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排序方式: 共有1112条查询结果,搜索用时 15 毫秒
41.
42.
Genee Brukwitzki MSN RN Cynthia Holmgren MSN RN OCN Regina Marie Maibusch MS RN CS 《International journal of nursing terminologies and classifications》1996,7(2):63-69
The investigators designed this validation study to determine the defining characteristics of the nursing diagnosis ineffective airway clearance. Using Fehring's Diagnostic Content Validity Model, 546 nurses who care for respiratory clients validated one major and 19 minor defining characteristics. Nine characteristics previously described in the literature were eliminated. Clarification of the defining characteristics of this diagnosis improves communication in practice, education and research. 相似文献
43.
Linda Funk Barloon MS RN CS Psychiatric Clinical Nurse Specialist 《Journal of child and adolescent psychiatric nursing》1997,10(4):43-44
Performance Breakthroughs for Adolescents With Learning Disabilities or ADD. G. Markel & J. Greenbaum. 相似文献
44.
Characterization of the effects of cultured vascular cells on the activation of blood coagulation 总被引:9,自引:0,他引:9
The coagulant properties of intact bovine vascular cells (aortic endothelial and smooth muscle cells) and human vascular cells (cutaneous and foreskin microvascular cells, umbilical venous endothelium) grown in vitro were studied. Compared to nonvascular cells (fibroblasts, corneal endothelial cells, fetal lung or intestinal mucosal cells), vascular cells had little procoagulant activity. Radioimmunologic measurement of thrombin in recalcified plasma demonstrated markedly lower concentrations of thrombin in the presence of vascular endothelial and smooth muscle cells compared to corneal endothelial and fetal lung cells. The low thrombin concentrations were not a consequence of thrombin binding to the vascular cells nor were they due to accelerated thrombin inactivation by antithrombin-III or alpha 2-macroglobulin. Neither vascular cells nor the nonvascular cells promoted contact activation of plasma as measured by a sensitive specific assay for kallikrein. Studies with intact cell monolayers and purified factors VIIa and X indicated that while nonvascular cells express tissue factor activity, vascular cells do not exhibit this property. These data suggest that the nonthrombogenic nature of intact vascular cells is due to their failure to initiate contact activation and to express tissue factor activity. In addition, the primary difference in coagulant potential between vascular cells and nonvascular cells is the lack of tissue factor expression by the vascular cells. 相似文献
45.
46.
August CS; King E; Githens JH; McIntosh K; Humbert JR; Greensheer A; Johnson RB 《Blood》1976,48(4):491-498
Marrow transplantation was attempted in a 13-yr-old boy with congenital hypoplastic anemia who had never responded to corticosteroid therapy. Prior to the transplant, he had received 238 transfusions, at least 12 of which were from his father. He was prepared for grafting with antilymphocyte globulin, procarbazine, and total body irradiation (1000 rads). The patient, whose red cells were Group B, then received marrow cells from his Group O, histocompatible, sister. Thereafter, reticulocytes, Group O erythrocytes, and female leukocytes appeared in the peripheral blood. Erythroid precursors were seen in the patient's marrow for the first time in his life, and all lacked fluorescent Y chromosomes. Dividing cells were all female. After initially progressing well, the patient developed interstitial pneumonia and died 55 days after the transplant. The successful erythroid graft suggested that this patient's failure to produce red blood cells was due to a defective stem cell rather than to a humoral defect, plasma inhibitor, or abnormal marrow microenvironment. It suggested further that sibling marrow may be engrafted in patients who have received multiple transfusions, even from a parent. 相似文献
47.
Crist WM; Shuster JJ; Falletta J; Pullen DJ; Berard CW; Vietti TJ; Alvarado CS; Roper MA; Prasthofer E; Grossi CE 《Blood》1988,72(6):1891-1897
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment. 相似文献
48.
OBJECTIVE: To study the predictive factors for avascular necrosis (AVN) of
bone in patients with systemic lupus erythematosus (SLE). METHOD: The
records of 38 SLE patients who developed clinically apparent AVN during the
course of their disease were reviewed. Information on clinical
presentation, corticosteroid usage and autoantibody profiles was obtained,
and comparison was made between these patients and 143 consecutive control
SLE patients who did not have AVN. RESULTS: The point prevalence of AVN in
our SLE population was 12%. Patients with AVN, when compared with controls,
had a significantly higher incidence of neurological disease (39% vs 14%; P
< 0.001) and Cushingoid body habitus after steroid treatment (79% vs
53%; P = 0.004). The highest cumulative prednisolone dose in 1 and 4 months
was significantly higher in the AVN group than the controls (1.8 vs 1.1 and
4.5 vs 2.8 g, respectively; P < 0.01 in both) and showed a linear trend
with the incidence of AVN (chi2 test for trend, P < 0.01 in both). Lupus
anticoagulant was associated with AVN (P = 0.02, odds ratio 2.88 [1.14-
7.28]). Logistic regression analysis revealed that the highest cumulative
prednisolone dose administered in 4 months, the maximum and mean daily
prednisolone dosage, and the lupus anticoagulant were independent risk
factors for AVN. CONCLUSIONS: Corticosteroid remains the major predisposing
factor for AVN in SLE. Patients who require an initial high-dose steroid
for disease control are at risk of AVN, especially if they are positive for
the lupus anticoagulant or develop Cushingoid habitus after steroid
treatment. High-risk patients should be closely monitored so that early AVN
can be diagnosed by sensitive techniques such as magnetic resonance imaging
and radioisotope bone scanning.
相似文献
49.
delta-Aminolevulinate dehydratase in human erythroleukemia cells: an immunologically distinct enzyme 总被引:4,自引:0,他引:4
Physicochemical and immunologic properties of delta-aminolevulinate (ALA) dehydratase in human K562 erythroleukemia cells were examined. ALA dehydratase activity was found to increase in K562 cells after treatment with butyric acid or selenium oxide. Enzyme activity in untreated K562 cells was comparable to that in normal adult erythrocytes but was increased three- to six-fold in K562 cells treated with 1.2 mmol/L butyric acid or 0.03 mmol/L selenium oxide. The Michaelis-Menten constant (Km), the inhibitor constant (Ki), and elution profile by diethylaminoethyl (DEAE) cellulose chromatography were similar for ALA dehydratase from K562 cells and normal human adult and human fetal erythrocytes. However, ALA dehydratase from K562 cells did not react with a monospecific rabbit antibody against ALA dehydratase purified from normal adult erythrocytes, although the antibody reacted with the enzyme from normal adult and fetal red cells. These findings indicate that ALA dehydratase in K562 cells is immunologically distinct from the normal enzyme. 相似文献
50.