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81.
82.
The documentation of critical care nurses' competence is essential so that required standards are met. The authors set criteria against which a competency documentation system can be evaluated. 相似文献
83.
B Dahlén P M O'Byrne R M Watson A Roquet F Larsen M D Inman 《The European respiratory journal》2001,17(4):581-588
Dry air exercise challenges are frequently used to screen medications that have potential utility in the management of exercise-induced bronchoconstriction (EIB). The purpose of this study was to determine the reproducibility of three outcome measurements made using such challenges, and sample size requirements for drug evaluation studies based on these outcomes. Forty adult subjects with asthma, who tested positively on a screening exercise challenge, were subjected to two further identical challenges, separated by 1 to >35 days. Outcome measurements included the maximum per cent fall in forced expiratory volume in one second (FEV1), after exercise (% fallmax), and the area under the per cent fall in FEV1/time curve for 30 min (AUC30) and 60 min (AUC60) after exercise. The reproducibility of these outcomes, as assessed by intraclass correlation coefficients was 0.72, 0.53 and 0.35 for % fallmax, AUC30 and AUC60 measurements, respectively. The sample size requirements to demonstrate an attenuation of EIB equivalent to a 50% reduction in % fallmax was 9, 14 and 19 subjects for the % fallmax, AUC30 and AUC60 responses, respectively (90% power). It is concluded that the maximum percentage fall in forced expiratory volume in one second has greater reproducibility and results in greater power in clinical trials than area under the curve measurements. Sample size calculation curves are provided which may be used in study design and interpretation of published studies. 相似文献
84.
Transient synovitis of the hip in children: role of US 总被引:7,自引:0,他引:7
Marchal GJ; Van Holsbeeck MT; Raes M; Favril AA; Verbeken EE; Casteels- Vandaele M; Baert AL; Lauweryns JM 《Radiology》1987,162(3):825-828
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies. 相似文献
85.
86.
This study was designed to assess the postnatal maturation of adrenocorticotropin (ACTH) levels in piglets under basal conditions and in response to single, acute stressors. ACTH levels were measured by radioimmunoassay in plasma, cerebrospinal fluid (CSF) and in a dorsal medullary slice containing the nucleus tractus solitarii (dmscNTS) of young and older piglets (1.5-6 and 35-43 days old, respectively) under the following experimental conditions: (1) normoxia (both groups); (2) hypoxia, 10% O2/N2 for greater than or equal to 30 min (both groups); (3) sham anesthesia, i.p. saline in normoxia (young group); (4) anesthesia, 25 mg/kg i.p. pentobarbital in normoxia (young group), and (5) anesthesia combined with hypoxia (young group). During normoxia, ACTH levels in young, as compared to older piglets, were higher in CSF (p less than 0.01) and plasma (0.05 less than p less than 0.10) and not different in dmscNTS. Hypoxia produced no ACTH changes in CSF, increased ACTH in plasma of young (p = 0.03) and older piglets (p = 0.09), and decreased ACTH in dmscNTS of older (p = 0.01) and young piglets (p = 0.07). As compared to sham anesthesia, anesthesia did not alter any ACTH levels. Combined hypoxia and anesthesia increased ACTH levels in plasma when compared to normoxia (p less than 0.05), sham anesthesia (p less than 0.05) or anesthesia alone (p less than 0.05), but not when compared to hypoxia alone. We conclude that neonatal swine have high basal ACTH levels and mount significant plasma ACTH responses to a single, acute hypoxic stressor. The presence of ACTH in the region of the NTS supports its possible role as a neuromodulator in the brain. 相似文献
87.
GJ Levy ; G Selset ; D McQuiston ; SJ Nance ; G Garratty ; LE Smith ; D Goldfinger 《Transfusion》1988,28(3):265-267
Several published reports have documented the variable survival of Yt(a+) red cells (RBC) in patients with anti-Yt(a) as measured by 51Chromium (Cr)-labeled RBC survival studies. Similar studies with anti-Yt(b) have not been reported. A 51Cr-labeled RBC survival study was performed using Yt(b+) RBCs and a monocyte monolayer assay in a young hemodialysis patient who required chronic transfusion therapy and who had developed anti-Yt(b). The survival of the transfused RBCs was 100 and 93 percent at 1 and 24 hours, respectively, with a half life of 21 days at termination of the study (normal, 28 to 32 days). These results showed no evidence of rapid destruction of the Yt(b+) RBCs, indicating that this patient could be transfused safely with blood from Yt(b+) donors. Long-term survival of the 51Cr-labeled Yt(b+) RBCs was shortened moderately, however, a finding that correlated with a slightly abnormal monocyte monolayer assay test. 相似文献
88.
