全文获取类型
收费全文 | 13816篇 |
免费 | 906篇 |
国内免费 | 434篇 |
专业分类
耳鼻咽喉 | 178篇 |
儿科学 | 443篇 |
妇产科学 | 198篇 |
基础医学 | 1618篇 |
口腔科学 | 288篇 |
临床医学 | 1352篇 |
内科学 | 2962篇 |
皮肤病学 | 274篇 |
神经病学 | 916篇 |
特种医学 | 452篇 |
外国民族医学 | 2篇 |
外科学 | 1426篇 |
综合类 | 1097篇 |
一般理论 | 2篇 |
预防医学 | 1066篇 |
眼科学 | 483篇 |
药学 | 1068篇 |
6篇 | |
中国医学 | 354篇 |
肿瘤学 | 971篇 |
出版年
2024年 | 24篇 |
2023年 | 128篇 |
2022年 | 255篇 |
2021年 | 458篇 |
2020年 | 306篇 |
2019年 | 370篇 |
2018年 | 541篇 |
2017年 | 382篇 |
2016年 | 370篇 |
2015年 | 491篇 |
2014年 | 577篇 |
2013年 | 680篇 |
2012年 | 996篇 |
2011年 | 1070篇 |
2010年 | 631篇 |
2009年 | 438篇 |
2008年 | 732篇 |
2007年 | 758篇 |
2006年 | 649篇 |
2005年 | 696篇 |
2004年 | 612篇 |
2003年 | 594篇 |
2002年 | 562篇 |
2001年 | 459篇 |
2000年 | 494篇 |
1999年 | 388篇 |
1998年 | 116篇 |
1997年 | 98篇 |
1996年 | 101篇 |
1995年 | 89篇 |
1994年 | 52篇 |
1993年 | 50篇 |
1992年 | 143篇 |
1991年 | 118篇 |
1990年 | 102篇 |
1989年 | 107篇 |
1988年 | 88篇 |
1987年 | 75篇 |
1986年 | 66篇 |
1985年 | 50篇 |
1984年 | 38篇 |
1983年 | 23篇 |
1982年 | 13篇 |
1981年 | 9篇 |
1980年 | 11篇 |
1979年 | 14篇 |
1977年 | 12篇 |
1973年 | 9篇 |
1970年 | 9篇 |
1965年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Rodríguez Montalbán R Martínez de Guereñu Alonso MA Pérez-Cerdá Silvestre F Cortés Guerrero M del Campo Sánchez I Real Navacerrada MI Dávila Muñoz P 《Revista espa?ola de anestesiología y reanimación》2000,47(10):480-484
Arterial catheterization is a simple technique that yields great benefits, such as continuous monitoring of arterial pressure and the possibility of taking repeated samples for analysis. However, it is not free of complications, the main ones being limb ischemia and gas embolism. To reduce the risk of complications, guidelines for insertion and maintenance of arterial catheters have been established. We report two cases of acute hand ischemia secondary to arterial catheterization. Both patients were undergoing surgery for sarcoma-type abdominal cancer and developed acute ischemia of the hand lasting several hours. The predisposing factor in both cases was the existence of a highly advanced sarcoma-type abdominal tumor, probably related to a state of hypercoagulability. 相似文献
82.
目的总结分析新生儿缺氧缺血性脑病(HIE)发病的相关因素及临床特征。方法对79例临床诊断为HIE新生儿的发病相关因素、CT表现等进行分析。结果羊水污染占56%,胎膜早破占42%,脐带绕颈占39%,妊高征占30%,母贫血占13%,其中存在两种因素占30%。全部病例中CT检查76例有异常表现,阳性率96%,合并蛛网膜下腔出血占61%,合并脑室出血占15%,脑室内出血羊水Ⅲ度污染占58%,重度窒息占67%,分析颅内出血的发病因素,其中有两种异常因素占50%。早产儿有71%存在脑室内出血。结论羊水污染是HIE发生的首要因素,脑室出血与羊水Ⅲ度污染及重度窒息关系密切,早产儿易合并脑室出血。要加强围产期预防,对产科异常因素,临床有症状的新生儿,颅脑CT应作为常规检查手段。 相似文献
83.
84.
Energy harvesting devices made of piezoelectric material are highly anticipated energy sources for power wireless sensors. Tremendous efforts have been made to improve the performance of piezoelectric energy harvesters (PEHs). Noticeably, topology optimization has shown an attractive potential to design PEHs with enhanced energy conversion efficiency. In this work, an alternative yet more practical design objective was considered, where the open-circuit voltage of PEHs is enhanced by topologically optimizing the through-thickness piezoelectric material distribution of plate-type PEHs subjected to harmonic excitations. Compared to the conventional efficiency-enhanced designs, the open-circuit voltage of PEHs can be evidently enhanced by the proposed method while with negligible sacrifice on the energy conversion efficiency. Numerical investigations show that the voltage cancellation effect due to inconsistent voltage phases can be effectively ameliorated by optimally distributed piezoelectric materials. 相似文献
85.
Rationale:To report a rare case of calculating the IOL power in a cataract patient who underwent both radial keratotomy (RK) and photorefractive keratectomy (PRK).Patient concerns:A 48-year-old woman underwent bilateral RK at age 22 and bilateral PRK at age 46. She developed bilateral corneal haze and corneal endothelial inflammation and received steroids therapy for long time after PRK. Then she was referred to our hospital due to decreased vision in the both eyes.Diagnoses:The patient was diagnosed with binocular complicated cataract, corneal haze, high myopia and post corneal refractive surgery (RK and PRK).Interventions:The patient underwent bilateral phacoemulsification. The IOL power was calculated using SRK/T formula for RK and Haigis-L formula for PRK, respectively. We finally selected the Haigis-L formula and the intraocular lens (SN60WF) was implanted within the capsular bag.Outcomes:After the surgery, both eyes showed myopia drift, and the right eye continuously fluctuated in refractive results. However, by nearly 1 year later, refractive results in both eyes had stabilized, and no other complications had occurred.Lessons:IOL power in patients who undergo both RK and PRK can be reliably calculated using the Shammas-PL, Average of multiple formulas, or Barret True-K No History formulas. Haigis-L formula is not suitable. Such patients require at least three months after surgery to attain refractive stability in both eyes. 相似文献
86.
