全文获取类型
收费全文 | 792篇 |
免费 | 60篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 14篇 |
妇产科学 | 9篇 |
基础医学 | 126篇 |
口腔科学 | 3篇 |
临床医学 | 78篇 |
内科学 | 195篇 |
皮肤病学 | 7篇 |
神经病学 | 95篇 |
特种医学 | 21篇 |
外科学 | 88篇 |
综合类 | 3篇 |
预防医学 | 44篇 |
眼科学 | 8篇 |
药学 | 100篇 |
中国医学 | 6篇 |
肿瘤学 | 56篇 |
出版年
2023年 | 4篇 |
2022年 | 6篇 |
2021年 | 8篇 |
2020年 | 12篇 |
2019年 | 17篇 |
2018年 | 11篇 |
2017年 | 10篇 |
2016年 | 21篇 |
2015年 | 23篇 |
2014年 | 35篇 |
2013年 | 28篇 |
2012年 | 59篇 |
2011年 | 62篇 |
2010年 | 37篇 |
2009年 | 36篇 |
2008年 | 44篇 |
2007年 | 61篇 |
2006年 | 67篇 |
2005年 | 55篇 |
2004年 | 40篇 |
2003年 | 31篇 |
2002年 | 32篇 |
2001年 | 13篇 |
2000年 | 14篇 |
1999年 | 12篇 |
1998年 | 5篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 8篇 |
1993年 | 6篇 |
1992年 | 12篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1976年 | 2篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1972年 | 2篇 |
1970年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有858条查询结果,搜索用时 15 毫秒
31.
G. Feljandro P. Ramos Antoinette D. I. van Asselt Sandra Kuiper Johan L. Severens Tanja Maas Edward Dompeling J. André Knottnerus Onno C. P. van Schayck 《The European journal of health economics》2014,15(8):869-883
Background
Many children stand to benefit from being asthma-free for life with primary (i.e., prenatally started) prevention addressing one environmental exposure in a unifaceted (UF) approach or at least two in a multifaceted (MF) approach. We assessed the cost-effectiveness of primary prevention programmes for Dutch children in a decision-analytic framework.Methods
A decision-analytic tree model analysing healthcare costs and asthma cases prevented was developed to compare usual care (UC) with two UF and three MF programmes on the primary prevention of asthma amongst children. Programmes were evaluated through incremental cost-effectiveness ratios and net monetary benefits. Decision and parameter uncertainty were subjected to value-of-information analyses.Results
The current UC and one of three MF programmes dominated the other alternatives. The MF programme was more costly but also more effective than UC at an incremental cost-effectiveness ratio of €8,209.20/additional asthma case prevented. The value of perfect information to reduce uncertainty was €291.6M at its lowest. Most of the uncertainty in the cost-effectiveness threshold was attributable to the probability and cost estimates for low-risk children.Conclusion
This study supports the feasibility of a structured programme that simultaneously addresses exposure to house dust mites, pet dander, environmental tobacco, and breast-feeding as a cost-effective alternative to UC in the primary prevention of asthma amongst children. 相似文献32.
33.
34.
Lefetamine‐derived designer drugs N‐ethyl‐1,2‐diphenylethylamine (NEDPA) and N‐iso‐propyl‐1,2‐diphenylethylamine (NPDPA): Metabolism and detectability in rat urine using GC‐MS,LC‐MSn and LC‐HR‐MS/MS
下载免费PDF全文
![点击此处可从《Drug testing and analysis》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Carina S. D. Wink Golo M. J. Meyer Dirk K. Wissenbach Andrea Jacobsen‐Bauer Markus R. Meyer Hans H. Maurer 《Drug testing and analysis》2014,6(10):1038-1048
N‐Ethyl‐1,2‐diphenylethylamine (NEDPA) and N‐iso‐propyl‐1,2‐diphenylethylamine (NPDPA) are two designer drugs, which were confiscated in Germany in 2008. Lefetamine (N,N‐dimethyl‐1,2‐diphenylethylamine, also named L‐SPA), the pharmaceutical lead of these designer drugs, is a controlled substance in many countries. The aim of the present work was to study the phase I and phase II metabolism of these drugs in rats and to check for their detectability in urine using the authors’ standard urine screening approaches (SUSA). For the elucidation of the metabolism, rat urine samples were worked up with and without enzymatic cleavage, separated and analyzed by gas chromatography‐mass spectrometry (GC‐MS) and liquid chromatography‐high resolution‐tandem mass spectrometry (LC‐HR‐MS/MS). According to the identified metabolites, the following metabolic pathways for NEDPA and NPDPA could be proposed: N‐dealkylation, mono‐ and bis‐hydroxylation of the benzyl ring followed by methylation of one of the two hydroxy groups, combinations of these steps, hydroxylation of the phenyl ring after N‐dealkylation, glucuronidation and sulfation of all hydroxylated metabolites. Application of a 0.3 mg/kg BW dose of NEDPA or NPDPA, corresponding to a common lefetamine single dose, could be monitored in rat urine using the authors’ GC‐MS and LC‐MSn SUSA. However, only the metabolites could be detected, namely N‐deethyl‐NEDPA, N‐deethyl‐hydroxy‐NEDPA, hydroxy‐NEDPA, and hydroxy‐methoxy‐NEDPA or N‐de‐iso‐propyl‐NPDPA, N‐de‐iso‐propyl‐hydroxy‐NPDPA, and hydroxy‐NPDPA. Assuming similar kinetics, an intake of these drugs should also be detectable in human urine. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
35.
