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21.
为了寻找毒性低、增敏作用强的乏氧细胞放射增敏剂,设计并合成了一系列5-溴-,5-甲基-,和5-未取代的3-硝基-1,2,4-三唑-1-乙酰胺类化合物,用HeLaS3细胞进行了体外试验。结果表明5-溴取代衍生物的增敏作用强于相应的5-甲基-或5-未取代的硝基三唑衍生物,但是它们的毒性亦增大。修饰1位乙酰胺侧链也可以改变化合物的增敏作用和亲脂性。在所测定的化合物中TA-101[2-(3-硝基-1-三唑基)乙酰胺]由于有高的增敏作用和低亲脂性,可能是一个有希望的放射增敏剂。 相似文献
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K C Leung K P Fung C C Yu Y M Choy C Y Lee 《Clinica chimica acta; international journal of clinical chemistry》1977,74(1):43-49
The N-acetyl-beta-glucosaminidase activity in hydatidiform mole is two-fold higher than that in full-term placenta. Qualitatively, the enzymes from the two tissues are similar with respect to KM values and pH optima. Both enzymes also contain a new isoenzyme form detectable by polyacrylamide gel electrophoresis. However, the molar enzyme is more susceptible to heat denaturation, presumably due to the presence of a higher level of the heat-labile isoenzyme form A in this tissue. Data are also presented incicating that the placenta is not the source of the N-acetyl-beta-glucosaminidase activity in maternal serum. 相似文献
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Percutaneous drainage of chest abscesses in children 总被引:1,自引:0,他引:1
Seven patients ranging in age from 3 to 18 years underwent percutaneous drainage of eight intrathoracic abscesses. Five of the abscesses were mediastinal or paramediastinal and resulted from esophageal perforation or esophageal anastomotic leakage. The abscesses resolved in each case, with a mean catheter drainage time of 28 days and no need for surgical intervention. Three of the abscesses were intrapulmonary, and each lay adjacent to a pleural surface. All three lung abscesses resolved within 19-24 days, without thoracotomy or wedge resection. 相似文献
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Cooper C Choy E;Arthritis Research Campaign's Clinical Trials Committee 《Rheumatology (Oxford, England)》2003,42(6):713-715
Competing demands for scarce healthcare resources have accentuatedthe requirement for routine clinical practice to be evidence-based.One of the benchmarks for evidence-based medicine is the appropriatelyconducted randomized controlled trial (RCT). Although epidemiologicalstudies, whether casecontrol or cohort in design, havecontributed enormously to the generation of hypotheses and permitthe controlled evaluation of therapeutic interventions, theyare susceptible to biases through selection, information ascertainmentand confounding. While RCTs are also susceptible to such biases,the process of randomization and of blinded evaluation of outcomespermits the closest approximation in clinical research to theconduct of a hypothesis-testing laboratory experiment. Historically,there have been several obstacles to the execution of high-qualityRCTs to address important rheumatological questions. One 相似文献
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Detection of left ventricular dysfunction after acute myocardial infarction: comparison of clinical, echocardiographic, and neurohormonal methods. 总被引:11,自引:0,他引:11 下载免费PDF全文
A M Choy D Darbar C C Lang T H Pringle G P McNeill N S Kennedy A D Struthers 《Heart (British Cardiac Society)》1994,72(1):16-22
OBJECTIVE--The SAVE study showed that captopril improves mortality in patients with left ventricular dysfunction after myocardial infarction and that this benefit occurred even in patients with no clinically overt heart failure. On the basis of this, it seems important to identify correctly which patients have left ventricular dysfunction after a myocardial infarction. The objective was to compare various methods of identifying patients with left ventricular dysfunction (left ventricular ejection fraction, LVEF, < or = 40%) after acute myocardial infarction. The methods compared were echocardiography (quantitative and qualitative visual assessment), clinical evaluation (subjective assessment and three clinical score methods), and measurement of plasma concentrations of cardiac natriuretic peptide hormones (atrial and brain natriuretic peptides, ANP and BNP). DESIGN--Cross sectional study of left ventricular function in patients two to eight days after acute myocardial infarction. SETTING--Coronary care unit of a teaching hospital. PATIENTS--75 survivors of a recent myocardial infarction aged 40 to 88 with no history of cardiac failure and without cardiogenic shock at the time of entry to the study. MAIN OUTCOME MEASURES--Sensitivities and specificities of the various methods of detecting left ventricular dysfunction were calculated by comparing them with a cross sectional echocardiographic algorithm for LVEF. RESULTS--Clinical impression was poor at identifying LVEF < 40% (sensitivity 46%). Clinical scoring improved this figure somewhat (modified Peel index sensitivity 64%). Qualitative visual assessment echocardiography was a more sensitive method (sensitivity 82%) for detecting LVEF < 40%. Plasma BNP concentration was also a sensitive measure for detecting left ventricular dysfunction (sensitivity 84%) but plasma ANP concentration was much poorer (sensitivity 64%). CONCLUSION--Left ventricular dysfunction is easily and reliably detected by echocardiographic measurement of LVEF and also by a quick qualitative echocardiographic assessment but is likely to be missed by clinical assessment alone. High concentrations of plasma BNP maybe another useful indicator of left ventricular dysfunction, particularly in hospitals where not all patients can be screened by echocardiography or radionuclide ventriculography after myocardial infarction. 相似文献
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A feasibility study on using tablet personal computers for self‐reported symptom assessment in newly diagnosed lung cancer patients 下载免费PDF全文
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Lehua B Choy Heidi Hansen Smith Justine Espiritu Earl Higa Thomas Lee Jay Maddock 《Hawai'i Journal of Medicine & Public Health》2015,74(10):348-351
In 2011, a small pilot bike share program was established in the town core of Kailua, Hawai‘i, with funding from the Hawai‘i State Department of Health. The Kailua system consisted of two stations with 12 bicycles, and the goal was to secure additional funding to expand the station network in the future. Community feedback consistently indicated support for the bike share program. However, system metrics showed low levels of usage, averaging 41.5 rides per month (2011–2014). From observational data, users were primarily tourists. With minimal local staff, the bike share program had limited resources for promotion and education, which may have hindered potential use by local residents. Management of station operations and bike maintenance were additional, ongoing barriers to success. Despite the challenges, the pilot bike share program was valuable in several ways. It introduced the bike share concept to Hawai‘i, thereby helping to build awareness and connect an initial network of stakeholders. Furthermore, the pilot bike share program informed the development of a larger bike share program for urban Honolulu. As limited information exists in the literature about the experiences of smaller bike share programs and their unique considerations, this article shares lessons learned for other communities interested in starting similar bike share programs. 相似文献