全文获取类型
收费全文 | 22790篇 |
免费 | 1368篇 |
国内免费 | 139篇 |
专业分类
耳鼻咽喉 | 290篇 |
儿科学 | 434篇 |
妇产科学 | 355篇 |
基础医学 | 3627篇 |
口腔科学 | 463篇 |
临床医学 | 1902篇 |
内科学 | 4218篇 |
皮肤病学 | 915篇 |
神经病学 | 2499篇 |
特种医学 | 1542篇 |
外科学 | 3175篇 |
综合类 | 104篇 |
一般理论 | 10篇 |
预防医学 | 887篇 |
眼科学 | 371篇 |
药学 | 1987篇 |
中国医学 | 31篇 |
肿瘤学 | 1487篇 |
出版年
2023年 | 97篇 |
2022年 | 80篇 |
2021年 | 313篇 |
2020年 | 264篇 |
2019年 | 343篇 |
2018年 | 375篇 |
2017年 | 346篇 |
2016年 | 452篇 |
2015年 | 592篇 |
2014年 | 673篇 |
2013年 | 908篇 |
2012年 | 1373篇 |
2011年 | 1520篇 |
2010年 | 954篇 |
2009年 | 919篇 |
2008年 | 1494篇 |
2007年 | 1598篇 |
2006年 | 1488篇 |
2005年 | 1434篇 |
2004年 | 1416篇 |
2003年 | 1418篇 |
2002年 | 1374篇 |
2001年 | 289篇 |
2000年 | 214篇 |
1999年 | 295篇 |
1998年 | 349篇 |
1997年 | 298篇 |
1996年 | 190篇 |
1995年 | 212篇 |
1994年 | 199篇 |
1993年 | 206篇 |
1992年 | 135篇 |
1991年 | 121篇 |
1990年 | 111篇 |
1989年 | 107篇 |
1988年 | 121篇 |
1987年 | 105篇 |
1986年 | 83篇 |
1985年 | 81篇 |
1984年 | 110篇 |
1983年 | 96篇 |
1982年 | 110篇 |
1981年 | 105篇 |
1980年 | 115篇 |
1979年 | 62篇 |
1978年 | 61篇 |
1977年 | 87篇 |
1976年 | 73篇 |
1975年 | 66篇 |
1974年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
1.
2.
A major advance was made to reduce the side effects of cancer therapy via the elucidation of the tumor-specific lytic path “hyperploid progression-mediated death” targeting retinoblastoma (Rb) or p53-mutants defective in G1 DNA damage checkpoint. The genetic basis of human cancers was uncovered through the cloning of the tumor suppressor Rb gene. It encodes a nuclear DNA-binding protein whose self-interaction is regulated by cyclin-dependent kinases. A 3D-structure of Rb dimer is shown, confirming its multimeric status. Rb assumes a central role in cell cycle regulation and the “Rb pathway” is universally inactivated in human cancers. Hyperploidy refers to a state in which cells contain one or more extra chromosomes. Hyperploid progression occurs due to continued cell-cycling without cytokinesis in G1 checkpoint-defective cancer cells. The evidence for the triggering of hyperploid progression-mediated death in RB-mutant human retinoblastoma cells is shown. Hence, the very genetic mutation that predisposes to cancer can be exploited to induce lethality. The discovery helped to establish the principle of targeted cytotoxic cancer therapy at the mechanistic level. By triggering the lytic path, targeted therapy with tumor specificity at the genetic level can be developed. It sets the stage for systematically eliminating side effects for cytotoxic cancer therapy. 相似文献
3.
Paul Tetteh Asare Nadeeka Bandara Tae-Yong Jeong Sangryeol Ryu Jochen Klumpp Kwang-Pyo Kim 《Archives of virology》2015,160(10):2647-2650
4.
5.
Erika Cecon Anna Ivanova Marine Luka Florence Gbahou Anne Friederich Jean‐Luc Guillaume Patrick Keller Klaus Knoch Raise Ahmad Philippe Delagrange Michele Solimena Ralf Jockers 《Journal of pineal research》2019,66(2)
Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies. 相似文献
6.
7.
8.
The ban of lead in many electronic products and the expectation that, sooner or later, this ban will include the currently exempt piezoelectric ceramics based on Lead-Zirconate-Titanate has motivated many research groups to look for lead-free substitutes. After a short overview on different classes of lead-free piezoelectric ceramics with large strain, this review will focus on Bismuth-Sodium-Titanate and its solid solutions. These compounds exhibit extraordinarily high strain, due to a field induced phase transition, which makes them attractive for actuator applications. The structural features of these materials and the origin of the field-induced strain will be revised. Technologies for texturing, which increases the useable strain, will be introduced. Finally, the features that are relevant for the application of these materials in a multilayer design will be summarized. 相似文献
9.
Marie Warrer Petersen Tine Sylvest Meyhoff Marie Helleberg Maj-Brit Nørregaard Kjær Anders Granholm Carl Johan Steensen Hjortsø Thomas Steen Jensen Morten Hylander Møller Peter Buhl Hjortrup Mik Wetterslev Gitte Kingo Vesterlund Lene Russell Vibeke Lind Jørgensen Klaus Tjelle Thomas Benfield Charlotte Suppli Ulrik Anne Sofie Andreasen Thomas Mohr Morten H. Bestle Lone Musaeus Poulsen Mette Friberg Hitz Thomas Hildebrandt Lene Surland Knudsen Anders Møller Christoffer Grant Sølling Anne Craveiro Brøchner Bodil Steen Rasmussen Henrik Nielsen Steffen Christensen Thomas Strøm Maria Cronhjort Rebecka Rubenson Wahlin Stephan Jakob Luca Cioccari Balasubramanian Venkatesh Naomi Hammond Vivekanand Jha Sheila Nainan Myatra Christian Gluud Theis Lange Anders Perner 《Acta anaesthesiologica Scandinavica》2020,64(9):1365-1375
Introduction
Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists.Methods
The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals.Discussion
The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.10.
Schmitz Jan Jansen Stefanie Meyer Moritz Hinkelbein Jochen 《Notfall & Rettungsmedizin》2022,25(4):285-293
Notfall + Rettungsmedizin - Tauchunfälle sind vergleichsweise selten und stellen (Erst‑)Helfer vor besondere Herausforderungen. Sie müssen schnell und kompetent behandelt werden, da... 相似文献