首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
This is the third of three papers that review international policies to control spending on drugs and to improve the efficiency of drug use. This paper reviews policies regulating the supply of drugs, particularly licensing and reimbursement controls, price and profit regulation. Price and profit controls contain few incentives for improving cost effective use of drugs, and focus on cost containment and profitability of domestic industry. Carefully monitored economic evaluation could lead to improvements in efficiency and benefits to patients and the health care system.  相似文献   

3.
4.
Disturbance events vary in intensity, size, and frequency, but few opportunities exist to study those that are extreme on more than one of these gradients. This article characterizes successional processes that occur following infrequent disturbance events that are exceptional in their great intensity or large size. The spatial variability in disturbance intensity within large, infrequent disturbances (LIDs) often leads to a heterogeneous pattern of surviving organisms. These surviving organisms dictate much of the initial successional pattern on large disturbances where the opportunities for seeds to disperse into the middle of the disturbance are limited. The traditional distinction between primary and secondary succession is insufficient to capture the tremendous variability in succession following LIDs. Disturbance size influences succession where long-distance colonization by propagules is important. Observations from LIDs suggest the following interrelated hypotheses about trends in succession with increasing distance from seed sources when disturbanceintensity is high: (a) initial densities of organisms will be lower; (b) nucleation processes, in which recovering patches serve as foci for additional colonization and expand spatially, will be more important; (c) competitive sorting will be less important relative to chance arrival in determination of community composition, and (d) community composition will be initially less predictable; and (e) the rate of recovery of community composition will be slower. Prediction of succession following LIDs without considering contingencies such as the abundance, types, and spatial distribution of residuals, and distance to seed sources is likely to be unsuccessful for large portions of the landscape. Abundance and spatial arrangement of survivors and arrival patterns of propagules may be the pivotal factors determining how succession differs between intense disturbances of large and small extent. Received 14 July 1998; accepted 18 September 1998  相似文献   

5.
6.
M Korcok 《CMAJ》1988,138(8):749-751
The case records of all patients admitted involuntarily to the psychiatric unit of a teaching general hospital between May 1, 1985, and Apr. 30, 1986, were examined to assess the criteria used for admission in relation to several patient characteristics. Of the 55 patients 42 were admitted under the terms of form 1 (application for psychiatric assessment) and 13 under the terms of form 3 (certificate of involuntary admission). All of the former patients and 70% of the latter were admitted under the criteria for dangerousness; however, one-third of these patients had failed to show any evidence of violent or suicidal behaviour. Most of the patients admitted because of their dangerousness had a nonpsychotic disorder, whereas 83% of those admitted because of lack of competence had a psychotic disorder. These findings are discussed in relation to the criteria for involuntary admission in the 1980 Mental Health Act of Ontario. The difficulties encountered in the admission process by physicians appear to be the result of a lack of clinical considerations and a predominant emphasis on dangerousness.  相似文献   

7.
A sample of 106 senior house officers who had graduated from Nottingham University in 1987 was surveyed about their experience of and need for careers guidance, performance appraisal, and stress counselling. Of the 80 who replied, a quarter had received no careers guidance and a quarter no feedback about their work performance. Many reported having had difficulties in their post, but few had received help from senior staff or their consultant. The perceived needs for counselling were considerable. Careers counselling was thought to be essential in the preregistration year by all of the doctors and in senior house officer posts by three quarters. Nearly all would have chosen regular appraisal and nearly half wanted counselling for particular difficulties. Doctors in the training grades clearly believed that they needed counselling, but in most cases they did not receive it.  相似文献   

