morphology. RESULTS: Oocyte release from the inhibitor-treated side decreased for the H9 group (8.1 +/- 1.9 fewer oocytes released, P less than 0.001) and the 10 microM staurosporin group (5.5 +/- 0.6, P less than 0.001). No change in oocyte release was observed in the 1 microM staurosporin, alpha 2-macroglobulin, or vehicle injected groups. Histologic examination of vehicle treated ovaries demonstrated numerous developing corpora lutea (CL; 20.5 +/- 2.1 CL/ovary) and a lack of preovulatory follicles. In contrast, ovaries treated with PK inhibitors contained unruptured preovulatory follicles coincident with fewer forming CL (11.5 +/- 3.5 CL/ovary). CONCLUSIONS: Inhibition of PK activity in vivo suppresses ovulation, demonstrating that protein phosphorylation plays an important intermediary role in the ovulatory process.  相似文献   
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We studied CFU-GM recovery from bone marrow samples frozen either in a machine for controlled-rate freezing or in a -70 degrees C freezer. We found no statistically significant difference between the two methods. Cooling-curve investigations also demonstrated that it was possible to obtain satisfactory cooling rates simply by manipulation of the shape and volume of the marrow and its container. Five patients received a total of six successful autografts for which their marrow cells were frozen without controlled-rate freezing. Thus it is not necessary to use a sophisticated machine in order to obtain satisfactory cryopreservation of human marrow stem cells.  相似文献   
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BACKGROUND AND PURPOSE: Neutrophils are critically involved with ischemia and reperfusion injury in many tissues but have not been studied under conditions of reperfusion after focal cerebral ischemia. The present studies were conducted to confirm our previous observations quantifying neutrophils in rat permanent focal stroke using a myeloperoxidase activity assay and to extend them to transient ischemia with reperfusion. In addition, leukotriene B4 receptor binding in ischemic tissue was evaluated as a potential marker for inflammatory cell infiltration. METHODS: Histological, enzymatic, and receptor binding techniques were used to evaluate neutrophil infiltration and receptor binding in infarcted cortical tissue 24 hours after permanent middle cerebral artery occlusion (n = 25) or temporary occlusion for 80 (n = 12) or 160 (n = 22) minutes followed by reperfusion for 24 hours in spontaneously hypertensive rats. RESULTS: Sham surgery (n = 26) produced no changes in any parameter measured. After permanent middle cerebral artery occlusion, neutrophil accumulation was observed histologically, but the infiltration was moderate and typically within and adjacent to blood vessels bordering the infarcted cortex. After temporary middle cerebral artery occlusion with reperfusion, marked neutrophil infiltration was observed throughout the infarcted cortex. Myeloperoxidase activity was increased (p less than 0.05) after permanent occlusion and to a greater extent after temporary occlusion with reperfusion. Myeloperoxidase activity (units per gram wet weight) in ischemic cortex was increased over that in nonischemic (control) cortex 32.2-fold, 54.6-fold, and 92.1-fold for permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (p less than 0.05). Sham surgery produced no changes in myeloperoxidase activity. Leukotriene B4 receptor binding also was increased (p less than 0.05) after focal ischemia and paralleled the increases in myeloperoxidase activity. Ischemic cortex-specific receptor binding (femtomoles per milligram protein) was 3.87 +/- 0.63 in sham-operated rats and 4.57 +/- 0.98, 8.98 +/- 1.11, and 11.12 +/- 1.63 for rats subjected to permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (all p less than 0.05 different from sham-operated). Cortical myeloperoxidase activity was significantly correlated with the degree of cortical leukotriene B4 receptor binding (r = 0.66 and r = 0.79 in two different studies, p less than 0.01). CONCLUSION: These data indicate that neutrophils are involved in focal ischemia and that there is a dramatic accumulation of neutrophils in infarcted tissue during reperfusion that can be quantified using the myeloperoxidase activity assay. Leukotriene B4 receptor binding increases in infarcted tissue in a parallel manner, which suggests that the increased leukotriene B4 binding is to receptors located on the accumulating neutrophils.  相似文献   
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Adherence of bacteria to corneal epithelium is a prerequisite for corneal infection. We used two methods to study the binding of Pseudomonas aeruginosa and Staphylococcus aureus to rabbit corneal epithelial cells in culture. In the first method, rabbit corneal epithelial cells grown on glass slides were incubated with P. aeruginosa or S. aureus (10(7) CFU/ml) at room temperature for 90 min, and the bacterial binding to the epithelial cells was examined by light microscopy. Both P. aeruginosa and S. aureus bound to epithelial cells. P. aeruginosa was bound to the cell periphery whereas S. aureus was bound randomly to the cell surface. In the second method, suspension cultures of corneal epithelial cells were used. In contrast to the findings in cultures on slides, binding pattern with cells in suspension was similar for both species and resembled that for S. aureus in cultures on slides. A much greater number of P. aeruginosa (186 +/- 11 bacteria/epithelial cell) than S. aureus (30 +/- 1.5 bacteria/epithelial cell) bound to epithelial cells grown on glass slides. In contrast, a similar number of P. aeruginosa (25 +/- 5.1) and S. aureus (20 +/- 4.7) bound to epithelial cells grown in suspension cultures. Using either method, Escherichia coli and Streptococcus pyogenes did not bind significantly (less than 5/cell) to corneal epithelial cells. The above methods should prove useful for characterization of bacterial binding to corneal epithelial cells in culture.  相似文献   
69.
Seventeen consecutive patients were referred for management of empyema between April 1991 and March 1992. Fourteen patients defined as having an 'early' empyema were initially treated by videothoracoscopy. The other three patients, defined as having a 'late' empyema proceeded directly to thoracotomy. Videothoracoscopy was successful in 10 out of the 14 patients. The mean postoperative stay was 7.8 days. At a mean follow-up at 16.7 months, these patients were rendered apyrexial with full lung expansion and no residual pleural collection. The postoperative results were at least equivalent to other conventional forms of treatment without an undue level of complications. In this series, thoracoscopy was found to be successful when symptoms had been present up to 31 days before presentation at the first hospital, and the mean length of treatment before referral to Harefield was 47 days. It is now our policy to videothoracoscope all patients with empyema thoracis, regardless of the length of referral. It may circumvent the need for a thoracotomy, it does not add any increased risk of complications, and does not appreciably increase the length of hospital stay should thoracotomy ultimately be required.  相似文献   
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