全文获取类型
收费全文 | 22447篇 |
免费 | 1852篇 |
国内免费 | 623篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 320篇 |
妇产科学 | 193篇 |
基础医学 | 1610篇 |
口腔科学 | 167篇 |
临床医学 | 1930篇 |
内科学 | 5172篇 |
皮肤病学 | 313篇 |
神经病学 | 1149篇 |
特种医学 | 583篇 |
外国民族医学 | 1篇 |
外科学 | 2478篇 |
综合类 | 1668篇 |
现状与发展 | 2篇 |
预防医学 | 659篇 |
眼科学 | 242篇 |
药学 | 5405篇 |
10篇 | |
中国医学 | 317篇 |
肿瘤学 | 2598篇 |
出版年
2024年 | 30篇 |
2023年 | 518篇 |
2022年 | 626篇 |
2021年 | 1099篇 |
2020年 | 1041篇 |
2019年 | 941篇 |
2018年 | 841篇 |
2017年 | 940篇 |
2016年 | 857篇 |
2015年 | 959篇 |
2014年 | 1291篇 |
2013年 | 2519篇 |
2012年 | 1170篇 |
2011年 | 1337篇 |
2010年 | 1018篇 |
2009年 | 1026篇 |
2008年 | 998篇 |
2007年 | 949篇 |
2006年 | 877篇 |
2005年 | 713篇 |
2004年 | 572篇 |
2003年 | 563篇 |
2002年 | 508篇 |
2001年 | 394篇 |
2000年 | 330篇 |
1999年 | 278篇 |
1998年 | 272篇 |
1997年 | 260篇 |
1996年 | 209篇 |
1995年 | 198篇 |
1994年 | 162篇 |
1993年 | 159篇 |
1992年 | 120篇 |
1991年 | 108篇 |
1990年 | 100篇 |
1989年 | 92篇 |
1988年 | 77篇 |
1987年 | 94篇 |
1986年 | 64篇 |
1985年 | 85篇 |
1984年 | 81篇 |
1983年 | 57篇 |
1982年 | 80篇 |
1981年 | 57篇 |
1980年 | 57篇 |
1979年 | 45篇 |
1978年 | 44篇 |
1977年 | 28篇 |
1976年 | 28篇 |
1973年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Cheryce M. Poon M.D. Robert A. Koenigsberg D.O. Betsy A. Izes M.D. 《Emergency radiology》1997,4(5):264-267
Angioedema of the oropharynx and hypopharynx due to oral angiotensin-converting enzyme (ACE) inhibitors is a potentially life-threatening event and has not been well described in the radiology literature. A retrospective review of the clinical and radiologic findings in three patients with angioedema due to ACE inhibitor use was performed.Our subgroup of patients treated with ACE inhibitors presented with varying degrees of dysphagia, dyspnea, and facial swelling. Plain radiographic findings included enlargement of the epiglottis, aryepiglottic folds, and prevertebral and submental soft tissue. Computed tomography confirmed extensive retropharyngeal and subcutaneous edema. Clinical symptoms resolved in each case in 24–48 hours with cessation of the ACE inhibitor and concomitant steriod therapy.Our cases demonstrate the typical clinical and radiographic presentation of neck angioedema in the setting of ACE inhibitor use. As ACE inhibitors are increasingly being used as first-line agents in the treatment of hypertension, we caution that neck angioedema may be encountered with increased frequency in adults. Early recognition and immediate intervention result in rapid resolution of this potentially life-threatening event. 相似文献
102.
GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
103.
制备了聚乙烯醇 (PVA)与聚苯乙烯磺酸 (PSSA)的共混膜 ,并研究了膜的组成、热处理温度、甲醇水溶液浓度等对膜电导率和甲醇透过率的影响。与目前普遍使用的NafionTM膜相比 ,这种由阻醇材料PVA与离子交换材料PSSA共混后形成的聚合物膜既能提高阻醇性能 ,又具有一定的电导率。一种以聚苯乙烯磺酸含量为 17%的膜 ,其电导率可达 3× 10 -3 S·cm-1,但甲醇透过率P仅为 2× 10 -8cm2 ·s-1。如果以σ/P为综合指标 ,则此膜的综合性能比NafionTM膜高约 4 0倍 相似文献
104.
105.
Brian J. Soher Peter C. M. van Zijl Jeffrey H. Duyn Peter B. Barker 《Magnetic resonance in medicine》1996,35(3):356-363
Multislice proton MR spectroscopic images (SI) of the brain were quantitated, using the phantom replacement technique. In 16 normal volunteers, ranging in age from 5 to 74 years, average “whole brain” concentrations of choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) were found to be 2.4 ± 0.4, 7.9 ± 1.3, and 11.8 ± 1.0 (mM, mean ± SD), respectively. These values are in good general agreement with those previously determined by single-voxel localization techniques. Cortical gray matter was found to have lower Cho and NAA levels, compared to those of white matter, corpus callosum, and basal ganglia. Cho was also found to increase significantly with age in several locations. Quantitative multislice proton SI is feasible in the clinical environment, and regional and age-dependent variations occur that must be accounted for when evaluating spectra from pathological conditions. 相似文献
106.
