全文获取类型
收费全文 | 10976篇 |
免费 | 1237篇 |
国内免费 | 185篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 120篇 |
妇产科学 | 23篇 |
基础医学 | 1103篇 |
口腔科学 | 61篇 |
临床医学 | 1267篇 |
内科学 | 910篇 |
皮肤病学 | 71篇 |
神经病学 | 1196篇 |
特种医学 | 538篇 |
外科学 | 402篇 |
综合类 | 1050篇 |
预防医学 | 348篇 |
眼科学 | 3993篇 |
药学 | 815篇 |
2篇 | |
中国医学 | 285篇 |
肿瘤学 | 135篇 |
出版年
2024年 | 33篇 |
2023年 | 231篇 |
2022年 | 329篇 |
2021年 | 585篇 |
2020年 | 559篇 |
2019年 | 433篇 |
2018年 | 494篇 |
2017年 | 513篇 |
2016年 | 477篇 |
2015年 | 499篇 |
2014年 | 741篇 |
2013年 | 877篇 |
2012年 | 675篇 |
2011年 | 643篇 |
2010年 | 538篇 |
2009年 | 541篇 |
2008年 | 462篇 |
2007年 | 424篇 |
2006年 | 436篇 |
2005年 | 374篇 |
2004年 | 323篇 |
2003年 | 245篇 |
2002年 | 226篇 |
2001年 | 199篇 |
2000年 | 162篇 |
1999年 | 101篇 |
1998年 | 118篇 |
1997年 | 105篇 |
1996年 | 83篇 |
1995年 | 79篇 |
1994年 | 63篇 |
1993年 | 54篇 |
1992年 | 65篇 |
1991年 | 46篇 |
1990年 | 46篇 |
1989年 | 48篇 |
1988年 | 41篇 |
1987年 | 38篇 |
1986年 | 38篇 |
1985年 | 70篇 |
1984年 | 62篇 |
1983年 | 51篇 |
1982年 | 56篇 |
1981年 | 60篇 |
1980年 | 45篇 |
1979年 | 30篇 |
1978年 | 26篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1973年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 406 毫秒
51.
Floris E. A. Udink ten Cate Ingo Germund Stijn S. Goossens Gerardus Bennink Narayanswami Sreeram 《Echocardiography (Mount Kisco, N.Y.)》2019,36(6):1211-1216
We describe a Fontan patient with severe heart failure who was successfully treated with biventricular cardiac resynchronization therapy (CRT). Our case shows that strain imaging might play a crucial role in guiding placement of pacing leads and in characterizing the electromechanical substrate associated with a favorable CRT response. Furthermore, we demonstrate for the first time that ventriculo‐ventricular interdependency seems an important mechanical concept, which can be utilized to augment cardiac performance in failing Fontan patients with a functional hypoplastic ventricle. 相似文献
52.
53.
54.
Sharon D'Souza Edwin James Rishi Swarup Sheetal Mahuvakar Aditya Pradhan Krati Gupta 《Indian journal of ophthalmology》2020,68(12):2888
Dry eye disease (DED) is a condition that is fast reaching epidemic proportions around the world. Dry eye post-refractive surgery is the leading cause of iatrogenically induced DED. The wide variety of presentations and the disparity between signs and symptoms in many patients make this a very challenging aspect of our clinical practice. There has been a paradigm shift in the way we approach and treat this condition. The International Dry eye workshop has added new knowledge and focus to our management of dry eye. A wide range of newer diagnostic modalities are available for the diagnosis of DED. Dry eye is one of the most common side effects of refractive surgery and can have a bearing the patient''s perception of surgical outcomes as well. A thorough understanding of the possible underlying etiopathologies of this disease and the difference in etiopathogenesis of postrefractive dry eye is essential for optimal outcomes. It is important to approach each case in a unique fashion and customize the therapy to the patient presentation. This review article compiles all these aspects of management of dry eye in general, and postrefractive surgery dry eye in particular; from the ones commonly practiced in the clinic to the newer modalities of therapy with insights into the disease from a more practical point of view. 相似文献
55.
56.
Esin Benli Küçük Ercan Kaydok Kürsad Ramazan Zor Gamze Yıldırım Biçer 《Topics in stroke rehabilitation》2020,27(8):630-635
ABSTRACT Objective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group. Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared. Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group. Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients. 相似文献
57.
58.
