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991.
CD Spies M Kissner T Neumann S Blum C Voigt T Funk N Runkel F Pragst 《Canadian Metallurgical Quarterly》1998,33(6):661-669
Antibodies to DNA are believed to play an important role in systemic lupus erythematosus (SLE). High affinity IgG antibodies which show marked specificity for double stranded DNA (dsDNA) are particularly closely linked to the occurrence and severity of tissue damage. Sequence analysis of mouse and human monoclonal antibodies has previously suggested that mutations in the complementarity determining regions (CDRs) play a major role in determining these binding properties. In many cases such mutations increase the overall number of basic residues in the CDRs. To further elucidate the role played by such mutations it is important to develop methods of expressing cloned autoantibody cDNA in the form of functional whole immunoglobulin molecules. We describe a system in which autoantibody VH and VL cDNA from monoclonal human anti-DNA antibodies, B3 and WRI176 were cloned into separate vectors which allowed their expression as whole heavy and whole light chains respectively. By cotransfecting mammalian cells with pairs of heavy and light chain vectors it was possible to produce whole IgG molecules from each of the four possible VH/VL combinations. Only antibody produced by homologous VH and VL pairs bound DNA, suggesting that in these autoantibodies both chains are important in conferring this property. 相似文献
992.
The surgical technique of redraping of the inferior arc of the orbicularis oculi muscle is used primarily to produce lower lid and midfacial smoothing in patients undergoing aesthetic surgery. The midfacial fat compartments, suborbicularis oculi fat and malar fat, are bound to the orbicularis muscle by the superficial muscular aponeurotic system so that redraping the orbicularis muscle also repositions the midface. Orbicularis arc redraping should be accompanied by lateral canthoplasty to ensure stability to the shape of the eyelid fissure postoperatively. Modifications in orbicularis redraping and canthoplasty technique are necessary in patients with prominent eyes and distensible lower lids. Supraplacement of canthal fixation is needed in patients with prominent eyes, and lid shortening is needed in patients who have distensible lower lids. This technique also can be used in patients undergoing reconstructive surgery for correction of lower lid retraction because of its ability to recruit periorbital skin upward into the lower lid. For more severe cases of lower lid retraction after aesthetic surgery, adjunctive procedures such as spacer implants in the lower lid and periosteal flap canthoplasty can be used together with the orbicularis arc redraping to rehabilitate patients. 相似文献
993.
JJ Chu KD Chen YL Lin CY Fei AS Chiang CD Chiang YK Lai 《Canadian Metallurgical Quarterly》1998,68(4):472-483
Taxol, a microtubule stabilizing agent, has been extensively investigated for its antitumor activity. The cytotoxic effect of taxol is generally attributed to its antimicrotubule activity and is believed to be cell cycle dependent. Herein, we report that taxol induces hyperphosphorylation and reorganization of the vimentin intermediate filament in 9L rat brain tumor cells, in concentration- and time-dependent manner. Phosphorylation of vimentin was maximum at 10(-6) M of taxol treatment for 8 h and diminished at higher (10(-5) M) concentration. Enhanced phosphorylation of vimentin was detectable at 2 h treatment with 10(-6) M taxol and was maximum after 12 h of treatment. Taxol-induced phosphorylation of vimentin was largely abolished in cells pretreated with staurosporine and bisindolymaleimide but was unaffected by H-89, KT-5926, SB203580, genistein, and olomoucine. Thus, protein kinase C may be involved in this process. Hyperphosphorylation of vimentin was accompanied by rounding up of cells as revealed by scanning electron microscopy. Moreover, there was a concomitant reorganization of the vimentin intermediate filament in the taxol-treated cells, whereas the microtubules and the actin microfilaments were less affected. Taken together, our data demonstrate that taxol induces hyperphosphorylation of vimentin with concomitant reorganization of the vimentin intermediate filament and that this process may be mediated via a protein kinase C signaling pathway. 相似文献
994.
995.
