全文获取类型
收费全文 | 1899篇 |
免费 | 276篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 60篇 |
妇产科学 | 30篇 |
基础医学 | 122篇 |
口腔科学 | 76篇 |
临床医学 | 285篇 |
内科学 | 499篇 |
皮肤病学 | 39篇 |
神经病学 | 85篇 |
特种医学 | 309篇 |
外科学 | 193篇 |
综合类 | 21篇 |
预防医学 | 312篇 |
眼科学 | 11篇 |
药学 | 41篇 |
肿瘤学 | 102篇 |
出版年
2023年 | 50篇 |
2022年 | 14篇 |
2021年 | 21篇 |
2020年 | 44篇 |
2019年 | 20篇 |
2018年 | 57篇 |
2017年 | 41篇 |
2016年 | 53篇 |
2015年 | 64篇 |
2014年 | 107篇 |
2013年 | 129篇 |
2012年 | 57篇 |
2011年 | 58篇 |
2010年 | 81篇 |
2009年 | 92篇 |
2008年 | 61篇 |
2007年 | 85篇 |
2006年 | 64篇 |
2005年 | 46篇 |
2004年 | 47篇 |
2003年 | 27篇 |
2002年 | 25篇 |
2001年 | 36篇 |
2000年 | 34篇 |
1999年 | 37篇 |
1998年 | 71篇 |
1997年 | 95篇 |
1996年 | 81篇 |
1995年 | 60篇 |
1994年 | 62篇 |
1993年 | 53篇 |
1992年 | 18篇 |
1991年 | 16篇 |
1990年 | 34篇 |
1989年 | 46篇 |
1988年 | 34篇 |
1987年 | 36篇 |
1986年 | 36篇 |
1985年 | 32篇 |
1984年 | 14篇 |
1983年 | 14篇 |
1982年 | 25篇 |
1981年 | 32篇 |
1980年 | 18篇 |
1979年 | 8篇 |
1978年 | 6篇 |
1977年 | 15篇 |
1976年 | 17篇 |
1975年 | 10篇 |
1969年 | 4篇 |
排序方式: 共有2198条查询结果,搜索用时 15 毫秒
81.
Mark JD Jordans Wietse A Tol Ivan H Komproe Dessy Susanty Anavarathan Vallipuram Prudence Ntamatumba Amin C Lasuba Joop TVM de Jong 《International journal of mental health systems》2010,4(1):15
Few psychosocial and mental health care systems have been reported for children affected by political violence in low- and
middle income settings and there is a paucity of research-supported recommendations. This paper describes a field tested multi-layered
psychosocial care system for children (focus age between 8-14 years), aiming to translate common principles and guidelines
into a comprehensive support package. This community-based approach includes different overlapping levels of interventions
to address varying needs for support. These levels provide assessment and management of problems that range from the social-pedagogic
domain to the psychosocial, the psychological and the psychiatric domains. Specific intervention methodologies and their rationale
are described within the context of a four-country program (Burundi, Sri Lanka, Indonesia and Sudan). The paper aims to contribute
to bridge the divide in the literature between guidelines, consensus & research and clinical practice in the field of psychosocial
and mental health care in low- and middle-income countries. 相似文献
82.
The effect of PGI2 and theophylline on the response of platelets subjected to shear stress 总被引:2,自引:0,他引:2
A specially designed rotational viscometer was used to investigate the effects of the antiplatelet agent PGI2 in combination with theophylline on the response of human platelets subjected to shear stress. Samples of citrated platelet-rich plasma (PRP) were exposed to shear stress in the viscometer for a period of 5 min at 23 degrees C. The levels of stress studied ranged from 50 to 300 dynes/sq cm. Pretreatment of the platelets with 0.01 microM PGI2 and 500 microM theophylline before exposure to shear stress caused a large reduction in shear-induced platelet aggregation. However, it was also observed that the PGI2-- theophylline pretreatment concomitantly caused a large increase in shear-induced platelet lysis and serotonin release at stress levels equal to or greater than 150 dynes/sq cm. This observed increase in platelet fragility may have important implications for clinical applications of PGI2. The results are discussed and compared to those obtained in prior work in which platelets were pretreated with acetylsalicylic acid or with PGE1. 相似文献
83.
84.
85.
