全文获取类型
收费全文 | 1630篇 |
免费 | 109篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 75篇 |
妇产科学 | 16篇 |
基础医学 | 174篇 |
口腔科学 | 20篇 |
临床医学 | 294篇 |
内科学 | 330篇 |
皮肤病学 | 8篇 |
神经病学 | 146篇 |
特种医学 | 282篇 |
外国民族医学 | 1篇 |
外科学 | 166篇 |
综合类 | 32篇 |
一般理论 | 1篇 |
预防医学 | 59篇 |
眼科学 | 44篇 |
药学 | 48篇 |
中国医学 | 2篇 |
肿瘤学 | 55篇 |
出版年
2019年 | 15篇 |
2018年 | 23篇 |
2017年 | 12篇 |
2016年 | 14篇 |
2015年 | 30篇 |
2014年 | 16篇 |
2013年 | 74篇 |
2012年 | 38篇 |
2011年 | 52篇 |
2010年 | 37篇 |
2009年 | 33篇 |
2008年 | 45篇 |
2007年 | 62篇 |
2006年 | 53篇 |
2005年 | 56篇 |
2004年 | 34篇 |
2003年 | 29篇 |
2002年 | 42篇 |
2001年 | 28篇 |
2000年 | 26篇 |
1999年 | 40篇 |
1998年 | 45篇 |
1997年 | 38篇 |
1996年 | 42篇 |
1995年 | 36篇 |
1994年 | 54篇 |
1993年 | 39篇 |
1992年 | 49篇 |
1991年 | 39篇 |
1990年 | 32篇 |
1989年 | 65篇 |
1988年 | 76篇 |
1987年 | 71篇 |
1986年 | 43篇 |
1985年 | 46篇 |
1984年 | 36篇 |
1983年 | 35篇 |
1982年 | 11篇 |
1981年 | 27篇 |
1980年 | 18篇 |
1979年 | 20篇 |
1978年 | 17篇 |
1977年 | 14篇 |
1976年 | 21篇 |
1975年 | 22篇 |
1974年 | 20篇 |
1972年 | 16篇 |
1971年 | 14篇 |
1970年 | 12篇 |
1969年 | 11篇 |
排序方式: 共有1785条查询结果,搜索用时 15 毫秒
101.
102.
This paper summarizes the results of systematic studies published in peer-reviewed journals from 1999 to 2002 addressing post-traumatic
stress reactions in children after mass disasters. Children’s post-traumatic reactions are considered in five different contexts—natural
disasters, large-scale human-induced accidents, spree shootings, war, and terrorism. Association of these reactions with gender
and age, as well as longitudinal course, is addressed. Other post-traumatic reactions in children after a mass disaster, as
well as the comorbidity of these with stress reactions, are reported. With this as background, the most relevant epidemiologic
investigations conducted after the World Trade Center attacks are then described. It is expected that new knowledge in the
area of children’s post-traumatic reactions to disasters will result from the research initiatives launched after September
11, 2001. 相似文献
103.
Uptake, transport, and delivery of antimicrobial agents by human polymorphonuclear neutrophils 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Antimicrobial agents and chemotherapy》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Polymorphonuclear neutrophils (PMN) are attracted to sites of infection. They have the potential to deliver antimicrobial agents to these sites if the agents enter the cells and do not alter migration. Penicillin G did not enter cells and was not transported by PMN. We found that azithromycin, ciprofloxacin, levofloxacin, moxifloxacin, and telithromycin were concentrated in PMN and transported toward a chemoattractant. These antimicrobial agents were released from the PMN and inhibited the growth of bacteria on test plates. 相似文献
104.
105.
106.
