首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   28055篇
  免费   2597篇
  国内免费   43篇
耳鼻咽喉   302篇
儿科学   1089篇
妇产科学   585篇
基础医学   3589篇
口腔科学   431篇
临床医学   3506篇
内科学   4754篇
皮肤病学   510篇
神经病学   2797篇
特种医学   798篇
外国民族医学   1篇
外科学   3986篇
综合类   633篇
一般理论   23篇
预防医学   3400篇
眼科学   432篇
药学   2075篇
中国医学   44篇
肿瘤学   1740篇
  2023年   212篇
  2022年   289篇
  2021年   788篇
  2020年   436篇
  2019年   751篇
  2018年   880篇
  2017年   617篇
  2016年   604篇
  2015年   683篇
  2014年   937篇
  2013年   1323篇
  2012年   1896篇
  2011年   1950篇
  2010年   1080篇
  2009年   949篇
  2008年   1520篇
  2007年   1524篇
  2006年   1460篇
  2005年   1436篇
  2004年   1296篇
  2003年   1229篇
  2002年   1176篇
  2001年   647篇
  2000年   576篇
  1999年   488篇
  1998年   242篇
  1997年   200篇
  1996年   237篇
  1995年   175篇
  1994年   175篇
  1993年   151篇
  1992年   357篇
  1991年   348篇
  1990年   365篇
  1989年   328篇
  1988年   269篇
  1987年   285篇
  1986年   220篇
  1985年   247篇
  1984年   207篇
  1983年   161篇
  1982年   141篇
  1981年   106篇
  1980年   119篇
  1979年   169篇
  1978年   145篇
  1977年   109篇
  1976年   107篇
  1974年   128篇
  1973年   110篇
排序方式: 共有10000条查询结果,搜索用时 672 毫秒
91.
92.
INTRODUCTION: Health care workers have long been recognized as having a high risk of work-related assault. In response to a growing threat of violence in hospitals, California implemented the Hospital Security Act (AB508) in 1993. This study compares surveys of emergency nurses before and after implementation of AB508. METHODS: In 1990, the CAL/ENA surveyed emergency departments in California to enumerate violent events and describe security programs. Using the CAL/ENA membership directory, hospitals were resurveyed in 2000 to identify changes from the original survey. Surveys were mailed to the ED nurse manager or equivalent. Survey responses were anonymous. RESULTS: Most hospitals reported fewer violent episodes after the implementation of AB508. However, 32% of hospitals reported that 5 or more verbal threats occurred monthly, and 5% reported that 5 or more violent injuries occurred monthly. Overall, hospitals reported improvements in security programs. The most notable increase was in employee training, which rose from 34% to 95.6% of reporting hospitals. However, almost a quarter of hospitals reported not having general violence prevention policies, and many believed that security personnel were inadequate. DISCUSSION: Although results reported here cannot be directly attributed to AB508, the increase in security program components suggests that hospitals are responding positively to reduce violence. The high prevalence of threats and violent events reported indicates a persistent risk of violence against health care workers.  相似文献   
93.
94.
We studied the effects of nifedipine, a calcium antagonist, given intravenously and orally, on intraocular pressure in six normal volunteers. Nifedipine had no effect on intraocular pressure. Nifedipine is not contraindicated for the treatment of cardiovascular disease in glaucomatous patients and may have theoretical advantages in this situation, which are discussed.  相似文献   
95.
The management of patients through the use of evidence-based medicine has become the 'mantra' of medicine within many Western countries. Evidence-based medicine is aimed at providing the best objective, scientific care to all patients, and reducing as far as possible patients' risks of disease and complications from disease. Based on family physicians' discussions of the use of evidence-based recommendations for two cardiac diseases, this paper explores how subjectively-based trust enters into family physicians' decision to use evidence-based medicine. In addition, we show how trust influences physicians' work of recommending evidence-based medicine to patients, and physicians' perceptions of why patients follow recommendations aimed at risk reduction. We conclude that although much of the current discussion about evidence-based medicine assumes a 'rational' model of physician behaviour based on the application of the 'best objective scientific' results, subjectively-based perceptions of trust influence physician practices, and point to the need to understand the power of relational issues in influencing physician practices even when utilizing evidence-based knowledge.  相似文献   
96.
97.
