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61.
In employee relations, perception is as important as reality. What the employee perceives is generally what the employee believes and acts on. Employee perceptions are shaped by many factors, prominent among them organizational roles, supervisory styles, and communication styles. Employee perceptions cannot be ignored, even when they are known to be incorrect, because they are factual to the employees. Further, perceptions can be controlled to a considerable extent through effective supervision. The supervisor needs to become aware of the power of perception, learn what circumstances are likely to cause incorrect perceptions, learn how to manage employee perceptions to the extent possible, and always approach perception as the perceiver's reality.  相似文献   
62.
Those employees called professionals are in some ways little different from any other employees but in a few ways can be anywhere from subtly to dramatically different. As others, professionals are motivated by a unique mix of needs that can be used to gain insight into the appropriate supervisory techniques to apply. Different approaches to supervision are sometimes called for in the face of professionals' advantages, specifically their generally greater education and their external mobility owing to the presence of specific expertise used in other organizations, and their resulting loyalty to an occupation that frequently outweighs loyalty to an organization. The professional in short supply enjoys unique advantages that provide additional challenges for supervision. The conclusion eventually reached concerning supervising professionals is that honest, people-centered management is the key to success.  相似文献   
63.
OBJECTIVE--To determine whether particular sociodemographic characteristics of patients with stable angina affected their general practitioners' (GPs') decisions to refer them for revascularisation assessment. DESIGN--Postal questionnaire survey. SETTING--Collaborative survey by the departments of public health medicine in each of the four health boards in Northern Ireland, serving a total population of 1.5 million. SUBJECTS--All (962) GPs. MAIN MEASURES--The relation between GPs' referral decisions and patients' age, sex, employment status, home circumstances, smoking habits, and obesity. RESULTS--541 GPs replied (response rate 56%). Most were "neutral" towards a patient's sex (428, 79%), weight (331, 61%), smoking habit (302, 56%), employment status (431, 80%), and home circumstances (408, 75%) in making decisions about referral. In assigning priority for surgery most were neutral towards the patient's sex (459, 85%), employment status (378, 70%), and home circumstances (295, 55%). However, most GPs (518, 95%) said that younger patients were more likely to be referred, and a significant minority were less likely to refer patients who smoked (202, 37%) and obese patients (175, 32%) and more likely to refer employed patients (97, 18%) and those with dependents (117, 22%) (compared with patients with otherwise comparable clinical characteristics); these views paralleled the priority which GPs assigned these groups. The stated likelihood of referral of young patients was independent of the GPs' belief in ability to benefit from revascularisation, but propensity to refer and perception of benefit were significantly associated for all other patient characteristics. CONCLUSION--GPs' weighting of certain characteristics in reaching decisions about referral for angiography is not uniform and may contribute to unequal access to revascularisation services for certain patient groups.  相似文献   
64.
A simple model is described for calculating the electrostatic energy of lipid domains at the air-water interface, taking account of dipole-dipole repulsions between the lipid molecules themselves, as well as interactions between the molecular dipoles and image dipoles in the subphase. The model assumes that the molecular dipoles within the monolayer arise from the terminal methyl groups of the hydrophobic hydrocarbon chains of the lipid molecules, and that on average they are oriented perpendicular to the plane of the monolayer. With this model the role of the subphase is to enhance rather than suppress the effects of dipole-dipole repulsions.  相似文献   
65.
OBJECTIVE--To determine the perceptions of general practitioners (GPs) about the benefits of coronary artery bypass surgery, in terms of gains in life expectancy, for different groups of patients. DESIGN--A questionnaire survey of all GPs in Northern Ireland. SETTING--A survey conducted collaboratively by the departments of public health medicine in each of the four health boards in the province, serving a total population of 1.5 million. MAIN OUTCOME MEASURES--The median and mean gain in life expectancy perceived by groups of doctors for smoking and non-smoking male and female 55 year old patients. The percentage of 50 year old and 70 year old non-smoking patients considered likely to have their lives extended with bypass surgery. Differences were assessed using the Mann-Whitney U test for unpaired samples and the Wilcoxon signed rank tests for paired. RESULTS--541 GPs replied (response rate 56%). The median (and mean) perceived gain in life expectancy after cardiac surgery for non-smoking 55 year old subjects was 120 (104) months for men and 120 (112) months for women (z = 6.42; P < 0.0001; Wilcoxon signed rank test). For male and female smokers of the same age, the perceived gains were 48 (47) and 60 (52) months respectively (z = 6.72; P < 0.0001; Wilcoxon signed ranks test), both figures being significantly different than for non-smokers. The median (and mean) percentage of patients that the doctors considered would have their lives extended by bypass surgery was 70 (64) of every 100 "young" patients and 40 (42) of every 100 "old" patients, (z = 16.2; P < 0.0001). CONCLUSIONS--These results point to a significant overestimation of the benefits of coronary artery bypass surgery by GPs in Northern Ireland and to a need to develop guidelines for referral.  相似文献   
66.
