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Three- and four-ring polyamides containing N-methylimidazole and N-methylpyrrole, and their hairpin-linked derivatives, bind side-by-side in the minor groove of DNA in a sequence-specific manner. The sequences recognized by side-by-side molecules are dependent on the pairings of the polyamide rings to the bases. In this study we report a mathematical model for estimating the free energies of binding for γ-aminobutyric acid-linked polyamides to 5- and 6-bp DNA sequences. The model parameters are calibrated by a least-squares fit to 35 experimental binding constants. The model performs well in cross-validation experiments and the parameters are consistent with previously proposed empirical rules of polyamide–DNA binding. We apply the model to the design of targeted polyamides, evaluating the ability of the proposed polyamides to bind to a DNA sequence of interest while minimizing binding to the remaining DNA sequences.  相似文献   
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A review of 179 autopsies was undertaken over a 1-year period to determine if clinically useful information was obtainable from coroners post mortems performed on patients referred from the A&E department. Fifty-six patients had undergone unsuccessful resuscitation. The leading causes of death were heart disease and trauma. Discrepancies between the diagnosis made during resuscitation and the cause of death found at autopsy were revealed especially in those dying from noncardiac causes. Iatrogenic trauma from resuscitation attempts occurred in a significant number of cases. It is suggested that review of selected Coroners post mortems should be part of departmental audit, with a view to improving clinical skills.  相似文献   
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C Strange  L Halstead  M Baumann    S A Sahn 《Thorax》1990,45(4):300-301
A patient with Wegener's granulomatosis rapidly developed a circumferential subglottic stenosis while on a cyclophosphamide regimen that had caused resolution of systemic symptoms and pulmonary infiltrates. The stenosis developed in the area of previously noted tracheal ulceration and responded satisfactorily to carbon dioxide laser therapy.  相似文献   
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One hundred fourteen patients scheduled to undergo elective cholecystectomy were prospectively randomized into one of four treatment groups to study the potential benefits of esophagogastric decompression with and without immediate postoperative enteral nutrition. Group I was the control, and patients received only iv fluids and were allowed to eat as tolerated. Group II patients received iv fluids and esophagogastric decompression. Group III patients received esophagogastric decompression and enteral sterile water through the duodenal feeding lumen. Group IV patients received esophagogastric decompression and infusion of an elemental diet through the feeding lumen. The surgical techniques were standardized for all patients. The results of the study indicated no statistically or clinically significant differences among any of the treatment groups regarding; (1) need for parenteral analgesics or antiemetics, (2) tolerance of regular diet, (3) postoperative day of discharge, and (4) postoperative day that other discharge criteria were met. It is concluded that there is no objective benefit to the routine use of esophagogastric decompression with or without enteral nutrition in elective cholecystectomy patients.  相似文献   
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We have presented the case of a 32-year-old man who sustained blunt trauma to the chest in a motor vehicle accident. Plain roentgenograms showed a widened mediastinum and pneumomediastinum, and an esophagogram with water-soluble contrast material showed an esophageal laceration at the T-4 level.  相似文献   
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