Impact of Breast Density Legislation on Breast Cancer Risk Assessment and Supplemental Screening: A Survey of 110 Radiology Facilities 下载免费PDF全文
Lina Nayak MD Kanae K. Miyake MD PhD Jessica W. T. Leung MD Elissa R. Price MD Yueyi I. Liu MD PhD Bonnie N. Joe MD PhD Edward A. Sickles MD William R. Thomas MD Jafi A. Lipson MD Bruce L. Daniel MD Jonathan Hargreaves MD R. James Brenner MD JD Lawrence W. Bassett MD Haydee Ojeda‐Fournier MD Karen K. Lindfors MD MPH Stephen A. Feig MD Debra M. Ikeda MD 《The breast journal》2016,22(5):493-500
Breast density notification laws, passed in 19 states as of October 2014, mandate that patients be informed of their breast density. The purpose of this study is to assess the impact of this legislation on radiology practices, including performance of breast cancer risk assessment and supplemental screening studies. A 20‐question anonymous web‐based survey was emailed to radiologists in the Society of Breast Imaging between August 2013 and March 2014. Statistical analysis was performed using Fisher's exact test. Around 121 radiologists from 110 facilities in 34 USA states and 1 Canadian site responded. About 50% (55/110) of facilities had breast density legislation, 36% of facilities (39/109) performed breast cancer risk assessment (one facility did not respond). Risk assessment was performed as a new task in response to density legislation in 40% (6/15) of facilities in states with notification laws. However, there was no significant difference in performing risk assessment between facilities in states with a law and those without (p < 0.831). In anticipation of breast density legislation, 33% (16/48), 6% (3/48), and 6% (3/48) of facilities in states with laws implemented handheld whole breast ultrasound (WBUS), automated WBUS, and tomosynthesis, respectively. The ratio of facilities offering handheld WBUS was significantly higher in states with a law than in states without (p < 0.001). In response to breast density legislation, more than 33% of facilities are offering supplemental screening with WBUS and tomosynthesis, and many are performing formal risk assessment for determining patient management. 相似文献
86.
Moore AD; Godwin JD; Muller NL; Naidich DP; Hammar SP; Buschman DL; Takasugi JE; de Carvalho CR 《Radiology》1989,172(1):249-254
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities. 相似文献
87.
The authors report 2.5 years' experience with the use of cytomegalovirus (CMV)-seronegative blood components for the prevention of primary CMV infection after allogeneic marrow transplantation from seronegative marrow donors to 104 CMV-seronegative patients. Patients and blood donors were screened for CMV-seronegativity by a combination of passive latex agglutination, complement fixation, and indirect hemagglutination CMV antibody screening methods. Changes in blood banking procedures necessary to provide CMV-seronegative components are detailed. Providing CMV-seronegative components was a considerable undertaking; a mean, per patient, of 19 units of red cells and 105 units of platelets was required. Twenty percent of the platelet support was provided by family members and 80 percent by volunteer donors. CMV-infection was eliminated in all but one patient not considered infected at the time of transplantation. The capability to provide CMV-seronegative components depends on an adequate supply of seronegative donors, a sensitive and practical screening method for CMV antibody, a major commitment by the blood bank, and close communication between the blood bank and the patients' physicians. 相似文献
88.
Erosions of the ossicular chain that occurred as a complication of noncholesteatomatous chronic otitis media were studied with computed tomography (CT) in 55 patients. The incus (particularly the long and lenticular processes) was the ossicle most commonly involved (50 cases). Coronal and axial CT sections were complementary in the diagnosis of these erosions. Fibrous replacement of the incudostapedial articulation was diagnosed in four cases on axial CT scans when an unusually wide joint was present. 相似文献
89.
90.
Milton J. Guiberteau MD Pamela A. Wilcox RN MBA Sandra Bjork RN JD 《Journal of the American College of Radiology》2004,1(2):92-97
Clinical practice guidelines have emerged as a reality for medical practitioners over the past 20 years. Although virtually all groups interested in the development of practice guidelines hope for improvements in patient care, secondary expectations vary widely among those using them. Their use in daily practice by physicians has met with resistance from barriers including concerns of “cookbook” medicine, a loss of autonomy, and increased professional liability. The recent experience of the ACR in addressing these challenges illustrates that physicians are receptive to steps perceived to mitigate the risks accompanying the use of guidelines as well as to efforts to increase their understanding of implementing guidelines in clinical practice. The experiences of other medical societies and an inventory of future trends reveal additional challenges associated with the use of practice guidelines, as third parties look to guidelines as points of reference for gauging the performance of health care providers. 相似文献