全文获取类型
收费全文 | 14126篇 |
免费 | 1460篇 |
国内免费 | 162篇 |
专业分类
耳鼻咽喉 | 573篇 |
儿科学 | 275篇 |
妇产科学 | 111篇 |
基础医学 | 1387篇 |
口腔科学 | 238篇 |
临床医学 | 1001篇 |
内科学 | 1052篇 |
皮肤病学 | 349篇 |
神经病学 | 834篇 |
特种医学 | 847篇 |
外科学 | 977篇 |
综合类 | 793篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 4908篇 |
眼科学 | 194篇 |
药学 | 1734篇 |
2篇 | |
中国医学 | 42篇 |
肿瘤学 | 429篇 |
出版年
2024年 | 18篇 |
2023年 | 209篇 |
2022年 | 347篇 |
2021年 | 624篇 |
2020年 | 648篇 |
2019年 | 560篇 |
2018年 | 534篇 |
2017年 | 657篇 |
2016年 | 597篇 |
2015年 | 572篇 |
2014年 | 799篇 |
2013年 | 1327篇 |
2012年 | 687篇 |
2011年 | 797篇 |
2010年 | 592篇 |
2009年 | 605篇 |
2008年 | 637篇 |
2007年 | 578篇 |
2006年 | 537篇 |
2005年 | 497篇 |
2004年 | 409篇 |
2003年 | 345篇 |
2002年 | 285篇 |
2001年 | 275篇 |
2000年 | 278篇 |
1999年 | 183篇 |
1998年 | 199篇 |
1997年 | 166篇 |
1996年 | 195篇 |
1995年 | 171篇 |
1994年 | 149篇 |
1993年 | 124篇 |
1992年 | 152篇 |
1991年 | 133篇 |
1990年 | 126篇 |
1989年 | 96篇 |
1988年 | 81篇 |
1987年 | 72篇 |
1986年 | 43篇 |
1985年 | 84篇 |
1984年 | 77篇 |
1983年 | 51篇 |
1982年 | 54篇 |
1981年 | 42篇 |
1980年 | 32篇 |
1979年 | 27篇 |
1978年 | 18篇 |
1977年 | 21篇 |
1976年 | 17篇 |
1973年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
N. Cody Schaal Raushan A. Salaam Michael Stevens Alex Stubner 《Journal of occupational and environmental hygiene》2019,16(5):329-335
The purpose of this investigation was to characterize noise levels in spaces designated as “effective quiet” areas on a U.S. Navy aircraft carrier. Noise dosimetry samples were collected in 15 designated spaces, representing 15 noise measurements, while at-sea during airwing carrier qualifications. Equivalent sound level (Leq) measurements were collected during flight operations (Leq (flt ops)), non-flight operations (Leq (non-flt ops)), and over 24-hr periods (Leq (24-hr)). These data were compared to the 70 dBA American Conference of Governmental Industrial Hygienists (ACGIH®) Threshold Limit Value (TLV®) for “effective quiet” areas intended for temporary threshold shift recovery when personnel live and work in a potentially noise hazardous environment for periods greater than 24?hr. The monitored areas were selected based on personnel occupancy/use during off-duty time periods. Areas were classified by either (1) leisure areas that included mess (eating areas), gyms, lounges, an internet cafe, and the fantail social area or (2) berthing (sleeping) areas. The Leq measurements in decibels “A” weighted (dBA) were compared to determine significant differences between Leq (flt ops), Leq (non-flt ops), and Leq (24-hr) and were compared between leisure area and berthing area. Measured noise levels according to time period ranged as follows: (1) Leq (24-hr): 70.8–105.4 dBA; (2) Leq (flt ops): 70–101.2 dBA; and (3) Leq (non-flt ops): 39.4–104.6 dBA. All area measurements over the 24-hr period and during flight operations and 46.7% of the areas during the non-flight operation time period exceeded the “effective quiet” 70 dBA ACGIH TLV. Mean Leqs were 15 dBA higher during flight operations compared to non-flight operations in “effective quiet” areas (p?=?0.001). The Leqs in leisure areas were significantly higher than berthing areas by approximately 21 dBA during non-flight operation periods (p?=?0.001). Results suggest noise levels in “effective quiet” areas frequented by aircraft carrier personnel during off-duty hours when at-sea may inhibit auditory recovery from occupational noise exposures that occur on-duty. 相似文献
2.
3.
《Journal of vascular and interventional radiology : JVIR》2020,31(6):869-875
This paper describes country-wide special measures undertaken for interventional radiology staff during the current coronavirus disease 2019 (COVID-19) pandemic. Although each interventional radiology service around the world faces unique challenges, the principles outlined in this article will be useful when designing or strengthening individual practices and integrating them within wider hospital and national measures. Moving beyond the current outbreak, these measures will be useful for any future infectious diseases which are likely to arise. 相似文献
4.
Jae Yun Ahn Jung Bae Park Sungbae Moon Jae Wan Cho Dong Ho Park 《Ophthalmic epidemiology》2020,27(2):105-114
ABSTRACT
Purpose
Work-related eye injuries have been reported with a variety of epidemiologic and clinical characteristics. We aimed to identify epidemiologic characteristics of work-related eye injuries and risk factors associated with severe injury in a large metropolitan city. 相似文献5.
6.
7.
Maaike van Gerwen MD Naomi Alpert MS Raja Flores MD Emanuela Taioli MD PhD 《American journal of industrial medicine》2020,63(2):115-120
The association between asbestos exposure, mainly in occupational settings, and malignant mesothelioma has been well established; this has prompted several countries to establish mesothelioma epidemiologic surveillance programs often at the request of national agencies. This review compares currently existing mesothelioma registries worldwide to develop a concept model for a US real-time case capture mesothelioma registry. Five countries were identified with a mesothelioma specific registry, including Italy, France, UK, Australia, and South Korea. All, except the UK, used interviews to collect exposure data. Linkage with the national death index was available or was in future plans for all registries. The registries have limited information on treatment, quality of life, and other patient-centered outcomes such as symptoms and pain management. To thoroughly collect exposure data, “real-time” enrollment is preferable; to maximize the capture of mesothelioma cases, optimal coverage, and a simplified consent process are needed. 相似文献
8.
9.
BackgroundPrior reports demonstrate the expression of estrogen and progesterone receptors in high-grade gliomas (HGGs), but the relationship between hormone receptor-positive disease and risk of HHGs in patients with breast cancer (BC) remains uncharacterized.MethodsUsing the SEER 18 registries (2000–2017), we examined the temporal trend of the incidence of HGGs and BC. The standardized incidence ratio was calculated to assess the risk of subsequent HGG in BC patients.ResultsDuring the study period, the incidence of BC and HGGs remained comparable for men and women. Among 976,134 patients with BC, we found a decreased incidence of HGGs in females, but not in males. Female BC patients with hormone receptor-positive disease were at a lower risk of developing glioblastoma and anaplastic astrocytoma.ConclusionOur study findings allude to the protective role of hormone exposure in the development of HGGs, which may lead to the development of therapies targeting hormonal pathways. 相似文献
10.
《European annals of otorhinolaryngology, head and neck diseases》2022,139(1):21-27
ObjectivesThis document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs.Material and methodsThe recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence.ResultsEight tests of speech audiometry in noise can be used in France.ConclusionTo be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other). 相似文献