全文获取类型
收费全文 | 7960篇 |
免费 | 405篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 176篇 |
儿科学 | 198篇 |
妇产科学 | 177篇 |
基础医学 | 1589篇 |
口腔科学 | 194篇 |
临床医学 | 599篇 |
内科学 | 1449篇 |
皮肤病学 | 159篇 |
神经病学 | 727篇 |
特种医学 | 239篇 |
外科学 | 903篇 |
综合类 | 34篇 |
预防医学 | 596篇 |
眼科学 | 182篇 |
药学 | 851篇 |
中国医学 | 32篇 |
肿瘤学 | 288篇 |
出版年
2023年 | 75篇 |
2022年 | 223篇 |
2021年 | 294篇 |
2020年 | 152篇 |
2019年 | 208篇 |
2018年 | 309篇 |
2017年 | 238篇 |
2016年 | 293篇 |
2015年 | 293篇 |
2014年 | 343篇 |
2013年 | 602篇 |
2012年 | 761篇 |
2011年 | 778篇 |
2010年 | 468篇 |
2009年 | 265篇 |
2008年 | 197篇 |
2007年 | 215篇 |
2006年 | 189篇 |
2005年 | 145篇 |
2004年 | 126篇 |
2003年 | 114篇 |
2002年 | 76篇 |
2001年 | 109篇 |
2000年 | 99篇 |
1999年 | 116篇 |
1998年 | 65篇 |
1997年 | 57篇 |
1996年 | 54篇 |
1995年 | 64篇 |
1994年 | 56篇 |
1993年 | 39篇 |
1992年 | 42篇 |
1991年 | 45篇 |
1990年 | 50篇 |
1989年 | 44篇 |
1988年 | 55篇 |
1987年 | 57篇 |
1986年 | 44篇 |
1985年 | 64篇 |
1984年 | 52篇 |
1983年 | 62篇 |
1982年 | 60篇 |
1981年 | 51篇 |
1980年 | 41篇 |
1979年 | 46篇 |
1978年 | 47篇 |
1977年 | 36篇 |
1976年 | 48篇 |
1975年 | 45篇 |
1974年 | 33篇 |
排序方式: 共有8393条查询结果,搜索用时 15 毫秒
151.
Góreczny S Dryżek P Moszura T Politowska B Niedzielska-Stanek B Moll JA Sysa A 《Kardiologia polska》2012,70(5):505-507
In presented case rotational angiography with three dimensional reconstruction (3DRA) was used for diagnostic and control angiograms during covered CP stent implantation in patient with critical aortic coarctation and patent ductus arteriosus. Administering less contrast then for standard two perpendicular projections, good quality images were obtained in at least seven projections. 相似文献
152.
153.
Koštál V Šimek P Zahradníčková H Cimlová J Štětina T 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(9):3270-3274
Among vertebrates, only a few species of amphibians and reptiles tolerate the formation of ice crystals in their body fluids. Freeze tolerance is much more widespread in invertebrates, especially in overwintering insects. Evolutionary adaptations for freeze tolerance are considered to be highly complex. Here we show that surprisingly simple laboratory manipulations can change the chill susceptible insect to the freeze tolerant one. Larvae of Drosophila melanogaster, a fruit fly of tropical origin with a weak innate capacity to tolerate mild chilling, can survive when approximately 50% of their body water freezes. To achieve this goal, synergy of two fundamental prerequisites is required: (i) shutdown of larval development by exposing larvae to low temperatures (dormancy) and (ii) incorporating the free amino acid proline in tissues by feeding larvae a proline-augmented diet (cryopreservation). 相似文献
154.