Chao Ding Brendon P Scicluna Ingrid Stroo Jack Yang Joris JTH Roelofs Onno J de Boer Alex F de Vos Peter Nürnberg Alexey S Revenko Jeff Crosby Cornelis van't Veer Tom van der Poll 《The Journal of pathology》2020,250(1):95-106
Prekallikrein (PKK, also known as Fletcher factor and encoded by the gene KLKB1 in humans) is a component of the contact system. Activation of the contact system has been implicated in lethality in fulminant sepsis models. Pneumonia is the most frequent cause of sepsis. We sought to determine the role of PKK in host defense during pneumosepsis. To this end, mice were infected with the common human pathogen Klebsiella pneumoniae via the airways, causing an initially localized infection of the lungs with subsequent bacterial dissemination and sepsis. Mice were treated with a selective PKK-directed antisense oligonucleotide (ASO) or a scrambled control ASO for 3 weeks prior to infection. Host response readouts were determined at 12 or 36 h post-infection, including genome-wide messenger RNA profiling of lungs, or mice were followed for survival. PKK ASO treatment inhibited constitutive hepatic Klkb1 mRNA expression by >80% and almost completely abolished plasma PKK activity. Klkb1 mRNA could not be detected in lungs. Pneumonia was associated with a progressive decline in PKK expression in mice treated with control ASO. PKK ASO administration was associated with a delayed mortality, reduced bacterial burdens, and diminished distant organ injury. While PKK depletion did not influence lung pathology or neutrophil recruitment, it was associated with an upregulation of multiple innate immune signaling pathways in the lungs already prior to infection. Activation of the contact system could not be detected, either during infection in vivo or at the surface of Klebsiella in vitro. These data suggest that circulating PKK confines pro-inflammatory signaling in the lung by a mechanism that does not involve contact system activation, which in the case of respiratory tract infection may impede early protective innate immunity. © 2019 Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
36.
Jessica L. de Beer Onno W. Akkerman Anita C. Schürch Arnout Mulder Tjip S. van der Werf Adri G. M. van der Zanden Jakko van Ingen Dick van Soolingen 《Journal of clinical microbiology》2014,52(5):1338-1342
Variable-number tandem-repeat (VNTR) typing with a panel of 24 loci is the current gold standard in the molecular typing of Mycobacterium tuberculosis complex isolates. However, because of technical problems, a part of the loci often cannot be amplified by multiplex PCRs. Therefore, a considerable number of single-locus PCRs have to be performed for the loci with missing results, which impairs the laboratory work flow. Therefore, the original in-house method described by Supply et al. in 2006 was reevaluated. We modified seven primers and the PCR master mixture and obtained a strongly optimized in-house 24-locus VNTR typing method. The percentage of instantly complete 24-locus VNTR patterns detected in the routine flow of typing activities increased to 84.7% from the 72.3% obtained with the typing conducted with the commercially available Genoscreen MIRU-VNTR typing kit. The analytical sensitivity of the optimized in-house method was assessed by serial dilutions of M. tuberculosis in bronchoalveolar lavage fluid. A 1:10 dilution of the different strains tested was the lowest dilution for the detection of a complete 24-locus VNTR pattern. The optimized in-house 24-locus VNTR typing method will reduce the turnaround time of typing significantly and also the financial burden of these activities. 相似文献
37.
38.
39.