全文获取类型
收费全文 | 56114篇 |
免费 | 4025篇 |
国内免费 | 665篇 |
专业分类
耳鼻咽喉 | 1000篇 |
儿科学 | 900篇 |
妇产科学 | 1211篇 |
基础医学 | 8029篇 |
口腔科学 | 1140篇 |
临床医学 | 4753篇 |
内科学 | 11865篇 |
皮肤病学 | 1434篇 |
神经病学 | 4033篇 |
特种医学 | 3080篇 |
外科学 | 8218篇 |
综合类 | 797篇 |
一般理论 | 24篇 |
预防医学 | 2338篇 |
眼科学 | 1543篇 |
药学 | 4915篇 |
1篇 | |
中国医学 | 585篇 |
肿瘤学 | 4938篇 |
出版年
2023年 | 290篇 |
2022年 | 677篇 |
2021年 | 1617篇 |
2020年 | 854篇 |
2019年 | 1416篇 |
2018年 | 1592篇 |
2017年 | 1220篇 |
2016年 | 1525篇 |
2015年 | 2154篇 |
2014年 | 2565篇 |
2013年 | 2965篇 |
2012年 | 4421篇 |
2011年 | 4445篇 |
2010年 | 2688篇 |
2009年 | 2362篇 |
2008年 | 3345篇 |
2007年 | 3174篇 |
2006年 | 2920篇 |
2005年 | 2799篇 |
2004年 | 2426篇 |
2003年 | 2232篇 |
2002年 | 2016篇 |
2001年 | 1514篇 |
2000年 | 1414篇 |
1999年 | 1216篇 |
1998年 | 446篇 |
1997年 | 414篇 |
1996年 | 369篇 |
1995年 | 307篇 |
1994年 | 266篇 |
1993年 | 195篇 |
1992年 | 539篇 |
1991年 | 413篇 |
1990年 | 439篇 |
1989年 | 421篇 |
1988年 | 385篇 |
1987年 | 300篇 |
1986年 | 272篇 |
1985年 | 227篇 |
1984年 | 217篇 |
1983年 | 159篇 |
1982年 | 130篇 |
1981年 | 114篇 |
1980年 | 112篇 |
1979年 | 180篇 |
1978年 | 126篇 |
1977年 | 112篇 |
1975年 | 93篇 |
1974年 | 90篇 |
1972年 | 93篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
Chung‐Ying Lin Vida Imani Mark D. Griffiths Anders Brostrm Annette Nygrdh Zsolt Demetrovics Amir H. Pakpour 《Journal of sleep research》2021,30(1):e13076
The extant literature has suggested relationships between an individual's chronotype (in relation to morningness/eveningness) and several outcomes, including addictive disorders, psychological distress and daytime sleepiness. Moreover, sleep quality has been proposed to be a mediator in the aforementioned relationships. Consequently, the aim of the present study was to investigate the complex relationship between morningness/eveningness, problematic social media use, psychological distress and daytime sleepiness, with the potential mediators of sleep quality and insomnia. All participants (N = 1,791 [30.1% males]; mean age = 27.2 years, SD = 10.1) completed a battery of psychometric scales, including a reduced version of the Morningness‐Eveningness Questionnaire (at baseline), the Pittsburgh Sleep Quality Index and Insomnia Severity Index (1 month after baseline assessment), the Bergen Social Media Addiction Scale, the Hospital Anxiety and Depression Scale, and the Epworth Sleepiness Scale (2 months after baseline assessment). The impacts of morningness‐eveningness on problematic social media use, anxiety, depression and daytime sleepiness were found in the mediation models. Furthermore, the mediated effects of insomnia and sleep quality were observed. The present study's results emphasize the importance of promoting healthy sleep habits and sleep hygiene behaviours, and that of early detection of sleep problems among individuals who have the eveningness chronotype, because this would significantly improve their health outcomes. 相似文献
952.
953.
Chang Seok Lee Yung Hyup Joo Heung Soo Baek Miyoung Park Jeong‐Hwan Kim Hong‐Ju Shin Nok‐Hyun Park John Hwan Lee Young‐Ho Park Song Seok Shin Hae‐Kwang Lee 《Experimental dermatology》2016,25(1):44-49
Numerous medications are used to treat hyperpigmentation. However, several reports have indicated that repeated application of some agents, such as rhododendrol (RD), raspberry ketone (RK) and monobenzone (MB), can be toxic to melanocytes. Although these agents had severe side effects in human trials, no current in vitro methods can predict the safety of such drugs. This study assessed the in vitro effects of five depigmentary compounds including leukoderma‐inducing agents. In particular, we determined the effects of different concentrations and exposure times of different depigmentary agents on cell viability and melanogenesis in the presence and absence of ultraviolet B (UVB) radiation. Concentrations of RD, RK and MB that inhibit melanogenesis are similar to concentrations that are cytotoxic; however, concentrations of rucinol (RC) and AP736 that inhibit melanogenesis are much lower than concentrations that are cytotoxic. Furthermore, the concentrations that cause toxic effects depend on exposure duration, and prolonged exposure to RD, RK and MB had more cytotoxic effects than prolonged exposure to RC and AP736. The cytotoxic effects of RD and RK appear to be mediated by apoptosis due to increased expression of caspase‐3 and caspase‐8; UVB radiation increased the cytotoxicity of these agents and also increased caspase activity. Our results indicate that different leukoderma‐inducing compounds have different effects on the viability of normal epidermal melanocytes and suggest that the in vitro assay used here can be used to predict whether an investigational compound that induces leukoderma may lead to adverse effects in human trials. 相似文献
954.
Journal of Public Health - The first Covid-19 cases were reported in Malaysia on 25 January 2019 followed by a quiescent period before an upward swing of the cases at the end of February 2020,... 相似文献
955.
956.
957.
958.
959.
Dong Ho Park Tae Woo Kim Mo Se Kim Woong Han Da Eun Lee Gyu Seong Kim Chang Young Jeong 《The Journal of international medical research》2021,49(1)
Therapeutic hypothermia is often used for traumatic brain injury because of its neuroprotective effect and decreased secondary brain injury. However, this procedure lacks clinical evidence supporting its efficacy, and adverse outcomes have been reported during general anesthesia. A 61-year-old man with a history of percutaneous coronary intervention (PCI) was admitted with traumatic brain injury. Immediately after admission, he underwent mild therapeutic hypothermia with a target temperature of 33.0°C for neuroprotection. During general anesthesia for emergency surgery because he developed a mass effect, hypothermic cardiac arrest occurred following an additional decrease in the core body temperature. Moreover, myocardial infarction caused by restenosis of the previous PCI lesion also contributed to the cardiac arrest. Although the patient recovered spontaneous circulation after an hour-long cardiopulmonary resuscitation with rewarming, he eventually died of subsequent repetitive cardiac arrests. When anesthetizing patients undergoing therapeutic hypothermia, caution is required to prevent adverse outcomes that can be caused by unintentional severe hypothermia and exacerbation of underlying heart disease. 相似文献
960.