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排序方式: 共有1152条查询结果,搜索用时 15 毫秒
1.
A cost comparison of balloon angioplasty and stenting versus endarterectomy for the treatment of carotid artery stenosis 总被引:1,自引:0,他引:1
WD Jordan GD Roye WS Fisher D Redden HA McDowell 《Canadian Metallurgical Quarterly》1998,27(1):16-22; discussion 22-4
PURPOSE: Percutaneous transluminal angioplasty with stenting (PTAS) of the carotid artery has been advocated as an alternative treatment for high-grade stenosis. Rationale for this approach includes less morbidity, shorter recovery, and lower cost when compared with carotid endarterectomy (CEA). METHODS: The clinical results and hospital charges of patients who underwent elective treatment for carotid stenosis were reviewed. During a concurrent 14-month period, 218 patients were admitted 229 times for 234 procedures for the treatment of 239 carotid bifurcation stenoses, 109 by PTAS and 130 by CEA. Hospital charges were reviewed for each hospitalization and were categorized according to radiology, operating room, cardiac catheterization laboratory, and all other hospital charges. RESULTS: The combined incidence of postprocedure strokes and deaths were: PTAS, eight strokes (7.7%) and one death (0.9%); CEA, two strokes (1.5%) and two deaths (1.5%). Total hospital charges per admission for the two groups were $30,140 for PTAS and $21,670 for CEA. The average postprocedure length of stay for PTAS was 2.9 days (median, 2 days) and for CEA was 3.1 days (median, 3 days). Cardiac catheterization laboratory charges for the PTAS group were $12,968, whereas the operating room charges for the CEA group were $4263. When hospitalizations that were extended by complications were excluded, the average total charges for the PTAS group (n = 84) dropped to $24,848 (mean length of stay, 1.9 days) and for the CEA group (n = 111) to $19,247 (mean length of stay, 2.6 days). CONCLUSIONS: After evaluating hospital charges, PTAS for the treatment of carotid stenosis cannot currently be justified on the basis of reduced costs alone. With future cost-containing measures, total hospital charges can be reduced in both groups. 相似文献
2.
Many strains of laboratory mouse are uniquely susceptible to the development of T cell lymphoma/leukemia, either spontaneously or as a result of chemical or radiation exposure. In contrast, T cell leukemias or lymphomas which are relatively uncommon in human populations, are not easily induced by radiation, and are not generally associated with chemotherapy or chemical exposure. Evidence is presented to suggest that differences in the susceptibility to the development of these malignancies is related to subtle but important variations in the regulation of hematopoietic stem cell differentiation between these two species. 相似文献
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LM Sayre RT Naismith MA Bada WS Li ME Klein MD Tennant 《Canadian Metallurgical Quarterly》1996,1296(2):250-256
Horseradish peroxidase (HRP) is well known for mediating the electron-transfer oxidation of electron-rich aromatic 'donors' such as phenols and anilines, but has not been described to oxidize aliphatic amines. We here confirm the inability of HRP to oxidize typical aliphatic amines, even those which would exist significantly as free bases at the operative pH. In contrast, trans-2-phenylcyclopropylamine (2-PCPA) is both a substrate (turnover product is cinnamaldehyde) and a time-dependent inactivator of HRP. These activities of 2-PCPA are consistent with either a concerted or rapid sequential one-electron-oxidation/ring-opening to give an intermediate capable of covalent binding to the enzyme. 2-PCPA is the first known example of a simple aliphatic amine which serves as a substrate for HRP under turnover conditions. 相似文献
5.