Recent findings show that food craving represents an important co-factor in overweight and obesity etiology and its severity represents a good predictor of relapse during active weight control. Child overweight and obesity also represents significant predictive factor of adulthood obesity and evidence about its incidence in children is therefore important. In order to achieve this evidence the indices of food craving has measured in 150 older school age children (54 boys and 96 girls; mean age 13.6 ± 1.2). The food craving symptoms were measured by validated Czech translation of the General Food-Craving Questionnaire-Trait (G-FCQ-T). Body proportions of children were indexed by body-mass index (BMI). BMI were assessed according to cut-off points BMI references from the Czech Republic. Results have shown that older school children have experience with food craving symptoms, and that intensity of these symptoms is significantly associated with BMI value (r = 0.55; p < 0.0001). Statistical analysis also revealed higher incidence of food craving symptoms intensity in girls. These findings provide basic normative data about food craving symptoms occurrence and intensity in older school age children group. Presented results also indirectly support the hypothesis that food craving could represent important co-factor in childhood obesity etiology. The consequences for obesity psychotherapy will be discussed. 相似文献
155.
156.
The elderly with diabetes mellitus are usually treated with many types of drugs. This, together with pharmacokinetic and pharmacodynamic changes connected with aging, can lead to an occurrence of drug interactions. They are often manifested as hypoglycaemia, decompensation of diabetes or an increase of frequency of adverse effects of drugs used together. It is important to pay an attention especially to hypoglycaemia, which brings many risks in the elderly. An article is focused on probable drug interactions when combination of various antidiabetics, antidiabetics with antihypertensives or hypolipidemics is used. Despite ACE-inhibitors and beta-blockers can influence the compensation of diabetics, their use is not contraindicated in these patients, because of their huge benefit in the prevention of cardiovascular events. An article brings an overview of antidiabetics metabolised by means of the system of cytochrome P 450 and resulting drug interactions with inhibitors and inductors of these enzymes. These drug interactions are not usually important in clinical practice and it is possible to prevent them with careful monitoring of glycaemia, instruction of patients and alternatively modification of the doses of hypoglycaemic medication after a termination of the treatment of responsible inductor or inhibitor. 相似文献
157.
158.
Glucocorticosteroids are still very important part of the treatment of chronic inflammatory disorders. Their use is often accompanied by unpleasant adverse effects, problems associated with withdrawal during their long-term use and interactions with concomitantly administered drugs. One of the important interactions that may often occur in clinical practice is interaction with warfarin. Despite the fact that as glucocorticosteroids so warfarin are used for many years and seem to be completely known, their co-administration is still accompanied by uncertainties. The interaction may have pharmacodynamic or pharmacokinetic character and both types result in increased risk of bleeding. The pharmacodynamic interaction can be expected to increase a risk of gastrointestinal bleeding to which a gastrotoxicity of glucocorticosteroids contributes. A pharmacokinetic interaction is considered to influence a hepatic metabolism of warfarin and to increase its availability. The exact mechanism is still not fully understood. Manifestations of both types of interactions are taken up with a delay. Co-administration requires increased attention and close monitoring of international normalized ratio. At higher doses of glucocorticosteroids proton pump inhibitors are also effective in prevention of gastrotoxicity. 相似文献
159.
160.
Proteomic analysis of the human body is a significant recent scientific endeavour. In this study, we investigated the proteomic profile of human dentin using modern analytical and mass spectrometric techniques. Five healthy permanent human molars from five adults were cut, pulverized, denaturated with guanidine buffer, and demineralized with EDTA buffer. The extracted proteins were analysed by gel electrophoresis (SDS-PAGE and two-dimensional gel electrophoresis), digested with trypsin, and separated by liquid chromatography/high-resolution tandem mass spectrometry. We identified 289 proteins with high confidence, 90 of which had not been previously detected in human dentin. Nine (currently hypothetical) proteins were identified for the first time in an actual human sample. The proteins have a variety of functions, including calcium-ion binding, formation of the extracellular matrix, formation of the cytoskeleton, cytoskeletal protein binding, immune response, and transport. In conclusion, this is the first use of two-dimensional electrophoresis for investigating human dentin. 相似文献