全文获取类型
收费全文 | 13530篇 |
免费 | 1288篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 115篇 |
儿科学 | 526篇 |
妇产科学 | 369篇 |
基础医学 | 1854篇 |
口腔科学 | 409篇 |
临床医学 | 1854篇 |
内科学 | 2678篇 |
皮肤病学 | 158篇 |
神经病学 | 967篇 |
特种医学 | 328篇 |
外科学 | 1635篇 |
综合类 | 345篇 |
一般理论 | 11篇 |
预防医学 | 1724篇 |
眼科学 | 194篇 |
药学 | 832篇 |
中国医学 | 11篇 |
肿瘤学 | 843篇 |
出版年
2022年 | 75篇 |
2021年 | 158篇 |
2020年 | 138篇 |
2019年 | 186篇 |
2018年 | 218篇 |
2017年 | 202篇 |
2016年 | 175篇 |
2015年 | 235篇 |
2014年 | 326篇 |
2013年 | 518篇 |
2012年 | 728篇 |
2011年 | 769篇 |
2010年 | 451篇 |
2009年 | 402篇 |
2008年 | 757篇 |
2007年 | 789篇 |
2006年 | 784篇 |
2005年 | 780篇 |
2004年 | 707篇 |
2003年 | 747篇 |
2002年 | 783篇 |
2001年 | 303篇 |
2000年 | 305篇 |
1999年 | 319篇 |
1998年 | 188篇 |
1997年 | 146篇 |
1996年 | 128篇 |
1995年 | 126篇 |
1994年 | 128篇 |
1993年 | 115篇 |
1992年 | 154篇 |
1991年 | 196篇 |
1990年 | 185篇 |
1989年 | 186篇 |
1988年 | 167篇 |
1987年 | 156篇 |
1986年 | 148篇 |
1985年 | 156篇 |
1984年 | 128篇 |
1983年 | 124篇 |
1982年 | 88篇 |
1981年 | 88篇 |
1980年 | 82篇 |
1979年 | 121篇 |
1978年 | 95篇 |
1977年 | 82篇 |
1976年 | 73篇 |
1974年 | 66篇 |
1973年 | 73篇 |
1972年 | 72篇 |
排序方式: 共有10000条查询结果,搜索用时 39 毫秒
61.
62.
63.
64.
The intra-operative histological assessment of fresh tissue can provide valuable diagnostic information and guide surgical
management, however, even a limited exposure to standard fixation agents can potentially compromise analysis. Defined handling
strategies should exist to facilitate the receipt of all specimens, in their optimal state, by the laboratory. 相似文献
65.
1. Repeated aerosolization of leukotriene C4 (LTC4) to guinea-pigs produced leftward shift in their pulmonary resistance (RL) dose-response curves to inhaled acetylcholine (ACh) without increasing the maximum responses. 2. Repeated LTC4 aerosolization did not increase airway eosinophils. 3. The 5-lipoxygenase-activating protein (FLAP) inhibitor, MK-886, prevented the leftward shift in RL dose-response curves to ACh following repeated antigen challenge in guinea-pigs. 4. MK-886 did not inhibit the increased maximal RL produced by repeated antigen challenge, nor inhibit the airway eosinophilia induced by repeated antigen challenge. 5. Our findings suggest that leukotrienes may account for the leftward shift in pulmonary resistance responses caused by antigen but do not cause the airway eosinophilia nor enhanced maximum broncho-constrictor response to antigen. 相似文献
66.
Piper I. R.; Garrioch M. A.; Souter M. J.; Andrews PJD.; Thomson D. 《British journal of anaesthesia》1998,80(5):639-643
Diaspirin cross-linked haemoglobin (DCLHb) is a new oxygen carrying blood
substitute with vasoactive properties. Vasoactive properties may be
mediated via high affinity binding of nitric oxide by the haem moiety.