Activated prothrombin complex concentrate (FEIBA® ) treatment during surgery in patients with inhibitors to FVIII/IX 总被引:1,自引:0,他引:1
Non-activated and activated prothrombin complex concentrates (PCC/aPCC) have been used successfully to treat bleeds in haemophilia patients with inhibitors, but most physicians do not consider these products as effective as factor VIII/IX (FVIII/IX) concentrates in non-inhibitor patients. Thus, surgical procedures in inhibitor patients have been performed reluctantly. We have performed 14 minor and five major surgical and invasive diagnostic procedures in eight patients with congenital haemophilia A and inhibitors and in two patients with acquired haemophilia. When a loading dose of 100 U kg-1 of FEIBA was given followed by 200 U kg-1 day-1 in three divided doses every 8 h for 3 days, and then, when the daily dose was tapered to 100-150 U kg-1, no severe or unexpected bleeding complications were observed. However, one adverse event was observed. A 69-year-old man who suffered a myocardial infarction the third postoperative day following sigmoidectomy was managed safely with opiate analgesia, nitrates and diuretics, and the continued use of FEIBA(R). 相似文献
107.
肝纤维化组织中MMP1、TIMP1的表达及其临床意义 总被引:2,自引:1,他引:1
目的 :检测肝纤维化组织中基质金属蛋白酶 1 (MMP1 )、基质金属蛋白酶组织抑制因子 1 (TIMP1 )的表达 ,为肝纤维化的诊治提供重要的分子生物学指标。 方法 :采用链霉菌抗生物蛋白 -过氧化酶联接法 (S- P法 )检测70例肝纤维化组织中 MMP1 、TIMP1 的表达。结果:(1) TIMP1 蛋白阳性表达随肝纤维化程度的加重而增强 ,并且呈正相关关系 (r=0 .92 74 ,P <0 .0 1)。 (2 ) MMP1 蛋白阳性表达随肝纤维化程度的加重无明显变化 ,无相关关系(r =0 .2 181,P >0 .0 5 )。 结论:TIMP1 与肝纤维化的发生、发展密切相关 ,随纤维化发生、发展阳性表达增强。从分子水平对肝纤维化、肝硬化病变进行评估 ,为早期诊治肝纤维化和判断预后提供依据。 相似文献
108.
109.
Giovanni Vanni Frajese Flavio Pozzi Gaetano Frajese 《Clinical Interventions in Aging》2006,1(4):439-449
Prevalence and severity of erectile dysfunction (ED) increase with aging and are often associated with illnesses, like diabetes mellitus, heart disease, and hypertension, pathologically characterized by endothelial dysfunction and whose prevalence increases with age. The assumption that ED is mainly a neurovascular disease is supported by the evidence that specific phosphodiesterase type 5 (PDE5) inhibition produces an efficient erection in a wide range of ages and conditions. The availability of specific PDE5 inhibitors has enabled the development of effective treatment strategies, in this contest, tadalafil may be considered as the least “typical” PDE5 inhibitor. In clinical trials, tadalafil significantly enhanced, in patients of different ages, all efficacy outcomes across disease etiologies and severities. With an effectiveness lasting up to 36h, tadalafil allows patients to choose when to have sexual activities without the need to time it, showing positive feedback in terms of quality of life related to the treatment. Headache and dyspepsia were the most frequent side-effects of tadalafil, followed by back pain, nasal congestion, myalgia, and flushing, but the impact that long time action could have on effectiveness and safety is not yet entirely defined. The aim of this article is to critically review the available evidence from the tadalafil clinical research program and give the physician a rational approach for intervention in the treatment of ED and related diseases. 相似文献
110.
中央腺体内前列腺癌3D 1 H-MRSI的初步研究 总被引:12,自引:0,他引:12
目的 应用3D氢质子磁共振波谱成像(3D ^1H-MRSI)研究中央腺体(CG)前列腺癌(PC)的代谢特点,并初步探讨3D ^1H-MRSI对CG内PC的鉴别诊断价值。资料与方法 分析18例良性前列腺增生(BPH)和16例PC的3D ^1H-MRSI表现,16例PC中2例源于CG,14例肿块较大同时累及外周带和CG。测量CG内PC及BPH的CG体素(Cho+Cre)/Cit比值及Cho/Cre比值,并分别对PC与BPH体素的两组代谢物比值进行比较。结果 CG内PC波谱主要表现为Cit峰明显下降甚至消失,Cho峰显著升高,两者波峰可呈现倒置。CG的腺体增生组织主要表现为Cit峰高耸,Cho峰次之,Cre峰最低,基质增生者Cit、Cho峰均降低;CG内PC体素(Cho+Cre)/Cit比值显著高于BPH的CG(P〈0.001),但两组体素存在部分重叠(29/133,21.8%)。CG内PC体素的Cho/Cre比值明显高于BPH的CG(P〈0.001),但两组之间重叠较多(105/133,78.9%)。结论 CG内PC的诊断存在一定困难,其(Cho+Cre)/Cit明显高于BPH的CG,但与BPH有部分重叠,综合Cit峰降低、Cho峰升高、Cho/Cre增大有助于CG内PC的检出。 相似文献