67.
Screening methods for thyroid hormone disruptors   总被引:15,自引:0,他引:15  
The U.S. Congress has passed legislation requiring the EPA to implement screening tests for identifying endocrine-disrupting chemicals. A series of workshops was sponsored by the EPA, the Chemical Manufacturers Association, and the World Wildlife Fund; one workshop focused on screens for chemicals that alter thyroid hormone function and homeostasis. Participants at this meeting identified and examined methods to detect alterations in thyroid hormone synthesis, transport, and catabolism. In addition, some methods to detect chemicals that bind to the thyroid hormone receptors acting as either agonists or antagonists were also identified. Screening methods used in mammals as well as other vertebrate classes were examined. There was a general consensus that all known chemicals which interfere with thyroid hormone function and homeostasis act by either inhibiting synthesis, altering serum transport proteins, or by increasing catabolism of thyroid hormones. There are no direct data to support the assertion that certain environmental chemicals bind and activate the thyroid hormone receptors; further research is indicated. In light of this, screening methods should reflect known mechanisms of action. Most methods examined, albeit useful for mechanistic studies, were thought to be too specific and therefore would not be applicable for broad-based screening. Determination of serum thyroid hormone concentrations following chemical exposure in rodents was thought to be a reasonable initial screen. Concurrent histologic evaluation of the thyroid would strengthen this screen. Similar methods in teleosts may be useful as screens, but would require indicators of tissue production of thyroid hormones. The use of tadpole metamorphosis as a screen may also be useful; however, this method requires validation and standardization prior to use as a broad-based screen.  相似文献   
68.
69.
The minute ventilation (VE) and carbon dioxide output (VCO&sub2;) adaptations to 12 weeks of cardiac rehabilitation were investigated in diagnosis-matched elderly patients (ELD) and younger patients (YNG). Thirty ELD (25 males, 5 females; age equals 69.2?+/-3.9 years) and 30 YNG (27 males, 3 females; age equals 48.3?+/-7.0 years) were exercise tested at program entry (T1) and completion (T2). Peak oxygen uptake (VO&sub2; peak) and ventilatory threshold (VT) (ml kg-1 min-1) were greater for YNG at both T1 and T2 (p is less than 0.01). Both ELD and YNG showed significant T1 to T2 improvements (p is less than 0.01) for VO&sub2; peak (21.1% and 23.4%) and VT (20.1% and 12.4%). The VE/VCO&sub2; ratio was greater (p is less than 0.01) for ELD but approached YNG values after training. The VCO&sub2;/VO&sub2; slope showed a greater T1 to T2 reduction in ELD (12.4% vs 3.4%). There was no relationship (r(2) equals 0.15; NS) between the percentage change in VO&sub2; peak and VE/VCO&sub2; indicating unrelated mechanisms of improvement. We conclude that ELD showed similar improvements in VO&sub2; peak but greater improvements in their ventilatory tolerance for submaximal exercise. These changes indicate improvements in aging-enhanced exercise ventilation, are important for performance of normal activities of daily living, and would have been undetectable without gas exchange analysis.  相似文献   
70.
As health care comes under mounting pressure to reduce costs, organizations are restructuring. Delivery systems are changing. As layoffs occur and changes are made in numbers and responsibilities of managers, supervisors find themselves in dramatically changing roles. Job security has become as illusory in health care as elsewhere. Morale among health workers is sagging, and motivational concerns are increasing. The supervisor has been put in the position of having to do more with less and to do it in the face of demoralized forces. The paradigms that were once operational are shifting, and the evolving role of the health care supervisor suggests that a completely new set of paradigms is taking over that suggests the supervisor's future security lies in the ability to learn new things and to shift and change with the environment.  相似文献   
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