全文获取类型
收费全文 | 25239篇 |
免费 | 2837篇 |
国内免费 | 1412篇 |
专业分类
耳鼻咽喉 | 203篇 |
儿科学 | 326篇 |
妇产科学 | 219篇 |
基础医学 | 1920篇 |
口腔科学 | 415篇 |
临床医学 | 2946篇 |
内科学 | 2380篇 |
皮肤病学 | 256篇 |
神经病学 | 795篇 |
特种医学 | 1194篇 |
外国民族医学 | 1篇 |
外科学 | 2233篇 |
综合类 | 6926篇 |
现状与发展 | 5篇 |
一般理论 | 4篇 |
预防医学 | 2716篇 |
眼科学 | 338篇 |
药学 | 2884篇 |
44篇 | |
中国医学 | 2328篇 |
肿瘤学 | 1355篇 |
出版年
2024年 | 73篇 |
2023年 | 345篇 |
2022年 | 870篇 |
2021年 | 1132篇 |
2020年 | 1076篇 |
2019年 | 578篇 |
2018年 | 657篇 |
2017年 | 829篇 |
2016年 | 637篇 |
2015年 | 1068篇 |
2014年 | 1404篇 |
2013年 | 1565篇 |
2012年 | 2297篇 |
2011年 | 2378篇 |
2010年 | 1970篇 |
2009年 | 1716篇 |
2008年 | 1891篇 |
2007年 | 1907篇 |
2006年 | 1577篇 |
2005年 | 1309篇 |
2004年 | 973篇 |
2003年 | 819篇 |
2002年 | 698篇 |
2001年 | 558篇 |
2000年 | 408篇 |
1999年 | 200篇 |
1998年 | 81篇 |
1997年 | 74篇 |
1996年 | 79篇 |
1995年 | 57篇 |
1994年 | 45篇 |
1993年 | 22篇 |
1992年 | 48篇 |
1991年 | 26篇 |
1990年 | 15篇 |
1989年 | 17篇 |
1988年 | 25篇 |
1987年 | 15篇 |
1986年 | 21篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 12篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
991.
目的检测免疫接种卡介苗(BCG)后大鼠行为学,电生理,海马神经元树突棘的变化。为进一步研究疫苗接种对突触传递和学习记忆的影响提供依据。方法实验分为卡介组和对照组。新生Sprague-Dawley(SD)大鼠于出生24h内背部皮下接种卡介苗,对照组皮下注射等量的PBS。4周时水迷宫检测其行为学的变化,在体LTP测其电生理的变化,并使用基因枪散射DiI染料法检测海马神经元树突棘的变化。结果与其对照组相比,卡介组空间学习记忆能力明显增强:LTP结果显著优于对照组;海马神经元树突棘的密度以及蘑菇样(mushroom)增多。结论新生期成功接种疫苗可以提高大鼠突触传递的可塑性并促进其学习记忆能力。 相似文献
992.
目的:观察下颌骨功能性偏斜对发育期大鼠髁突软骨内I型、II型以及III型胶原纤维分布及表达的影响。方法:取4周龄雄性SD大鼠40只,随机分为实验组(20只)和正常对照组(20只)。实验组佩戴自制的上切牙金属牙套引导下颌骨功能性右偏,对照组不佩戴任何装置,分别于实验1周、4周取得标本。HE染色及番红-O染色观察髁突软骨组织形态,苦味酸-天狼猩红偏振光染色以及免疫组化染色分别观察髁突软骨内I型、II型、III型胶原纤维含量以及分布表达情况,并进行相关半定量图像分析。结果:HE以及番红-O染色显示,实验1周后实验组牵张侧较正常组髁突软骨厚度显著增加,到4周后两组差异不显著;而实验组受压侧髁突软骨厚度4周后显著下降。天狼猩红染色及免疫组化染色结果显示,I型胶原主要表达在增殖层至成骨细胞层,II型胶原主要表达在软骨细胞层和肥大层。与正常组相比,1周及4周时实验组牵张侧软骨中区I型及II型胶原表达增强;受压侧软骨后区I型及II型胶原表达均显著减少。III型胶原主要表达在软骨纤维层至软骨细胞层,两组间无显著表达差异。结论:下颌骨功能性偏斜导致两侧髁突软骨发生了差异性生长改建,I型及II型胶原参与了改建中软骨内骨化过程。 相似文献
993.
Inflammatory bowel disease (IBD) is characterized by periods of symptomatic remission and relapse. Diagnosis and assessment of IBD are based on clinical evaluation, serum parameters, radiology, and endoscopy. Fecal markers have emerged as new diagnostic tools to detect and monitor intestinal inflammation. Fecal calprotectin (FC) and lactoferrin (FL) were identified decades ago as potentially revolutionary markers for IBD. Following these discoveries numerous additional markers, including S100A12, M2-PK, metalloproteinases, hemoglobin, myeloperoxidase, lysozyme, polymorphonuclear elastase, neopterin, and nitric oxide, have also been suggested as novel markers of IBD. But only FC and FL are used for the management of clinical IBD patients. The objective of this review is to introduce the clinical applications of fecal markers in the diagnosis, monitoring and prediction of outcomes of inflammatory bowel disease. 相似文献
994.
