全文获取类型
收费全文 | 8540篇 |
免费 | 520篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 126篇 |
儿科学 | 264篇 |
妇产科学 | 263篇 |
基础医学 | 878篇 |
口腔科学 | 145篇 |
临床医学 | 780篇 |
内科学 | 2230篇 |
皮肤病学 | 80篇 |
神经病学 | 836篇 |
特种医学 | 327篇 |
外科学 | 940篇 |
综合类 | 93篇 |
一般理论 | 6篇 |
预防医学 | 986篇 |
眼科学 | 158篇 |
药学 | 557篇 |
中国医学 | 2篇 |
肿瘤学 | 415篇 |
出版年
2024年 | 7篇 |
2023年 | 35篇 |
2022年 | 58篇 |
2021年 | 174篇 |
2020年 | 83篇 |
2019年 | 167篇 |
2018年 | 190篇 |
2017年 | 159篇 |
2016年 | 145篇 |
2015年 | 170篇 |
2014年 | 279篇 |
2013年 | 389篇 |
2012年 | 629篇 |
2011年 | 688篇 |
2010年 | 377篇 |
2009年 | 372篇 |
2008年 | 567篇 |
2007年 | 686篇 |
2006年 | 639篇 |
2005年 | 613篇 |
2004年 | 576篇 |
2003年 | 526篇 |
2002年 | 464篇 |
2001年 | 97篇 |
2000年 | 64篇 |
1999年 | 78篇 |
1998年 | 103篇 |
1997年 | 76篇 |
1996年 | 59篇 |
1995年 | 68篇 |
1994年 | 47篇 |
1993年 | 46篇 |
1992年 | 47篇 |
1991年 | 29篇 |
1990年 | 36篇 |
1989年 | 60篇 |
1988年 | 35篇 |
1987年 | 24篇 |
1986年 | 23篇 |
1985年 | 20篇 |
1984年 | 30篇 |
1983年 | 20篇 |
1982年 | 23篇 |
1981年 | 18篇 |
1980年 | 16篇 |
1979年 | 7篇 |
1978年 | 14篇 |
1977年 | 11篇 |
1976年 | 9篇 |
1971年 | 6篇 |
排序方式: 共有9086条查询结果,搜索用时 0 毫秒
101.
102.
103.
104.
105.
A note of encouragement to those hesitant or waiting to write for our journal, together with a guide to some of the ‘props’ of the trade. 相似文献
106.
Davina Perera Michael Medini Deepika Seethamraju Ron Falkowski Kristopher White 《Journal of microencapsulation》2013,30(5):475-481
AbstractCell microencapsulation can be used in tissue engineering as a scaffold or physical barrier that provides immunoisolation for donor cells. When used as a barrier, microencapsulation shields donor cells from the host immune system when implanted for cell therapies. Maximizing therapeutic product delivery per volume of microencapsulated cells necessitates first optimising the viability of entrapped cells. Although cell microencapsulation within alginate is well described, best practices for cell microencapsulation within polyethylene glycol is still being elucidated. In this study we microencapsulate mouse preosteoblast cells within polyethylene glycol diacrylate (PEGDA) hydrogel microspheres of varying molecular weight or seeding densities to assess cell viability in relation to cell density and polymer molecular weight. Diffusion studies revealed molecule size permissible by each molecular weight PEGDA towards correlating viability with polymer mesh size. Results demonstrated higher cell viability in higher molecular weight PEGDA microspheres and when cells were seeded at higher cell densities. 相似文献
107.
Annie Delaunois Pierrette De Ron Eric Detrait Michel Guyaux 《Fundamental & clinical pharmacology》2013,27(4):354-363
We used conscious tethered Sprague‐Dawley rats to evaluate the cardiovascular effects of four sigma‐1 (σ1) agonists and five antagonists, given alone or in combination. All drugs were administered as a single intraperitoneal dose. The agonists were given at doses reported as efficacious in rodent cognition models, while the antagonists were administered at doses neutralizing agonist effects in vivo. Systolic blood pressure (SBP) and heart rate (HR) were continuously recorded for 20 min before and 60 min postadministration. Immediately after injection, a sudden, transitory increase in HR and SBP was noted in all animals, because of the stress induced by handling. For both parameters, a peak value (ΔHRmax and ΔSBPmax) and an area under the curve of changes from baseline over the period 5–20 min postinjection (ΔHR_AUC5–20 min and ΔSBP_AUC5–20 min) were calculated. Three of the four σ1 agonists (SKF‐10,047, dehydroepiandrosterone (DHEAS), Compound 14) significantly reduced ΔHR_AUC5–20 min value without changing ΔHRmax, while the fourth one, SA‐4503, had no significant effect. None of the antagonists (haloperidol, rimcazole, NE‐100, and BD1047) reduced, and even one (progesterone) enhanced the stress‐induced effects on HR. No changes in SBP were noted with any compound. When the antagonist NE‐100 was administered just before SKF‐10,047, it completely reversed the inhibitory effects of the σ1 agonist on HR increase. In conclusion, we demonstrated for the first time the involvement of σ1 receptors in the regulation of handling‐induced tachycardia in the conscious rat. Although additional investigations are needed to fully understand this role, it might offer new therapeutic perspectives to σ1 ligands in the cardiovascular sphere. 相似文献
108.
Acetyl phosphate is a central metabolite involved in a broad range of versatile cellular functions. Recently it was observed that in Escherichia coli the acetyl phosphate pathway is required for efficient ATP-dependent proteolysis. Deletion of the operon coding for acetyl phosphate metabolism (ΔackApta) results in a very low cytoplasmic level of acetyl phosphate and impaired proteolysis. Here we show that the ΔackApta mutation affects additional components of the protein quality control system. Thus, this deletion is accompanied by a decrease in protein refolding and rescue from aggregates. These results indicate the involvement of the acetyl phosphate pathway in chaperone capabilities, in addition to their effect on proteolysis. 相似文献
109.
It is widely accepted that the heat shock response is critical for quality control of mature proteins. This function is carried out mainly by chaperones and proteases. Recently, a new group of conserved heat shock proteins essential for growth at high temperature has been characterized. These proteins are involved in regulating and maintaining efficient translation under heat shock. 相似文献
110.
Schoofs MW van der Klift M Hofman A de Laet CE Herings RM Stijnen T Pols HA Stricker BH 《Annals of internal medicine》2003,139(6):476-482
Since most hip fractures are related to osteoporosis, treating accelerated bone loss can be an important strategy to prevent hip fractures. Thiazides have been associated with reduced age-related bone loss by decreasing urinary calcium excretion. 相似文献