全文获取类型
收费全文 | 6582篇 |
免费 | 619篇 |
国内免费 | 269篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 40篇 |
妇产科学 | 13篇 |
基础医学 | 326篇 |
口腔科学 | 248篇 |
临床医学 | 997篇 |
内科学 | 650篇 |
皮肤病学 | 27篇 |
神经病学 | 390篇 |
特种医学 | 82篇 |
外科学 | 206篇 |
综合类 | 728篇 |
一般理论 | 1篇 |
预防医学 | 687篇 |
眼科学 | 39篇 |
药学 | 2010篇 |
7篇 | |
中国医学 | 929篇 |
肿瘤学 | 68篇 |
出版年
2024年 | 9篇 |
2023年 | 124篇 |
2022年 | 149篇 |
2021年 | 320篇 |
2020年 | 279篇 |
2019年 | 354篇 |
2018年 | 262篇 |
2017年 | 322篇 |
2016年 | 287篇 |
2015年 | 273篇 |
2014年 | 468篇 |
2013年 | 781篇 |
2012年 | 474篇 |
2011年 | 409篇 |
2010年 | 259篇 |
2009年 | 270篇 |
2008年 | 287篇 |
2007年 | 296篇 |
2006年 | 271篇 |
2005年 | 227篇 |
2004年 | 198篇 |
2003年 | 168篇 |
2002年 | 131篇 |
2001年 | 131篇 |
2000年 | 86篇 |
1999年 | 69篇 |
1998年 | 62篇 |
1997年 | 66篇 |
1996年 | 56篇 |
1995年 | 49篇 |
1994年 | 32篇 |
1993年 | 41篇 |
1992年 | 39篇 |
1991年 | 21篇 |
1990年 | 22篇 |
1989年 | 26篇 |
1988年 | 19篇 |
1987年 | 12篇 |
1986年 | 10篇 |
1985年 | 16篇 |
1984年 | 19篇 |
1983年 | 13篇 |
1982年 | 13篇 |
1981年 | 10篇 |
1980年 | 10篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1974年 | 2篇 |
排序方式: 共有7470条查询结果,搜索用时 31 毫秒
1.
《Journal of the American Medical Directors Association》2022,23(11):1861-1867
ObjectivesOlder adults' prior health status can influence their recovery after a major illness. We investigated the association between older adults’ independence in self-care tasks prior to a skilled nursing facility (SNF) stay and their self-care function at SNF admission, discharge, and the change in self-care function during an SNF stay.DesignRetrospective study of 100% national CMS data files from October 1, 2018, to December 31, 2019.Settings and ParticipantsThe sample included 616,073 Medicare fee-for-service beneficiaries who were discharged from an SNF between October 1, 2018, and December 31, 2019.MethodsThe admission Minimum Data Set (MDS) was used to determine residents’ prior ability (independent, some help, dependent) to complete self-care tasks before the current illness, exacerbation, or injury. Seven self-care tasks from MDS Section GG were used to calculate total scores (range 7-42 points) for self-care at admission, discharge, and the change in self-care between admission and discharge.ResultsMost residents (62.0%) were independent, 35.3% needed some help, and 2.64% were dependent in self-care prior to SNF admission. Nearly 25% of residents with urinary incontinence, 28.8% with bowel incontinence, and 31.7% with moderate-severe cognitive impairment were independent in self-care prior to SNF admission compared with approximately 70% of residents without these conditions. Compared with residents who were dependent in self-care prior to SNF admission, those who were independent or needed some help had significantly higher self-care total scores at admission (5.67 vs 4.21 points, respectively) and discharge (6.44 vs 3.82 points, respectively) and exhibited greater improvement in self-care (3.48 vs 1.62 points, respectively).Conclusions and ImplicationsOur findings are evidence that the new MDS item for a resident's independence in self-care tasks before SNF admission is a valid measure of their prior self-care function. This is clinically useful information and should be considered when developing rehabilitation goals. 相似文献
2.
3.
4.
Kevin W. Wellington Nomgqibelo B. P. Nyoka Lyndy J. McGaw 《Drug development research》2019,80(3):386-394
The WHO has stated that antibiotic resistance is escalating to perilously high levels globally and that traditional therapies of antimicrobial drugs are futile against infections caused by resistant microorganisms. Novel antimicrobial drugs are therefore required. We report in this study on the inhibitory activity of the 1,4-naphthoquinone-2,3-bis-sulfides and 1,4-naphthoquinone sulfides against two bacteria and a fungus to determine their antimicrobial properties. The 1,4-naphthoquinone sulfides have potent activity with a minimum inhibitory concentration (MIC) of 7.8 μg/mL against Staphylococcus aureus (Gram +ve), an MIC of 23.4 μg/mL against the fungus, Candida albicans, which was better than that of Amphotericin B (MIC = 31.3 μg/mL), and against Escherichia coli (Gram −ve) an MIC of 31.3 μg/mL was obtained. The 1,4-naphthoquinone had an MIC of 11.7 μg/mL against S. aureus and the 1,4-naphthohydroquinone also had the same activity against E. coli.
相似文献
Hit, Lead & Candidate Discovery |
5.
