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981.
The lived experience of clinical educators   总被引:1,自引:0,他引:1  
This phenomenological study was undertaken to discover the everyday meanings which clinical educators of pre-registration Bachelor of Nursing students attached to their experiences as clinical educators The researcher employed a qualitative design using audiotaped in-depth interviews with four registered nurses employed as clinical educators in four different schools of nursing in Victoria, Australia Using hermeneutics, thematic analysis revealed five themes of meaning central to the lived experiences of clinical educators They are (a) being human, (b) having standards, (c) developing own teaching style, (d) learn as you go, and (e) not belonging The first three themes are described in the literature on clinical education, however, the latter two are unique to this research The results of this study indicate there is need for extensive preparation and on-going support of clinical educators The researcher, who is respectful of the enormity of the task which educators face in preparing students for practice, speculates whether clinical educators are the vanguards of student learning in the clinical field It is evident that the participants of this study did not possess many of the role requirements of clinical educators identified in the literature Further studies are needed which explore the link between student learning and clinical educator support  相似文献   
982.
A total of 15 mixtures involving 9 different stocks attributed to the 19/20, 32 and 39 major clonal genotypes of Trypanosoma cruzi were used to infect third-instar nymphs of Triatoma infestans via an artificial feeding device. Three biological parameters were considered: (1) the percentage of infected insects (%II), (2) the number of flagellates per insect (NFI), and (3) the percentage of trypomastigotes per insect (%DIF). Genetic characterization by both multilocus enzyme electrophoresis (MLEE) and random amplification of polymorphic DNA (RAPD) indicated that in almost all cases (87%), mixtures remained present after completion of the whole cycle in the insect vector. Two lines of comparison were performed: (1) pure clonal genotypes versus corresponding mixed clonal genotypes and (2) the␣actual behavior of mixed clonal genotypes versus the expected behavior of the theoretical mixture (i.e. the␣arithmetic mean of the results observed for each of the two clonal genotypes taken separately). Statistical analyses of the variables were made difficult because of the presence of large standard deviations. Nevertheless, in several cases, mixtures differed significantly from pure clonal genotypes, and in one case the actual mixture differed significantly from the theoretical mixture. In some cases, interaction (either potentialization or reciprocal inhibition) could be suspected. Received: 10 March 1997 / Accepted: 21 September 1997  相似文献   
983.
Study Objective . To compare the pharmacokinetics of a single 100-mg oral dose of itraconazole administered as 10 ml of a 10-mg/ml itraconazole solution in hydroxypropyl-β-cyclodextrin under fasting versus postprandial conditions. Design . Open-label, two-way, randomized, crossover study. Setting . Janssen Research Foundation, Belgium. Patients . Twelve healthy volunteers. Interventions . Blood samples were obtained for pharmacokinetic analyses immediately before dosing and at regular intervals up to 96 hours after each dose. Blood and urine samples were obtained for hematologic, biochemical, and urinary safety analyses at baseline and at the end of the study. Measurements and Main Results . The mean peak plasma concentrations of both itraconazole and its active metabolite hydroxy-itraconazole were significantly higher under fasting conditions than under postprandial conditions. The mean times to peak concentration for both the parent compound and its metabolite were significantly shorter under fasting than under nonfasting conditions. The mean areas under the curve (AUC0–∞ and AUC0–24 hrs) were also significantly higher under fasting than under postprandial conditions. Conclusions . Our findings suggest that the higher bioavailability of this new formulation of itraconazole may be of benefit in seriously ill patients who are not able to ingest adequate quantities of food. The fact that the solution was also well tolerated and was not associated with clinically significant changes in any laboratory value further underscores the potential utility of this dosing form.  相似文献   
984.
985.
So far, laparoscopic approaches to kidney and adrenal have been limited because of their retroperitoneal location. We here report eight renal and adrenal endoscopic procedures performed in seven patients: two adrenalectomies for hyperaldosteronism, one adrenalectomy for isolated metastasis from an adenocarcinoma of the lung; two nephrectomies for end-stage infected hydronephrosis, two partial nephrectomies for small circumscribed lesions of the kidney, and one endoscopic resection for pain relief of a voluminous cyst at the kidney. The approach was transperitoneal in two cases and retroperitoneal in five cases using the retropneumoperitoneum insufflation technique. One patient was operated by a combined approach using the retro- and transperitoneal routes. All procedures were successfully completed endoscopically. The retroperitoneoscopic approach of the kidney is safe and does not interfere with the peritoneal organs. Its working space is tenuous, but allows a direct access on the kidney with good exposure of its pedicle. For adrenal surgery, the retroperitoneoscopic dissection is more difficult, because movements of instruments are often impaired by the closeness of the costal margin and the iliac crest. However, in case of difficulties we found it very convenient to switch from a retroperitoneal endoscopic approach to a combined coelioscopic and retroperitoneoscopic operation. Far from excluding each other, both approaches are complementary, particularly for difficult situations (i.e., previous peritoneal or retroperitoneal surgery).  相似文献   
986.
W de Smet  H Walter    L van Hove 《Immunology》1993,79(1):46-54
We describe a monoclonal antibody (mAb), designated 1.C1, that causes rapid and vigorous aggregation among normal leucocytes and among T and myeloid/monocytic cell lines. As shown by competitive binding and sequential immunoprecipitation experiments, the antigen recognized by mAb 1.C1 is a 115,000 MW sialoglycoprotein, that corresponds to the human CD43 antigen, also known as leukosialin or sialophorin. The aggregation process starts within minutes and reaches maximum level 6-18 hr after addition of the antibody. It is dependent on active cell metabolism (inhibited at low temperatures and by a mixture of the metabolic poisons azide and 2-deoxy-D-glucose), a fluid plasma membrane (inhibited by pretreatment of the cells with paraformaldehyde) and an intact cytoskeleton (inhibited by cytochalasin B). Two reference CD43 antibodies (MEM-59 and DF-T1), both binding the same or closely related sialic acid-dependent epitope as mAb 1.C1, are also capable of inducing cell clump formation. CD11a/CD18 mAb block the 1.C1-induced adhesion of resting peripheral blood leucocytes, but not of haematopoietic cell line cells. In addition, mAb 1.C1 induces homotypic aggregation of K-562 cells, which do not express members of the beta 2 integrin subfamily on their surface. These data suggest that triggering of the CD43 antigen promotes homotypic cell adhesion that is mediated by both CD11a/CD18-dependent and -independent pathways.  相似文献   
987.
988.
Thermal injury sustained during pregnancy presents special management problems for the gravid woman and her unborn child. Because of the reported high morbidity and mortality and lack of available data in South Africa, a multicentre retrospective review was undertaken by five burn centres. Thirty-three patients (average age 25,7 years) with mean 30% (range 1-80%) total body surface area burn were assessed. A review of the clinical material led to the following observations and conclusions. Pregnancy does not influence maternal outcome after thermal injury and maternal survival is usually accompanied by fetal survival in the absence of significant maternal complications. Maternal survival is less likely if the burn wound exceeds 50% total body surface area. Thermal injury does increase the risk of spontaneous abortion and premature labour, and fetal survival depends on fetal maturity. Early obstetric intervention is only indicated in the gravely ill patient where complications (hypoxia, hypotension, sepsis) jeopardize the life of a viable fetus. The mode of delivery should be determined by obstetric considerations.  相似文献   
989.
990.
Efficacy of Intraoperative Cooling Methods   总被引:3,自引:0,他引:3  
Background: Patients may require perioperative cooling for a variety of reasons including treatment of a malignant hyperthermia crisis and induction of therapeutic hypothermia for neurosurgery. The authors compared heat transfer and core cooling rates with five cooling methods.

