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71.
Ensuring the competency of staff members at all levels of practice is an ongoing challenge for perioperative clinical educators. The authors developed a competency-based orientation program using AORN's perioperative nursing competency statements as a conceptual framework. The model also incorporates requirements from external regulatory agencies (e.g., the Joints Commission on Accreditation of Healthcare Organizations) that influence the direction of health care institutions seeking accreditation. The model provides the components necessary to validate the orientation of perioperative staff members and the delivery of comprehensive nursing care in perioperative settings. 相似文献
72.
CA O'Neill CL Stebbins S Bonigut B Halliwell JC Longhurst 《Canadian Metallurgical Quarterly》1996,81(3):1197-1206
Reactive oxygen species increase during exhaustive contraction of skeletal muscle, but characterization of the specific species involved and their rates of production during nonexhaustive muscle contraction have not been investigated. We hypothesized that the production rate of hydroxyl radical (.OH) increases in contracting muscle and that this rate is attenuated by pretreatment with deferoxamine (Def) or dimethylthiourea (DMTU). We measured the rate of production of .OH before, during, and after 5 min of intermittent static contraction of the triceps surae muscles in cats (n = 6) using the formation of p-, m-, and o-tyrosines by hydroxylation of phenylalanine. L-Phenylalanine (30 mg/kg i.v.) was administered to each animal 3 min before contraction. Blood samples were collected from the popliteal vein 1 min before contraction; 1, 3, and 4.5 min during contraction; and 1 min after contraction. During and after contraction, the cumulative production rates of p-, m-, and o-tyrosines were elevated by 42.84 +/- 5.41, 0.25 +/- 0.04, and 0.21 +/- 0.03 nmol.min-1.g-1, respectively, compared with noncontracting triceps surae muscles. Pretreatment with Def (10 mg/kg i.v.; n = 5) or DMTU (10 mg/kg i.v.; n = 4) decreased the cumulative rates of production of p-, m-, and o-tyrosines during and after contraction. Additionally, the rate of tyrosine production increased in proportion to the percentage of maximal tension developed by the triceps surae muscles. These results directly demonstrate that .OH is produced in vivo in the skeletal muscle of cats during intermittent static contraction and that production can occur before the onset of fatigue. 相似文献
73.
Prednisolone therapy of idiopathic feline lower urinary tract disease: a double-blind clinical study
CA Osborne JM Kruger JP Lulich GR Johnston DJ Polzin LK Ulrich J Sanna 《Canadian Metallurgical Quarterly》1996,26(3):563-569
A double-blind clinical study was performed to evaluate prednisolone as treatment for idiopathic feline lower urinary tract disease. No differences in response were observed in prednisolone- and placebo-treated cats. 相似文献
74.
75.
The authors attempted to confirm published reports that pentobarbital protects against radiation-induced damage to normal rat brain, as well as enhances radiotherapeutic efficacy in a rat brain tumor model. They evaluated animal survival in 9L gliosarcoma-burdened rats that received whole-brain radiation therapy (16, 24, 32, or 40 Gy) while under intraperitoneal pentobarbital (60 mg/kg) or intramuscular ketamine (60 mg/kg) sedation. The animals were examined at autopsy to attribute death to either intracranial tumor growth or normal brain toxicity in the absence of discernible tumor. There was no difference between the two anesthesia groups regarding the survival of unirradiated animals. Radiation therapy produced a significant dose-dependent prolongation in animal survival, which was limited by the development of normal tissue toxicity at the higher doses. When compared to ketamine anesthesia, pentobarbital anesthesia appeared to offer some protection (not statistically significant) against early (but not late) toxicity at selected radiation doses. A reduction in the number of deaths from tissue toxicity suggested an increased antitumor effect, but again this was not statistically significant. Only in one case was there even a marginal significant difference (p = 0.045) between overall therapeutic efficacy in rats sedated with pentobarbital versus ketamine. While there may be a radioprotective effect of pentobarbital in rat brains without intracranial tumor, there is no conclusive evidence for either radioprotection or significant improvement of radiotherapeutic efficacy in this 9L rat brain tumor model. 相似文献
76.
