全文获取类型
收费全文 | 20895篇 |
免费 | 444篇 |
国内免费 | 496篇 |
专业分类
耳鼻咽喉 | 598篇 |
儿科学 | 1261篇 |
妇产科学 | 389篇 |
基础医学 | 2085篇 |
口腔科学 | 713篇 |
临床医学 | 1098篇 |
内科学 | 4937篇 |
皮肤病学 | 372篇 |
神经病学 | 1532篇 |
特种医学 | 563篇 |
外科学 | 3598篇 |
综合类 | 195篇 |
一般理论 | 10篇 |
预防医学 | 2071篇 |
眼科学 | 492篇 |
药学 | 1232篇 |
中国医学 | 211篇 |
肿瘤学 | 478篇 |
出版年
2024年 | 3篇 |
2023年 | 20篇 |
2022年 | 53篇 |
2021年 | 81篇 |
2020年 | 79篇 |
2019年 | 100篇 |
2018年 | 127篇 |
2017年 | 54篇 |
2016年 | 127篇 |
2015年 | 75篇 |
2014年 | 113篇 |
2013年 | 52篇 |
2012年 | 1976篇 |
2011年 | 2239篇 |
2010年 | 508篇 |
2009年 | 263篇 |
2008年 | 1727篇 |
2007年 | 1976篇 |
2006年 | 1739篇 |
2005年 | 1876篇 |
2004年 | 1791篇 |
2003年 | 1714篇 |
2002年 | 1610篇 |
2001年 | 1078篇 |
2000年 | 1573篇 |
1999年 | 719篇 |
1998年 | 81篇 |
1997年 | 13篇 |
1996年 | 12篇 |
1995年 | 14篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1957年 | 1篇 |
1942年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Quiralte J Sánchez-García F Torres MJ Blanco C Castillo R Ortega N de Castro FR Pérez-Aciego P Carrillo T 《The Journal of allergy and clinical immunology》1999,103(4):685-689
BACKGROUND: Several HLA alleles have been associated with asthma induced by nonsteroidal anti-inflammatory drugs (NSAIDs). The existence of HLA markers linked to other NSAID-induced reactions, such as cutaneous and anaphylactoid reactions, has not been established. OBJECTIVE: The purpose of our work was to study the HLA-DRB1 and HLA-DQB1 alleles in patients with cutaneous and anaphylactoid reactions caused by NSAIDs. METHODS: We have analyzed 114 HLA DRB1 and 26 HLA-DQB1 alleles in 21 patients with anaphylactoid reactions caused by NSAIDs, 47 patients who had exclusively cutaneous reactions during single-blind, placebo-controlled oral challenges with NSAIDs, and 167 tolerant control subjects (29 of whom had also had an IgE-mediated anaphylaxis to different agents). HLA-DRB1 and HLA-DQB1 alleles were typed by the polymerase chain reaction sequence-specific primers method with genomic DNA. RESULTS: The frequency of HLA-DR11 alleles was 58.8% in the anaphylactoid reaction group, compared with 15.9% in the NSAID-tolerant healthy control subjects (OR, 7:3; 95% confidence interval, 2.8-19.0; P <.02) and 6.3% in the group of the patients with a tolerance for NSAIDs and with IgE-mediated anaphylaxis (OR, 18.75; 95% confidence interval, 4.3-81.1; P <.004). No differences were observed among HLA-DR11 alleles analyzed. There were no significant HLA-DQB1 associations with NSAID-induced anaphylactoid reactions. Patients with cutaneous reactions had HLA frequencies that did not differ significantly from the tolerant control subjects. CONCLUSION: The HLA-DRB1*11 alleles showed a positive association with NSAID-induced anaphylactoid reactions. 相似文献
32.
33.
Vendrell JM García F Veiga A Calderón G Egozcue S Egozcue J Barri PN 《Human reproduction (Oxford, England)》1999,14(2):375-378
The incidence of meiotic abnormalities and their relationship with different spermatogenic parameters was assessed in 103 male patients with presumably idiopathic severe oligoasthenozoospermia (motile sperm concentration < or = 1.5 x 10(6)/ml). Meiosis on testicular biopsies was independently evaluated by two observers. Meiotic patterns included normal meiosis and two meiotic abnormalities, i.e. severe arrest and synaptic anomalies. A normal pattern was found in 64 (62.1%), severe arrest in 21 (20.4%) and synaptic anomalies in 18 (17.5%). The overall rate of meiotic abnormalities was 37.9%. Most (66.7%) meiotic abnormalities occurred in patients with a sperm concentration < or = 1 x 10(6)/ml. In this group, total meiotic abnormalities were found in 57.8% of the patients; of these, 26.7% had synaptic anomalies. When the sperm concentration was < or = 0.5 x 10(6)/ml, synaptic anomalies were detected in 40% of the patients. In patients with increased follicle stimulating hormone (FSH) concentrations, total meiotic abnormalities occurred in 54.8% (synaptic anomalies in 22.6%). There were statistically significant differences among the three meiotic patterns in relation to sperm concentration (P < 0.001) and serum FSH concentration (P < 0.05). In the multivariate analysis, sperm concentration < or = 1 x 10(6)/ml and/or FSH concentration > 10 IU/l were the only predictors of meiotic abnormalities. 相似文献
34.
35.
García Vicente A García Del Castillo E Soriano Castrejón A Alonso Farto J 《Revista espanola de medicina nuclear》1999,18(5):367-370
Esthesioneuroblastoma is an uncommon tumor originating in the upper nasal cavity and constitutes 3% of all intranasal neoplasms. Few references exist about the expression of somatostatin receptors in these tumors. Our case demonstrates a good correlation between the somatostatin receptor scintigraphy and magnetic resonance imaging. 相似文献
36.
Fuster D Navasa M Pons F Vidal-Sicart S Mateos JJ Lomeña F Rodes J Herranz R 《Clinical nuclear medicine》1999,24(12):955-958
Major neuroendocrine tumors contain many somatostatin receptors. This feature allows for the localization of primary tumors and tumor metastases by scintigraphy with the radiolabeled somatostatin analog octreotide. We describe a patient with nonspecific clinical data and ultrasonography and CT that showed an isolated focal lesion in the liver. In-111 octreotide scintigraphy was essential in establishing the diagnosis of liver metastasis from a neuroendocrine tumor confirmed by pathologic findings. Because clinical symptoms recurred, ultrasonography and CT were performed a few months after surgery. Both were negative. However, In-111 octreotide scintigraphy suggested multiple bone metastases and established the diagnosis of bone metastases from a neuroendocrine tumor, which was confirmed by Tc-99m MDP bone scans and MRI. 相似文献
37.
Aleksic I Saldaña F Busch T Basenau D Sîrbu H Schauer A Dalichau H 《The Annals of thoracic surgery》1999,67(1):224-225
A 66-year-old woman was referred for coronary bypass operation to the left anterior descending and the circumflex arteries. She had a systemic inflammatory process of unknown origin. On opening the pericardium, fibrotic plaques encircling the entire ascending aorta were found. Aortic cannulation and proximal anastomosis of the planned vein graft were impossible. The right internal mammary was anastomosed to the left anterior descending artery, the left to the obtuse marginal after femoral arterial cannulation. Pathologic examination revealed idiopathic mediastinal fibrosis. 相似文献
38.
39.
40.