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1.
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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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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In co-cultures of either the murine pre-B cell line J13, fetal liver cells, or adult peritoneal or bone marrow cells with ST2 mouse bone marrow stromal cells in the presence of granulocyte/macrophage colony-stimulating factor (GM-CSF), the development of CD5+ macrophages was demonstrated by immunohistochemical staining and flow cytometry. Although CD5+ macrophages were not present in the peritoneal cavities of normal mice, approximately 30% of the peritoneal macrophages in viable motheaten (mev/mev) mice, deficient in SHP-1 protein tyrosine phosphatase, expressed cell surface CD5 and B220, markers for B cells. In the mev/mev mice, GM-CSF level in peritoneal fluid was increased significantly. At 5 days after daily intravenous injection with GM-CSF, many CD5+ macrophages appeared in the peritoneal cavity and in omental milky spots of normal mice but fewer in osteopetrosis (op) mutant mice, deficient in macrophage (M)-CSF. These results indicate that GM-CSF, in combination with M-CSF, induces the development and differentiation of CD5+ macrophages in the peritoneal cavity, particularly in the omental milky spots of mice. In the peritoneal cavity of GM-CSF-treated mice, the percentages of hematopoietic progenitor cells doubly positive for CD5 and CD34 or c-kit and of macrophage precursor cells doubly positive for CD5 and ER-MP58 or ER-MP20 were increased significantly during the development of CD5+ macrophages and CD5 B cells, suggesting that CD5+ macrophages and B cells may share a bipotential progenitor in vivo.  相似文献   
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BACKGROUND: 'Hospital At Home' schemes are set to increase in the United Kingdom (UK) in response to the NHS Plan. To date, little detailed work has been done on the acceptability of these schemes to patients and their carers. AIM: To compare Hospital at Home patient and carer satisfaction with hospital care. DESIGN OF STUDY: Pragmatic randomised controlled trial. SETTING: Consecutive patients assessed as suitablefor the Leicester Hospital at Home scheme were randomised to Hospital at Home or one of three acute hospitals in the city. METHOD: Patient satisfaction was assessed two weeks after randomisation, or at discharge if later using a six-item questionnaire. Patients' and carers' views of the services were assessed by semistructured interviews. RESULTS: One hundred and two patients were randomised to Hospital at Home and 97 to hospital. Forty-eight (47%) patients in the Hospital at Home arm and 35 (36%) in the hospital arm completed the satisfaction questionnaire, representing 96% and 85% of those eligible, respectively. Total scores were significantly higher in the Hospital at Home (median = 15) than in the hospital group (median = 12). (P<0.001, Mann-Whitney U-test.) Responses to all six questions favoured Hospital at Home, with all but one of these differences being statistically significant. In the Hospital at Homegroup, 24 patients and 18 of their carers were interviewed; in the hospital group 18 patients and seven of their carers were interviewed. Themes emerging from these interviews were that patients appreciated the more personal care and better communication offered by Hospital at Home and placed great value on staying at home, which was seen to be therapeutic. Patients largely felt safe in Hospital at Home, although some would have felt safer in hospital. Some patients and carers felt that better medical care would have been provided in hospital. Carers felt that the workload imposed by Hospital at Home was no greater than by hospital admission and that the relief from care duties at home would be counterbalanced by the added strain of hospital visiting. CONCLUSIONS: Patient satisfaction was greater with Hospital at Home than with hospital. Reasons included a more personal style of care and a feeling that staying at home was therapeutic. Carers did not feel that Hospital at Home imposed an extra workload.  相似文献   
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Guidelines urge general practitioners (GPs) to discuss smoking with patients as frequently as possible. Using data collected before and after consultations, this study confirms that GPs are more likely to discuss smoking in the context of smoking-related problems. Encouraging GPs to make greater use of problem-orientated opportunities to discuss smoking may have more effect on rates of advice giving than urging them to advise all smokers.  相似文献   
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Fasting serum lipid levels and changes in plasma glucose, fatty acid non-esterified (Nefa), and blood pyruvate levels during intravenous glucose tolerance tests were measured in 13 normal subjects before and one, five, and 15 days after the administration of 1-triiodothyronine (T3) calculated as 6 mug/kg body weight.Significant increases in the mean basal metabolic rate and the mean fasting plasma Nefa level occurred within 10 to 17 hours of a single dose of T3, while a rise in the mean fasting plasma glucose concentration just failed to achieve significance. Fasting concentrations of blood pyruvate and serum triglyceride were unaffected. A significant fall in serum cholesterol levels was produced and lasted at least five days. All other indices returned to normal by five days.During intravenous glucose tolerance tests performed at intervals after T3 administration no change in plasma glucose levels from control values was seen. Mean plasma Nefa and blood pyruvate levels, however, were significantly raised above control values during the early stages of the test 10 to 17 hours after T3. The relationship between these findings and those observed in clinical thyrotoxicosis is discussed.  相似文献   
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