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171.
本文介绍我们发展起来的.用于同时在胞内细胞分子水平、细胞骨架\细胞膜、以及细胞整体形态三个水平层次上.对单个活态细胞的结构与功能进行无扰、实时、原位检测的系列技术及其有关应用。  相似文献   
172.
液体表面张力系数及测量精度的分析   总被引:1,自引:0,他引:1  
王桂莲 《医学信息》2007,20(8):1349-1351
分子之间的相互作用产生分子力,阐述表面张力形成的基本原理。对表面张力系数的测量进行分析,讨论提高测量精度的方法。  相似文献   
173.
Introduction. Management of primary health care (PHC) systems in less developed countries is often impeded by factors such as poorly trained personnel, limited financial resources, and poor worker morale. This study explored the ability of local-level PHC supervisors in rural Nigeria to use quality assurance (QA) management methods to improve the quality of the PHC system. Methods. PHC supervisors from Bama Local Government Area were trained for 3 days in the use of QA methods and tools. The supervisors targeted the supervisory system and the health information system (HIS) for improvement. Health worker performance in diarrhoea case management was assessed, using a simulated case, to measure the impact of supervision. A HIS audit assessed data collection forms used by 17 PHC facilities. Gaps in quality were monitored over a 2-month study period and flaws in work processes were modified. Results. PHC supervisors introduced a checklist during monthly visits to facilities to monitor how workers managed cases of diarrhoea. Performance in history-taking, physical examination, disease classification, treatment and counselling improved over the evaluation period. The HIS audit found that a variety of reporting forms were used at PHC facilities. After HIS reporting was standardized, the number of health facilities using a daily disease registry significantly improved during the study period. Conclusions. QA management methods were used by PHC supervisors in Nigeria to improve supervision and the HIS. QA management methods are appropriate for improving the quality of the PHC in Nigeria and in other less developed countries where at least a minimal PHC infrastructure exists.  相似文献   
174.
Summary. The University Centre for Health Sciences (UCHS) or as it is referred to in French ‘Centre Universitaire des Sciences de la Santé’ (CUSS), became functional in 1969 with the enrolment of the first group of students. The objective of this training programme was to produce a scientifically sound, multipurpose doctor who would be fully operational in a rural setting with minimal equipment and supplies ( Monekosso 1970, 1972 ). The graduate had to be able to adapt readily to new situations and improvise whenever possible, calling for a high degree of competence and initiative. The training strategies adopted by UCHS in 1969 which met this requirement were later found to be in close concordance with the tenets of the World Conference on Medical Education held in Edinburgh in 1988, the Edinburgh Declaration. While some of the terminology may not have been worked out at the time, the programme developed embraced some new concepts hitherto untried or undeveloped:
  • — the problem-solving approach in the first to the sixth year;
  • — an integrated teaching approach during the first to sixth year of medical training;
  • — an integrated medicine internship in district hospitals in the sixth year;
  • — a community-based training approach throughout the training;
  • — team training of three different health professionals;
  • — competency-based training;
  • — health services linked research;
  • — health services linked training ( Monekosso & Quenum 1978 ).
The concordance of this programme to the Edinburgh Declaration is of great interest in realizing the World Federation for Medical Education programme and implementing the Edinburgh Declaration. The involvement of the three innovative medical schools in the planning stage of the curriculum explains this concordance.  相似文献   
175.
176.
头部电导纳图的导纳微分环及功率谱分析   总被引:2,自引:1,他引:1  
通过多例头部电纳图的导纳微分环面积和功率谱分析,发现陡直型和转折型波形,其功率谱中的某些指标有显著性差异(P<0.05),导纳微分环中的Ⅰ,Ⅱ,Ⅳ相面积也有显著性差异(P<0.05)。  相似文献   
177.
Assessment of the quality of life (QoL) of human immunodeficiency virus (HIV)-infected subjects is often based on questionnaires in which the items or questions are not seen to be relevant by patients, nor by the users of the data obtained. It therefore seemed appropriate to return to the issue. The methodological and bibliographical research as well as the consultations we conducted convinced us that the elaboration of a new questionnaire was both necessary and possible. In order to do so, we adopted methodological principles based on the Sickness Impact Profile development methodology. First a bibliographical research was conducted in order to study instruments already used for HIV infection. Then, experts concerned with HIV infection and members of patients' associations were interviewed to assess how opportune the development of a new instrument could be. Following this, a methodology was established for the design and construction of the new instrument. One hundred and eighteen candidate questions were generated from an analysis of the content of 20 patients' interviews, which were subsequently submitted to 102 patients, to obtain finally a set of 31 questions from the interpretation of the results obtained from classic psychometric analysis and also from non-classic methods (item response theory and Rasch model). The concept being measured is the impact of illness being experienced by HIV-infected subjects from their own perspective. The range of health states covered by this questionnaire relates to fairly mild conditions. Rasch analysis of this set of 31 questions (HIV-QL31) shows that it corresponds to one unidimensional construct. A single score can be calculated by simple summation of dichotomous response options. This score is highly reliable (Cronbach's coefficient = 0.93) and is also discriminant regarding the severity of clinical status.  相似文献   
178.