995.
阿尔茨海默病(AD)是老年期痴呆的最常见类型。早期诊断AD对于延缓病情进展、改善患者预后十分重要。目前AD研究热点已前移到临床前期,即主观认知减退(SCD)阶段,故采用生物学标记预测SCD是否进展为AD十分必要。本文对SCD的影像学研究进展进行综述。 相似文献
996.
Open reduction and pre-contoured locking plate fixation is a popular treatment option for displaced midshaft clavicle fracture. Lag screw and cerclage are 2 main intraoperative techniques to reduce and fix fragments. However, both lag screw and metallic cerclage have disadvantages. The doubled-suture Nice knot has been reported in many areas of orthopedic surgery for its effectiveness. This study aims to compare the outcomes of comminuted mid-shaft clavicle fractures reduced by Nice knots vs traditional techniques (lag screw or/and metallic cerclage) when bridged with pre-contoured locking plates.We retrospectively reviewed 101 patients (65 females and 36 males) diagnosed with midshaft clavicle fractures with at least one wedge fragment reduced by either Nice knots or traditional methods and bridged with pre-contoured locking plates between December 2016 and April 2019. Operation time, functional outcomes, pain, patient satisfaction, fracture healing, and complications were assessed at a follow-up of 12 to 40 months.The mean age of all the patients was 50.8 years. There were 52 and 49 patients in the Nice knot group and traditional group respectively, and no differences between 2 groups were found in general patient characteristics, fracture type, follow up and injury-to-surgery duration. The Nice knot group had significant less operation time (P < .01) than the traditional group (mean and standard deviation [SD], 78.6 ± 19.0 compared with 94.4 ± 29.9 minutes, respectively). For healing time, functional score, pain, satisfaction and complications, there were no significant differences between groups, despite the Nice knot group had slightly better results.Both Nice knots and traditional methods treated for comminuted Robinson type 2B clavicle fractures were effective and safe. And the Nice knots seemed to be superior with significant less operation time. 相似文献
997.
998.
Rationale:Systemic lupus erythematosus (SLE) is an important cause of stroke, more than a half the cases present as acute ischemic stroke. Thrombolysis is an effective choice in most cases, but for large vessel occlusion, mechanical thrombectomy is more effective. Here we reported a case of SLE-related stroke with left middle cerebral artery (MCA) occlusion, who was successfully treated by MT and tirofiban.Patient concern:A 38-year-old female suffered from right hemiplegia and aphasia for 8 hours. She was diagnosed with SLE 20 years ago, and neuropsychiatric SLE was considered 8 months before this onset. One month ago, glucocorticoids were discontinued by herself because of deterioration of bilateral femoral head osteonecrosis.Diagnosis:Left MCA occlusion was confirmed by computed tomography perfusion.Intervention:Immediate mechanical thrombectomy was performed and tirofiban was given to prevent re-occlusion of left MCA. Twenty fourhours later oral antiplatelet was given after intracranial hemorrhage was ruled out.Outcomes:Her neurological symptom improved several days later, and she was transferred to further rehabilitation. At 4 months follow-up she can live independently with mild hypophrasia. There was no further events of ischemic stroke in 1-year follow-up.Lessons:Mechanical thrombectomy is a highly effective and indispensable treatment for SLE related large vessel occlusion. In addition, tirofiban may reduce vessel reocclusion in special cases such as SLE and artery stenosis. 相似文献
999.
Chen Yi Zhang Hongzhou Chen Yuxin Li Meng Luo Wei Liu Yue Fu Yang Xia Huasong Xu Cong Jiang Yu Wu Yanqing 《Clinical rheumatology》2022,41(6):1873-1887
Clinical Rheumatology - Colchicine is an ancient anti-inflammatory drug. In recent years, an increasing number of studies have shown that colchicine improves the prognosis of patients with coronary... 相似文献
1000.
目的 实现荧光定量PCR技术在鼠疫现场和基层的应用。方法 本试验将已建立的基于核酸预混室温储运技术的荧光定量PCR方法应用于我国各鼠疫疫源地野生菌株的检测,进行特异性评价。选取分布于我国境内不同鼠疫疫源地野生鼠疫耶尔森氏菌株、鼠疫减毒菌株、耶尔森菌属近缘菌株假结核菌及小肠结肠炎菌进行荧光定量PCR检测。结果 55株鼠疫耶尔森氏菌及鼠疫减毒菌株扩增阳性,假结核耶尔森氏菌、小肠结肠炎耶尔森氏菌无阳性扩增,冻干试剂在室温25 ℃和37 ℃条件下可保存6个月,敏感性与冷冻保存无差异,核酸扩增诊断可在1 h内完成。结论 应用基于核酸预混室温储运技术的荧光定量PCR方法对我国各鼠疫疫源地55株鼠疫耶尔森氏菌检测呈现高度特异性,本试验冻干试剂具有可室温保存、便于运输、检测结果精准、快速等特点,具有较好的鼠疫现场应用前景。 相似文献