全文获取类型
收费全文 | 27364篇 |
免费 | 2351篇 |
国内免费 | 2045篇 |
专业分类
耳鼻咽喉 | 218篇 |
儿科学 | 254篇 |
妇产科学 | 243篇 |
基础医学 | 3178篇 |
口腔科学 | 424篇 |
临床医学 | 3598篇 |
内科学 | 3773篇 |
皮肤病学 | 173篇 |
神经病学 | 1363篇 |
特种医学 | 966篇 |
外国民族医学 | 19篇 |
外科学 | 3141篇 |
综合类 | 4649篇 |
现状与发展 | 5篇 |
一般理论 | 1篇 |
预防医学 | 1892篇 |
眼科学 | 676篇 |
药学 | 2934篇 |
33篇 | |
中国医学 | 1571篇 |
肿瘤学 | 2649篇 |
出版年
2025年 | 2篇 |
2024年 | 420篇 |
2023年 | 591篇 |
2022年 | 1167篇 |
2021年 | 1342篇 |
2020年 | 1122篇 |
2019年 | 957篇 |
2018年 | 925篇 |
2017年 | 831篇 |
2016年 | 822篇 |
2015年 | 1207篇 |
2014年 | 1470篇 |
2013年 | 1286篇 |
2012年 | 1806篇 |
2011年 | 2042篇 |
2010年 | 1316篇 |
2009年 | 1048篇 |
2008年 | 1360篇 |
2007年 | 1446篇 |
2006年 | 1339篇 |
2005年 | 1360篇 |
2004年 | 854篇 |
2003年 | 955篇 |
2002年 | 731篇 |
2001年 | 619篇 |
2000年 | 672篇 |
1999年 | 788篇 |
1998年 | 481篇 |
1997年 | 480篇 |
1996年 | 339篇 |
1995年 | 319篇 |
1994年 | 314篇 |
1993年 | 169篇 |
1992年 | 214篇 |
1991年 | 180篇 |
1990年 | 151篇 |
1989年 | 152篇 |
1988年 | 127篇 |
1987年 | 103篇 |
1986年 | 75篇 |
1985年 | 82篇 |
1984年 | 28篇 |
1983年 | 17篇 |
1982年 | 13篇 |
1981年 | 11篇 |
1980年 | 6篇 |
1979年 | 19篇 |
1974年 | 1篇 |
1929年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Long Wang Yisong lv Huixiang Yao Li Yin Jianhui Shang 《International journal of clinical and experimental pathology》2015,8(9):11503-11509
Background: Non-alcoholic fatty hepatitis (NASH) is highly prevalent, mitochondria damage is the main pathophysiological characteristic of NASH. However, treatment for mitochondria damage is rarely reported. Methods: NASH model was established in rats, the protective effects of curcumin were evaluated by histological observation; structure and function assessments of mitochondria; and apoptotic genes expression. Results: NASH rats treated with curcumin displayed relatively slight liver damage when compared with NASH livers. The average mitochondrial length and width of NASH (12.0 ± 3.2 and 5.1 ± 1.1 micrometers) were significantly longer than that of normal (6.2 ± 2.1 and 2.1 ± 1.5 micrometers) and NASH treated with curcumin (7.4 ± 1.2 and 3.2 ± 1.5 micrometers) rats. The average malondialdehyde (MDA) and 4-hydroxy nonyl alcohol (HNE) levels in liver homogenates of NASH rats (4.23 ± 0.22 and 19.23 ± 2.3 nmol/Ml) were significantly higher than these in normal (1.32 ± 0.12 and 3.52 ± 0.43 nmol/mL) and NASH treated with curcumin (1.74 ± 0.11 and 4.66 ± 0.99 nmol/mL) rats. The expression levels of CytC, Casp3 and Casp8 of the NASH livers were significantly higher than normal and NASH treated with curcumin rats livers. Conclusion: Our data demonstrated that curcumin prevents the NASH by mitochondria protection and apoptosis reduction and provided a possible novel treatment for NASH. 相似文献
72.
Background:
In China, tracheobronchial foreign body (TFB) aspiration, a major cause of emergency episode and accident death in children, remains a challenge for anesthetic management. Here, we share our experience and discuss the anesthetic consideration and management of patients with TFB aspiration.Methods:
This was a single-institution retrospective study in children with an inhaled foreign body between 1991 and 2010 that focused on the complications following rigid bronchoscopy (RB). Data including the clinical characteristics of patients and TFB, anesthetic method, and postoperative severe complications were analyzed by different periods.Results:
During the 20-year study period, the charts of 3149 patients who underwent RB for suspected inhaled TFB were reviewed. There were 2079 male and 1070 female patients (1.94:1). A nut (84%) was the most commonly inhaled object. The study revealed a 9% (n = 284) overall rate of severe postoperative complications related to severe hypoxemia, laryngeal edema, complete laryngospasm, pneumothorax, total segmental atelectasis, and death with incidences of 3.2%, 0.9%, 1.3%, 0.3%, 0.3%, and 0.1%, respectively. The rates of preoperative airway impairment, negative findings of TFB, and adverse postoperative events have been on the rise in the past 5 years.Conclusions:
The survey results confirmed that hypoxemia remains the most common postoperative complication in different periods. Both controlled ventilation and spontaneous ventilation were effective during the RB extraction of the foreign body at our hospital in the modern technique period. An active respiratory symptom was commonly seen in the groups with negative findings. 相似文献73.
