全文获取类型
收费全文 | 139763篇 |
免费 | 12882篇 |
国内免费 | 8746篇 |
专业分类
耳鼻咽喉 | 1248篇 |
儿科学 | 1445篇 |
妇产科学 | 2044篇 |
基础医学 | 18469篇 |
口腔科学 | 2949篇 |
临床医学 | 17143篇 |
内科学 | 22800篇 |
皮肤病学 | 1680篇 |
神经病学 | 8905篇 |
特种医学 | 4794篇 |
外国民族医学 | 62篇 |
外科学 | 15364篇 |
综合类 | 19036篇 |
现状与发展 | 23篇 |
一般理论 | 18篇 |
预防医学 | 8653篇 |
眼科学 | 4292篇 |
药学 | 13739篇 |
102篇 | |
中国医学 | 6530篇 |
肿瘤学 | 12095篇 |
出版年
2024年 | 322篇 |
2023年 | 1697篇 |
2022年 | 4582篇 |
2021年 | 5709篇 |
2020年 | 4249篇 |
2019年 | 3806篇 |
2018年 | 4472篇 |
2017年 | 3680篇 |
2016年 | 3618篇 |
2015年 | 5184篇 |
2014年 | 6476篇 |
2013年 | 5949篇 |
2012年 | 8582篇 |
2011年 | 9573篇 |
2010年 | 5755篇 |
2009年 | 4759篇 |
2008年 | 6316篇 |
2007年 | 6307篇 |
2006年 | 6368篇 |
2005年 | 6082篇 |
2004年 | 4065篇 |
2003年 | 3962篇 |
2002年 | 3454篇 |
2001年 | 6393篇 |
2000年 | 6463篇 |
1999年 | 5928篇 |
1998年 | 2742篇 |
1997年 | 2324篇 |
1996年 | 1692篇 |
1995年 | 1508篇 |
1994年 | 1286篇 |
1993年 | 933篇 |
1992年 | 2483篇 |
1991年 | 2150篇 |
1990年 | 1945篇 |
1989年 | 1852篇 |
1988年 | 1598篇 |
1987年 | 1437篇 |
1986年 | 1248篇 |
1985年 | 1052篇 |
1984年 | 657篇 |
1983年 | 504篇 |
1982年 | 280篇 |
1981年 | 209篇 |
1980年 | 157篇 |
1979年 | 295篇 |
1978年 | 77篇 |
1974年 | 75篇 |
1973年 | 95篇 |
1972年 | 71篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
J Phua E S C Koay D Zhang L K Tai X L Boo K C Lim T K Lim 《The European respiratory journal》2006,28(4):695-702
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections. 相似文献
2.
3.
Vincent Chung Liang Liu Zhaoxiang Bian Zhongzhen Zhao Wai Leuk Fong Wan Fung Kum Jing Gao Min Li 《Movement disorders》2006,21(10):1709-1715
The objective of this study is to assess the efficacy and safety of herbal medicines (HMs), as a monotherapy or adjunct therapy, compared to placebo or conventional approaches in the treatment of idiopathic Parkinson's disease (PD). We conducted a systematic review of randomized controlled trials from both conventional and alternative medicine sources. Outcome measures were overall improvement, quality of life, reduction of levodopa dose, and adverse events. Nine studies were included, each testing a different HM. Six of the trials had limited internal validity due to major flaws in design, including the lack of proper randomization; insufficient blinding; unclear inclusive criteria in terms of diagnostic criteria, baseline staging, and duration of disease; lack of proper sample size calculation; and insufficient data analysis. Imbalances in gender and ethnicity among the patients in the included trials were observed. No major adverse events emerged, and no specific pattern was detected from the trials describing such data. In addition to major methodological defects, heterogeneity in (1) HM tested, (2) control treatment, and (3) outcome measure hindered in-depth data analysis and synthesis. Current evidence is insufficient to evaluate the efficacy and safety of various HMs. Further studies with improved trial design and reporting, with assessment on cost-effectiveness, quality of life, and qualitative data are warranted. 相似文献
4.
目的:为更清晰地显示顽固性气胸的漏气部位和性质,为不能耐受手术者摸索一种新的治疗手段。方法:选择18例患者,先用76%泛影葡胺行胸膜腔造影,而后在局部注入少量粘连剂。结果:造影后发现多发性肺大泡8例,单发性肺大泡6例,肺大泡伴粘连带4例。病变分别位于左上肺,右上肺,中下肺野及叶间裂。注射粘连剂后,15例一次成功,3例第二次成功。随防6~18个月,未见复发。结论:该方法易掌握,无明显副作用。病变显示明显,易被患者接受,具有明显的临床效果和推广价值 相似文献
5.
A. HAZIOT I. KATZ G. W. RONG X. Y. LIN J. SILVER & S. M. GOYERT 《Scandinavian journal of immunology》1997,46(3):242-245
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule. 相似文献
6.
V. S. Akhunov T. V. Mirenburg X. D. Krasnopolskaya 《Journal of inherited metabolic disease》1994,17(1):104-111
Summary GM1- and GM2-gangliosides were isolated from brain and radio-labelled. The labelled moieties were localized by hydrolysis with lysosomal enzymes, followed by thin-layer chromatography of the products. High-resolution loading tests with labelled gangliosides were developed and found to differentiate infantile and juvenile forms of GM1- and GM2-gangliosidoses as well as the identification of B, O and AB types of GM2-gangliosidosis. 相似文献
7.
It is well established that painful distension of hollow viscera such as the oesophagus can evoke a reflex tachycardia and pressor response; however, the nature of the oesophageal afferent pathway(s) remains controversial. This study investigated the afferent arc which mediates these reflex cardiovascular changes in the decerebrate rat. In addition, the effect of oesophageal distension on the respiratory activity of the costal diaphragm was studied. Focal distension of the oesophagus (volume of 0.3 ml applied for 10 s) just above the diaphragmatic hiatus evoked a reproducible pressor response and tachycardia in the decerebrate rat. Respiration was transiently inhibited at the beginning of oesophageal distension and prior to the rise in blood pressure. Neuromuscular blockade with the nicotinic acetylcholine receptor blocker alpha-bungarotoxin (140 microg bolus) had no effect on the magnitude of the cardiovascular response. Therefore the efferent supply to the striated muscle of the rat oesophagus was not essential in mediating this reflex. Signal averaging of the mean blood pressure response showed that neither selective ablation of oesophageal spinal afferents nor bilateral vagotomy altered the early trajectory of the pressure response. Bilateral vagotomy reduced the peak magnitude of the response to sustained oesophageal distension. In contrast, selective removal of spinal afferents had no effect on the response. Ablation of both neural pathways was essential to abolish the reflex cardiovascular and respiratory responses. It can be concluded that both vagal and spinal afferent pathways are utilised in the reflex cardiorespiratory response to painful oesophageal distension. Although ablation of one neural pathway had no effect on the response it was still implicated in the reflex, since ablation of both pathways was necessary to prevent the cardiorespiratory changes. This study emphasises the need for caution when inferences are made concerning single selective ablations of multiply innervated organs. 相似文献
8.
Measurements of the fetal eyeball and its pattern of growth 总被引:1,自引:0,他引:1
9.
10.
Evaluation of adhesive strength of five dental adhesive cements and two visible light-activated composite resins 总被引:2,自引:0,他引:2
C X Zhang 《中华口腔医学杂志》1987,22(5):298-300