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51.
The impact of trauma is a major public health challenge which is likely to escalate in the early 21st century. A systematic approach to this problem is required. This review explains the conceptual framework that defines a trauma system, gives a brief historical perspective and describes some of the essential elements of the system which should make a difference to patient outcome. Emergency physicians are well placed to play a leading role in the development and implementation of trauma systems.  相似文献   
52.
微创内固定系统治疗复杂股骨转子部骨折的初步报告   总被引:16,自引:10,他引:6  
目的探讨微创内固定系统(LISS)治疗复杂股骨转子部骨折的可行性、手术技术及指征,并总结其近期临床治疗效果。方法自2005年6月~2006年5月,应用LISS治疗复杂股骨转子部骨折12例。骨折采用AO分类法,其中转子间骨折5例:31-A2.2型2例,31-A2.3型2例,31-A3.3型1例;转子下骨折7例:32-A3.1型1例,32-B1.1型3例,32-B2.1型1例,32-B3.1型2例。记录手术时间、术中出血量、术后住院时间,术后观察有无感染、下肢深静脉血栓、心肺疾患、应激性溃疡等并发症。术后1、2、3、6、12个月时常规随访。结果手术时间50~90 min,平均65 min;出血量50~400 mL,平均142 mL,术后住院时间6~15 d,平均9.3 d。无死亡病例。所有患者均未出现切口感染、下肢深静脉血栓、术后心肺疾患、应激性溃疡等并发症。12例均获得3~14个月(平均7.2个月)随访。10例在术后3个月复查骨折时达到临床愈合,1例假体周围骨折术后4个月、1例病理性骨折术后6个月达到临床愈合。所有患者在最后一次随访时均无骨折再移位、髋内翻畸形、内固定切出、内固定失败及股骨头坏死。结论微创反向使用股骨LISS从生物力学和解剖结构上都能满足股骨近端骨折内固定要求,并具有创伤小、操作简便、固定可靠、安全性高、并发症少的特点,尤其适用于老年人合并内科疾病、骨质疏松较重的转子间骨折及复杂的股骨近端骨折。熟练掌握间接复位技术,正确放置A孔导针,避免过早负重是手术成功的关键。  相似文献   
53.
Hepatocyte isolation from pig livers after warm ischaemic injury   总被引:9,自引:0,他引:9  
Abstract Hepatocyte cultures have been used extensively for a wide variety of physiological, pharmacological and experimental studies. The warm ischaemic period before isolation is kept to a minimum to achieve a high yield of cells isolated and a good viability for culture. We have recently introduced a new concept of liver resuscitation after warm ischaemia that is based on a 3-h reperfusion period with an improved perfusate and simultaneous dialysis. In this study, we applied the new technique for hepatocyte isolation from livers subjected to 80 min of complete ischaemia at 37 °C. Cell yield was improved by a resuscitating perfusion from 58% to 73% and viability from 39% to 76%.  相似文献   
54.
55.
OBJECTIVE: The GRIF automated feedback system produces real-time comments on the appropriateness of diagnostic tests ordered by general practitioners (GPs) based on recommendations from accepted national and regional practice guidelines. We investigated the experiences of GPs with this system and, more specifically, with the recommendations produced by the system as well as their views on using this system in daily practice. SETTING: We tested the GRIF system in an experiment in a laboratory setting and in a daily practice trial. STUDY PARTICIPANTS: General practitioners. INTERVENTION: In the laboratory experiment, GPs used the GRIF system to assess the appropriateness of 30 request forms. Each of the GPs was confronted with requests they had submitted to the diagnostic unit of the hospital in the past. In the field trial, the GRIF system was applied during patient consultations for 1 year. MAIN OUTCOME MEASURES: We measured GPs' satisfaction with the system using a questionnaire, and also conducted group discussions (in the laboratory experiment) and in-depth interviews (in the field trial) to elicit GPs' opinions of and experiences with the system. In addition, we explored GPs' reasons for not accepting the comments offered by the GRIF system. RESULTS: The results show that the GPs in the laboratory experiment had more positive attitudes towards the system compared with participants in the field trial. All discussion groups and most of the GPs in the field trial regarded receiving the immediate feedback during the test ordering process as an important advantage. The most frequently mentioned reason to reject the recommendation was disagreement with the content and/or the recommendations in the practice guidelines. CONCLUSION: Apart from securing agreement on guideline content, a prerequisite for using GRIF in daily practice on a large scale is that more attention is paid to promotion of the guidelines and their adoption, and stimulation of a positive attitude towards the practice guidelines among the users.  相似文献   
56.
To assess the effect of stimulus correlated motion on the appearance of functional magnetic resonance images, conventional visual and motor protocols were each performed by four normal volunteers and an image co-registration technique was used to retrospectively monitor subject motion. In three studies synthetic data sets were constructed from single baseline images using the positional information obtained from the co-registration procedure. Cumulative difference images were then created from both the synthetic and functional image sets. Stimulus correlated motion was detected in all eight studies and the synthetic cumulative difference images showed striking similarities to the equivalent functional images in each case.  相似文献   
57.
应用修正正交分段线性函数的时滞和反向特性,推导出求解时滞系统和卷积的公式。数字仿真表明,它具有计算简单,精度高的优点。  相似文献   
58.
The aims of this study were (1) to elicit the users' responses to four electronic head-mounted devices (Jordy, Flipperport, Maxport and NuVision) and (2) to correlate users' opinion with performance. Ten patients with early onset macular disease (EOMD) and 10 with age-related macular disease (AMD) used these electronic vision enhancement systems (EVESs) for a variety of visual tasks. A questionnaire designed in-house and a modified VF-14 were used to evaluate the responses. Following initial experience of the devices in the laboratory, every patient took home two of the four devices for 1 week each. Responses were re-evaluated after this period of home loan. No single EVES stood out as the strong preference for all aspects evaluated. In the laboratory-based appraisal, Flipperport typically received the best overall ratings and highest score for image quality and ability to magnify, but after home loan there was no significant difference between devices. Comfort of device, although important, was not predictive of rating once magnification had been taken into account. For actual performance, a threshold effect was seen whereby ratings increased as reading speed improved up to 60 words per minute. Newly diagnosed patients responded most positively to EVESs, but otherwise users' opinion could not be predicted by age, gender, diagnosis or previous CCTV experience. User feedback is essential in our quest to understand the benefits and shortcoming of EVESs. Such information should help guide both prescribing and future development of low vision devices.  相似文献   
59.
60.
LISS钢板治疗股骨远端粉碎骨折的疗效分析   总被引:1,自引:0,他引:1  
目的探讨应用微创固定系统LISS钢板治疗股骨远端粉碎骨折的临床疗效。方法采用LISS钢板治疗股骨远端粉碎骨折26例。结果所有患者获得10—28个月随访,切口Ⅰ期甲类愈合,骨折全部愈合,X线复查骨折对位、对线良好,未发生感染,无内固定钢板、螺钉脱出、断裂等发生。疗效评价采用Kolmert评定标准:优A3型10例,C2型3例;良A3型2例,C2型1例,C3型5例:可C2型2例,C3型2例;差C3型1例。结论采用微刨固定系统LISS钢板治疗股骨远端粉碎骨折,是一种有效的内固定方法,具有操作简便、创伤小、疗效肯定等优点,为术后早期功能锻炼提供保证。  相似文献   
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