Sub‐hubs of baseline functional brain networks are related to early improvement following two‐week pharmacological therapy for major depressive disorder 下载免费PDF全文
Lei Zhang Luoyi Xu Rui Feng Liqiang Cai Jing Liu Jinhui Wang Wei Chen 《Human brain mapping》2015,36(8):2915-2927
Accumulating evidence suggests that early improvement after two‐week antidepressant treatment is predictive of later outcomes of patients with major depressive disorder (MDD); however, whether this early improvement is associated with baseline neural architecture remains largely unknown. Utilizing resting‐state functional MRI data and graph‐based network approaches, this study calculated voxel‐wise degree centrality maps for 24 MDD patients at baseline and linked them with changes in the Hamilton Rating Scale for Depression (HAMD) scores after two weeks of medication. Six clusters exhibited significant correlations of their baseline degree centrality with treatment‐induced HAMD changes for the patients, which were mainly categorized into the posterior default‐mode network (i.e., the left precuneus, supramarginal gyrus, middle temporal gyrus, and right angular gyrus) and frontal regions. Receiver operating characteristic curve and logistic regression analyses convergently revealed excellent performance of these regions in discriminating the early improvement status for the patients, especially the angular gyrus (sensitivity and specificity of 100%). Moreover, the angular gyrus was identified as the optimal regressor as determined by stepwise regression. Interestingly, these regions possessed higher centrality than others in the brain (P < 10?3) although they were not the most highly connected hubs. Finally, we demonstrate a high reproducibility of our findings across several factors (e.g., threshold choice, anatomical distance, and temporal cutting) in our analyses. Together, these preliminary exploratory analyses demonstrate the potential of neuroimaging‐based network analysis in predicting the early therapeutic improvement of MDD patients and have important implications in guiding earlier personalized therapeutic regimens for possible treatment‐refractory depression. Hum Brain Mapp 36:2915–2927, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
74.
目的探讨股骨多段截骨髓内钉固定矫治儿童成骨不全症所致股骨畸形的疗效,分析术后并发症的防治。方法 2007年1月至2013年12月,我院共收治成骨不全所致股骨畸形患儿28例,包括39根畸形股骨。年龄3岁7个月至14岁5个月,平均8岁4个月。术中将弯曲股骨行多段截骨矫形及髓内钉固定,平均截骨1.9(1~3)处,随机分为弹性针组与Rush钉组,其中20根股骨使用弹性髓内钉,19根股骨使用Rush钉。结果随访1年3个月至5年7个月,平均3年8个月。随访后期按Sanders评分标准评定髋关节功能:弹性针组优11例,良2例,中7例,差0例;Rush钉组优16例,良2例,中1例,差0例。结论多段截骨矫形后髓内钉内固定治疗儿童成骨不全所致股骨畸形,能有效矫正股骨弯曲畸形,改善下肢外观及力线关系,防止再骨折,提高患儿生活质量,效果明确。Rush髓内钉内固定效果满意,术后再骨折概率小,股骨不易再次弯曲变形,值得临床推广。 相似文献
75.
Lee SK Lin JF Cai YQ Hiraoka N Eng PJ Okuchi T Mao HK Meng Y Hu MY Chow P Shu J Li B Fukui H Lee BH Kim HN Yoo CS 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(23):7925-7929
Silicate melts at the top of the transition zone and the core-mantle boundary have significant influences on the dynamics and properties of Earth's interior. MgSiO3-rich silicate melts were among the primary components of the magma ocean and thus played essential roles in the chemical differentiation of the early Earth. Diverse macroscopic properties of silicate melts in Earth's interior, such as density, viscosity, and crystal-melt partitioning, depend on their electronic and short-range local structures at high pressures and temperatures. Despite essential roles of silicate melts in many geophysical and geodynamic problems, little is known about their nature under the conditions of Earth's interior, including the densification mechanisms and the atomistic origins of the macroscopic properties at high pressures. Here, we have probed local electronic structures of MgSiO3 glass (as a precursor to Mg-silicate melts), using high-pressure x-ray Raman spectroscopy up to 39 GPa, in which high-pressure oxygen K-edge features suggest the formation of tricluster oxygens (oxygen coordinated with three Si frameworks; 3O) between 12 and 20 GPa. Our results indicate that the densification in MgSiO3 melt is thus likely to be accompanied with the formation of triculster, in addition to a reduction in nonbridging oxygens. The pressure-induced increase in the fraction of oxygen triclusters >20 GPa would result in enhanced density, viscosity, and crystal-melt partitioning, and reduced element diffusivity in the MgSiO3 melt toward deeper part of the Earth's lower mantle. 相似文献
76.
77.
78.
79.
Rou Jiang Xiu-Yu Cai Zhong-Han Yang Yue Yan Xiong Zou Ling Guo Rui Sun Dong-Hua Luo Qiu-Yan Chen Pei-Yu Huang Yan-Qun Xiang Xing Lu Lin Wang Wei-Xiong Xia Hai-Qiang Mai Ming-Yuan Chen 《癌症》2015,(6)
Introduction:Patients with metastatic nasopharyngeal carcinoma (NPC) have variable survival outcomes. We have previously shown that an elevated peripheral blood lymphocyte-to-monocyte ratio (LMR) is as... 相似文献
80.