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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   
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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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BACKGROUND: It is controversial whether the cognitive deficit in schizophrenia is better characterized as generalized or as reflecting relatively independent deficits in different cognitive domains. The issue has implications for assessment practice, intervention design, and the exploration of schizophrenia genetics. METHODS: We used a specialized structural equation modeling approach, single common factor analysis, to explore the relative importance of generalized versus independent cognitive deficits in schizophrenia. Eighteen subtest scores from the Wechsler Adult Intelligence Scale-III and the Wechsler Memory Scale-III were included in the analysis. We analyzed these data for 97 schizophrenia or schizoaffective disorder outpatients and 87 healthy control subjects. RESULTS: Approximately two thirds of the overall effect of a schizophrenia diagnosis on cognitive performance was mediated through a single common factor. The Wechsler subtest scores showed almost uniformly strong relationships with this factor. The independent associations of group status with the subtest scores were smaller in magnitude and only selectively significant. CONCLUSIONS: The relatively greater magnitude of illness effects mediated through the common factor in this analysis, compared with the specific, independent effects, suggests that a generalized cognitive deficit is a core feature of schizophrenia.  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   
8.
OBJECTIVES: The wider study aimed to evaluate specialists' outreach clinics in relation to their costs, processes, and effectiveness, including patients' and professionals' attitudes. The data on processes and attitudes are presented here. DESIGN: Self administered questionnaires were drawn up for patients, their general practitioners (GPs) and specialists, and managers in the practice. Information was sought from hospital trusts. The study formed a pilot phase prior to a wider evaluation. SETTING: Nine outreach clinics in general practices in England, each with a hospital outpatient department as a control clinic were studied. SUBJECTS: The specialties included were ear, nose, and throat surgery; rheumatology; and gynaecology. The subjects were the patients who attended either the outreach clinics or hospital outpatients clinics during the study period, the outreach patients' GPs, the outreach patients' and outpatients' specialists, the managers in the practices, and the NHS trusts which employed the specialists. MAIN OUTCOME MEASURES: Process items included waiting lists, waiting times in clinics, number of follow up visits, investigations and procedures performed, treatment, health status, patients' and specialists' travelling times, and patients' and doctors' attitudes to, and satisfaction with, the clinic. RESULTS: There was no difference in the health status of patients in relation to the clinic site (ie, outreach and hospital outpatients' clinics) at baseline, and all but one of the specialists said there were no differences in casemix between their outreach and outpatients' clinics. Patients preferred, and were more satisfied with, care in specialists' outreach clinics in general practice, in comparison with outpatients' clinics. The outreach clinics were rated as more convenient than outpatients' clinics in relation to journey times; those outreach patients in work lost less time away from work than outpatients' clinic patients due to the clinic attendance. Length of time on the waiting list was significantly reduced for gynaecology patients; waiting times in clinics were lower for outreach patients than outpatients across all specialties. In addition, outreach patients were more likely to be first rather than follow up attenders; rheumatology outreach patients were more likely than hospital outpatients to receive therapy. GPs' referrals to hospital outpatients' clinics were greatly reduced by the availability of outreach clinics. Both specialists and GPs saw the main advantages of outreach clinics in relation to the greater convenience and better access to care for patients. Few of the specialists and GPs in the outreach practices held formal training and education sessions in the outreach clinic, although over half of the GPs felt that their skills/expertise had broadened as a result of the outreach clinic. CONCLUSIONS: The processes of care (waiting times, patient satisfaction, convenience to patients, follow up attendances) were better in outreach than in outpatients' clinics. However, waiting lists were only significantly reduced for gynaecology patients, despite both GPs and consultants reporting reduced waiting lists for patients as one of the main advantages of outreach. Whether these improvements merit the increased cost to the specialists (in terms of their increased travelling times and time spent away from their hospital base) and whether the development of what is, in effect, two standards of care between practices with and without outreach can be stemmed and the standard of care raised in all practices (eg, by sharing outreach clinics between GPs in an area) remain the subject of debate. As the data were based on the pilot study, the results should be viewed with some caution, although statistical power was adequate for comparisons of sites if not specialties.  相似文献   
9.
In 1993, a case-control study by the Health and Safety Executive (HSE) assessed the risk of leukaemia and non-Hodgkin's lymphoma (LNHL) among children of fathers employed at the Sellafield nuclear installation in relation to paternal preconceptional irradiation (PPI). It concluded that the statistical association between risk of LNHL and PPI was confined to children born in the village of Seascale, where the dose-response was extremely high and very significant. In contrast, in 2002, a Cumbrian birth cohort study, investigating largely the same cases, concluded that this statistical association was not significantly different among children born inside and outside Seascale and estimated the dose-response inside Seascale to be much lower. This review makes a detailed comparison of the two studies, considering their design, data and analyses. The differences between their findings are due to: (i) differences in the distribution of offspring-years which are differential with respect to dose category and Seascale birth status, (ii) a non-Seascale high-dose case included in the Cumbrian but not the HSE study, (iii) differences between analyses using categorical and continuous PPI dose and (iv) the presence of Seascale controls with PPI over 200 mSv in the Cumbrian but not the HSE study.  相似文献   
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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   
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