8.
9.
Our aim was to explore and compare the job satisfaction between family physicians and hospital specialists in Split, Croatia. The survey was carried out in 2005 and 2006. A validated questionnaire was composed of two parts: 92 statements and questions about job satisfaction in the form of a Lickert scale (range 1-5) and eight questions concerning demographic issues. The questionnaire was completed and returned by 165 hospital specialists from the University Hospital and by 131 family physicians from the Split County. Response rate for family physicians was 39.81% and 41.46% for hospital specialists. Hospital doctors were divided in two groups: internal and surgical. There were no significant differences between family physicians and hospital specialists in total job satisfaction (F = 1.02; p = 0.41). Family physicians were more satisfied with their workplace conditions than internal medicine specialists (19.37 +/- 4.23 vs. 17.37 +/- 4.59; F = 5.93; p = 0.003), and less satisfied with the possibilities for postgraduate training than surgeons (5.27 +/- 1.90 vs. 6.59 +/- 2.07; F = 9.26; p < 0.001). Global job satisfaction was rather low but does not differ between the three medical groups. Disparities were observed in some segments (opportunity for further training and academic advancement, vacation, and salary). The reason for the family physician's relative satisfaction may be due to stable working conditions, independence in organizing work schedules and personal responsibility.  相似文献   

10.
11.
12.
Peters  Robert H. 《Hydrobiologia》1992,(1):435-455
Over the years, models and concepts developed to explain the behaviour of lake plankton have been generalized and extended to most parts of the limnetic community. This development has now fused with parallel research programs into stream and marine benthos and fish, to yield an imposing literature dealing with complex interactions in aquatic communities. Although the size of this literature has grown, its basic elements, i.e. the allometries of organismal capacity and environmental opportunity, remain those associated with the seminal size efficiency hypothesis. Unfortunately, the difficulties that eventually buried that hypothesis in a welter of detail and special cases were not resolved, so the newer, broader concepts associated with complex interactions remain difficult or impossible to test. Those concepts are so subjective, poorly defined, and variably interpreted that they are more effective in explaining our observations after the fact than in predicting them before-hand. Despite predictive failure, such explanatory models have achieved wide acceptance. Once accepted as substitutes for predictive theory, they mire the advance of science by hiding its deficiencies. One solution to this cloying complexity is insistence that the theories of ecology specify simple, observable response variables so that theories may be evaluated by their predictive power. Components of a general refuge concept illustrate the point. This policy has implications for environmental science well beyond the confines of plankton ecology.Dedicated to Dr Karl Banse, School of Oceanography, University of Washington on his 60th Birthday.  相似文献   

13.
J Berger 《CMAJ》1994,150(3):325-326
  相似文献   

14.
A large study of general practitioners in Manchester showed that women doctors were younger than men doctors, and few were single handed or worked in deprived inner city areas. They had closely similar patterns of care to their male colleagues, and although they worked slightly fewer hours in surgery, they had almost identical consultation times per patient. Women general practitioners were less active in politics and education than men.  相似文献   

15.
16.
17.
The discovery of human embryonic stem cells has pointed to the potential use of these cells in developing new approaches to therapy for many major human diseases. While there is general agreement that such applications are possible and will require a great deal of additional basic and preclinical research, some discussions of the therapeutic applications of human embryonic stem cells have been characterized by the kinds of exaggerations and elevated expectations that characterized the field of human gene therapy a decade ago. In the case of gene therapy, public perception of and confidence in the field were damaged by the hype. Most unfortunate of all, the hopes of patients and their advocates were disappointed. The eventual success of a gene therapy approach, albeit one still plagued by serious adverse events, has come through scientific advance and careful clinical application. The probable eventual use of human embryonic stem cells for therapy of human disease will also require thorough basic and clinical research, but that goal is endangered by the current level of inaccurate representations and undeliverable promises.  相似文献   

18.
19.
20.
Silks are protein fibers with remarkable mechanical properties. The discovery of the structural features that govern these properties is a challenge for biochemistry and structural biology. This review summarizes the results of the biochemistry of silk proteins as well as the knowledge of the molecular biology of the respective genes. In addition, an overview is presented on the efforts to produce recombinant silk proteins by biotechnological techniques.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号