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   3753245篇
  免费   281514篇
  国内免费   35669篇
耳鼻咽喉   48217篇
儿科学   116615篇
妇产科学   98260篇
基础医学   520102篇
口腔科学   99919篇
临床医学   369507篇
内科学   708373篇
皮肤病学   81714篇
神经病学   299015篇
特种医学   141886篇
外国民族医学   1271篇
外科学   528584篇
综合类   140182篇
现状与发展   91篇
一般理论   1368篇
预防医学   297382篇
眼科学   86327篇
药学   287949篇
  438篇
中国医学   31476篇
肿瘤学   211752篇
  2021年   44016篇
  2020年   30405篇
  2019年   38714篇
  2018年   50174篇
  2017年   40721篇
  2016年   43895篇
  2015年   54180篇
  2014年   72677篇
  2013年   98276篇
  2012年   133885篇
  2011年   143631篇
  2010年   88571篇
  2009年   81147篇
  2008年   125562篇
  2007年   131440篇
  2006年   132226篇
  2005年   126990篇
  2004年   116216篇
  2003年   112166篇
  2002年   106673篇
  2001年   166114篇
  2000年   170239篇
  1999年   145021篇
  1998年   45104篇
  1997年   40462篇
  1996年   39496篇
  1995年   38046篇
  1994年   34822篇
  1993年   31822篇
  1992年   110218篇
  1991年   106424篇
  1990年   102972篇
  1989年   98931篇
  1988年   90763篇
  1987年   88871篇
  1986年   83713篇
  1985年   79814篇
  1984年   59587篇
  1983年   50837篇
  1982年   30259篇
  1979年   53029篇
  1978年   37643篇
  1977年   31560篇
  1976年   29801篇
  1975年   31379篇
  1974年   37444篇
  1973年   35845篇
  1972年   33501篇
  1971年   31161篇
  1970年   28847篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
通过病案举例,介绍大承气汤在中医脑病治疗中的使用技巧,说明大承气汤可以运用于出血性中风头痛、癫痫、失眠等多种脑病的治疗,疗效显著。大承气汤具有通腑泄热、祛邪外出的作用。对于六经辨证属阳明腑实证者,无论病种,皆可用大承气汤加味化裁。  相似文献   
102.
103.
Monitoring variations in the functioning of the autonomic nervous system may help personalize training of runners and provide more pronounced physiological adaptations and performance improvements. We systematically reviewed the scientific literature comparing physiological adaptations and/or improvements in performance following training based on responses of the autonomic nervous system (ie, changes in heart rate variability) and predefined training. PubMed, SPORTDiscus, and Web of Science were searched systematically in July 2019. Keywords related to endurance, running, autonomic nervous system, and training. Studies were included if they (a) involved interventions consisting predominantly of running training; (b) lasted at least 3 weeks; (c) reported pre- and post-intervention assessment of running performance and/or physiological parameters; (d) included an experimental group performing training adjusted continuously on the basis of alterations in HRV and a control group; and (e) involved healthy runners. Five studies involving six interventions and 166 participants fulfilled our inclusion criteria. Four HRV-based interventions reduced the amount of moderate- and/or high-intensity training significantly. In five interventions, improvements in performance parameters (3000 m, 5000 m, Loadmax, Tlim) were more pronounced following HRV-based training. Peak oxygen uptake () and submaximal running parameters (eg, LT1, LT2) improved following both HRV-based and predefined training, with no clear difference in the extent of improvement in . Submaximal running parameters tended to improve more following HRV-based training. Research findings to date have been limited and inconsistent. Both HRV-based and predefined training improve running performance and certain submaximal physiological adaptations, with effects of the former training tending to be greater.  相似文献   
104.
105.
106.
肿瘤免疫检查点抑制剂治疗为肿瘤患者带来生存获益的同时,也面临了许多挑战,例如免疫介导的肝毒性的发生。深入了解免疫检查点抑制剂治疗肿瘤过程中导致肝损伤的发生情况、可能机制、危险因素等,有助于更好地临床管理。  相似文献   
107.
Background: Lay belief systems about the malleability of human attributes have been shown to impact behavior change in multiple domains. Addiction mindset—i.e., beliefs about the permanence (vs. malleability) of addiction — may affect cigarette smokers’ ability to quit, but this has never been examined. Objectives: The aims of the present research were to develop a measure of addiction mindset (study 1) and examine its associations with various psychological aspects of quitting smoking (study 2). Methods: In Study 1, using factor analysis of current smokers’ and nonsmokers’ (n?=?600) responses to 22 items designed to measure addiction mindset, we developed a reliable six-item Addiction Mindset Scale (AMS). In Study 2, adult smokers (n?=?200) completed the AMS, and measures of a number of psychological processes related to smoking. Results: Higher scores on the AMS, indicative of the belief that addiction is malleable (referred to as a growth mindset), were positively and significantly associated with greater motivation to quit, greater commitment to quitting, greater self-efficacy to abstain, less attribution of failure to lack of ability to change addiction, and fewer self-reported barriers to cessation (all p’s < .05). Conclusions: The results of this study show a relationship between the beliefs about the permanence of addiction and psychological processes relevant to quitting smoking. The findings underscore the potential of future research exploring how addiction mindsets relate to successful smoking cessation as well as other types of addictive behavior and how they can be applied to change people’s behavior.  相似文献   
108.
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
109.

Purpose

Endovascular treatment with mechanical thrombectomy devices demonstrated high recanalization rates but functional outcome did not correlate with high rates of recanalization obtained. Patient selection prior to the endovascular treatment is very important in the final outcome of the patient. The primary aim of our study was to evaluate the prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and Pons-Midbrain Index (PMI) scores in patients with Basilar Artery Occlusion (BAO) treated with successful angiographic recanalization after mechanical thrombectomy.

Methods

Retrospective single-center study including 18 patients between 2008 and 2013 who had acute basilar artery occlusion managed with endovascular treatment within 24 hours from symptoms onset and with successful angiographic recanalization. The patients were initially classified into two groups according to clinical outcome and mortality at 90 days. For analysis we also divided patients into groups based on pc-ASPECTS (≥8vs.< 8) and PMI (≥3vs.< 3) on non-contrast CT (NCCT) and CT Angiography Source Images (CTASI). Imaging data were correlated to clinical outcome and mortality rate.

Results

CTASI pc-ASPECTS, dichotomized at < 8 versus≥8, was associated with a favorable outcome (RR: 2.6; 95% CI: 1.3-5.2) and a reduced risk of death (RR: 6.5: 95% CI: 7.8-23.3). All patients that survived and were functionally independent had pc-ASPECTS score≥8. None of the 5 patients with CTASI pc-ASPECTS score less than 8 survived.

Conclusion

PC-ASPECTS on CTASI is helpful for predicting functional outcome after BAO recanalization with endovascular treatment. These results should be validated in a randomized controlled trial in order to decide whether or not to treat a patient with BAO.  相似文献   
110.
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