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961.
LA Primeau 《Canadian Metallurgical Quarterly》1996,50(7):569-577
The contribution of a balance of work and leisure to health and a sense of well-being is a common sense assumption in everyday knowledge as well as in occupational therapy. The impact of the organization and balance of occupations in daily life on health, adaptation, life satisfaction, and a sense of well-being are central issues in occupational science. One of occupational science's potential contributions to society is the ability to provide understanding and insights that transcend common sense assumptions and everyday knowledge about occupations. This article will address, through a review of the literature, some of the limitations inherent in beliefs about a healthy balance of work and leisure. It will demonstrate how distinctions between work and leisure are culturally bound and perpetuate the assumption that they are dichotomous experiences. This dichotomy is shown to be a false one and must be transcended in order to explore the question of what is a healthy balance within daily life. This article concludes with considerations for occupational therapy research and practice that may arise from transcendence of the dichotomy of work and leisure. 相似文献
962.
963.
As the number of obese people in the United States continues to increase, all nurses will encounter the unique challenges that result from the pathophysiological changes in this population. The combination of morbid obesity and spinal cord injury creates complex medical management for caregivers throughout hospitalization and after dismissal. Thus, the complications of spinal cord injury are intensified with obesity. Prevention and treatment of secondary complications require nursing practice to go above and beyond the standards of care. This article reviews complications and adjustments in the care of the morbidly obese spinal cord-injured patient, beginning at the scene of injury and through the emergency trauma, intensive care, and rehabilitation units. 相似文献
964.
S-2150 is a new 1,5-benzothiazepine derivative that inhibits [3H]diltiazem and [3H]WB4101 bindings to the membrane of rat tissue. The effects of S-2150 on ischemia/ reperfusion injury were studied in anesthetized rats. S-2150 reduced the myocardial infarct size (IS) induced by 20-min coronary artery occlusion followed by reperfusion. To evaluate reperfusion-induced ventricular tachycardia and fibrillation (VT, VF), we occluded the coronary artery for 4 min and then reperfused it. The incidence of arrhythmia was blocked by S-2150, and this effect offered protection against cardiac death. Prazosin did not modify the IS or incidence of reperfusion arrhythmias, but combined treatment with a noneffective dose of diltiazem showed significant cardioprotective effects. We also compared the direct effects of S-2150 and diltiazem on cardiac function and coronary perfusion flow using isolated rat hearts. Both drugs decreased mechanical function and increased coronary flow, with S-2150 being less cardiodepressive and more vasodilatory. S-2150 is cardioprotective at doses comparable to hypotensive doses even though its cardiodepressant effect is much weaker than that of diltiazem. This effectiveness may be partly explained by its dual characteristics: blocking the Ca channel and the alpha 1-adrenoceptor. 相似文献
965.
HN Rosen LA Maitland JW Suttie WJ Manning RJ Glynn SL Greenspan 《Canadian Metallurgical Quarterly》1993,94(1):62-68
One important mechanical property of core composite resins is fracture toughness, KIC, which expresses serviceability in the oral cavity, such as the resistance to marginal fracture. KIC values of eight commercial core composite resins were examined by the single-edge notched-beam (S.E.N.B.) method. Two composites containing about 80 wt% Si3N4 fillers exhibited both the highest KIC value of around 2.0 MN.m-3/2 and the highest hardness value. The other six composites containing 66 to 86 wt% SiO2-based fillers had KIC values of around 1.2 to 2.0 MN.m-3/2, and there was a tendency toward higher KIC values as hardness increased. It was speculated that the clinical acceptability of core composite resins could be broadened, if dental clinicians selected composites with higher KIC values. 相似文献
966.
967.
BA Kwiatkowski AG Zielińska-Kwiatkowska A Migdalski LA Kleczkowski LD Wasilewska 《Canadian Metallurgical Quarterly》1995,165(2):219-222
The U-turn (uridine turn) is an RNA structural motif that contains a change in backbone direction stabilized by specific interactions across the bend. It was first identified in the anticodon loop and the T-loop of yeast tRNA(Phe) (Quigley & Rich, 1976, Science 194:796-806) and has recently also been found in the crystal structure of the hammerhead ribozyme (Pley HW, Flaherty KM, McKay DB, 1994a, Nature 372:68-74). These U-turn motifs follow a UNR consensus sequence (where N is any nucleotide and R is G or A). Here we report that the frequently occurring GNRA tetraloops also contain a U-turn motif, and we discuss the role of U-turns as abundant tertiary structural motifs in RNA. 相似文献
968.
