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顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究   总被引:5,自引:0,他引:5  
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。  相似文献   
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Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
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AIMS: Experimental studies have demonstrated that bone marrow (BM) cells can induce angiogenesis in ischaemic myocardium. Recently, several non-randomized pilot studies have also suggested that direct BM cells implantation appears to be feasible and safe in patients with severe coronary artery diseases (CAD). METHODS AND RESULTS: We performed a randomized, blinded, and placebo-controlled trial in 28 CAD patients. After BM harvesting, we assigned patients to receive low dose (1 x 10(6) cells/0.1 mL, n = 9), high dose (2 x 10(6) cells/0.1 mL, n = 10) autologous BM cells or control (0.1 mL autologous plasma/injection, n = 9) catheter-based direct endomyocardial injection as guided by electromechanical mapping. Our primary endpoint was the increase in exercise treadmill time and our secondary endpoints were changes in Canadian Cardiovascular Society (CCS) and New York Heart Association (NYHA) class, and myocardial perfusion and left ventricular ejection fraction (LVEF) assessed by single-photon emission computed tomography and magnetic resonance imaging, respectively. A total 422 injections (mean 14.6 +/- 0.7 per patient) were successfully performed at 41 targeted ischaemic regions without any acute complication. Baseline exercise treadmill time was 439 +/- 182 s in controls and 393 +/- 136 s in BM-treated patients, and changed after 6 months to 383 +/- 223s and 464 +/- 196 s [BM treatment effect +0.43 log seconds (+53%), 95% CI 0.11-0.74, P = 0.014]. Compared with placebo injection, BM implantation was associated with a significant increase in LVEF (BM treatment effect +5.4%, 95% CI 0.4-10.3, P = 0.044) and a lower NYHA class (odds ratio for treatment effect 0.12, 95% CI 0.02-0.73, P = 0.021) after 6 months, but CCS reduced similarly in both groups. We observed no acute or long-term complications, including ventricular arrhythmia, myocardial damage, or development of intramyocardial tumour or calcification associated with BM implantation. CONCLUSION: Direct endomyocardial implantation of autologous BM cells significantly improved exercise time, LVEF, and NYHA functional class in patients with severe CAD who failed conventional therapy.  相似文献   
6.
Background In recent years, the number of women entering the field of emergency medicine (EM) has increased.
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM.  相似文献   
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BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  相似文献   
9.
To develop guidelines for clinical magnetic resonance imaging of the liver, the authors undertook an animal study to investigate the effect of dose and pulse sequence on liver signal intensity in gadopentetate dimeglumine—enhanced echo-planar imaging. Serial imaging of the liver was performed in anesthetized rats after intravenous administration of five different doses (0.01, 0.05, 0.1, 0.2, and 0.5 mmol/kg) of contrast agent, with six different pulse sequences. The results show that gadopentetate dimeglumine—enhanced echo-planar images obtained during the perfusion phase can yield either positive (due to increased T1 relaxation rates) or negative (due to susceptibility-induced increased T2 relaxation rates) liver enhancement depending on choice of pulse sequence and dose. At the current clinically recommended dose of 0.1 mmol/kg, maximal liver signal enhancement was seen with a T1-weighted inversion-recovery sequence, while maximal liver signal diminution was seen with a T2*-weighted gradient-echo sequence. The authors conclude that gadopentetate dimeglumine—enhanced echo-planar imaging can provide T1, T2, and T2* contrast that may be exploited for both lesion detection and lesion characterization.  相似文献   
10.
A 16 year old girl with post-streptococcal glomerulonephritis developed acute rheumatic fever 19 days afterwards. Previous publications on concurrent post-streptococcal glomerulonephritis and acute rheumatic fever are reviewed.  相似文献   
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