全文获取类型
收费全文 | 92456篇 |
免费 | 9504篇 |
国内免费 | 6785篇 |
专业分类
耳鼻咽喉 | 704篇 |
儿科学 | 1081篇 |
妇产科学 | 935篇 |
基础医学 | 9748篇 |
口腔科学 | 1659篇 |
临床医学 | 12544篇 |
内科学 | 13309篇 |
皮肤病学 | 850篇 |
神经病学 | 4539篇 |
特种医学 | 3213篇 |
外国民族医学 | 59篇 |
外科学 | 8634篇 |
综合类 | 18011篇 |
现状与发展 | 40篇 |
一般理论 | 5篇 |
预防医学 | 7222篇 |
眼科学 | 2393篇 |
药学 | 10823篇 |
83篇 | |
中国医学 | 5865篇 |
肿瘤学 | 7028篇 |
出版年
2024年 | 392篇 |
2023年 | 1548篇 |
2022年 | 3709篇 |
2021年 | 4661篇 |
2020年 | 3624篇 |
2019年 | 3002篇 |
2018年 | 2996篇 |
2017年 | 3012篇 |
2016年 | 2729篇 |
2015年 | 4269篇 |
2014年 | 5344篇 |
2013年 | 4967篇 |
2012年 | 7621篇 |
2011年 | 7968篇 |
2010年 | 5203篇 |
2009年 | 4177篇 |
2008年 | 5312篇 |
2007年 | 5221篇 |
2006年 | 4962篇 |
2005年 | 4700篇 |
2004年 | 3170篇 |
2003年 | 3098篇 |
2002年 | 2508篇 |
2001年 | 2033篇 |
2000年 | 1963篇 |
1999年 | 1999篇 |
1998年 | 1198篇 |
1997年 | 1158篇 |
1996年 | 833篇 |
1995年 | 777篇 |
1994年 | 752篇 |
1993年 | 449篇 |
1992年 | 605篇 |
1991年 | 464篇 |
1990年 | 431篇 |
1989年 | 354篇 |
1988年 | 347篇 |
1987年 | 277篇 |
1986年 | 246篇 |
1985年 | 195篇 |
1984年 | 102篇 |
1983年 | 65篇 |
1982年 | 46篇 |
1981年 | 44篇 |
1980年 | 22篇 |
1979年 | 45篇 |
1978年 | 15篇 |
1977年 | 14篇 |
1964年 | 7篇 |
1936年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
后发障是儿童白内障最常见的并发症,是导致术后视力下降的主要原因,故降低后发障的发生率对提高术后视力及减少弱视的发生非常重要,以往文献报道大多是术后行ND-YAG激光后囊切开术来治疗后发障。笔者近年对儿童白内障采用白内障摘除人工晶体植入联合后囊连续环形撕囊术预防人工晶体术后后囊混浊,效果肯定,报告如下。 相似文献
12.
目的 探讨种植受体血管内皮细胞在抗异种血管移植超急排斥反应 (HAR)方面的意义。方法 选用豚鼠→大鼠移植模型 ,先将分离、培养的大鼠动脉内皮细胞种植于去内皮的豚鼠动脉内壁 ,再将此豚鼠动脉植入大鼠体内 ,观察动脉血栓形成时间 ,并采用免疫组化技术检测了 Ig M、C3在移植后豚鼠动脉壁上沉积的情况。结果 已种植大鼠内皮细胞的豚鼠动脉血栓形成时间 (2 0 .3± 4.42 h)较植入大鼠体内的正常豚鼠动脉 (0 .35± 0 .2 84h)以及单纯去内皮豚鼠动脉血栓形成时间 (0 .16 5± 0 .0 77h)显著延长 (P<0 .0 0 1)。免疫组化结果显示 ,植入大鼠体内的正常豚鼠内皮细胞表面有 Ig M和 C3沉积 ,而预先种植大鼠内皮细胞的豚鼠动脉内壁无 Ig M和 C3沉积。结论 在异种供体血管壁上预先种植受者血管内皮细胞 ,可延长移植的异种供体血管通畅时间 ,该技术可能在抗异种血管移植 HAR方面具有重要意义 相似文献
13.