A new scheme based on using an IIR design algorithm is presented to demultiplex critically sampled QPSK channels for onboard processing (OBP) satellites. Comparisons with an existing nonrecursive (FIR) transmultiplexer (TMUX) show that the presented IIR TMUX is also a suitable candidate for consideration in future OBP applications 相似文献
77.
Apoptosis in the failing human heart 总被引:1,自引:0,他引:1
G Olivetti R Abbi F Quaini J Kajstura W Cheng JA Nitahara E Quaini C Di Loreto CA Beltrami S Krajewski JC Reed P Anversa 《Canadian Metallurgical Quarterly》1997,336(16):1131-1141
BACKGROUND: Loss of myocytes is an important mechanism in the development of cardiac failure of either ischemic or nonischemic origin. However, whether programmed cell death (apoptosis) is implicated in the terminal stages of heart failure is not known. We therefore studied the magnitude of myocyte apoptosis in patients with intractable congestive heart failure. METHODS: Myocardial samples were obtained from the hearts of 36 patients who underwent cardiac transplantation and from the hearts of 3 patients who died soon after myocardial infarction. Samples from 11 normal hearts were used as controls. Apoptosis was evaluated histochemically, biochemically, and by a combination of histochemical analysis and confocal microscopy. The expression of two proto-oncogenes that influence apoptosis, BCL2 and BAX, was also determined. RESULTS: Heart failure was characterized morphologically by a 232-fold increase in myocyte apoptosis and biochemically by DNA laddering (an indicator of apoptosis). The histochemical demonstration of DNA-strand breaks in myocyte nuclei was coupled with the documentation of chromatin condensation and fragmentation by confocal microscopy. All these findings reflect apoptosis of myocytes. The percentage of myocytes labeled with BCL2 (which protects cells against apoptosis) was 1.8 times as high in the hearts of patients with cardiac failure as in the normal hearts, whereas labeling with BAX (which promotes apoptosis) remained constant. The near doubling of the expression of BCL2 in the cardiac tissue of patients with heart failure was confirmed by Western blotting. CONCLUSIONS: Programmed death of myocytes occurs in the decompensated human heart in spite of the enhanced expression of BCL2; this phenomenon may contribute to the progression of cardiac dysfunction. 相似文献
78.
79.
JC Mohle-Boetani JE Koehler TG Berger PE LeBoit CA Kemper AL Reingold BD Plikaytis JD Wenger JW Tappero 《Canadian Metallurgical Quarterly》1996,22(5):794-800
Clinical characteristics associated with bacillary angiomatosis and bacillary peliosis (BAP) in patients with human immunodeficiency virus (HIV) infection were evaluated in a case-control study; 42 case-patients and 84 controls were matched by clinical care institution. Case-patients presented with fever (temperature, > 37.8 degrees C; 93%), a median CD4 lymphocyte count of 21/mm3, cutaneous or subcutaneous vascular lesions (55%), lymphadenopathy (21%), and/or abdominal symptoms (24%). Many case-patients experienced long delays between medical evaluation and diagnosis of BAP (median, 4 weeks; range, 1 day to 24 months). Case-patients were more likely than controls to have fever, lymphadenopathy, hepatomegaly, splenomegaly, a low CD4 lymphocyte count, anemia, or an elevated serum level of alkaline phosphatase (AP) (P < .001). In multivariate analysis, a CD4 lymphocyte count of < 200/mm3 (matched odds ratio [OR], 9.9; P < .09), anemia reflected by a hematocrit value of < 0.36 (OR, 19.7; P < .04), and an elevated AP level of > or = 2.6 mukat/L (OR, 23.9; P < .05) remained associated with disease after therapy with zidovudine was controlled for. BAP should be considered an AIDS-defining opportunistic infection and should be included in the differential diagnosis for febrile, HIV-infected patients with cutaneous or osteolytic lesions, lymphadenopathy, abdominal symptoms, anemia, or an elevated serum level of AP. 相似文献
80.