A multicenter, randomized Phase 2 study that compared patients, affected by colorectal liver metastases, who received intrahepatic arterial infusion with two different schedules of cisplatin, bolusvs. continuous infusion, and systemic 5-fluorouracil. PURPOSE: The aim of this study was to validate results of a previous Phase 2 trial on bolus cisplatin intrahepatic arterial infusion, which reported a 47 percent response rate and a 32 percent 4-year survival rate for Gennari's Stage 2 patients, with a high rate of neurologic, gastrointestinal, and hematologic toxicity. METHODS: One hundred nine patients were randomized in a Phase 2 study to receive cisplatin intrahepatic arterial infusion (24 mg/m2/day, 15, bolusvs. continuous infusion) and systemic intravenous 5-fluorouracil (250, 375, or 500 mg/m2/day, 15; escalating doses, respectively, at cycles I, II, III, and VI). To avoid neurotoxicity a maximum of six cycles was administered. RESULTS: Preliminary results for the 78 evaluable patients are similar to those of the previous study: response rate 46 percent and at a median follow-up of 16.5 months, the overall survival was 16.5 months, with 45 percent of the patients who received more than 3 cycles alive at 3 years. Toxicity, evaluable in 99 patients, showed a decreased incidence of neurotoxicity and a tolerable gastrointestinal and hematologic toxicity, lower in the cisplatin continuous infusion arm. CONCLUSION: This study clearly shows that cisplatin intrahepatic arterial infusion is able to provide a good palliative effect with a tolerable toxicity.This study was supported in part by Pharmacia-Deltec, Italy.  相似文献   
179.
Left ventricular function during exercise and recovery was investigated in patients with angina pectoris, ST segment depression during exercise and angiographically normal coronary arteries (syndrome X) using a continuous left ventricular function monitor with cadmium telluride detector (CdTe-VEST). Fourteen patients with syndrome X and 14 patients with atypical chest pain without ST segment depression during exercise and normal coronary arteries (control group) performed supine ergometric exercise after administration of 740–925 MBq of technetium-99m labelled red blood cells, and left ventricular function was monitored every 20 s using CdTe-VEST. Left ventricular ejection fraction (EF) response was impaired (55% increase from rest to peak exercise) in 11 or 14 patients with syndrome X but in none of the control patients. Resting EF was similar in the two groups (62.1%±6.7% in patients with syndrome X, 61.9%±6.2% in controls); however, EF increase from rest to peak exercise was lower in syndrome X (–3.1±9.5% vs 14.7%±7.4%, P <0.001). After cessation of exercise, all patients showed rapid EF increase over baseline and this EF overshoot was lower (19.3%±8.3% vs 26.4%±7.3%, P <0.001) with the time to EF overshoot longer (114±43 s vs 74±43 s, P<0.05) in patients with syndrome X. Thus, in patients with syndrome X, left ventricular dysfunction was frequently observed during exercise in spite of normal epicardial coronary arteries. Correspondence to: J. Taki  相似文献   
180.
This prospective study was completed to determine the influence of epidural anaesthesia on the fetoplacental circulation of normal subjects. Thirty-seven normal pregnant patients at term, undergoing elective Caesarean section, had Doppler measurements of the fetal umbilical artery blood flow velocity before and after epidural anaesthesia using lidocaine 2% without epinephrine. There were no differences in systolic/diastolic, resistance or pulsality indices following epidural anaesthesia. These results suggest that this technique has no adverse effect on fetoplacental circulation in normal non-labouring subjects. Cette étude prospective a pour but de déterminer l’influence de l’anesthésie épidurale sur la circulation foeto-placentaire dans le contexte d’une grossesse normale. Des indices de vélocité du flot de l’artère ombilicale foetale ont été mesurés par Doppler chez trentesept patientes gravides à terme, sans complications, programmées pour une césarienne élective, avant et après une anesthèsie épidurale utilisant la lidocaine 2% sans épinéphrine. Les indices de rapport systole/diastole, de résistance et de pulsatilité sont demeurés inchangés après l’induction de l’anesthésie épidurale. Ces constatations suggèrent que l’anesthésie épidurale n’a pas d’influence sur la circulation foetoplacentaire chez des patientes enceintes normales à terme qui ne sont pas en travail.  相似文献   
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