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71.
The KUSIVAR is an expert system for mechanical ventilation of adult patients suffering from respiratory insufficiency. Its main objective is to provide guidance in respirator management. The knowledge base includes both qualitative, rule-based knowledge and quantitative knowledge expressed in the form of mathematical models (expert control) which is used for prediction of arterial gas tensions and optimization purposes. The system is data driven and uses a forward chaining mechanism for rule invocation. The interaction with the user will be performed in advisory, critiquing, semi-automatic and automatic modes. The system is at present in an advanced prototype stage. Prototyping is performed using KEE (Knowledge Engineering Environment) on a Sperry Explorer workstation. For further development and clinical use the expert system will be downloaded to an advanced PC. The system is intended to support therapy with a Siemens-Elema Servoventilator 900 C.  相似文献   
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Journal of the American Oil Chemists' Society - 1  相似文献   
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A triarylmethane dye 1 detects CN? from water and shows remarkable selectivity over other anions and dramatic color changes, in solution as well as when dyed. The pH stability of 1 in the range of 1.2–10.7 offers additional advantage in the sensing process under physiological conditions.  相似文献   
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OBJECTIVE: To identify and examine the indications, outcomes and potential risks of strabismus surgery in visually mature patients. DESIGN: Case series. SETTING: University-based referral practice in Edmonton. PATIENTS: A total of 222 patients (115 females and 107 males) aged 9 to 69 (mean 29) years who underwent strabismus surgery for various types of strabismus (as grouped by original diagnosis). All patients were followed for at least 6 weeks postoperatively. OUTCOME MEASURES: Previous surgery and deviation in prism dioptres (delta) (distance and near), sensory status (measured by the Titmus stereotest at near) and the presence of symptoms (diplopia, abnormal head posture or asthenopia), recorded preoperatively, 6 weeks postoperatively and at the last postoperative visit. RESULTS: The patients were followed for an average of 14 months postoperatively. At the last postoperative visit 187 patients (84%) were aligned to within 15 delta of orthotropia. Overall, 116 patients (52%) demonstrated some degree of stereopsis postoperatively, compared with 78 (35%) preoperatively. A total of 116 patients (52%) had symptoms preoperatively, including diplopia, abnormal head posture or asthenopia; 88 (76%) of the 116 had complete resolution of their symptoms. Six patients (4%) without diplopia preoperatively were found to have this symptom postoperatively. CONCLUSIONS: The findings suggest that most visually mature patients under-going strabismus surgery can expect functional benefits, including improvement of alignment, preservation and occasionally restoration of sensory fusion, and elimination of diplopia, abnormal head posture and asthenopia.  相似文献   
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Methods for reconciliation of spatial and temporal scales of data have become increasingly important as remote sensing data become more readily available and as the science of hydrology moves more heavily toward distributed modeling. The purpose of this paper is to develop a method to disaggregate coarse-resolution remote sensing data to finer scale resolutions that are more appropriate for use in hydrologic studies and water management. This disaggregation is done with the help of point measurements on the ground. The downscaling of remote sensing data is achieved by three main steps: initialization, spatial pattern mimicking, and assimilation. The first two steps are part of the main algorithm, and the last step, assimilation, is included for fine-tuning and to ensure further compatibility between the coarse-scale and fine-scale images. The assimilation step also incorporates the information coming from the point measurements. The approach has been applied and validated by downscaling images for two cases. In the first case, a synthetically generated random field is reproduced at fine and coarse resolutions. The downscaled image has been shown to match the spatial properties of the true image according to the variogram test as well as the magnitude of values according to the various univariate goodness-of-fit measures R2 = 0.91. In the second case, a soil moisture field from the Southern Great Plains (SGP 97) experiments is downscaled from a resolution of 800 m X 800 m to a resolution of 50 m X 50 m.  相似文献   
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The structure and biological activities of two disulphide isomersof a C-region deletion mutant of insulin-like growth factor-I(IGF-I) which has an Asn–Gly link engineered at the junctionof the A- and B-regions were studied before and after chemicalcleavage. Circular dichroism (CD) spectra and binding affinityto IGF binding protein 3 (IGFBP3) indicated that the treatmentwith hydroxylamine did not disrupt the overall tertiary foldof the hormones. Cleavage restored some binding affinity forthe IGF-I receptor in both isomers and weakly restored the abilityto stimulate incorporation of tritiated thymidine into DNA inNIH 3T3 fibroblasts transfected with the human IGF-I receptor.Cleavage also restored metabolic capacity, as measured by theability of the isomers to promote lipogenesis in isolated ratadipocytes through the insulin receptor. These results are consistentwith the theory that binding of IGF-I to the IGF-I receptorrequires a conformational change similar to that involved ininsulin binding the insulin receptor. The weak affinity forthe IGF-I receptor after cleavage is consistent with the beliefthat residues in the C-region interact with the IGF-I receptor.This structural difference between insulin and IGF-I gives eacha higher binding affinity for its own receptor.  相似文献   
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