PURPOSE: The purpose of this study was to explore the feasibility of iliofemoral endarterectomy performed through a single groin incision. METHODS: Thirty-two patients aged 34 to 75 years (mean age 63.4 years) with a male/female ratio of 20:12 underwent 36 lower extremity inflow reconstructions from July 1989 to September 1994. Surgical indications were for limb-threatening ischemia in 24 patients and for claudication in eight patients. The procedures were done for occlusive disease of the external iliac artery and common femoral artery with patients under either spinal (n = 24) or local (n = 12) anesthesia. Intraoperative balloon angioplasty with fluoroscopic guidance preceded open retrograde iliofemoral endarterectomy. Adjunctive procedures included 18 profundaplasties, eight femorofemoral, nine femoropopliteal, and one femorotibial bypasses. RESULTS: Thirty-three of the 36 cases were initially successful. The three failures were in patients with extensive calcification. The mean follow-up has been 36.4 months, and the patency rate was 80.5% at 3 and 4 years. The four failures noted on follow-up were caused by three common iliac artery stenoses and one iliac system occlusion. The former group was successfully treated with balloon angioplasty/stent, and the latter patient required an aortofemoral bypass. No operative deaths or limb loss occurred in this series. CONCLUSIONS: Retrograde iliofemoral endarterectomy facilitated by balloon angioplasty is a safe, easy-to-perform, and viable option for patients with combined external iliac artery and common femoral artery occlusive disease. Midterm results (36.4 months) are favorable, and most hemodynamic failures are easy to correct with standard endovascular techniques. 相似文献
969.
VR Southgate LA Tchuem Tchuenté J Vercruysse J Jourdane 《Canadian Metallurgical Quarterly》1995,81(8):651-656
In mixed infections of Schistosoma haematobium and S. mattheei, homospecific and heterospecific pairs are formed, with a preponderance of homospecific pairs indicating the existence of a mate preference system. S. haematobium apparently exhibits a greater specific mate recognition system than does S. mattheei. In sequential infections when mice are exposed to S. mattheei 4 weeks after infection with S. haematobium, S. haematobium males are better at pairing with S. mattheei females than are S. mattheei males. Hence, genetic exchanges between S. haematobium and S. mattheei giving rise to viable hybrids poses the problem of the genetic identity of these species of schistosomes. The most important reproductive isolating mechanisms are definitive host specificity, S. haematobium being primarily a parasite of man, whereas S. mattheei is a parasite of domestic stock and wild ungulates, and the preference for homospecific pairings in simultaneous infections. In contrast, when S. haematobium is the older infection, S. haematobium males are better than S. mattheei males at pairing with females of either species. Hybridisation is the likely outcome of such interactions. The lack of viability of S. mattheei male X S. haematobium female indicates genetic differences between the two species. Occurrences of natural hybridisation between S. haematobium and S. mattheei may lead to a change in the response of the parasite to chemotherapeutic treatment. 相似文献
970.
OBJECTIVE: Coincident with a change in the physician staff in our pediatric intensive care unit (PICU), the frequency and duration of invasive monitoring were decreased. We examined the impact of this change on outcomes, complications, and hospital charges in infants admitted to the PICU with respiratory syncytial virus (RSV) infection. STUDY DESIGN: We reviewed medical records of all children less than 1 year of age who were admitted to the PICU from January 1989 to July 1993 with confirmed RSV infection. Patient characteristics, therapeutic interventions, outcomes, and hospital charges were extracted and compared. RESULTS: Seventy-eight patients were identified, 38 admitted from January 1989 through July 1991 (group 1) and 40 from July 1991 through July 1993 (group 2). The groups were well matched in age, preexisting disease, and cardiorespiratory status on admission. Group 1 had significantly greater use of invasive monitoring, pharmacologic paralysis, inotropes, blood products, antibiotics, and parenteral nutrition. Outcomes were not different, but group 1 patients had significantly longer stays, more complications, and higher hospital charges. CONCLUSIONS: Routine use of invasive monitoring of PICU patients with RSV disease was associated with increased laboratory testing, overtreatment, and significant increases in costs and morbidity without improvement in outcome. 相似文献