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991.
本文讨论了 Fuzzy 对称可实现矩阵的容度问题。找出了可计算的一个下界估计,借助于文〔8〕和文〔9〕提出的Ⅱ型 Fuzzy 关系不定方程的求解,给出了计算容度和计算相应的一组实现矩阵的算法。 相似文献
992.
To investigate the neurotoxicity of acetaldehyde covalent adducts, immunohistochemical staining for acetaldehyde adducts using the antibody against acetaldehyde adducts, was performed in the cerebral cortex of ethanol-fed (withdrawal) mice. In the ethanol-fed mice, the degeneration in the cerebral cortex was found, while the protein epitope related to acetaldehyde was found in the cerebral cortex, liver and adrenal cortex. No histochemical and immunohistochemical changes in the tissues from the control mice were found. It is possible that acetaldehyde adducts may effect on the cerebral cortex as the neurotoxicity which cause psychosis such as delirium and hallucination after alcohol drinking. 相似文献
993.
994.
本文介绍了光突发交换的基本概念,JET协议下光突发交换,以及对核心节点、边缘节点的初步介绍。从文中可以看到JET协议下的光突发交换特点,核心节点、边缘节点在光突发交换中的作用。而标签突发包交换是一种基于光突发交换的新技术,本文将对此新技术进行讨论。 相似文献
995.
J Pe?a-Casanova M Aguilar I Bertran-Serra P Santacruz G Hernández R Insa A Pujol JM Sol R Blesa 《Canadian Metallurgical Quarterly》1997,12(2):61-68
We give an account of the first Austrian clinical results of a prospective study dealing with fractures of the femoral shaft treated with the UFN-system, the intraoperative handling especially considering the intra- and postoperative complications. The UFN-system combines the advantages of numerous proximal interlocking options for the treatment of nearly all femoral fracture patterns with that of the unreamed nailing (biological osteosynthesis, primary stability with individual after-treatment, high patient's comfort and early mobilisation). Within two years (VII/94-VII/96) sixty closed and four second degree open fractures were stabilized with the unreamed femoral nail. In twelve cases we used the spiral blade interlocking technique. Five times we changed from external fixator to the UFN. The fractures were classified according to the AO-classification. In 64 implanted UFN there occurred twelve intraoperative and four postoperative complications. In five cases reoperation was necessary. Failings in the operative technique, numerous different experienced surgeons and a deficient after_treatment led to our pitfalls. 相似文献
996.
TD de Gruijl HJ Bontkes JM Walboomers JT Schiller MJ Stukart BS Groot MM Chabaud AJ Remmink RH Verheijen TJ Helmerhorst CJ Meijer RJ Scheper 《Canadian Metallurgical Quarterly》1997,89(9):630-638
BACKGROUND: Infection with cancer-linked human papillomavirus (HPV) types such as HPV type 16 (HPV16) is the most important risk factor in the development of cervical cancer. It has been shown that immunoglobulin G (IgG) antibody responses against HPV16 virus-like particles (VLPs) are specifically associated with genital HPV16 infection. PURPOSE: The aim of this study was to determine the temporal relationships between the presence of HPV16 VLP-specific IgGs, HPV16 infection patterns, and the course of premalignant cervical disease. METHODS: Plasma samples from 133 women who had been diagnosed originally with mild to moderate cervical dyskaryosis and enrolled in a prospective non-intervention cohort study conducted in Amsterdam, The Netherlands, from 1991 through 1996 were analyzed for the presence of HPV16 VLP-specific IgGs by use of an enzyme-linked immunosorbent assay. A detailed analysis was performed on 43 women with different HPV16 infection patterns during a follow-up period of 10-34 months. Progression or regression of cervical intraepithelial neoplasia (CIN) lesions was monitored by cytologic and colposcopic testing at intervals of 3-4 months. HPV typing in cervical smears was performed by use of a polymerase chain reaction-based assay. Statistical analysis of the serologic data was performed by use of the Mann-Whitney U test or 2 x 2 table analyses. RESULTS: The presence of HPV16 VLP-specific IgGs in the plasma of the patients was found to be associated with the presence of HPV16 DNA in the cervical smear. Significantly higher proportions of patients with persistent HPV16 infections (i.e., who were polymerase chain reaction positive in three to 11 consecutive tests) than of patients with cleared HPV16 infections were found to be positive for the presence of HPV16 VLP-specific IgGs (18 [69.2%] of 26 versus nine [28.1%] of 32, respectively; P = .003). HPV16 VLP-specific IgGs were consistently detected in all women (n = 11) who were persistently HPV16 DNA positive during follow-up and whose disease ultimately progressed to CIN III (histologically diagnosed severe dysplasia or carcinoma in situ). CONCLUSION: HPV16 VLP-specific IgG responses are present in the plasma of a majority of patients with persistent HPV16 infections and histologically confirmed high-grade lesions but only in a smaller subset of patients with cleared HPV16 infections and either normal cervical histology or low-grade CIN lesions. IMPLICATIONS: These results suggest that HPV16 VLP-specific antibodies are not responsible for the clearance of virally induced CIN lesions but that they might, in patients with persistent HPV16 infections, be indicative of an increased cervical cancer risk. 相似文献
997.
998.
PURPOSE: To evaluate prospectively the use of peripherally inserted central catheters in a large pediatric population. MATERIALS AND METHODS: During a 3-year period, data were collected prospectively on 523 consecutive attempts to place peripherally inserted central catheters in children. Patients underwent radiologically guided placement because attempts were unsuccessful on the inpatient units or a patient request was made. Fluoroscopy with use of contrast material and venography were used to place catheters and document the position of the catheter tip. Follow-up data were collected until treatment cessation or catheter removal. RESULTS: Among 523 attempts, 486 (92.9%) catheters were successfully placed. In the 37 (7.1%) unsuccessful cases, more than half of these children were younger than 24 months of age or weighed less than 5 kg. Ages of patients in whom 523 placement attempts were made ranged from 3 weeks to 18 years (mean, 6.9 years). Catheters were in place from 1 to 390 days (mean, 20 days). Frequency of infection was 1.9% (nine cases); incidence of infection was 0.93 per 1,000 catheter-placement days. There were two cases (0.4%) of central venous thrombosis. Most patients were discharged within 2 days of catheter placement. CONCLUSION: Fluoroscopically guided placement of peripherally inserted central catheters is a safe and effective method for establishing intermediate- and long-term central venous access in the pediatric population. 相似文献
999.
1000.