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991.
Background: Microscopic cerebral arterial air embolism (CAAE) occurs commonly during cardiac surgery and causes acute and chronic nonfocal neurologic dysfunction. Nevertheless, most neuroimaging studies do not detect brain injury after cardiac surgery. Using a rabbit model, the authors hypothesized they could detect and quantitate severe brain injury and infarction 24 h after microscopic CAAE using the vital stain triphenyltetrazolium chloride.

Methods: Experiments were conducted in methohexital anesthetized New Zealand white rabbits. Surgical shams (n = 5) underwent surgery but had no neurologic insult. Positive controls (n = 3) received 200 [micro sign]l/kg of intracarotid air. Other animals were randomized to receive either 50 [micro sign]l/kg intracarotid air, which produces microscopic CAAE (n = 18), or 300 [micro sign]l intracarotid saline (control, n = 18). Outcomes included somatosensory evoked potential amplitude at 90 min, neurologic impairment score at 4 and 24 h (0 [normal] to 99 [coma]), and percentage of nonstaining brain at 24 h using color-discrimination image analysis. Severely injured or infarcted brain does not stain with triphenyltetrazolium chloride.

Results: Surgical shams had little neurologic impairment and a small amount of nonstaining brain at 24 h (5.2 +/- 2.4%; mean +/- SD). Positive controls had profound neurologic impairment and large amounts of nonstaining brain (40-97%). Ninety-minute somatosensory evoked potential amplitude was less in animals receiving 50 [micro sign]l/kg air versus saline: 38 +/- 28% versus 102 +/- 32%, respectively, P < 1 x 10-7. Neurologic impairment scores were greater in animals receiving 50 [micro sign]l/kg air versus saline: at 4 h, 43 +/- 16 versus 23 +/- 9, P < 1 x 10-7; at 24 h, 24 +/- 12 versus 15 +/- 8, P = 0.013. Nevertheless, there was no difference between 50 [micro sign]l/kg air and saline in nonstaining brain: 5.5 +/- 2.9% versus 6.8 +/- 5.4%, P = 0.83.  相似文献   

