全文获取类型
收费全文 | 12968篇 |
免费 | 810篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 106篇 |
儿科学 | 246篇 |
妇产科学 | 237篇 |
基础医学 | 1172篇 |
口腔科学 | 94篇 |
临床医学 | 869篇 |
内科学 | 1728篇 |
皮肤病学 | 366篇 |
神经病学 | 925篇 |
特种医学 | 299篇 |
外科学 | 1119篇 |
综合类 | 300篇 |
现状与发展 | 3篇 |
预防医学 | 3837篇 |
眼科学 | 67篇 |
药学 | 1655篇 |
中国医学 | 14篇 |
肿瘤学 | 821篇 |
出版年
2024年 | 10篇 |
2023年 | 219篇 |
2022年 | 342篇 |
2021年 | 487篇 |
2020年 | 592篇 |
2019年 | 279篇 |
2018年 | 415篇 |
2017年 | 516篇 |
2016年 | 551篇 |
2015年 | 560篇 |
2014年 | 906篇 |
2013年 | 887篇 |
2012年 | 651篇 |
2011年 | 693篇 |
2010年 | 673篇 |
2009年 | 573篇 |
2008年 | 514篇 |
2007年 | 519篇 |
2006年 | 456篇 |
2005年 | 452篇 |
2004年 | 401篇 |
2003年 | 332篇 |
2002年 | 379篇 |
2001年 | 310篇 |
2000年 | 333篇 |
1999年 | 259篇 |
1998年 | 138篇 |
1997年 | 106篇 |
1996年 | 153篇 |
1995年 | 109篇 |
1994年 | 91篇 |
1993年 | 64篇 |
1992年 | 169篇 |
1991年 | 153篇 |
1990年 | 149篇 |
1989年 | 116篇 |
1988年 | 115篇 |
1987年 | 67篇 |
1986年 | 13篇 |
1985年 | 22篇 |
1984年 | 29篇 |
1983年 | 17篇 |
1982年 | 6篇 |
1981年 | 12篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1977年 | 3篇 |
1975年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
The presence of pesticides in the Israeli food supply is well documented but little is known about the risks posed by children's diets for potential exposures. We investigated potential exposures to food-borne pesticides in a sample of 301 urban Israeli children (2008–10). Data from a food frequency questionnaire, 24 hour food recall, and Israel's national pesticide monitoring program were used to estimate uptake factors for 26 compounds in 27 fruits and vegetables. A pilot risk assessment was performed and the findings were compared with the Israel Ministry of Health's 2012 pesticide risk assessment for the general population. The surveyed children had higher potential exposures than the general population for over one third of the compounds, and uptake factors exceeded the Acceptable Daily Intake in ten compounds. Methamidophos, exceeded the ADI at the 25th percentile and fenamiphos, iprodione, and oxydemethon methyl, exceeded the ADI at the 50 percentile. ADIs for several compounds were exceeded even though the residues detected were below the statutory limit. Improved monitoring, enforcement, and revision of the Maximum Residue Limit for certain food/pesticide pairs are indicated as is the need to incorporate data on children's actual food consumption in national risk assessments. 相似文献
23.
24.
25.
Kit Galvin Jen Krenz Marcy Harrington Pablo Palmández Richard A. Fenske 《Journal of agromedicine》2016,21(1):113-122
Development of the Practical Solutions for Pesticide Safety guide used participatory research strategies to identify and evaluate solutions that reduce pesticide exposures for workers and their families and to disseminate these solutions. Project principles were (1) workplace chemicals belong in the workplace, and (2) pesticide handlers and farm managers are experts, with direct knowledge of production practices. The project’s participatory methods were grounded in self-determination theory. Practical solutions were identified and evaluated based on five criteria: practicality, adaptability, health and safety, novelty, and regulatory compliance. Research activities that had more personal contact provided better outcomes. The Expert Working Group, composed of farm managers and pesticide handlers, was key to the identification of solutions, as were farm site visits. Audience participation, hands-on testing, and orchard field trials were particularly effective in the evaluation of potential solutions. Small work groups in a Regional Advisory Committee provided the best direction and guidance for a “user-friendly” translational document that provided evidence-based practical solutions. The “farmer to farmer” format of the guide was endorsed by both the Expert Working Group and the Regional Advisory Committee. Managers and pesticide handlers wanted to share their solutions in order to “help others stay safe,” and they appreciated attribution in the guide. The guide is now being used in educational programs across the region. The fundamental concept that farmers and farmworkers are innovators and experts in agricultural production was affirmed by this study. The success of this process demonstrates the value of participatory industrial hygiene in agriculture. 相似文献
26.
