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Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst...  相似文献   
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This study evaluated the effects of tobacco Purchase, Use and Possession (PUP) laws on student perceptions of adolescent tobacco use within towns and schools. Twenty‐four towns were randomly assigned into two conditions, the experimental condition (E PUP) involved efforts to increase both PUP law enforcement and reduce minors' access to commercial sources of tobacco, whereas the control condition (C) focused only on efforts to reduce minors' access to commercial sources of tobacco. A hierarchical linear modeling analytical approach was selected due to the multilevel data and nested design. The present study found that over time, youth in the experimental PUP condition observed less youth tobacco usage at school and in their town, and perceived lower rates of tobacco among their peers at school and among friends than youth in the control condition. The findings suggest that PUP law enforcement might be used to strengthen community norms against youth tobacco use.  相似文献   
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R C Hunt  D M Bryan  V S Brinkley  T W Whitley  N H Benson 《JAMA》1991,265(15):1982-1984
This study assessed the capabilities of a traditional and an amplified stethoscope used by flight nurses to assess breath sound during air medical transport in an MBB BO-105 helicopter. We developed a normal breath sound model using a prerecorded tape of breath sounds interspersed with segments without breath sounds; the recorder had been placed in the chest wall of a resuscitation training manikin. Flight nurses completed control listening sessions in a quiet environment and experimental sessions during flight using a traditional stethoscope for half of the sessions and an amplified stethoscope for the remaining half. In the quiet environment, flight nurses accurately reported the presence or absence of breath sounds in 110 (92%) of 120 trials. During helicopter flight, none of the flight nurses heard breath sounds during any of the recorded segments with either the traditional stethoscope or the amplified stethoscope. We conclude that flight nurses are unable to hear normal breath sounds using a traditional or amplified stethoscope during flight in a medically configured MBB BO-105 helicopter. Improved stethoscopes, innovative methods of listening, and reduction of aircraft noise are potential solutions to the problems of breath sound assessment during air medical transport.  相似文献   
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Most publications citing the effectiveness of renal extracorporeal shock wave lithotripsy have used plain abdominal radiography to assess residual calculi after treatment. We compared radiologist sensitivity and specificity in the detection of calculi on plain abdominal radiographs versus conventional film-screen and digital renal tomograms in extracorporeal shock wave lithotripsy patients. Of the patients 50 were imaged before and within 24 hours after lithotripsy. Six radiologists evaluated the resultant 300 studies for the presence and location of calculi. The mean sensitivity for digital tomograms was 83% for pre-lithotripsy and post-lithotripsy studies, which was significantly higher than for plain abdominal radiography and conventional tomography after lithotripsy. However, there were significantly more false positive stone diagnoses associated with digital tomogram interpretation. Signal detection analysis verified the over-all superiority of digital tomography for post-extracorporeal shock wave lithotripsy imaging. Calculus detection by conventional and digital tomography is superior to detection by plain abdominal radiography. However, because we did not perform delayed imaging, it is not possible to say what impact digital tomography might have on the management of extracorporeal shock wave lithotripsy patients.  相似文献   
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To determine effect of interaction between dietary cholesterol and triglyceride, i.e., polyunsaturated to saturated (P:S) fatty acid ratio, on LDL metabolism, male cynomolgus macaques were fed purified diets for 83 wk with cholesterol levels of 0.01, 0.06 and 0.50 mg/kJ and P:S ratios of 0.5 and 0.9, oleic acid constant. There were six groups of five animals each (cholesterol, mg/kJ--P:S ratio): Group 1, 0.01--0.5; Group 2, 0.01--0.9; Group 3, 0.06--0.5; Group 4, 0.06--0.9; Group 5, 0.50-0.5; Group 6, 0.50-0.9. LDL (1.019 less than d less than 1.063 kg/L) and glucosylated LDL were iodinated for turnover studies. Hepatic LDL transport was determined using 125I-tyramine-cellobiose-LDL as tracer. Plasma cholesterol increased in proportion to dietary cholesterol, and concentrations (mmol/L) at 77-78 wk were (mean +/- SEM): Group 1, 434 +/- 0.31; Group 2, 3.03 +/- 0.14; Group 3, 8.28 +/- 1.48; Group 4, 7.34 +/- 1.31; Group 5, 15.54 +/- 1.44; Group 6, 15.54 +/- 1.41. LDL cholesterol was 45% higher in Group 1 (2.43 mmol/L) than in Group 2 (1.68 mmol/L). In vivo studies showed that LDL clearance was suppressed by excess dietary cholesterol; receptor-independent LDL clearance was relatively constant. Hepatic LDL protein transport was greater in Group 2 (P:S 0.9) compared with Group 1 (P:S 0.5). The LDL protein synthetic rate was lower in Groups 2, 4 and 6 (P:S 0.9) relative to Groups 1, 3 and 5 (P:S 0.5). We conclude that in this model hepatic LDL receptor activity is altered by degree of saturation in dietary triglycerides when dietary cholesterol is minimal, and that saturated dietary triglycerides enhance LDL protein secretion when dietary cholesterol is ample.  相似文献   
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