Using a rodent model of head injury combined with ischaemia, we studied the
effects of DCLHb on cerebral blood flow (CBF) and intracranial pressure
(ICP). Twenty anaesthetized rats were allocated randomly to receive
treatment with DCLHb 400 mg kg-1 i.v. or placebo (oncotically matched
plasma protein substitute 4.5% i.v.). To produce diffusely increased ICP,
after a severe weight drop injury, all animals underwent a 30-min period of
bilateral carotid ligation combined with a period of induced hypotension.
After reperfusion, DCLHb or placebo was infused and the animals
instrumented for measurement of intraventricular ICP and CBF in the region
of the sensorimotor cortex using the hydrogen clearance technique. Mean
arterial pressure (MAP), ICP, cerebral perfusion pressure (CPP) (CPP = MAP
- ICP) and CBF were measured 4 h after injury in all animals. DCLHb
significantly reduced ICP from mean 13 (SEM 2) to 3 (1) mm Hg (P <
0.001), increased CPP from 52 (8) to 95 (6) mm Hg (P < 0.001) and
increased CBF from 21 (2) to 29 (2) ml 100 g-1 min-1 (P = 0.032). We
conclude that DCLHb improved CPP without a reduction in CBF in a rodent
model of post-traumatic brain swelling.
相似文献
67.
R. Wilson J. H. McKillop M. MacLean J. J. Walker W. D. Fraser† C. Gray† F. Dryburgh† J. A. Thomson 《Clinical endocrinology》1992,37(4):331-334
OBJECTIVES: There is considerable controversy in the literature as to the cause of hyperemesis gravidarum. The aim of this project was to measure a range of thyroid hormone levels in a group of hyperemetic pregnant women. PATIENTS: The study was carried out in 10 first trimester pregnant women with hyperemesis gravidarum. All had been admitted to hospital due to the severity of their symptoms. Fifty age matched, healthy first trimester pregnant women were used as controls. MEASUREMENTS: Blood samples from the women were analysed for total T3 (TT3), total T4 (TT4), free T4 (FT4), TSH, thyrotrophin receptor antibodies (TRAb), thyroid stimulating antibodies (TSAb) and thyroid microsomal and thyroglobulin antibodies. Human chorionic gonadotrophin (hCG) levels were also measured. RESULTS: While individual patients were found to have some abnormal thyroid function tests the group as a whole showed no consistent pattern of abnormality and did not differ significantly from a group of healthy first trimester pregnant women. hCG levels were also within the normal range in the hyperemetic patients. DISCUSSION: None of the women in this study received any antithyroid medication and their symptoms improved as the pregnancy progressed. These results would suggest that there is no underlying thyroid abnormality in patients with hyperemesis gravidarum. It would appear that neither thyroid hormones, nor hCG contribute to the pathogenesis of the condition. 相似文献
68.
Gail D'Onofrio Edward Bernstein Judith Bernstein Robert H. Woolard Phillip A. Brewer Sandra A. Craig Brian J. Zink 《Academic emergency medicine》1998,5(12):1200-1209
Abstract. Medical and social problems related to alcohol use are frequently seen in the ED. Often, the tempo of emergency medicine practice seems to preclude assessment beyond that required by the acute complaint. However, detection of ED patients with alcohol problems can occur using brief screening tools. This article was developed by members of the SAEM Substance Abuse Task Force, and describes screening tools that have been used successfully to identify atrisk and dependent drinkers. Their brevity, reproducibility, and accuracy vary somewhat, but screening can be realistically performed in the busy ED setting. The early detection of patients with alcohol problems would provide the opportunity for early intervention, and may reduce subsequent morbidity and mortality in this patient population. 相似文献
69.
70.
Howard L Kaufman Seunghee Kim-Schulze Kelledy Manson Gail DeRaffele Josephine Mitcham Kang Seok Seo Dae Won Kim John Marshall 《Journal of translational medicine》2007,5(1):60