全文获取类型
收费全文 | 1302423篇 |
免费 | 87259篇 |
国内免费 | 9781篇 |
专业分类
耳鼻咽喉 | 16753篇 |
儿科学 | 39179篇 |
妇产科学 | 31475篇 |
基础医学 | 184115篇 |
口腔科学 | 32477篇 |
临床医学 | 117515篇 |
内科学 | 241415篇 |
皮肤病学 | 26344篇 |
神经病学 | 97322篇 |
特种医学 | 51830篇 |
外国民族医学 | 266篇 |
外科学 | 192167篇 |
综合类 | 45772篇 |
现状与发展 | 30篇 |
一般理论 | 275篇 |
预防医学 | 92807篇 |
眼科学 | 28825篇 |
药学 | 106635篇 |
128篇 | |
中国医学 | 10606篇 |
肿瘤学 | 83527篇 |
出版年
2021年 | 14677篇 |
2020年 | 10183篇 |
2019年 | 12387篇 |
2018年 | 26578篇 |
2017年 | 21933篇 |
2016年 | 24574篇 |
2015年 | 17802篇 |
2014年 | 23147篇 |
2013年 | 29793篇 |
2012年 | 43743篇 |
2011年 | 52572篇 |
2010年 | 34081篇 |
2009年 | 29574篇 |
2008年 | 47172篇 |
2007年 | 51594篇 |
2006年 | 39651篇 |
2005年 | 39132篇 |
2004年 | 36894篇 |
2003年 | 36834篇 |
2002年 | 33877篇 |
2001年 | 63445篇 |
2000年 | 64611篇 |
1999年 | 53536篇 |
1998年 | 14214篇 |
1997年 | 12948篇 |
1996年 | 12356篇 |
1995年 | 11622篇 |
1994年 | 10544篇 |
1993年 | 9710篇 |
1992年 | 38758篇 |
1991年 | 37188篇 |
1990年 | 36574篇 |
1989年 | 35034篇 |
1988年 | 31549篇 |
1987年 | 30605篇 |
1986年 | 28772篇 |
1985年 | 26928篇 |
1984年 | 19563篇 |
1983年 | 16438篇 |
1982年 | 9142篇 |
1979年 | 17290篇 |
1978年 | 11627篇 |
1977年 | 10414篇 |
1975年 | 10177篇 |
1974年 | 11814篇 |
1973年 | 11390篇 |
1972年 | 10844篇 |
1971年 | 10202篇 |
1970年 | 9374篇 |
1969年 | 9064篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
目的 总结国产封堵器经皮和经胸途径治疗先天性心脏病的临床疗效。方法 回顾性分析我院2013年1月至2017年12月在X线透视下或单纯超声心动图引导下采用经皮穿刺股静脉或股动静脉法,或者食管超声心动图监测下经胸小切口行先天性心脏病封堵1186例,其中经皮X线下封堵1081例、经皮单纯超声引导下封堵42例、经胸封堵63例;其中动脉导管未闭( patent ductus arteriole,PDA)426例、房间隔缺损(atrial septal defect,ASD)363例、室间隔缺损(ventricular septal defect,VSD)348例、卵圆孔未闭11例、房间隔缺损合并室间隔缺损9例、房间隔缺损合并动脉导管未闭6例、房间隔缺损合并肺动脉瓣狭窄(pulmonary stenosis,PS)12例、动脉导管未闭合并肺动脉瓣狭窄8例、主肺动脉侧支封堵3例[经胸封堵66例改为63例,PDA443例改为426例]。结果 全组病例成功率98.2%(1165/1186),无死亡病例。随访1~36个月,术后第1、3、6、12个月及术后每年常规行超声心动图及心电图检查。术后第1、6、12个月的随访率分别为 92.9%(1102/1186)、84.1%(998/1186)、70.5%(836/1186)。超声心动图提示少量残余分流(<3 mm)18例;三尖瓣少量反流33例,中量反流5例;主动脉瓣轻度反流5例,中度反流1例;心律失常Ⅲ°房室传导阻滞(Avionics Bulletin,AVB[房室传导阻滞(Avionics Bulletin,AVB)])1 例,Ⅱ°AVB 3例,完全性左束支3例,交界性心动过速3例,交界性逸搏2例。结论 国产封堵器在先天性心脏病封堵治疗中具有成功率高、创伤小、并发症低、操作容易、疗效确切、恢复快等特点,是治疗先天性心脏病的理想方法。 相似文献
73.
Hyo-Kon Kim Sung-Han Ha Gi-Jun Lee Sun-O Yu Jung-Rae Kim 《Clinics in Orthopedic Surgery》2015,7(3):414-417
Synovial chondromatosis is a rare lesion in the wrist, but some cases in the distal radioulnar joint have been reported and previous case reports emphasize joint calcifications, shown on preoperative plain radiographs. We report an extremely uncommon case of synovial chondromatosis in the pisotriquetral joint, in which radiographs and magnetic resonance imaging did not demonstrate apparent calcified bodies. In our case, for the accurate diagnosis and treatment, surgical exploration of the joint and synovectomy with removal of loose bodies was performed. 相似文献
74.
75.
76.
Dalton Luiz Schiessel Ricardo K. Yamazaki Marcelo Kryczyk Isabela Coelho de Castro Adriana A. Yamaguchi Danielle C. T. Pequito 《Nutrition and cancer》2016,68(8):1369-1380
Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO. 相似文献
77.
Rebecca L. King Albert C. Yan Debora R. Sekiguchi John K. Choi 《Journal of cutaneous pathology》2015,42(12):1012-1017
Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin. 相似文献
78.
M. R. D. Maslin S. K. Lloyd S. Rutherford S. Freeman A. King D. R. Moore K. J. Munro 《Journal of the Association for Research in Otolaryngology》2015,16(5):631-640
Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis. 相似文献
79.
Xiaoyan Lu Isabelle R. Miousse Sandra V. Pirela Jodene K. Moore Stepan Melnyk 《Nanotoxicology》2016,10(5):629-639
Evidence continues to grow on potential environmental health hazards associated with engineered nanomaterials (ENMs). While the geno- and cytotoxic effects of ENMs have been investigated, their potential to target the epigenome remains largely unknown. The aim of this study is two-fold: 1) determining whether or not industry relevant ENMs can affect the epigenome in vivo and 2) validating a recently developed in vitro epigenetic screening platform for inhaled ENMs. Laser printer-emitted engineered nanoparticles (PEPs) released from nano-enabled toners during consumer use and copper oxide (CuO) were chosen since these particles induced significant epigenetic changes in a recent in vitro companion study. In this study, the epigenetic alterations in lung tissue, alveolar macrophages and peripheral blood from intratracheally instilled mice were evaluated. The methylation of global DNA and transposable elements (TEs), the expression of the DNA methylation machinery and TEs, in addition to general toxicological effects in the lung were assessed. CuO exhibited higher cell-damaging potential to the lung, while PEPs showed a greater ability to target the epigenome. Alterations in the methylation status of global DNA and TEs, and expression of TEs and DNA machinery in mouse lung were observed after exposure to CuO and PEPs. Additionally, epigenetic changes were detected in the peripheral blood after PEPs exposure. Altogether, CuO and PEPs can induce epigenetic alterations in a mouse experimental model, which in turn confirms that the recently developed in vitro epigenetic platform using macrophage and epithelial cell lines can be successfully utilized in the epigenetic screening of ENMs. 相似文献
80.