6.
Marta López-Fauqued Laura Campora Frédérique Delannois Mohamed El Idrissi Lidia Oostvogels Ferdinandus J. De Looze Javier Diez-Domingo Thomas C. Heineman Himal Lal Janet E. McElhaney Shelly A. McNeil Wilfred Yeo Fernanda Tavares-Da-Silva 《Vaccine》2019,37(18):2482-2493
Background
The ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials showed that the adjuvanted recombinant zoster vaccine (RZV) was ≥90% efficacious in preventing herpes zoster in adults. Here we present a comprehensive overview of the safety data from these studies.Methods
Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomly vaccinated with RZV or placebo. Safety analyses were performed on the pooled total vaccinated cohort, consisting of participants receiving at least one dose of RZV or placebo. Solicited and unsolicited adverse events (AEs) were collected for 7 and 30?days after each vaccination, respectively. Serious AEs (SAEs) were collected from the first vaccination until 12?months post-last dose. Fatal AEs, vaccination-related SAEs, and potential immune-mediated diseases (pIMDs) were collected during the entire study period.Results
Safety was evaluated in 14,645 RZV and 14,660 placebo recipients. More RZV than placebo recipients reported unsolicited AEs (50.5% versus 32.0%); the difference was driven by transient injection site and solicited systemic reactions that were generally seen in the first week post-vaccination. The occurrence of overall SAEs (RZV: 10.1%; Placebo: 10.4%), fatal AEs (RZV: 4.3%; Placebo: 4.6%), and pIMDs (RZV: 1.2%; Placebo: 1.4%) was balanced between groups. The occurrence of possible exacerbations of pIMDs was rare and similar between groups. Overall, except for the expected local and systemic symptoms, the safety results were comparable between the RZV and Placebo groups irrespective of participant age, gender, or race.Conclusions
No safety concerns arose, supporting the favorable benefit-risk profile of RZV. 相似文献7.
目的:建立大黄特征化学成分和抗氧化活性相关联的二维指纹图谱,研究大黄抗氧化活性物质。方法:利用高效液相多检测器联用的抗氧化活性成分在线检测体系,对大黄中化学成分进行检测,共鉴定出大黄中化学成分15种;其中8种具有抗氧化活性;然后采用清除效率为指标对各活性成分的抗氧化活性进行评价。结果:结果发现化合物葡萄糖紫丁香酸、腺嘌呤、没食子酸、儿茶素或表儿茶素、双花母草素、2-O-桂皮酰-没食子酰葡萄糖等具有较强的清除ABTS·+的活性,而蒽醌类成分对ABTS·+的清除作用较弱。结论:采用HPLC-ABTS-DAD-Q-TOF/MS对大黄中的抗氧化活性成分进行快速分析鉴定,初步阐明大黄在抗氧化环节起作用的效应物质。 相似文献
8.
These guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of post‐operative surgical site infections (SSIs) in solid organ transplantation. SSIs are a significant cause of morbidity and mortality in SOT recipients. Depending on the organ transplanted, SSIs occur in 3%‐53% of patients, with the highest rates observed in small bowel/multivisceral, liver, and pancreas transplant recipients. These infections are classified by increasing invasiveness as superficial incisional, deep incisional, or organ/space SSIs. The spectrum of organisms implicated in SSIs in SOT recipients is more diverse than the general population due to other important factors such as the underlying end‐stage organ failure, immunosuppression, prolonged hospitalizations, organ transportation/preservation, and previous exposures to antibiotics in donors and recipients that could predispose to infections with multidrug‐resistant organisms. In this guideline, we describe the epidemiology, clinical presentation, differential diagnosis, potential pathogens, and management. We also provide recommendations for the selection, dosing, and duration of peri‐operative antibiotic prophylaxis to minimize post‐operative SSIs. 相似文献
9.
10.
夹竹桃科(Apocynaceae)狗牙花属(Ervatamia Stapf)植物中的化学成分以及其生物活性一直是研究热点。其在全世界有约120种,主要分布在印度、中国西南地区,东南亚、大洋洲、北美洲、南美洲部分地区以及各海岛;在我国主要有15种和5变种,主要分布在华南地区及西南地区和台湾。我国傣族将云南狗牙花茎用于治疗产后体虚、头晕目眩、恶露淋漓等症状。据《中国植物志》中记载,产于亚洲热带与亚热带地区的单瓣狗牙花,其叶有降低血压功效,常用于治眼病、疮疥、乳疮、咬伤等;根可治头痛和骨折等。生物碱是狗牙花属植物中的主要化学成分,具有新颖的化学结构。现代药理学研究发现,狗牙花属植物中生物碱类成分具有抗肿瘤和抗乙酰胆碱脂酶等生物活性,其中抗肿瘤活性最为显著。因此狗牙花属植物具有很好的开发价值。但是,科研人员对狗牙花属植物生物碱类成分的研究仅限于发现与生物活性的测定,临床功效的研究较少。笔者结合近20年来的国内外文献对该属植物中149个生物碱进行总结,为进一步研究具有显著活性的生物碱类化学成分,合理充分利用狗牙花属植物的药用资源提供有价值的参考。 相似文献