全文获取类型
收费全文 | 308184篇 |
免费 | 18180篇 |
国内免费 | 437篇 |
专业分类
耳鼻咽喉 | 4635篇 |
儿科学 | 11367篇 |
妇产科学 | 10690篇 |
基础医学 | 45677篇 |
口腔科学 | 8319篇 |
临床医学 | 25034篇 |
内科学 | 57856篇 |
皮肤病学 | 6623篇 |
神经病学 | 21820篇 |
特种医学 | 12164篇 |
外国民族医学 | 43篇 |
外科学 | 49295篇 |
综合类 | 7908篇 |
现状与发展 | 1篇 |
一般理论 | 167篇 |
预防医学 | 20317篇 |
眼科学 | 7331篇 |
药学 | 21793篇 |
中国医学 | 853篇 |
肿瘤学 | 14908篇 |
出版年
2021年 | 2432篇 |
2019年 | 2458篇 |
2018年 | 4022篇 |
2017年 | 3011篇 |
2016年 | 3512篇 |
2015年 | 3798篇 |
2014年 | 5039篇 |
2013年 | 7882篇 |
2012年 | 9804篇 |
2011年 | 10318篇 |
2010年 | 6609篇 |
2009年 | 5821篇 |
2008年 | 9460篇 |
2007年 | 10301篇 |
2006年 | 10159篇 |
2005年 | 9741篇 |
2004年 | 9503篇 |
2003年 | 8944篇 |
2002年 | 8510篇 |
2001年 | 13689篇 |
2000年 | 14060篇 |
1999年 | 11662篇 |
1998年 | 3102篇 |
1997年 | 2869篇 |
1996年 | 2711篇 |
1995年 | 2578篇 |
1992年 | 8333篇 |
1991年 | 8464篇 |
1990年 | 8269篇 |
1989年 | 8087篇 |
1988年 | 7323篇 |
1987年 | 7084篇 |
1986年 | 6726篇 |
1985年 | 6521篇 |
1984年 | 4767篇 |
1983年 | 4121篇 |
1982年 | 2474篇 |
1979年 | 4433篇 |
1978年 | 3231篇 |
1977年 | 2740篇 |
1976年 | 2503篇 |
1975年 | 2836篇 |
1974年 | 3362篇 |
1973年 | 3368篇 |
1972年 | 3124篇 |
1971年 | 2952篇 |
1970年 | 2840篇 |
1969年 | 2583篇 |
1968年 | 2541篇 |
1967年 | 2377篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Mehmet Varol Kadriye Benkli Ayşe T. Koparal Rakibe B. Bostancıoğlu 《Drug and chemical toxicology》2019,42(4):436-443
Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types. 相似文献
72.
73.
Christopher N. Cooley Tyler J. Beranek Matthew A. Warpinski Robert Alexander Amanda O. Esquivel 《The American journal of emergency medicine》2019,37(2):199-203
Introduction
In the United States there has been a large increase in participation in lacrosse for both males and females. The purpose of this study was to analyze the number of head injuries, injury rates (calculated using the reported number of participants) and types of head injuries that are seen in emergency departments in the United States.Methods
We compared injuries between male and female lacrosse participants. This was a retrospective study using a publicly available database produced by the US Consumer Product Safety Commission and information about lacrosse participation from US Lacrosse.Results
A linear regression was performed and showed a positive correlation between number of head injuries to males and time from 2002 to 2010 (R2?=?0.823; p?=?0.001). While the number of injuries to the head in female lacrosse participants was not significant. There was a negative correlation between the number of head injuries to males from 2010 to 2016 (R2?=?0.800; p?=?0.007), but again, there was no significance for female injury count (R2?=?0.417; p?=?0.117). Other significant differences between head injuries in males and females included the mechanism of injury and the type of injury recorded.Conclusion
The most recent data from 2010 to 2016, suggest that both males and females have had a decrease in injury rate. However the total number of female head injuries is not significantly decreasing and as the sport continues to grow there will likely be more total head injuries and visits to the emergency department. 相似文献74.
M. Masson Regnault J. Castañeda-Sanabria M.H.T. Diep Tran M. Beylot-Barry H. Bachelez N. Beneton O. Chosidow A. Dupuy P. Joly D. Jullien E. Mahé M.-A. Richard M. Viguier F. Tubach E. Sbidian C. Paul The PsoBioTeq Study Group 《Journal of the European Academy of Dermatology and Venereology》2020,34(2):293-300
75.
76.
Philippe A. Eigenmann Motohiro Ebisawa Matthew Greenhawt Jonathan O’B Hourihane Tamara T. Perry Benjamin C. Remington Robert A. Wood 《Pediatric allergy and immunology》2021,32(4):658-666
Risk is a concept inherent in every medical procedure. It can be defined as the probability of an adverse event in a defined population over a specified period of time. In the frame of food allergy management, it might be related to a diagnostic procedure, a treatment, or the consumption of foods. The risk of an adverse event can also be augmented by individual factors. This rostrum article discusses various aspects faced by children with food allergies in the light of risk, and their practical implications. Identifying personal risks for severe reaction, such as unstable asthma, and correcting them whenever possible also contribute to a reduction of the risk inherent to food allergy. Among the facets discussed, oral food challenges (OFC) are the most common diagnostic procedures implying an inherent risk. The risk of OFCs can be minimized by correct indication and timing of the test, a safe setting, as well as by ensuring that the patient is otherwise well without potential stressor potentially increasing the risk of a more severe reaction. Oral immunotherapy (OIT) has been studied as a potential treatment for increasing the threshold dose for reaction, and thus reducing the risk of accidental reaction. Nevertheless, the procedure is not devoid of risk as the patients may and do often react during the course of the procedure. Ingestion of trace amounts in processed foods, mainly in community settings such as restaurants, schools, or day care, represents a potential risk of reactions, although for a minority of patients. Precautionary allergen labeling (PAL) is a widespread strategy to reduce the potential risk of reactions due to traces. However, PAL is currently inefficient due to inconsistent labeling, also not indicating a clear maximum amount possibly present in the manufactured food. Finally, cost-effectiveness needs to be considered in risk management, as many risk reduction procedures are clearly not cost-effective. 相似文献
77.
78.
79.
80.
Pretibial lacerations and lower limb wounds are referred to plastic surgery teams for split skin graft surgery. Traditionally, these patients have been immobilised on bedrest following surgery. More recently, patients have commenced ambulation earlier to avoid medical complications and facilitate discharge. The objective of this literature review was to determine when such patients should begin walking. A literature search was undertaken using the electronic databases AMED, Cinahl, Embase, Medline (via Ovid), PEDro and Pubmed. Clinical trials using human subjects, written in English, were included. Seventeen (of 1137) papers met the inclusion criteria and were reviewed. The literature suggested that patients should begin walking immediately or at the earliest possible opportunity after lower limb skin graft surgery. Although the literature advocated early ambulation, the evidence base presented with a number of recurrent methodological limitations, including small sample sizes, lack of a control sample, and limited follow-up. Accordingly, further research employing large, well-designed, randomised controlled trials is recommended. It will then be possible to understand with greater certainty when patients should begin walking after lower extremity split skin graft surgery. 相似文献