全文获取类型
收费全文 | 1835篇 |
免费 | 130篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 148篇 |
妇产科学 | 21篇 |
基础医学 | 177篇 |
口腔科学 | 69篇 |
临床医学 | 206篇 |
内科学 | 423篇 |
皮肤病学 | 51篇 |
神经病学 | 47篇 |
特种医学 | 340篇 |
外科学 | 140篇 |
综合类 | 25篇 |
预防医学 | 78篇 |
眼科学 | 24篇 |
药学 | 106篇 |
1篇 | |
中国医学 | 1篇 |
肿瘤学 | 131篇 |
出版年
2023年 | 7篇 |
2022年 | 6篇 |
2021年 | 20篇 |
2020年 | 12篇 |
2019年 | 15篇 |
2018年 | 28篇 |
2017年 | 18篇 |
2016年 | 30篇 |
2015年 | 34篇 |
2014年 | 33篇 |
2013年 | 57篇 |
2012年 | 30篇 |
2011年 | 28篇 |
2010年 | 57篇 |
2009年 | 86篇 |
2008年 | 31篇 |
2007年 | 47篇 |
2006年 | 64篇 |
2005年 | 41篇 |
2004年 | 31篇 |
2003年 | 42篇 |
2002年 | 40篇 |
2001年 | 34篇 |
2000年 | 28篇 |
1999年 | 37篇 |
1998年 | 112篇 |
1997年 | 120篇 |
1996年 | 122篇 |
1995年 | 80篇 |
1994年 | 87篇 |
1993年 | 101篇 |
1992年 | 28篇 |
1991年 | 29篇 |
1990年 | 27篇 |
1989年 | 54篇 |
1988年 | 48篇 |
1987年 | 31篇 |
1986年 | 42篇 |
1985年 | 38篇 |
1984年 | 23篇 |
1983年 | 19篇 |
1982年 | 22篇 |
1981年 | 37篇 |
1980年 | 20篇 |
1979年 | 15篇 |
1978年 | 8篇 |
1977年 | 24篇 |
1976年 | 20篇 |
1975年 | 7篇 |
1974年 | 4篇 |
排序方式: 共有1990条查询结果,搜索用时 0 毫秒
31.
Guus MJ Bökkerink Maja Joosten Erik Leijte Maud YA Lindeboom Ivo de Blaauw Sanne MBI Botden 《Journal of pediatric surgery》2021,56(3):465-470
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II. 相似文献
32.
33.
34.
Pharmacokinetics of mitomycin C in patients receiving the drug alone or in combination 总被引:2,自引:0,他引:2
G A van Hazel M Scott J Rubin C G Moertel R T Eagan M J O'Connell J S Kovach 《Cancer treatment reports》1983,67(9):805-810
We have characterized plasma pharmacokinetics in 30 patients receiving mitomycin C (mitomycin) in doses ranging from 6 to 20 mg/m2 by iv bolus injection, either alone or in combination with other chemotherapeutic drugs. Plasma elimination of the drug was described by a two-compartment model in all but three cases, giving mean values for alpha-half-life of 8.2 mins, beta-half-life of 51.8 mins, and total body clearance of 332.9 ml/min/m2. The mean urinary excretion was 8.1% of the total dose administered. We did not detect alterations in pharmacologic parameters related to liver dysfunction, dose of mitomycin, and concomitant administration of other cytotoxic drugs. 相似文献
35.
36.
37.
Background
The ethnic usage of exotics and indigenous problem plants is a highly debated topic, as legislative requirements over-shadow their potential medicinal value, particularly to treat sexually transmitted infections (STIs). Limited information exists regarding their medicinal value among the Bapedi.Objectives
To ascertain the importance of exotics and indigenous problem plants in the treatment of STIs, a major global primary health care challenge.Methods
A field observation and semi-structured questionnaire focussing on species diversity, types of STIs treated and medicinal preparation as well as application was used to collect data from 34 traditional healers.Results
Seven exotics and three indigenous problem species were identified. These species were used to treat four STIs; with Catharanthus roseus illustrating its dominance in the treatment of gonorrhoea. Some medicinal species used by Bapedi traditional healers have been validated through scientific research or through their extensive use by various cultures in South Africa and other parts of Africa. To the best of our knowledge Alternanthera pungens, Caesalpinia decapetala, Cinnamomum verum, and Citrullus lanatus are reported for the first time in the treatment of the investigated STIs.Conclusions
Exotic and indigenous problem species constitute an important component of the STIs treatment protocol. Their utilization by Bapedi cautions against the narrow-minded approach of indiscriminate eradication, as these species can play a significant role in the primary health care needs of socio-economic vulnerable people. 相似文献38.
PAG Torrie A Leonidou IJ Harding G Wynne Jones MJ Hutchinson IW Nelson 《Annals of the Royal College of Surgeons of England》2013,95(8):604-608
Introduction
The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.Methods
Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.Results
The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).Conclusions
In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy. 相似文献39.
MJ Bown 《Annals of the Royal College of Surgeons of England》2014,96(6):405-414
Introduction
An individual’s genetic background plays a significant role in his or her chances of developing an abdominal aortic aneurysm (AAA). This risk is likely to be due to a combination of multiple small effect genetic factors acting together, resulting in considerable difficulty in the identification of these factors.Methods
Methods for the identification of genetic factors associated with disease are usually based on the analysis of genetic variants in case-control studies. Over the last decade, owing to advances in bioinformatics and laboratory technology, these studies have progressed from focusing on the examination of a single genetic variant in each study to the examination of many millions of variants in a single experiment. We have conducted a series of such experiments using these methods.Results
Our original methods using candidate gene approaches led to the initial identification of a genetic variant in the interleukin-10 gene associated with AAA. However, further studies failed to confirm this association and highlighted the necessity for adequately powered studies to be conducted, as well as the need for confirmatory studies to be performed, prior to the acceptance of a variant as a risk for disease. The subsequent application of genomic techniques to our sample set, in a global collaboration, has led to the identification of three robustly verified risk loci for AAA in the LRP1, LDLR and SORT1 genes.Conclusions
Genomic studies of AAA have led to the identification of new pathways involved in the pathogenesis of AAA. The exploration of these pathways has the potential to unlock new avenues for therapeutic intervention to prevent the development and progression of AAA. 相似文献40.
Neuropeptide Y Attenuates Stress‐Induced Bone Loss Through Suppression of Noradrenaline Circuits 下载免费PDF全文
PA Baldock S Lin L Zhang T Karl Y Shi F Driessler A Zengin B Hörmer NJ Lee IPL Wong EJD Lin RF Enriquez B Stehrer MJ During E Yulyaningsih S Zolotukhin ST Ruohonen E Savontaus A Sainsbury H Herzog 《Journal of bone and mineral research》2014,29(10):2238-2249
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research. 相似文献