Methods: Six healthy volunteers were anesthetized with desflurane and nitrous oxide. The cooling methods were 1) circulating water (5 [degree sign] Celsius, full-length mattress and cover), 2) forced air (10 [degree sign] Celsius, full-length cover), 3) gastric lavage (500 ml iced water every 10 min), 4) bladder lavage (300 ml iced Ringer's solution every 10 min), and 5) ice-water immersion. Each method was applied for 40 min or until the volunteers' core temperatures approached 34 [degree sign] Celsius. The volunteers were rewarmed to normothermia between treatments. Core cooling rates were evaluated using linear regression.

Results: The first volunteer developed abdominal cramping and diarrhea after gastric lavage. Consequently, the technique was not again attempted. Bladder lavage increased heat loss 10 [nearly =] 10 W and decreased core temperature 0.8 +/- 0.3 [degree sign] Celsius/h (r2 = 0.99 +/- 0.002; means +/- SD). Forced-air and circulating-water cooling comparably increased heat flux, [nearly =] 170 W. Consequently, core cooling rates were similar during the two treatments at 1.7 +/- 0.5 [degree sign] Celsius/h (r2 = 0.99 +/- 0.001) and 1.6 +/- 1.1 [degree sign] Celsius/h (r2 = 0.98 +/- 0.02), respectively. Immersion in an ice water slurry increased heat loss [nearly =] 600-800 W and decreased core temperature 9.7 +/- 4.4 [degree sign] Celsius/h (r sup 2 = 0.98 +/- 0.01). Immersion cooling was associated with an afterdrop of [nearly =] 2 [degree sign] Celsius.  相似文献   

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