The high-dose glucocorticosteroid (GC) treatment is the first choice for dermatomyositis complicated with interstitial lung disease (DM-ILD) but patients are resistant to the high-dose GC monotherapy. Besides, the high dose of GC, the secondary immunosuppressive agent(s) is necessary but there is controversy for the selection of immunosuppressive agent(s). The objectives of the study were to analyze the efficacy of different therapeutic options for DM-ILD to identify the optimal therapy. A total of 60 patients had received intravenous 1.0–2.0 mg/ kg/day prednisolone for DM-ILD. In severe conditions, patients had received oral 1 to 3 mg/day tacrolimus (TAC), 500 mg/ m2/month cyclophosphamide (CY), and/or 1 g/ day methylprednisolone pulse (TI cohort, n = 24). In severe conditions, patients had received 1 g/day methylprednisolone pulse and 2–3 mg/ kg/day cyclosporine A (CsA) and/or 500 mg/ m2/month CY (existing historical treatment; CT cohort, n = 36). Patients of the TI cohort did not receive CsA. Patients in the CT cohort were received CY in significantly fewer numbers than those of the TI cohort during treatment (P = .0112). A total of 11 (46%) patients from the TI cohort and 14 (39%) patients from the CT cohort were developed relapsed. At the end of the 30-months, higher numbers of patients of the TI cohort had an event(s) free survival than those of the CT cohort (7 (29%) vs 2 (6%), P = .0229). Also, higher numbers of patients of the TI cohort had survived irrespective of an event(s) than those of the CT cohort (21 (87%) vs 22 (61%), P = .0399). Patients of the TI cohort had developed herpes zoster (2 (8%)) and cytomegalovirus (4 (17%)) infections. Patients of the CT cohort developed renal dysfunction (10 (28%)). Hyperglycemia, hyperlipidemia, and fracture (GC-related toxicities) were also reported in both cohorts and these toxicities were fever in the TI cohort. The addition of TAC to high doses GC with CY is an ideal treatment for severe conditions of DM-ILD (Level of Evidence: III; Technical Efficacy Stage: 4). 相似文献
87.
测定胃癌患者肿瘤组织与外周血中前列腺素E2的临床意义 总被引:4,自引:0,他引:4
目的 测定胃癌患者肿瘤组织及外周血中前列腺素E2(prostaglandin E2,PGE2)含量.方法 用PGE2酶联免疫试剂盒分别测定40例胃癌患者肿瘤组织、癌旁切缘组织及术前外周血中PGE2含量.结果 胃癌组织的PGE2含量明显高于癌旁切缘组织,分别为(8.225±2.425)、(1.669±0.287)ng/g,两者差异有统计学意义(P<0.01),低分化和高中分化胃癌组织PGE2含量分别为(9.02±2.28)、(5.38±0.35)ng/g,两者有显著性差异(P<0.05).外周血中PGE2含量与胃癌组织PGE2含量呈正相关(r=0.889,P<0.01).肿瘤直径≥5 cm和<5 cm的胃癌患者外周血中PGE2含量差异有统计学意义(P<0.05).低分化和高中分化胃癌患者外周血中PGE2含量差异也有统计学意义(P<0.05).胃癌组织及外周血中PGE2含量与患者年龄、性别无关,与肿瘤部位、浸润深度、临床病理分期及是否淋巴结转移也无关.结论 胃癌患者肿瘤组织中PGE2含量增高,其外周血PGE2含量也随之增高,表明外周血PGE:水平与胃癌组织释放的PGE2含量成正比.测定外周血中PGE2可以间接评估胃癌患者的肿瘤大小与分化程度. 相似文献
88.
Talamini R Vaccarella S Barbone F Tavani A La Vecchia C Herrero R Muñoz N Franceschi S 《British journal of cancer》2000,83(9):1238-1242
In an Italian case-control study of oral cancer, number of missing teeth and other aspects of dental care were similar, but the general condition of the mouth, as indicated by gum bleeding, tartar deposits and mucosal irritation, was worse among oral cancer cases than controls. No differences were detected in sexual practices (including oral sex) and (previous) sexually transmitted infections. 相似文献
89.
90.
Dedifferentiated liposarcoma (DDLPS) is a rare subtype of liposarcoma with a poor prognosis. This current case report describes a rectal DDLPS in a 68-year-old Chinese male that presented with lower abdominal pain and weight loss. Computed tomography and magnetic resonance imaging were undertaken to evaluate the tumour. The patient underwent radical resection of the rectal tumour, sigmoid colostomy and partial ureterectomy. The tumour was positive for mouse double minute 2 by immunohistochemistry. The patient healed well but refused chemotherapy postoperatively for economic reasons. The tumour recurred and metastasized 4 weeks after the operation. After relevant treatment, the patient''s condition deteriorated and he died of shock, metabolic acidosis, hyperlactataemia and acute renal failure. The case report also reviews the literature in terms of the clinical diagnosis, treatment and pathological characteristics of rectal DDLPS with the aim of improving the level of diagnosis and treatment. 相似文献