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11.
Reactive oxygen species and human spermatozoa: physiology and pathology   总被引:20,自引:1,他引:19  
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial.  相似文献   
12.
Teaching psychiatric ethics   总被引:1,自引:0,他引:1  
S Bloch 《Medical education》1988,22(6):550-553
In the last decade, we have witnessed a burgeoning of interest in ethical issues amongst psychiatrists. Teaching of the subject, however, remains at a rudimentary stage. Various approaches to such instruction are available, particularly modelling (students observe their experienced counterpart), the case method (examining specific clinical situations which involve a need for ethical decision-making), and the seminar approach (trainees are exposed to a core body of knowledge, mainly theoretical in nature). Faced with these different teaching models, the University of Oxford Department of Psychiatry has opted for a blend of all three approaches, which incorporates two goals: an increase in the trainees' sensitivity to the many intricate moral dilemmas facing the psychiatric profession; and their familiarity with salient concepts in moral philosophy which constitute a basis for ethical reasoning and which have a bearing on clinical practice. The teaching programme comprises the following: a pair of trainees prepares a presentation on an aspect of psychiatric ethics under the supervision of a senior psychiatrist. A moral philosopher assumes the role of discussant of the ethical problems raised by the trainees; this is followed by a general discussion. Topics have included involuntary hospitalization, dual loyalty, suicide, psychiatric diagnosis, and ethical issues in various spheres of psychiatric practice such as sex therapy, psychotherapy and child psychiatry. The approach has worked effectively and proved rewarding to all participants involved.  相似文献   
13.
E. Soncini  A. Petit   《ITBM》2002,23(3):172
Regulations evolve and risks management becomes one of the biomedical engineers' preoccupations. Thus, risks are various, and consequently it is difficult to identify, to manage and to bring them under control. Furthermore, regulations exist for sectors like healthcare technology monitoring, but it is not the same thing for instance for the risks linked to the maintenance. Thus regulation in the sector of maintenance evolves and the decree of the 1st July law of health safety is going to modify the biomedical environment. The goal of this work is to study the tools and the methods of risks management that have been used for several years in the industrial field and to use them for some biomedical equipment like monitors or IV pumps. These methods adapted to these equipment will allow us to determine some appropriate rules of maintenance.  相似文献   
14.
Objective: Considering the growing use of cellular phones and the fast appearance of new phone models, the electromagnetic interference of currently popular cellular phones on electronic medical equipment was tested. Methods: Three Personal Communication System cellular phones were put at different distances from multiple electronic medical devices, the interference effect was observed and the electromagnetic field strength measured with a spectrum analyser. Results: Only two small pieces of equipment, the CO2 airway adapter and the haemoglucostix meter were affected and then only when the phone was in very close proximity. Conclusion: Compared to the results of our study in 1997 testing Global System for Mobile Communication phones, the Personal Communication System phones generated less electromagnetic interference. However a much larger scaled study and an accurate international electromagnetic interference standard are recommended before any change in the current restrictive hospital policy on mobile phone usage could be recommended.  相似文献   
15.
This report describes a model for identifying sets of teaching abilities considered to be effective for medical school teaching staff, based on roles teachers assume and functions they are expected to perform as instructors. The specification of these teaching abilities was the first step in the development of a comprehensive course on Medical Instruction at the Basic Institute of Medical and Agricultural Biology of the State University of Sao Paulo, Botucatu, Brazil, where the senior author is employed. The work was based on the assumption that medical school teachers are expected to assume a variety of teaching roles and that identification and specification of the abilities that define their roles can result in more effective and efficient teaching.  相似文献   
16.
重视医学信用伦理的研究与开发   总被引:7,自引:3,他引:4  
医疗行业市场化是必然趋势。在医疗行业市场化进程中,医学伦理道德除了道德价值之外,还含有积极的经济内涵。医学伦理道德也是重要的医疗资源,通过参与医疗市场资源的配制和运作,也可以产生经济效益,转化为医疗资本。医疗行业要重视医学伦理道德资源的开发。信用伦理是在市场经济条件下形成的,这是医学伦理学所面临的新课题。笔者认为,不说谎、不期诈,兑现承诺,保证医疗质量,发扬医学人道主义,是医学信用伦理的四项基本标准。  相似文献   
17.
从产业组织学角度看中国医疗广告   总被引:1,自引:0,他引:1  
吴国术 《中国药事》2005,19(9):532-534
随着医疗卫生体制改革的全面推行,医疗行业竞争日趋激烈,众多医院采取不同的策略组合以提高其核心竞争力,而广告正是其主要的营销策略之一.本文在对医疗广告特性、类别、作用进行分析的基础上,从产业组织学角度阐述了医疗广告与医疗市场结构、市场效益的关系,提出了中国医疗广告的发展趋势.  相似文献   
18.
A questionnaire survey of career choices was carried out among 112 medical graduates, after one year's internship (group I), during their National Youth Corps programme in Kaduna, Lagos, Cross River and Oyo states of Nigeria, and 365 final-year medical undergraduates (group 2) in the colleges of medicine in the corresponding states. A total of 13% in group I and 40% in group 2 were undecided as regards their first choice. Obstetrics and gynaecology was the most popular first choice in both groups. General practice ranked fifth among group I, but displaced surgery to rank second among group 2. The differences were statistically significant. A total of 41% of group I and 46% of group 2 preferred to work in a teaching hospital, reflecting the high preference for surgical specialties. Twenty-six per cent and 33.7% of respondents in groups 1 and 2 respectively wished to own their own practice or work in the private sector. General practice is a new specialty and its growth is supported by a national postgraduate training programme. A shift towards general practice is seen compared with previous studies of career preference among Nigerian medical graduates and students. This may be due to a changing balance of supply and demand in the medical work-force, or a better assessment of the nation's health problems and manpower needs.  相似文献   
19.
Regulation of erythropoietin production   总被引:6,自引:0,他引:6  
  相似文献   
20.
Variation in opinions of medical experts is a problem for both the legal and medical profession. This is particularly relevant in breast imaging. BreastScreen Queensland and New South Wales have developed a review protocol to assess ‘reasonableness’ of radiological opinions. It is hoped that the protocol will be acceptable to the courts and will result in a fair outcome for all parties involved in a medico-legal dispute.  相似文献   
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