Diagnostic accuracy of fine-needle aspiration and frozen section in nodular thyroid disease. 总被引:2,自引:0,他引:2
D L Mandell E M Genden J I Mechanick D A Bergman H F Biller M L Urken 《Otolaryngology--head and neck surgery》2001,124(5):531-536
OBJECTIVE: To assess the diagnostic accuracy of fine-needle aspiration (FNA) and frozen section (FS) in nodular thyroid disease. SETTING: Tertiary care academic medical center. STUDY DESIGN: Retrospective review of 139 consecutive patients undergoing surgery for nodular thyroid disease. FNA and FS sensitivity, specificity, and accuracy were calculated with respect to permanent section histology. RESULTS: Among 63 patients with an FNA interpreted as either benign (n = 38) or malignant (n = 25), FNA was accurate (sensitivity 89%, specificity 97%, accuracy 94%). FS identified only one case of carcinoma missed by FNA. Among 76 patients with a "suspicious" FNA, FS was reasonably accurate (sensitivity 67%, specificity 100%, accuracy 89%), but was deferred in 50% of cases. CONCLUSION: Given high FNA accuracy, more selective use of FS is suggested. SIGNIFICANCE: The study results will assist with intra-institutional patient counseling and intraoperative decision-making with respect to FNA and FS results in patients with nodular thyroid disease. 相似文献
107.
Mechanical trauma induces rapid astroglial activation of ERK/MAP kinase: Evidence for a paracrine signal 总被引:6,自引:0,他引:6
Astrogliosis is a prominent and ubiquitous reaction of astrocytes to many forms of CNS injury, often implicated in the poor regenerative capacity of the adult mammalian CNS. Transmembrane signals that rapidly trigger and maintain astroglial responses to injury are largely undefined. Several candidate inducers of astrogliosis, including growth factors and neuropeptides, act via the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway. We previously observed chronically activated ERK/MAPK in human reactive astrocytes. To investigate mechanisms of pathway activation in a defined in vitro model, primary cultured astroglial monolayers were subjected to focal mechanical injury. Within 2-10 min, ERK/MAPK was activated, but only in cells near the wound edge. By 30 min, the entire monolayer showed activation, which persisted for 4 to 8 h. ERK/MAPK activation was specifically blocked by application of the MEK inhibitors, PD98059 and U0126. Cell-cell contact was not necessary for intercellular spread of ERK/MAPK activation, and ERK/MAPK-stimulating activity was found in the injury-conditioned medium. The activating factor was shown to have a native size of 50-100 kD and did not signal through the classical EGF receptor. Injury-induced signaling to ERK/MAPK required Ras, as demonstrated by specific blockade after transient transfection with a dominant negative Ha-RasN17 construct. Finally, we demonstrated that focal lesioning of adult rat cortex induces a rapid activation and spreading of astroglial ERK/MAPK, suggesting that similar mechanisms may operate in astroglial activation following acute brain injury. 相似文献
108.
Mandell DL Genden EM Biller HF Urken ML 《Archives of otolaryngology--head & neck surgery》2000,126(3):303-307
OBJECTIVE: To report our experience in a case series of 5 posterior scalping flaps. DESIGN: Retrospective review of a case series. SETTING: A tertiary academic care otolaryngology-head and neck surgery referral center. PATIENTS: Five patients having undergone posterior scalping flap reconstruction of cutaneous midface defects. METHODS: Reconstruction was performed for 4 cheek defects, 1 of which included the lateral third of the upper and lower lips, and 1 combined midfacial and lateral nasal wall defect. RESULTS: All 5 patients had excellent cosmetic and functional results. The only complication was a single case of partial-thickness distal flap necrosis. CONCLUSION: The posterior scalping flap offers a reliable source of skin with appropriate color and texture and minimal donor-site morbidity. 相似文献
109.
Pneumococci can enter and survive inside human lung alveolar carcinoma cells. We examined the activity of azithromycin, gentamicin, levofloxacin, moxifloxacin, penicillin G, rifampin, telithromycin, and trovafloxacin against pneumococci inside and outside cells. We found that moxifloxacin, trovafloxacin, and telithromycin were the most active, but only telithromycin killed all intracellular organisms. 相似文献