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41.
OBJECTIVE: To formulate the fundamental structure of caring as lived by Critical Care Nurses. DESIGN: Colaizzi's phenomenological research method and Diekelmann's dialogue technique were applied. SETTING: The home of each nurse constituted the setting for the interview. The nurses were employed in critical care units in six large metropolitan hospitals in the Southwest. SAMPLE: The availability sample consisted of 15 female critical care registered nurses. The nurses' mean age was 35 years. The mean number of years in critical care nursing was 4.7. One nurse was Asian, one was Hispanic, and 13 were Caucasian. RESULTS: Caring was composed of affective, cognitive, action, and outcome subprocesses. The caring process originated in the nurse's feelings and knowledge, and moved the nurse to competent actions that contributed to patient, family, and nurse outcomes. CONCLUSIONS: Understanding of the process of caring was strengthened by the findings. The decision process used by nurses would benefit from further examination for the presence of the affective and nurse outcome subprocesses. 相似文献
42.
DD Baird AJ Wilcox CR Weinberg F Kamel DR McConnaughey PI Musey DC Collins 《Canadian Metallurgical Quarterly》1997,12(12):2607-2613
We compared daily urinary concentrations of oestrogen and progesterone metabolites in paired menstrual cycles (conception and non-conception) from 32 women. Volunteers with no known fertility problems were enrolled in the study at the time they began trying to become pregnant. They collected first-morning urine specimens and kept daily records of menstrual bleeding and sexual intercourse for 6 months or until they became clinically pregnant. Intercourse in non-conception cycles was close to the time of ovulation so that failure to conceive was caused by factors other than poorly timed intercourse. Compared with non-conception cycles, conception cycles had a steeper early luteal rise in progesterone and higher mid-luteal oestrogen and progesterone concentrations. These hormonal characteristics may be markers of better quality cycles, but because all these differences were in the luteal phase, we cannot rule out the possibility that the preimplantation embryo had stimulated early increases in steroid production. We propose an analysis strategy that could help support or refute the importance of preimplantation embryonic signalling, but our small sample size limits our own conclusions about this mechanism. 相似文献
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SQ Cheng XD Zhou ZY Tang Y Yu SS Bao DC Qian 《Canadian Metallurgical Quarterly》1997,123(11-12):639-644
The influence of the biological medium on high-intensity focused ultrasound (HIFU) therapy for ablating experimental liver cancer was studied. In study 1, the temperature rise in the focal zone in the presence of iodized oil or castor oil was observed in vitro. The results showed that HIFU with iodized oil produced a higher and faster temperature rise than did HIFU with castor oil, whether high-power (500 W/cm2) or relatively low-power (136 W/cm2) conditions were used (P = 0.0008 and P = 0.0004 respectively). With the excised liver samples, the temperature also rose higher and more rapidly after injection of iodized oil into the liver than when castor oil was injected (P = 0.0239), and the target liver tissue revealed more radically and extensive destruction with iodized oil than with castor oil. In study 2, 48 nude mice, bearing primary liver cancer LTNM4 implanted subcutaneously, were randomly divided into four groups. Group I (n = 12) were the controls, group II (n = 12) were injected with iodized oil alone, group III (n = 12) received HIFU treatment, and group IV (n = 12) were exposed to HIFU after iodized oil injection. Significant inhibition of tumor growth was seen in groups III and IV as compared with group I or group II (P < 0.05), the tumor growth inhibition rate on the 28th day after treatment being 87% and 93% respectively. Significantly improved survival was noted in groups III and IV compared with groups I and II (P < 0.05). Histologically, group IV showed more complete tumor necrosis than did group III. These data suggest that HIFU combined with iodized oil might have achieve of synergism, location and targeting in the treatment of liver cancer. 相似文献
48.
OH Suleiman BJ Conway P Quinn RG Antonsen FG Rueter RJ Slayton DC Spelic 《Canadian Metallurgical Quarterly》1997,203(2):471-476
PURPOSE: To determine the average abdominal entrance air kerma, low-contrast sensitivity, and spatial resolution in upper gastrointestinal tract fluoroscopy in the United States. MATERIALS AND METHODS: A random sample of fluoroscopic facilities was selected to be surveyed for the Nationwide Evaluation of X-ray Trends program. Measurements were performed by using a newly developed fluoroscopic phantom. The surveys were conducted by state radiation control personnel. RESULTS: Average air kerma rates 1 cm above the tabletop, free in air, were 43 mGy/min (n = 340). The rate increased to 64 mGy/min when a 1.6-mm-thick copper filter, which simulated the use of barium contrast medium, was added to increase attenuation. The average entrance air kerma, free in air, for radiographs was 3.4 mGy, and an average of 12 radiographs were obtained per examination. Of 352 facilities surveyed, 306 (87%) were able to resolve wire mesh with 20 or more lines per inch. Of 339 facilities for which percentage contrast could be calculated, 192 (57%) had minimum percentage contrast values of 4% or more. CONCLUSION: Spatial resolution for fluoroscopy is adequate for most of the facilities surveyed, but a substantial proportion of facilities could not visualize low-contrast test objects, which strongly suggests image quality problems. 相似文献
49.
BM Léonard F Hétu L Busque M Gyger R Bélanger C Perreault DC Roy 《Canadian Metallurgical Quarterly》1998,91(1):331-339
The suppressor of Hairy-wing [SU(HW)] binding region disrupts communication between a large number of enhancers and promoters and protects transgenes from chromosomal position effects. These properties classify the SU(HW) binding region as an insulator. While enhancers are blocked in a general manner, protection from repressors appears to be more variable. In these studies, we address whether repression resulting from the Polycomb group genes can be blocked by the SU(HW) binding region. The effects of this binding region on repression established by an Ultrabithorax Polycomb group Response Element were examined. A transposon carrying two reporter genes, the yellow and white genes, was used so that repression and insulation could be assayed simultaneously. We demonstrate that the SU(HW) binding region is effective at preventing Polycomb group repression. These studies suggest that one role of the su(Hw) protein may be to restrict the range of action of repressors, such as the Polycomb group proteins, throughout the euchromatic regions of the genome. 相似文献
50.
J Romagnuolo DC Sadowski E Lalor L Jewell AB Thomson 《Canadian Metallurgical Quarterly》1998,12(7):479-483
PURPOSE: The goal of this study is to describe asymmetrical forms of primary open angle glaucomas in black african originated patients. MATERIAL AND METHOD: Data of 514 glaucomatous patients (1022 eyes) followed between 1993 and 1997, and attending our hospital eye department are retrospectively analysed. All the participants were diagnosed as primary open angle glaucomas; asymetry was defined as a difference of 0.2 at least between the vertical cup disc ratio of the same patient. RESULTS: The mean age of all 514 glaucoma patients was 34.52 +/- 15.55 years; 254 patients (49.40%) had no differences between cup disc values while 260 remaining others had asymmetric glaucomas (50.58%). Of them, 189 (72.69%) had a difference of 0.2 between both eyes; 49 (18.8%) had 0.3 difference; 7 (2.69%) had 0.4 difference; 4 (1.53%) had 0.5 difference, and 11 (4.23%) a difference of 0.6. Besides, 114 eyes (11.15%) had a vertical ratio of 0.9 at the first diagnosis. CONCLUSION: Carefully recognition of asymmetric cup disc ratios is of great diagnostic value in the the early stages of primary open angle glaucoma because 50% of all patients presented with this clinical form in our experience. This strategy would improve early diagnosis of glaucoma in our areas. 相似文献