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21.
The concept of transcultural nursing is relatively new to the nursing literature. It had been less than 30 years since Madeleine Leininger first began to develop a theory of transcultural nursing as part of a doctoral study in anthropology. Much has changed in that time, and nursing staff development and inservice educators need to provide educational offerings within a multicultural context in a timely manner. Cultural diversity is the standard in the mid-1990s, and those nursing staff development programs that are sensitive to this fact produce employees with advantages over those from settings that do not prepare staff for practice in a constantly changing world. This annotated bibliography about transcultural nursing details key references for staff development and inservice programs. It is not intended as an exhaustive review but rather focuses on the most relevant, timely, and useful of the ever increasing number of publications concerning this important subject. Six major books and four of the most pertinent recent journal articles are included. Conclusions and implications for nursing staff educators are offered. 相似文献
22.
JB Prins CU Niesler CM Winterford NA Bright K Siddle S O'Rahilly NI Walker DP Cameron 《Canadian Metallurgical Quarterly》1997,46(12):1939-1944
Tumor necrosis factor-alpha (TNF-alpha) production by adipocytes is elevated in obesity, as shown by increased adipose tissue TNF-alpha mRNA and protein levels and by increased circulating concentrations of the cytokine. Furthermore, TNF-alpha has distinct effects on adipose tissue including induction of insulin resistance, induction of leptin production, stimulation of lipolysis, suppression of lipogenesis, induction of adipocyte dedifferentiation, and impairment of preadipocyte differentiation in vitro. Taken together, these effects all tend to decrease adipocyte volume and number and suggest a role for TNF-alpha in limiting increase in fat mass. The aim of the present study was to determine if TNF-alpha could induce apoptosis in human adipose cells, hence delineating another mechanism by which the cytokine could act to limit the development of, or extent of, obesity. Cultured human preadipocytes and mature adipocytes in explant cultures were exposed in vitro to human TNF-alpha at varying concentrations for up to 24 h. Apoptosis was assessed using morphological (histology, nuclear morphology following acridine orange staining, electron microscopy) and biochemical (demonstration of internucleosomal DNA cleavage by gel electrophoresis and of annexin V staining using immunocytochemistry) criteria. In control cultures, apoptotic indexes were between 0 and 2.3% in all experiments. In the experimental systems, TNF-alpha induced apoptosis in both preadipocytes and adipocytes, with indexes between 5 and 25%. Therefore, TNF-alpha induces apoptosis of human preadipocytes and adipocytes in vitro. In view of the major metabolic role of TNF-alpha in human adipose tissue, and the knowledge that adipose tissue is dynamic (with cell acquisition via preadipocyte replication/differentiation and cell loss via apoptosis), these findings describe a further mechanism whereby adipose tissue mass may be modified by TNF-alpha. 相似文献
23.
AI Kassis PY Wen AD Van den Abbeele J Baranowska-Kortylewicz GM Makrigiorgos KR Metz KZ Matalka CU Cook SK Sahu PM Black SJ Adelstein 《Canadian Metallurgical Quarterly》1998,39(7):1148-1154
Glial neoplasms of the human central nervous system have defied treatment, in part because of the limited selectivity of available cytotoxic agents. The thymidine analog 5-iodo-2'-deoxyuridine radiolabeled with the Auger electron emitter 125I (125IUdR) is highly toxic to dividing cells when it is deoxyribonucleic acid incorporated, but it is relatively innocuous when located outside the nucleus. Previous studies have shown that 125IUdR has significant antineoplastic potential against mammalian cells in vitro and direct administration of 125IUdR is effective therapy for ovarian ascites tumors in mice and neoplastic meningitis in rats. Studies using external gamma imaging and autoradiography have also shown that direct intratumoral administration of 123IUdR/125IUdR into intracerebral 9L gliosarcomas in rats results in selective uptake of the radionuclide into tumor cells. Based on these encouraging results, we have evaluated the therapeutic potential of 125IUdR in rats bearing intracerebral 9L gliosarcomas. METHODS: Iodine-125-IUdR was infused intracerebrally over a 2-day period into rats bearing 1-day-old 9L tumors and over a 6-day period into animals with 9-day-old 9L tumors; equimolar concentrations of 127IUdR were infused into control animals. Tumor growth was monitored by contrast-enhanced 1H MRI and animal survival was followed over time. RESULTS: Intracerebral tumors (3-7 mm) were readily detected by MRI. Tumor-bearing rats treated with 127IUdR succumbed within 17-24 days, whereas tumor-bearing animals treated with 125IUdR survived significantly longer, and 10%-20% of the animals were cured of tumors. CONCLUSION: These data substantiate the antineoplastic potential of 5-[125I]iodo-2'-deoxyuridine and indicate that it may be a useful agent for the therapy of solid tumors that are accessible to direct radiopharmaceutical administration. 相似文献
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LW Frick CU Lambe L St John LC Taylor DJ Nelson 《Canadian Metallurgical Quarterly》1994,38(12):2722-2729
(2'R,5'S-)-cis-5-Fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl] cytosine (524W91) is a nucleoside analog with potent anti-human immunodeficiency virus and anti-human hepatitis B virus activities in vitro. The pharmacokinetics and bioavailability of 524W91 after oral dosing were studied in mice dosed with 10, 100, and 600 mg of 524W91 per kg of body weight by the oral and intravenous routes. Cynomolgus monkeys were dosed with 10 and 80 mg of 524W91 per kg. In both species, the clearance of 524W91 was rapid, via the kidney, and was independent of dose. In monkeys, the total body clearance of 10 mg of 524W91 per kg was 0.7 +/- 0.1 liter/h/kg, and the volume of distribution at steady state was 0.8 +/- 0.02 liter/kg. The terminal elimination half-life was 1.0 +/- 0.2 h. The absolute bioavailability after oral dosing was 63% +/- 4% at 10 mg/kg. Concentrations of 524W91 in the cerebrospinal fluid were 4% +/- 0.7% of the corresponding levels in plasma. In mice, the total clearance of 10 mg of 524W91 per kg was 2.3 liters/kg/h, and the volume of distribution at steady state was 0.9 liter/kg. Absolute bioavailability in mice after oral dosing was 96% at a dose of 10 mg/kg. The metabolism of orally administered [6-3H]524W91 was studied in cynomolgus monkeys at a dose of 80 mg/kg and in mice at a dose of 120 mg/kg. Monkeys excreted 41% +/- 6% of the radioactive dose in the 0- to 72-h urine, 33% +/- 10% in the feces, and 10% +/- 7% in the cage wash. Unchanged 524W91 was 64% of the total radiolabeled drug recovered in the urine. The glucuronide was a minor urinary metabolite. 5-Fluorouracil was not detected (less than 0.02% of the dose). Mice dosed orally with 120 mg of [6-3H]524W91 per kg excreted 67% +/- 7% of the radiolable in the )- to 48-h urine. Small amounts of the 3' -sulfoxide and glucuronide metabolites were observed in the urine, but 5-fluorouracil was not detected. Good bioavailability after oral dosing and resistance to metabolism recommend 524W91 for further preclinical evaluation. 相似文献
26.