X Xiao R Mukkamala N Sheynberg SM Grenon MD Ehrman TJ Mullen CD Ramsdell GH Williams RJ Cohen 《Canadian Metallurgical Quarterly》2004,96(2):489-497
Microgravity-induced orthostatic intolerance (OI) continues to be a primary concern for the human space program. To test the hypothesis that exposure to simulated microgravity significantly alters autonomic nervous control and, thus, contributes to increased incidence of OI, we employed the cardiovascular system identification (CSI) technique to evaluate quantitatively parasympathetic and sympathetic regulation of heart rate (HR). The CSI method analyzes second-to-second fluctuations in noninvasively measured HR, arterial blood pressure, and instantaneous lung volume. The coupling mechanisms between these signals are characterized by using a closed-loop model. Parameters reflecting parasympathetic and sympathetic responsiveness with regard to HR regulation can be extracted from the identified coupling mechanisms. We analyzed data collected from 29 human subjects before and after 16 days of head-down-tilt bed rest (simulated microgravity). Statistical analyses showed that parasympathetic and sympathetic responsiveness was impaired by bed rest. A lower sympathetic responsiveness and a higher parasympathetic responsiveness measured before bed rest identified individuals at greater risk of OI before and after bed rest. We propose an algorithm to predict OI after bed rest from measures obtained before bed rest. 相似文献
996.
Yonah Z.O. El-Serafi A.M. Krause A.E. 《Industrial Electronics, IEEE Transactions on》1990,37(6):576-581
A feasibility study on the use of a digital computer as a variable-amplitude variable-frequency oscillator which generates two-phase sinusoidal excitation control signals for a dual-excited synchronous generator is described. The oscillator uses two input signals. One input signal is used to control the frequency of the oscillator outputs, and the other is used to control their amplitudes. By a single variable, the software can be configured to vary the oscillator frequency range and to greatly reduce (almost eliminate) the harmonic distortion of the output signals. The harmonic distortion is constant and independent of the output frequency for each possible oscillator frequency range. The software-based oscillator design is flexible and can be used to generate different types of multiphase signal waveforms 相似文献
997.
998.
999.
C Jourdan-Le Saux O Le Saux T Donlon CD Boyd K Csiszar 《Canadian Metallurgical Quarterly》1998,51(2):305-307
OBJECTIVE: bcl-2 is a protein which prohibits programmed cell death. The purpose of this study was to determine whether bcl-2 staining was related to traditional prognostic factors and/or recurrence in patients with endometrial carcinoma. METHODS: One hundred twenty consecutively surgically treated patients with endometrial carcinoma had their tumors studied immunohistochemically for bcl-2 staining. RESULTS: The mean follow-up of the patients was 53 months with a median of 56 months (range 30 to 68 months). bcl-2 staining was positive in 44.0% of patients with endometrioid carcinomas and in 23. 1% of patients with nonendometrioid carcinomas (P < 0.001). Increasing depth of invasion (P = 0.014), grade (P = 0.011), and FIGO stage (P = 0.018) were each correlated with decreasing bcl-2 staining. bcl-2 staining was positive in 44.1% of patients whose tumors showed no lymphovascular space invasion and in 11.1% of patients with lymphovascular space invasion (P < 0.001). Only 1 of 26 patients with recurrent disease had persistence of bcl-2 staining. Multivariate analysis revealed FIGO stage (P = 0.0051), histologic grade (P = 0.050), and lack of staining for bcl-2 (P = 0.012) to be independent predictors of recurrence. CONCLUSION: bcl-2 persistence is more common in endometrioid than in nonendometrioid adenocarcinomas of the endometrium. It appears to be inversely correlated with the universally recognized prognostic factors of depth of invasion, histologic grade, and FIGO stage. Lack of bcl-2 persistence was an independent predictor of recurrence of disease. This group of patients continues to be followed to determine the role of bcl-2 persistence or lack of persistence as a predictor of 5-year survival of patients with endometrial carcinoma. 相似文献
1000.
Telemedicine in the USA: standardization through information management and technical applications 总被引:1,自引:0,他引:1
Choi Y.B. Krause J.S. Hyewon Seo Capitan K.E. Kyusuk Chung 《Communications Magazine, IEEE》2006,44(4):41-48
In this article, we describe the need for telemedicine standards and classify various standards of telemedicine. The emerging issues in telecommunications standards, the application of these standards in the health care industry, and future development directions of telemedicine standards are described. Especially, the telemedicine code standardization of drugs and health care providers, multimedia-conferencing-based ISO telemedicine standards, information security management, wireless technology advances for telemedicine using sensor networks, and future standardization issues and considerations are introduced and discussed in detail. 相似文献