MZ Kounnas EB Loukinova S Stefansson JA Harmony BH Brewer DK Strickland WS Argraves 《Canadian Metallurgical Quarterly》1995,270(22):13070-13075
Glycoprotein 330 (gp330) is a member of a family of endocytic receptors related to the low density lipoprotein receptor. gp330 has previously been shown to bind a number of ligands in common with its family member, the low density lipoprotein receptor-related protein (LRP). To identify ligands specific for gp330 and relevant to its localization on epithelia such as in the mammary gland, gp330-Sepharose affinity chromatography was performed. As a result, a 70-kDa protein was selected from human milk and identified by protein sequencing to be apolipoprotein J/clusterin (apoJ). Solid-phase binding assays confirmed that gp330 bound to apoJ with high affinity (Kd = 14.2 nM). Similarly, gp330 bound to apoJ transferred to nitrocellulose after SDS-polyacrylamide gel electrophoresis. LRP, however, showed no binding to apoJ in either type of assay. The binding of gp330 to apoJ could be competitively inhibited with excess apoJ as well as with the gp330 ligands apolipoprotein E, lipoprotein lipase, and the receptor-associated protein, a 39-kDa protein that acts to antagonize binding of all known ligands for gp330 and LRP. Several cultured cell lines that express gp330 and ones that do not express the receptor were examined for their ability to bind and internalize 125I-apoJ. Only cells that expressed gp330 endocytosed and degraded radiolabeled apoJ. Furthermore, F9 cells treated with retinoic acid and dibutyryl cyclic AMP to increase expression levels of gp330 displayed an increased capacity to internalize and degrade apoJ. Cellular internalization and degradation of radiolabeled apoJ could be inhibited with unlabeled apoJ, receptor-associated protein, and gp330 antibodies. The results indicate that gp330 but not LRP can bind to apoJ in vitro and that gp330 expressed by cells can mediate apoJ endocytosis leading to lysosomal degradation. 相似文献
6.
In this note, simple symmetric interval bounds on the singular values of a matrix based on its Gershgorin disks are proposed. This allows the Gershgorin theorem to be used not only to provide information about the location of the eigenvalues of a matrix but also its singular values. This is utilized for the proposition of a new design technique for singular value loop shaping based on the diagonal dominance methodology for design of linear multivariable plants. In return, this allows multiple-channel simply structured controllers to be designed with a view to robustness and to meet constraints and specifications on the behavior of its singular values. A design example is given demonstrating the effectiveness of this approach. 相似文献
7.
WS McDougal 《Canadian Metallurgical Quarterly》1997,157(4):1335-1336
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WS Ahn J Yoo SW Huh CK Kim JM Lee SE Namkoong SM Bae IP Lee 《Canadian Metallurgical Quarterly》2003,12(5):383-390
We investigated clinical efficacy of green tea extracts (polyphenon E; poly E and (-)-epigallocatechin-3-gallate [EGCG]) delivered in a form of ointment or capsule in patients with human papilloma virus (HPV) infected cervical lesions. Fifty-one patients with cervical lesions (chronic cervicitis, mild dysplasia, moderate dysplasia and severe dysplasia) were divided into four groups, as compared with 39 untreated patients as a control. Poly E ointment was applied locally to 27 patients twice a week. For oral delivery, a 200 mg of poly E or EGCG capsule was taken orally every day for eight to 12 weeks. In the study, 20 out of 27 patients (74%) under poly E ointment therapy showed a response. Six out of eight patients under poly E ointment plus poly E capsule therapy (75%) showed a response, and three out of six patients (50%) under poly E capsule therapy showed a response. Six out of 10 patients (60%) under EGCG capsule therapy showed a response. Overall, a 69% response rate (35/51) was noted for treatment with green tea extracts, as compared with a 10% response rate (4/39) in untreated controls (P<0.05). Thus, the data collected here demonstrated that green tea extracts in a form of ointment and capsule are effective for treating cervical lesions, suggesting that green tea extracts can be a potential therapy regimen for patients with HPV infected cervical lesions. 相似文献
10.
1. Occupational health nurses need a general knowledge of psychiatric medications to work effectively with clients and their off site health providers. 2. Acquiring an understanding of the major classes of medications--anti-psychotic, anti-anxiety, anti-depressant, and antimanic--is important. 3. It is helpful to understand under what conditions and with which conditions psychotropic medications are helpful. 相似文献