类鼻疽病是由类鼻疽伯克霍尔德菌(Burkholderia pseudomallei)感染引起的一类人畜共患病,主要流行于全球热带及亚热带地区。在我国主要流行于南部地区,疫源地为海南、广东、广西、台湾等。伴随着旅游业和贸易业的发展,我国其他非疫区出现了输入性病例。类鼻疽病的感染途径主要为经伤口、粘膜、呼吸道、消化道等,其病变可涉及机体所有器官,易造成较高的误诊率和病死率。然而我国目前类鼻疽病的流行病筛查技术存在一定的局限性,在防控方面未实行有效的疾病监测和疾病报告制度,对基层医师和民众疾病知识普及的力度不够。因此,本文旨在提高我国医务工作者对类鼻疽病的重视程度,从类鼻疽病的病原学特征、流行病学特征、临床特征、诊断与治疗、防控措施这五个方面进行详细综述。 相似文献
27.
ObjectiveMethamphetamine is used extensively around the world as a psychostimulant. The complications related to methamphetamine include methamphetamine-induced neurotoxicity, mainly involving intraneuronal processes, such as oxidative stress and excitotoxicity. Curcumin is effective against neuronal injury due to its antioxidant, anti-inflammatory effects. In this study, we examined the protective effects of curcumin against methamphetamine neurotoxicity.MethodsSixty male Wistar rats were divided into the following groups: control (n = 12), DMSO (n = 12), methamphetamine (n = 12), and methamphetamine + curcumin (100 and 200 mg/kg, respectively, intraperitoneal [IP]; n = 12). Neurotoxicity was induced by 40 mg/kg of methamphetamine administrated through 4 injections (4 × 10 mg/kg, q2h, IP). Curcumin (100 and 200 mg/kg) was administered at 7 days after the last methamphetamine injection. By using a Morris water maze task, the hippocampus-dependent memory and spatial learning were evaluated 1 day after the last curcumin injection. Then, the animal brains were isolated for biochemical measurements, as well as glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor protein-1(Iba-1) and caspase-3 immunohistochemical staining.ResultsThe current study demonstrated that administration of curcumin significantly attenuates spatial memory impairment (P < 0.01) following methamphetamine neurotoxicity. Curcumin caused a significant increase in the levels of superoxide dismutase and glutathione peroxidase (P < 0.05). However, it decreased tumor necrosis factor (TNF-α) (P < 0.05) and malondialdehyde (P < 0.01) levels as compared to the methamphetamine group. Also, curcumin significantly reduced Iba-1 (P < 0. 01), GFAP and caspase-3 positive cells in the hippocampus (P < 0.001).ConclusionCurcumin exerted neuroprotective effects on methamphetamine neurotoxicity because of its antioxidant and anti-inflammatory effect. 相似文献
28.
《The spine journal》2022,22(11):1759-1767
Despite the advances made in high-resolution spinal imaging, plain films (radiographs or x-rays) remain a cornerstone of evaluating and caring for spine patients in the preoperative, intraoperative, and postoperative settings. Although often undervalued when compared with more advanced imaging such as MRIs or CT scans, plain films provide surgeons invaluable information that other imaging modalities oftentimes cannot. In addition to their use during surgery for localization or evaluation of hardware placement, x-rays provide an overall image of a patient's spine, are useful in evaluating hardware complications, allow detailed assessment of alignment and stability and allow for repeated images in clinic during follow-up. Plain films continue to provide critical information that cannot be obtained with other imaging modalities, and they remain central to providing optimal care for spine patients. 相似文献
29.
《Journal of infection and chemotherapy》2020,26(1):128-131
Streptococcus pyogenes is a rare pathogen that causes endogenous endophthalmitis (EE). A healthy 58-year-old woman was diagnosed with EE secondary to septic arthritis caused by S. pyogenes. She underwent enucleation after hospitalization for 14 days with appropriate antibiotic cover. A literature search for outcomes of this condition revealed reports on only 10 eyes among 8 cases identified: 8 eyes (80%) developed poor visual outcome and 5 eyes (50%) underwent enucleation. There were no cases with immunocompromise. Our case report and literature review suggest the importance of awareness of the occurrence of S. pyogenes infection in immunocompetent hosts, and thus early diagnosis and aggressive treatment may be required to improve visual outcome. 相似文献
30.