Binding of immunoglobulin G aggregates and immune complexes in human sera to Staphylococci containing protein A. 下载免费PDF全文
J S McDougal P B Redecha R D Inman C L Christian 《The Journal of clinical investigation》1979,63(4):627-636
Using the Cowan I strain of Staphylococcus aureus, we compared the binding properties of human monomeric immunoglobulin (Ig)G and oligomeric or complexed IgG. Heat-aggregated IgG served as a model for complexed IgG and heat-killed, formalin-fixed S. aureus (StaphA) as a cellular receptor for IgG, in determining the parameters for oligomeric and monomeric binding. Because of its capacity for multipoint attachment, complexed IgG binding was favored over monomeric IgG binding, and this preferential binding was demonstrated kinetically in equivalent forward rates of binding but in a much slower rate of release from StaphA receptors. From binding studies, we determined which conditions maximize complexes IgG binding and minimized monomeric IgG binding and applied them to the development of an assay for aggregated IgG and immune complexes in human sera. The StaphA binding assay that was devised is quantitative, sensitive, and not complement dependent. It is relatively unaffected by factors such as heparin, complement fixation, native antibodies, and immunoglobulin concentrations, but is affected by the presence of rheumatoid factors. It compares favorably with two other complement-dependent assays of immune complexes, the 125I-Clq binding assay and the Raji cell assay, in terms of sensitivity and the size of immune complexes detected. Studies on the potential of the assay for detecting, isolating, and characterizing immune complexes in biological fluids are presented. 相似文献
89.
Anti-allergic therapies: effects on eosinophil progenitors 总被引:3,自引:0,他引:3
Baatjes AJ Sehmi R Saito H Cyr MM Dorman SC Inman MD O'Byrne PM Denburg JA 《Pharmacology & therapeutics》2002,95(1):63-72
Marked eosinophilic infiltration is the typical inflammatory response associated with allergic inflammation. Previous research involving animal and human models has established a role for the eosinophil/basophil hematopoietic progenitor in a systemic process of allergic inflammation. In this article, we will review the evidence implicating eosinophil/basophil progenitors in this systemic response and will discuss the rationale for targeting this cell in the treatment of allergic disease. In this context, we discuss corticosteroid treatment of allergic diseases, such as asthma and its effects on hematopoietic mechanisms, the effects of therapies that inhibit the actions of cysteinyl leukotrienes, the effects of in vivo blockade of the eosinophil-active cytokine interleukin-5, and the effects of antihistamines on hematopoiesis. It is suggested that several anti-allergic therapies exert their beneficial effects on allergic inflammation by influencing eosinophil production systemically. Therefore, targeting the systemic hematopoietic response may provide additional, more beneficial, therapeutic effects. 相似文献
90.
两种麻醉方法对单双肺通气期间能量代谢和呼吸氧价及应激反应的影响 总被引:1,自引:0,他引:1
目的:观察胸段硬膜外复合全静脉麻醉和全静脉麻醉对单、双肺通气能量代谢、呼吸氧价和应激反应的影响,比较两者的差异。方法:选择2004-07/2005-01徐州医学院附属医院心胸外科择期行食管癌根治术且需要单肺通气的患者40例,按随机数字表法分为硬膜外复合全静脉麻醉组(n=20)和全静脉麻醉组(n=20),经患者同意并签字后进入试验。分别在单肺通气和双肺通气时进行氧耗量、二氧化碳排出量、能量代谢和呼吸商测定,同时测量肾上腺素、去甲肾上腺素、皮质醇和血糖水平。结果:40例患者全部进入结果分析,无脱落。①在单、双肺通气时硬膜外复合全静脉麻醉组的氧耗量、二氧化碳排出量、能量代谢均高于全静脉麻醉组(P<0.05);两组患者单肺通气时段氧耗量、二氧化碳排出量、能量代谢低于双肺通气时段,但差异无显著性意义(P>0.05)。②在单、双肺通气时硬膜外复合全静脉麻醉组的肾上腺素、去甲肾上腺素、皮质醇和血糖水平均低于全静脉麻醉组(P<0.05);单、双肺通气相比,两组患者肾上腺素、去甲肾上腺素变化差异无显著性意义(P>0.05)。结论:与全静脉麻醉相比,胸段硬膜外阻滞复合全静脉麻醉能够增加胸科手术的氧耗量、能量代谢,减轻应激反应。单、双肺通气期间没有明显差异。 相似文献