REC114 is one of 10 genes known to be required for the initiation of meiotic recombination in Saccharomyces cerevisiae. It is transcribed only in meiosis, and our previous sequence analysis suggested the presence of an intron in the 3' end of the gene. Hypotheses in the literature have suggested, because of its unusual location, either that the putative intron in REC114 is likely to be necessary for expression, or that there may actually be no intron present. This work demonstrates that REC114 does have an intron and is one of only three genes in yeast with introns located in the 3' end. Furthermore, the 3' splice site utilized in REC114 is a very rare AAG sequence; only three other genes in yeast use this nonconsensus sequence. The splicing of REC114 does not require MER1, a gene known to be involved in meiosis-specific RNA processing. In fact, an intronless copy of REC114 can complement a null rec114 mutation. Thus, it does not appear that the intron is essential for expression of REC114. Although the intron is not absolutely required for meiotic function, it is conserved in evolution; two other species of yeast contain an intron at the same location in their REC114 genes. 相似文献
27.
Michael V. Phillips George E. Ramey David W. Pittman 《Canadian Metallurgical Quarterly》1997,2(4):176-182
Because drying shrinkage cracking is a major source of bridge deck cracking, and because shrinkage compensating concrete (SCC) is known to substantially reduce shrinkage cracking, the use of SCC should be closely examined in an effort to increase the durability and service life of bridge decks. One of the concerns regarding the use of SCC is its more demanding construction requirements for placement time and for curing. This paper addresses relevant material and construction issues that have resulted in the successful use of SCC for bridge decks. The Ohio Turnpike Commission (OTC) has used SCC exclusively for its new and replacement bridge decks for the past 12 years, and they have been very satisfied with its performance to date. The OTC's evaluation of SCC is that it greatly mitigates shrinkage cracking. The OTC's requirements for SCC at the concrete plant, in-transit, and at the job site are included in this paper. The OTC's construction procedures are presented in the form of a chronological sequence of photographs illustrating the construction activities on a new SCC deck placement in 1994. 相似文献
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F Guadagni M Roselli M Cosimelli A Spila F Cavaliere R Arcuri R D'Alessandro PL Fracasso V Casale A Vecchione CU Casciani JW Greiner J Schlom 《Canadian Metallurgical Quarterly》1997,72(6):949-954
Tissues and sera from 110 patients diagnosed with colorectal primary carcinoma, 20 patients with benign colorectal diseases and 31 healthy donors were subjected to quantitative CEA analysis. Multiple samples from tumor lesions and autologous histologically normal mucosa (10 cm from the tumor) were obtained at the time of surgery (cancer patients) or endoscopy (benign patients and healthy volunteers). CEA content was measured in protein extracts obtained from these tissues using a quantitative RIA method. A limit of normality for CEA content was established as 300 ng/mg of protein. When this was taken as cut-off, 104 of 110 (94.5%) tumor lesions and 51 of 110 (46.4%) autologous histologically normal colonic mucosa from cancer patients had elevated CEA levels. No correlation with stage of disease was found, while a correlation was observed with degree of tumor differentiation. A statistically significant difference between CEA content in tumor lesions and in histologically normal mucosa from cancer patients was observed (p = -0.001). Moreover, CEA content was statistically higher in the normal mucosa from cancer patients than in that from healthy donors (p = 0.005). CEA content in tissue specimens from benign lesions differed significantly from that in tissue from healthy donors (p = 0.005) and in carcinoma lesions (p < 0.001). The highest CEA content was observed in benign lesions with severe dysplasia. No statistical correlation between CEA content in carcinoma tissues and serum CEA levels (r = 0.195, p = .13) was found. Therefore, in considering diagnosis or therapy with anti-CEA MAbs for colorectal-carcinoma patients, or potential therapies with anti-CEA recombinant vaccines, serum CEA levels should not be taken as indicating CEA expression in tumor lesions. 相似文献