992.
993.
Objectives:  Although preoperative preparation programs were once common, most children currently undergoing outpatient surgery are first exposed to the hospital on the day of the procedure. It is advocated that these outpatient children undergo the preparation just prior to surgery.
Aim:  To assess the amount of time that healthcare providers spend with children and families on the day of surgery in the preoperative area.
Materials and Methods:  The study used video infrastructure in the preoperative holding area of Yale New Haven Children's Hospital to record all interactions between children, families, and healthcare providers. Videotapes were coded to characterize and quantify behaviors of healthcare professionals.
Results:  On the day of surgery, healthcare providers spent medians of 2.75–4.81 min interacting with children and parents in the preoperative area. Families spent a median of 46.5 min in the preoperative area. Healthcare professionals spent the most time in medical talk (averages of 42.5–48.2% of time spent with family) and little time was spent in nonmedical talk (range of 6.2–6.9% of time spent with family). Anesthesiologists and surgeons spent 28% and 18% of the interview in talk to children; admitting nurses spent more of the interview talking to children (43%).
Conclusions:  Families interact with healthcare providers for only a small proportion of the time they spent in the preoperative area. This is likely to be a result of increased production pressure in the perioperative settings and has implications for providing preparation for surgery on the morning of the procedure.  相似文献   
994.
Mind the theory/practice gap in nursing   总被引:2,自引:0,他引:2  
The theory/practice gap is a recurrent theme in the nursing literature. Numerous suggestions have been made about how this gap may be narrowed or even closed. However, there appears to have been little attempt to date to examine the ways in which research conducted into the hidden curriculum, and philosophical analysis of the concepts involved, might inform our understanding of the reasons for the existence of the theory/practice gap. This paper attempts to utilize some of the contributions from these areas of research, and as a result will argue that, while narrowing of the theory/practice gap may be a realistic goal, any attempt to close it completely will be doomed to failure.  相似文献   
995.
The issues surrounding skill mix are often highly contentious and, not surprisingly, various interest groups either welcome or reject attempts to examine the different combinations of staff, qualified and unqualified, experienced and inexperienced, in relation to costs, outcomes and quality of nursing care. Despite the strong passions aroused by the debate, other factors, most notably demographic changes and the possible shortage of nurses, new demands on health care services and the call for more cost-effective use of resources, have kept skill mix foremost on the policy agenda. The review covers manpower planning, an area where considerable efforts have been made to determine the number but rarely the mix of nurses required to provide the necessary care for patients. In addition, previous work on staff turnover, and the possibility of substituting less qualified for more qualified staff, are examined in relation to cost-containment, recruitment and demography, and the creation of a new single level of nurse. These factors, along with the introduction of health care assistants, will have an important influence on the future shape and structure of nursing and, of course, the composition of the skills available. While calling for further work on skill mix, the review provides a timely reminder that the issues are complex and often highly political.  相似文献   
996.
Quality assurance (QA) is being hailed as a 'new frontier' of nursing. Its diffusion into nursing theory and practice in the United Kingdom is outlined. QA is not an alien import; favourable preconditions already existed. The systems-reasoning of the nursing process, which sprawned a plethora of models, each geared to the 'orderly' progression of stages, objectives and process, is resonant with the values and measurement techniques of QA. A major limitation of QA is that it downplays the organizational complexity of hospitals. Although QA is projected as being in the service of clients, its major impetus is concerned with professional self-defence, as regards other professions, the state and litigious clients. Further, QA enlisted by nursing strongly reproduces the ethos and logic of the dominant medical model; patients are 'objectified' as the technical products of production. The 'medical gaze' is now being joined with the 'nursing gaze'.  相似文献   
997.
Brain Impairment in Social Drinkers? No Cause for Concern   总被引:1,自引:0,他引:1  
Correlations between measures of alcohol consumption and cognitive test scores have been interpreted to reflect a chronic toxic effect of ethanol on brain function in light to moderate social drinkers. However, the data indicate that there is little support across research groups for any specific relationship and, at best, the effect of alcohol consumption accounts for only a small proportion of variance. Consideration of test validity suggests that the principal measure of ability used in this research is not capable of elucidating cerebral deficit. Further, the pattern of observed correlations is not consistent with the assumption that the putative effects of social drinking involve deficits less severe but similar in type to those seen in chronic alcoholics. Instead, an association between innate ability, demographic variables, and drinking behavior in the general population is the most parsimonious explanation of all the data.  相似文献   
998.
It is frequently suggested that younger adults are negative in their attitudes toward elderly people. There are also claims that such attitudes develop as a result of the socially constructed phenomenon of ageism. This paper briefly addresses the concept as it is presented in the literature and goes on to describe an attitudinal study which supports the existence of ageism. An Attitudes Toward the Elderly inventory was administered to secondary school pupils during their final 2 years of schooling, to student nurses at the very beginning of their training and to qualified nurses. It was found that the subjects did demonstrate negative attitudes and that there appeared to be a definite gender socialization influence, with females demonstrating less negative attitudes than males. Contrary to expectations, entry into nursing did not lead to more positive attitudes but had the converse effect. The influence of ageism and more specific professional socialization processes are suggested as explanations for these patterns. Implications for nursing and other occupational groups involved in caring for the elderly are discussed.  相似文献   
999.
In this paper, the consequences were there greater autonomy in nursing practice, are considered. Autonomous practice implies accountability which entails both personal and professional responsibility: a personal responsibility to endorse ethical conduct consistent with professional practice; and a professional responsibility to exercise discretionary powers to the ultimate benefit of the patient. In this context, discretionary responsibility implies: recognizing a patient's wants may not be consistent with a patient's needs; abstaining from collusion with noncompliant patients; supporting the patient's right to refuse treatment only after full psychological exploration; understanding the psychological ramifications of informed consent from a practitioner and recipient point of view; maintaining appropriate personal and professional boundaries; and fostering collegiate relationships with the medical fraternity grounded on egalitarian principles. The author provides a philosophical and psychological analysis of responsibility in an effort to achieve a deeper understanding of the relationship this has with the concepts of 'freedom' and 'accountability'.  相似文献   
1000.
INTRODUCTION: A wide variety of opinions exist about using paramedics on flight teams, most of which have not been substantiated by research findings. This study was conducted to explore the outcomes of patients transported by helicopter crews that consisted of either two nurses or a nurse and a paramedic. METHODS: Using data from the New York State Trauma Registry and prehospital care reports, a retrospective comparison was made between the outcomes of 1193 air medical patients transported either by crews consisting of two nurses (N/N) or a nurse and a paramedic (N/P). The sample included blunt and penetrating trauma patients with an Injury Severity Score greater than or equal to 9 and who were older than 16 years. RESULTS: The findings indicate the percentages of patients who lived, died, or were discharged home or to rehabilitation were similar for N/P and N/N groups. Using TRISS methodology and the Z statistic, no statistically significant difference was found in observed versus predicted mortality for both groups (P <.05). CONCLUSION: No significant difference existed in patient outcomes between N/P and N/N crews.  相似文献   
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