Nonmotor symptoms (NMS) of Parkinson's disease (PD) are not well recognized in clinical practice, either in primary or in secondary care, and are frequently missed during routine consultations. There is no single instrument (questionnaire or scale) that enables a comprehensive assessment of the range of NMS in PD both for the identification of problems and for the measurement of outcome. Against this background, a multidisciplinary group of experts, including patient group representatives, has developed an NMS screening questionnaire comprising 30 items. This instrument does not provide an overall score of disability and is not a graded or rating instrument. Instead, it is a screening tool designed to draw attention to the presence of NMS and initiate further investigation. In this article, we present the results from an international pilot study assessing feasibility, validity, and acceptability of a nonmotor questionnaire (NMSQuest). Data from 123 PD patients and 96 controls were analyzed. NMS were highly significantly more prevalent in PD compared to controls (PD NMS, median = 9.0, mean = 9.5 vs. control NMS, median = 5.5, mean = 4.0; Mann-Whitney, Kruskal-Wallis, and t test, P < 0.0001), with PD patients reporting at least 10 different NMS on average per patient. In PD, NMS were highly significantly more prevalent across all disease stages and the number of symptoms correlated significantly with advancing disease and duration of disease. Furthermore, frequently, problems such as diplopia, dribbling, apathy, blues, taste and smell problems were never previously disclosed to the health professionals.  相似文献   
98.
General practitioners'' views on continuing medical education.   总被引:3,自引:2,他引:1       下载免费PDF全文
BACKGROUND. The 1990 contract for general practitioners altered the provision of continuing medical education. AIM. This study set out to examine doctors' experiences of postgraduate education before and after the contract and their preferences for the provision of postgraduate education. METHOD. In 1991 a structured questionnaire was sent to 1959 doctors registered on the database held by the west of Scotland postgraduate office. RESULTS. An 82% response rate was obtained. Eighty eight questionnaires had to be excluded. Of 1523 respondents, 74% were entitled to study leave under the terms of their practice agreement, an increase of 15% since the introduction of the contract. When attending courses 11% reported that they always employed a locum (32% occasionally). Those who did so were more likely to be general practitioners in rural areas than in urban or mixed areas. Almost all respondents (1485, 98%) had participated in postgraduate education since April 1990. Lectures remained popular (47% of respondents indicated it was their preferred or most preferred choice) while distance learning and practice based learning were least preferred. Evening meetings and afternoon meetings were the most popular, and Wednesday and Thursday were reported to be the most suitable days for educational meetings. CONCLUSION. Organizing education for a large number of people is difficult, but individuals' preferences and difficulties have emerged which must be taken into account when doing so. In terms of attendance, postgraduate education seems to have been a success although its value in influencing quality of care is more doubtful. Perhaps the development of personal education plans may make learning more useful and relevant.  相似文献   
99.
R Kelly 《Family practice》1992,9(1):104-108
The three papers reviewed for this issue deal with unrelated aspects of hypertension, illustrating the broad range of questions that still exist about optimal diagnosis and management. Physicians have for years been unsure about the efficacy, safety, and impact on morbidity of treating ISH. The result of these concerns has been that many, if not most patients with ISH never received treatment. The SHEP data are a powerful argument for routine treatment of ISH, which would represent a new standard of care for this condition. Only clinical experience and future trials will indicate whether treatment of ISH in the general population will be accompanied by the low incidence of side effects and morbidity observed in the more highly selected population of the SHEP trial. The study of Zeller et al. adds to the evidence that less is more, or at least the same, when it comes to treatment of hypertensive urgencies. The practice of oral 'loading' doses was not shown to improve therapeutic results. It is still not completely clear what criteria physicians should use in making a decision about inpatient parenteral therapy versus outpatient oral therapy. In patients with evidence of acute onset and end-organ injury, it is probably prudent to admit. In the absence of these risk factors, institution of an outpatient oral antihypertensive regimen can probably be accomplished with safety and at dramatically lower cost. The study of Koren et al. demonstrated a marked additional risk when LVH was present in hypertensive patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
We used immunohistochemical techniques to study the distribution of transforming growth factor-beta 1 (TGF-beta 1) and infiltrating lymphocytes and macrophages in human astrocytomas. Thirteen of 15 grade 4 astrocytomas (glioblastomas) showed staining with anti-TGF-beta 1 antibody, predominantly in proliferating endothelial complexes and surrounding small and medium-sized blood vessels. Brain tissue microscopically free of tumor cells (n = 8) and more differentiated astrocytomas of varying grade (1 to 3; n = 6) devoid of endothelial proliferation did not stain with anti-TGF-beta 1. Normal brain contained only rare lymphoreticular cells. The majority of astrocytomas studied, however, contained T lymphocytes and macrophages with smaller numbers of B lymphocytes. The lymphoreticular infiltrates were concentrated primarily in close proximity to blood vessels. Within an individual tumor perivascular regions staining for TGF-beta 1 never contained more than occasional T lymphocytes. Perivascular regions not staining for TGF-beta 1 frequently contained low to high numbers of T lymphocytes. The inverse relationship in the distribution of TGF-beta 1 and lymphocyte infiltrates is compatible with a functional relationship between this cytokine and an immune effector cell response to glioblastomas.  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