全文获取类型
收费全文 | 34555篇 |
免费 | 1550篇 |
国内免费 | 439篇 |
专业分类
耳鼻咽喉 | 262篇 |
儿科学 | 904篇 |
妇产科学 | 536篇 |
基础医学 | 2065篇 |
口腔科学 | 415篇 |
临床医学 | 3104篇 |
内科学 | 6546篇 |
皮肤病学 | 482篇 |
神经病学 | 1198篇 |
特种医学 | 749篇 |
外国民族医学 | 1篇 |
外科学 | 3397篇 |
综合类 | 4610篇 |
一般理论 | 3篇 |
预防医学 | 3234篇 |
眼科学 | 322篇 |
药学 | 4077篇 |
31篇 | |
中国医学 | 3753篇 |
肿瘤学 | 855篇 |
出版年
2024年 | 65篇 |
2023年 | 307篇 |
2022年 | 621篇 |
2021年 | 1064篇 |
2020年 | 872篇 |
2019年 | 2928篇 |
2018年 | 2376篇 |
2017年 | 1649篇 |
2016年 | 680篇 |
2015年 | 670篇 |
2014年 | 1802篇 |
2013年 | 1697篇 |
2012年 | 1761篇 |
2011年 | 1581篇 |
2010年 | 1343篇 |
2009年 | 1179篇 |
2008年 | 1096篇 |
2007年 | 1078篇 |
2006年 | 896篇 |
2005年 | 732篇 |
2004年 | 549篇 |
2003年 | 540篇 |
2002年 | 402篇 |
2001年 | 367篇 |
2000年 | 263篇 |
1999年 | 209篇 |
1998年 | 200篇 |
1997年 | 162篇 |
1996年 | 137篇 |
1995年 | 165篇 |
1994年 | 142篇 |
1993年 | 69篇 |
1992年 | 84篇 |
1991年 | 72篇 |
1990年 | 65篇 |
1988年 | 52篇 |
1986年 | 59篇 |
1985年 | 667篇 |
1984年 | 1094篇 |
1983年 | 811篇 |
1982年 | 822篇 |
1981年 | 807篇 |
1980年 | 738篇 |
1979年 | 716篇 |
1978年 | 644篇 |
1977年 | 437篇 |
1976年 | 550篇 |
1975年 | 443篇 |
1974年 | 425篇 |
1973年 | 346篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Heather L. Brown 《Journal of emergency nursing》2021,47(2):321-325
The coronavirus 2019 pandemic has affected almost every aspect of health care delivery in the United States, and the emergency medicine system has been hit particularly hard while dealing with this public health crisis. In an unprecedented time in our history, medical systems and clinicians have been asked to be creative, flexible, and innovative, all while continuing to uphold the important standards in the US health care system. To continue providing quality services to patients during this extraordinary time, care providers, organizations, administrators, and insurers have needed to alter longstanding models and procedures to respond to the dynamics of a pandemic. The Emergency Medicine Treatment and Active Labor Act of 1986, or EMTALA, is 1 example of where these alterations have allowed health care facilities and clinicians to continue their work of caring for patients while protecting both the patients and the clinicians themselves from infectious exposures at the same time. 相似文献
2.
《Research in social & administrative pharmacy》2022,18(9):3694-3698
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area. 相似文献
3.
《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases. 相似文献
4.
5.
6.
《Journal of pharmaceutical sciences》2019,108(11):3515-3520
Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed. 相似文献
7.
通过对中医古籍中有关升降散论述的文献梳理,全面探讨其内涵。本方是在大黄、僵蚕为雏形的基础上增加蝉蜕、姜黄而成方,几经易名,终在杨璿《伤寒瘟疫条辨》中为后人所熟知。本方广泛用于治疗瘟疫,以丸剂、散剂为主,方便携带,便于服用;重用大黄旨在祛邪、逐秽;应用时视人之体质强弱和量其毒之轻重而判断用药多寡,并辅以米酒、生蜜等以顾护正气。杨璿将其由治疗“热疫”的专方扩展为治疗“表里三焦大热”的通用方剂,扩大了本方治疗疾病范围。 相似文献
8.
9.
10.
《Biomaterials》2015
A combination of various therapeutic approaches has emerged as a promising strategy for cancer treatment. A safe and competent nano-delivery system is thus in urgent demand to facilitate the simultaneous transport of various therapeutic agents to cancer cells and a tumor region to achieve synergistic effect. Gold nanoparticles (GNPs) and mesoporous silica nanoparticle (MSNs) were fabricated herein as potential candidates for drug delivery. Serving as gatekeepers, GNPs (5 nm in diameter) were attached onto the amino-functionalized MSNs (denoted as NMSNs) via a relatively weak gold–nitrogen bonding. The resulting nanohybrids (denoted as GCMSNs) were uptaken by cells, and the detachment of GNPs and subsequent intracellular drug release from NMSNs were achieved by competitive binding of intracellular glutathione to GNPs. In addition to the function of gatekeeping, GNPs also play another role as the oxidative stress elicitor. Our in vitro studies revealed that GCMSNs induced higher oxidative stress in lung cancer cells (A549) than in normal cells (3T3-L1). This growth inhibitory effect found in the cancer cells was likely induced by mitochondria dysfunction originated from the GCMSN-induced, oxidative stress-triggered mitochondria-mediated autophagy. The redox-responsive nanohybrids were further loaded with camptothecin and the intensified synergistic therapeutic effects were observed associated with combined chemotherapy and oxidative stress strategy. The results clearly demonstrate that such unique nanohybrids hold great promise for selective and effective cancer treatments. 相似文献