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1.
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   
2.
Stanford''s two decades of success in linking medical informatics and health services research in both training and investigational activities reflects advantageous geography and history as well as natural synergies in the two areas. Health services research and medical informatics at Stanford have long shared a quantitative, analytic orientation, along with linked administration, curriculum, and clinical activities. Both the medical informatics and the health services research curricula draw on diverse course offerings throughout the university, and both the training and research overlap in such areas as outcomes research, large database analysis, and decision analysis/decision support. The Stanford experience suggests that successful integration of programs in medical informatics and health services research requires areas of overlapping or synergistic interest and activity among the involved faculty and, hence, in time, among the students. This is enhanced by a mixture of casual and structured contact among students from both disciplines, including social interactions. The challenges to integration are how to overcome any geographic separation that may exist in a given institution; the proper management of relationships with those sub-areas of medical informatics that have less overlap with health services research; and the need to determine how best to exploit opportunities for collaboration that naturally occur.Training in medical informatics and health services research has been closely linked at Stanford University for almost two decades. Although the close linkage was deliberate, it was facilitated by historical circumstances, in particular the common academic structures in which both programs arose. In this paper, we describe some of that rationale and history, identifying the areas of overlap that we have pursued in coordinating the training opportunities for graduate students and fellows in both areas of study. As we shall note, the synergies have been great, and in some cases trainees have collaborated closely on research while also taking some of the same courses. We believe that these interactions can be a model for the design of training programs that encourage scholarly interactions between medical informatics and health services research. Although our initial charge was to describe both the successes and failures in integrating the programs, we found that we could not identify any outright failures and that it would be better to delineate the complexities and challenges that we have faced in bringing together these two disciplines.  相似文献   
3.
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   
4.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响.  相似文献   
5.
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   
6.
Early laparoscopic cholecystectomy for acute cholecystitis   总被引:4,自引:0,他引:4  
Background: The timing of laparoscopic cholecystectomy for acute cholecystitis remains controversial. Methods: One hundred ninety-four patients with acute cholecystitis were reviewed. The conversion rates for the various number of days of symptoms before surgery were analyzed. The conversion rate dramatically increased from 3.6% for those patients with 4 days of symptoms to 26% for those patients with 5 days of symptoms. The mean number of days of symptoms prior to surgery in those patients who underwent successful laparoscopic cholecystectomy was 4.1 as compared to 8.0 in those patients who required open cholecystectomy (p < 0.0001). Based on this data the patients were divided into two groups. Group 1 consisted of 109 patients who underwent laparoscopic cholecystectomy within 4 days of onset of symptoms and group 2 consisted of 85 patients who underwent laparoscopic cholecystectomy after more than 4 days following onset of symptoms. Results: The conversion rate from laparoscopic to open cholecystectomy was 15%. The conversion rate for group 1 was 1.8% as compared to 31.7% for group 2 (p < 0.0001). Indications for conversion were inability to identify the anatomy secondary to inflammatory adhesions (68%), cholecystoduodenal fistula (18%), and bleeding (14%). The major complication rate for group 1 was 2.7% as compared to 13% for group 2 (p= 0.007). The mortality rate for all patients with attempted laparoscopic cholecystectomy for acute cholecystitis was 1.5%. The average procedure time for group 1 was 100 ± 37 min vs 120 ± 55 min in group 2. The average number of postoperative hospital days in group 1 was 5.5 ± 2.7 days as compared to 10.8 ± 2.7 days in group 2. Conclusions: We advocate early laparoscopic cholecystectomy within 4 days of onset of symptoms to decrease major complications and conversion rates. This decreased conversion rate results in decreased length of procedure and hospital stay. Received: 28 March 1996/Accepted: 12 September 1996  相似文献   
7.
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
8.
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.  相似文献   
9.
High resolution magnetic resonance imaging (MRI) of the brain was performed on 18 male schizophrenic patients and 15 male normal control subjects using an identical imaging protocol. The number and size of T2 hyperintense foci were clinically quantified by an academic radiologist. Large foci (greater than or equal to 3 mm in diameter) were observed more frequently on patient images (7/18) than on control images (1/15). The imaging protocol detected high rates of focal hyperintensities, but no differences between patients and controls were noted in the total affected brain area (sum of focal areas) or in the presence or absence of foci.  相似文献   
10.
The use of high-flux dialysis in clinical practice increased rapidly despite an absence of reports on the clinical effectiveness of the technique. Mortality and hospital admission rates of patients treated with high-flux dialysis were evaluated and compared with those of patients treated with conventional dialysis in a hospital-based renal dialysis unit in northern California. By use of a retrospective, cross-over design, 253 patients enrolled in the dialysis unit from January 1987 to January 1991 were studied. During this period, 107 patients were treated with high-flux dialysis for at least 1 month, and all but 17 of them had received conventional dialysis before switching to high-flux dialysis. The remaining 146 patients were treated with only conventional dialysis. Of the 80 patients who died during the study period, 69 were receiving conventional dialysis and 11 were receiving high-flux dialysis. The multivariate analyses, adjusted for age, gender, ethnic background, type of renal failure, comorbid conditions, and duration of ESRD, showed that annual mortality was substantially less for patients treated with high-flux dialysis compared with that for patients treated with conventional dialysis (7 versus 20%; P < 0.001). The difference in the rate of hospital admissions was not statistically significant. In this nonexperimental study, methods were applied to control for selectivity bias and other factors that might confound the apparent treatment effect. The findings suggest that the potential benefits of high-flux dialysis are sufficient to justify further confirmation in a randomized, controlled trial.  相似文献   
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