目的通过应用Keratograph 5M眼表综合分析仪对飞秒激光小切口角膜基质透镜取出手术(SMILE)术中第二术眼不同保护措施的首次泪膜破裂时间(NIKBUTf)和平均泪膜破裂时间(NIKBUTav)变化情况进行对比研究,观察不同保护措施对泪膜稳定性的影响。方法选取2019年6月至2019年11月在重庆眼视光眼科医院行SMILE手术的患者作为研究对象。患者左眼为观察眼,SMILE术中在右眼行手术时,左眼按照不同处理方法分为3组,分别给予小牛血去蛋白眼用凝胶点眼、使用眼罩,以及空白对照。并分别在右眼手术前后,使用Keratograph 5M眼表综合分析仪,完成左眼NIKBUTf和NIKBUTav检测,进行对比研究。采用SPSS 25.0进行统计学分析。结果共35例患者(35左眼)纳入研究,其中小牛血去蛋白眼用凝胶组12例,眼罩组11例,空白对照组12例。重复测量方差分析NIKBUTf和NIKBUTav均存在时间效应和分组效应,且时间与分组存在交互作用(P<0.05)。凝胶组左眼NIKBUTf在右眼手术前和右眼手术后即刻无统计学差异(P>0.05),凝胶组左眼NIKBUTav在右眼SMILE手术后即刻较右眼手术前延长(P<0.05)。眼罩组和对照组(空白)左眼NIKBUTf和NIKBUTav在右眼手术后即刻均缩短(P<0.05)。对照组NIKBUTf和NIKBUTav缩短最明显(P<0.05)。结论不同保护措施和时间变化均对NIKBUTf和NIKBUTav产生了影响,小牛血去蛋白提取物眼用凝胶应用于SMILE术中第二术眼的保护措施起到了保护泪膜稳定性的作用。眼罩对第二术眼的泪膜保护作用并不明显,常规手术操作对第二术眼无保护措施的情况下泪膜稳定性最差。 相似文献
59.
Yinlei
Wen Huaguang Zhang Hanguang Su He Ren 《Optimal control applications & methods.》2020,41(4):1233-1250
In this article, a model-free off-policy reinforcement learning algorithm is applied to address the optimal tracking problem based on multiplayer non-zero-sum games for discrete-time linear systems. In contrast to the traditional method and the policy iteration method for solving the optimal tracking problems, the proposed algorithm operates with the system data rather than the knowledge of the system dynamics. For performing the proposed algorithm, an auxiliary augmented system is constructed via assembling the original system and the reference trajectory while a discount factor is introduced into the performance indexes. It is analyzed that the solutions of the proposed algorithm converge to the Nash equilibrium and the result is not influenced by the probing noise. Two simulations are presented to verify the feasibility and effectiveness of the proposed algorithm. 相似文献
60.
《The ocular surface》2020,18(1):108-113
PurposeAromatase inhibitors (AIs) limit the synthesis of oestrogen in peripheral tissues thus lowering levels of oestrogen. The primary aim was to evaluate whether women treated with AIs have altered dry eye symptoms and signs. A sub-aim was to investigate whether symptoms of dry eye in postmenopausal women were associated with symptoms of non-eye pain, ocular pain and self-rated pain perception.MethodsThis cross-sectional, observational, single visit study recruited 56 postmenopausal women (mean age 64.1 + 7.9 years) and 52 undergoing AI treatment (mean age 66.6 + 9.0). Ocular symptoms (OSDI, MGD14) and pain questionnaires (PSQ, OPAS) were administered and signs of dry eye and meibomian gland dysfunction were evaluated.ResultsAlmost half of each group reported dry eye symptoms, defined as OSDI>12 (48% control, 46% AI). The PSQ score was significantly higher in the AI group (p = 0.04). Neither frequency or severity of dry eye (or MGD) symptoms scores were significantly different between groups. In the AI group, meibomian gland expressibility score was worse (p = 0.003); there were no differences in any other signs. Higher OSDI scores were associated with higher OPAS eye-pain scores (r = 0.49, p < 0.001), but not OPAS non-eye pain (r = 0.09, p = 0.35). Pain perception (PSQ) showed a moderate positive association with OPAS eye-pain (r = 0.30, p = 0.003).ConclusionsIn this study elevated ocular symptoms were observed in both the AI treated and the untreated groups, with no difference between the groups. Women undergoing AI treatment for early stage breast cancer had worse meibum expressibility score and increased pain perception compared to an untreated group of women. 相似文献