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   346742篇
  免费   24203篇
  国内免费   7957篇
耳鼻咽喉   4206篇
儿科学   9570篇
妇产科学   6562篇
基础医学   28282篇
口腔科学   8153篇
临床医学   37583篇
内科学   42954篇
皮肤病学   4635篇
神经病学   20245篇
特种医学   7952篇
外国民族医学   35篇
外科学   36516篇
综合类   52573篇
现状与发展   15篇
一般理论   31篇
预防医学   35119篇
眼科学   5358篇
药学   32456篇
  379篇
中国医学   32627篇
肿瘤学   13651篇
  2023年   5488篇
  2022年   8223篇
  2021年   13154篇
  2020年   12768篇
  2019年   18469篇
  2018年   16156篇
  2017年   13051篇
  2016年   10559篇
  2015年   9943篇
  2014年   20281篇
  2013年   21947篇
  2012年   18778篇
  2011年   20345篇
  2010年   16319篇
  2009年   14984篇
  2008年   14595篇
  2007年   15149篇
  2006年   13177篇
  2005年   11430篇
  2004年   9332篇
  2003年   8228篇
  2002年   6470篇
  2001年   5814篇
  2000年   4832篇
  1999年   4147篇
  1998年   3194篇
  1997年   3049篇
  1996年   2669篇
  1995年   2724篇
  1994年   2652篇
  1993年   2113篇
  1992年   2118篇
  1991年   1844篇
  1990年   1666篇
  1989年   1462篇
  1988年   1393篇
  1987年   1206篇
  1985年   3881篇
  1984年   4889篇
  1983年   3407篇
  1982年   3869篇
  1981年   3612篇
  1980年   3214篇
  1979年   2951篇
  1978年   2563篇
  1977年   1946篇
  1976年   2185篇
  1975年   1656篇
  1974年   1459篇
  1973年   1291篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
目的 以“中医体质辨识”为主题开展系统的可视化分析,探索中医体质辨识领域的发展现状、研究热点、发展趋势,为后续研究提供借鉴。方法 以中国知网(CNKI)数据库为数据源检索相关文献,并将所得数据文件导入CiteSpace软件,对作者、机构和关键词进行共现分析并得到相关知识图谱。结果 共纳入1099篇文献,通过CiteSpace共现分析找到中医体质辨识领域研究的高产机构、具有代表性的研究者以及高频关键词。研究发现各个研究者及机构缺乏沟通合作,研究热点主题有体质研究、治未病、健康管理、与现代生物医学相结合。结论 中医体质辨识领域的研究逐年增加,知识图谱揭示了中医体质辨识在健康管理、与现代生物医学相结合将是未来的研究趋势。  相似文献   
102.
顺铂(DDP)作为第一个被发现的金属抗癌药物,是目前最有潜力和应用最广泛的抗肿瘤药物。顺铂在宫颈癌的治疗中尤为重要,目前已被推荐为同步放化疗的首选药物。但随着广泛的使用,顺铂的耐药性逐渐显露出来,并成为限制临床疗效和部分患者肿瘤治疗进展的主要原因之一。顺铂的耐药机制复杂,发生环节较多,但具体耐药机制尚不明确,目前按照顺铂耐药发生的环节可分为:①顺铂在血液循环过程中产生耐药;②顺铂通过细胞膜的流入或流出产生耐药;③顺铂在胞质中产生耐药;④顺铂与DNA结合后产生耐药。本文综述了宫颈癌顺铂耐药可能发生的四个环节及克服耐药常用的手段,为提高顺铂对宫颈癌的疗效提供依据。  相似文献   
103.
The teaching and clinical practice of professor Yves Pélicier contributed to the international development of a psychiatry centered on the whole of the person in a humanist approach. The theoretical developments were marked by the authenticity of the practice of the therapist and its deep sense of the human being thus truly founding a School.  相似文献   
104.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons.  相似文献   
105.
目的 本文将通过网络药理学结合分子对接对温经汤治疗原发性痛经作用机制进行预测。方法 利用TCMSP、TCMID及BATMAN-TCM数据库,收集温经汤活性成分并预测其作用靶标。通过GeneCards数据库、OMIM数据库筛选原发性痛经的靶标,并运用R软件获取疾病交集靶标,绘制韦恩图。运用Cytoscape软件构建温经汤治疗原发性痛经的成分-靶标网络图,通过STRING数据库构建PPI靶标蛋白互作网络,并进行核心靶标的GO功能富集分析及KEGG通路富集分析。通过Autodock Vina软件对药物活性成分与疾病核心靶标进行分子对接验证。结果 筛选得到温经汤治疗原发性痛经的124个活性成分和31个药物-疾病共同靶标,并推断其作用机制可能与介导HIF-1、TNF、PI3K-Akt等105条信号通路相关。槲皮素、山柰酚、豆甾醇等活性成分与PTGS1、ESR1、PGR等核心靶标对接结果良好。结论 温经汤活性成分可能通过发挥镇痛、抗炎、调节激素水平、缓解平滑肌痉挛和改善缺氧状态等药理作用来治疗原发性痛经。  相似文献   
106.
107.
108.
109.
《Neuromodulation》2021,24(8):1317-1326
ObjectivesHow spinal cord stimulation (SCS) in its different modes suppresses pain is poorly understood. Mechanisms of action may reside locally in the spinal cord, but also involve a larger network including subcortical and cortical brain structures. Tonic, burst, and high-frequency modes of SCS can, in principle, entrain distinct temporal activity patterns in this network, but finally have to yield specific effects on pain suppression. Here, we employ high-density electroencephalography (EEG) and recently developed spatial filtering techniques to reduce SCS artifacts and to enhance EEG signals specifically related to neuromodulation by SCS.Materials and MethodsWe recorded high-density resting-state EEGs in patients suffering from pain of various etiologies under different modes of SCS. We established a pipeline for the robust spectral analysis of oscillatory brain activity during SCS, which includes spatial filtering for attenuation of pulse artifacts and enhancement of brain activity potentially modulated by SCS.ResultsIn sensor regions responsive to SCS, neuromodulation strongly reduced activity in the theta and low alpha range (6–10 Hz) in all SCS modes. Results were consistent in all patients, and in accordance with thalamocortical dysrhythmia hypothesis of pain. Only in the tonic mode showing paresthesia as side effect, SCS also consistently and strongly reduced high-gamma activity (>84 Hz).ConclusionsEEG spectral analysis combined with spatial filtering allows for a spatially and temporally specific assessment of SCS-related, neuromodulatory EEG activity, and may help to disentangle therapeutic and side effects of SCS.  相似文献   
110.
Localized gastric amyloidosis (LGA) is a rare disease characterized by abnormal extracellular deposition of amyloid protein restricted to the stomach and it is confirmed by positive results of Congo red staining. Over decades, only a few cases have been reported and studies or research focusing on it are few. Although LGA has a low incidence, patients may suffer a lot from it and require proper diagnosis and management. However, the pathology of LGA remains unknown and no overall review of LGA from its presentations to its prognosis has been published. Patients with LGA are often asymptomatic or manifest atypical symptoms, making it difficult to differentiate from other gastrointestinal diseases. Here, we report the case of a 70-year-old woman with LGA and provide an overview of case reports of LGA available to us. Based on that, we conclude current concepts of clinical manifestations, diagnosis, treatment, and prognosis of LGA, aiming at providing a detailed diagnostic procedure for clinicians and promoting the guidelines of LGA. In addition, a few advanced technologies applied in amyloidosis are also discussed in this review, aiming at providing clinicians with a reference of diagnostic process. With this review, we hope to raise awareness of LGA among the public and clinicians.  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