心脾综合征的多普勒超声心动图诊断 总被引:1,自引:0,他引:1
目的:探讨多普勒超声心动图对心脾综合征的诊断价值,分析其心脏伴随畸形漏诊及误诊原因,提高对心脾综合征诊断的准确率。方法:本文总结了221例心脾综合征患儿的超声检测结果,并与其心血管造影或磁共振检查结果进行对照。结果:超声心动图诊断为心脾综合征与心导管或磁共振结论符合者199例(占90.0%),诊断不符合者22例(占10.0%)。结论:多普勒超声心动图可以较准确地诊断心脾综合征,但对其心脏伴随畸形检出的准确率尚待进一步提高。 相似文献
14.
Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
相似文献
15.
16.
Lesley B Milgrom Jo Ann Brooks Rong Qi Karen Bunnell Susie Wuestfeld Daniel Beckman 《American journal of critical care》2004,13(2):116-125
BACKGROUND: Acute pain is common after cardiac surgery and can keep patients from participating in activities that prevent postoperative complications. Accurate assessment and understanding of pain are vital for providing satisfactory pain control and optimizing recovery. OBJECTIVES: To describe pain levels for 5 activities expected of patients after cardiac surgery on postoperative days 1 to 6 and changes in pain levels after chest tube removal and extubation. METHODS: Adults who underwent cardiac surgery were asked to rate the pain associated with various types of activities on postoperative days 1 to 6. Pain levels were compared by postoperative day, activity, and type of cardiac surgery. Pain scores before and after chest tube removal and extubation also were analyzed. RESULTS: Pain scores were higher on earlier postoperative days. The order of overall pain scores among activities (P < .01) from highest to lowest was coughing, moving or turning in bed, getting up, deep breathing or using the incentive spirometer, and resting. Changes in pain reported with coughing (P = .03) and deep breathing or using the incentive spirometer (P = .005) differed significantly over time between surgery groups. After chest tubes were discontinued, patients had lower pain levels at rest (P = .01), with coughing (P = .05), and when getting up (P = .03). CONCLUSIONS: Pain relief is an important outcome of care. A comprehensive, individualized assessment of pain that incorporates activity levels is necessary to promote satisfactory management of pain. 相似文献
17.
X Dong M He X Song B Lu Y Yang S Zhang N Zhao L Zhou Y Li X Zhu R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks. 相似文献
18.
以曼氏血吸虫的虫卵和成虫免疫家兔后所产生的特异性抗体,可用以日本血吸虫虫卵、尾蚴和成虫为抗原分别进行的COP,CHR和ELACIEP测出,表明两种人体血吸虫存有显著的交叉抗原成分。应用此种血清交叉反应性,以检测抗异种人体血吸虫的抗体,似有效而可取的,可用以辅助诊断援外回国人员是否感染国外人体血吸虫病。 相似文献
19.
Bent H. Hellum Zhuohan Hu Odd Georg Nilsen 《Basic & clinical pharmacology & toxicology》2009,105(1):58-63
Abstract: The aim of this study was to evaluate in vitro the dose‐dependent induction potential of six commonly used trade herbal products on CYP2C19 and CYP2E1 metabolic activities in cultured human hepatocytes. S‐mephenytoin and chlorzoxazone were used as specific CYP substrates, respectively, and rifampicin was used as a positive induction control for both enzymes. The hepatocytes were exposed to herbal extracts in increasing and biological relevant concentrations for 72 hrs and CYP substrate metabolites were quantified by validated HPLC methodologies. The major findings were that St John's wort was the most potent CYP‐modulating herb, showing a dose‐dependent induction/inhibition of both CYP2C19 and CYP2E1, with induction at low dosages and inhibition at higher. Ginkgo biloba showed an induction/inhibition profile towards CYP2C19 which was similar but weaker than that observed for St John's wort. If cooperative mechanisms are involved is still an open question. Common sage induced CYP2C19 in a log‐linear dose‐dependent manner with increasing concentrations. Common valerian was a weak inducer of CYP2C19, while horse chestnut and cone flower were characterized as non‐inducers of CYP2C19. Only St John's wort showed an inductive effect towards CYP2E1. In addition to St John's wort, Gingko biloba and common sage should be considered as possible candidates for clinically relevant drug‐herb interactions with selected CYP2C19 substrates. 相似文献
20.
目的:观察五白散胶囊治疗慢性消化道出血的疗效.方法:治疗组15例用五白散胶囊治疗,对照组15例用维霉素、果胶铋、止血敏治疗.结果:治疗组总有效率100%,对照组总有效率86.6%,两组比较有显著性差异(P<0.05).结论:五白散胶囊治疗消化道溃疡出血止血功效良好. 相似文献